text:
Geological Setting
Analytical Procedures
Discussion and interpretation
Special issue statement
ADGEO | Articles | Volume 47
Adv. Geosci., 47, 1–15, 2019
https://doi.org/10.5194/adgeo-47-1-2019
New insights into the Gondwana breakup at the Southern South America by apatite fission-track analyses
New insights into the Gondwana breakup at the Southern South America by apatite fission-track analyses New insights into the Gondwana breakup at the Southern South America by apatite fission-track... Cristiane H. Gomes and Delia Almeida
Cristiane H. Gomes and Delia Almeida Cristiane H. Gomes and Delia Almeida Cristiane H. Gomes and Delia Almeida
Laboratório de Mineralogia e Petrografia, Universidade Federal do Pampa, Caçapava do Sul, 96570-000, Brazil
Correspondence: Cristiane H. Gomes (cristianegomes@unipampa.edu.br)
Received: 27 Jul 2018 – Revised: 06 Jan 2019 – Accepted: 07 Jan 2019 – Published: 21 Jan 2019
Apatite fission-track (AFT) analyses, applied to Southern Brazil and Uruguay samples, was employed aiming to understand the low temperature history of the Dom Feliciano Belt Segment. The Dom Feliciano Belt formed during the Neoproterozoic to Early Paleozoic, linked to the Brasiliano/Pan-African Orogeny. Twenty-four samples were dated, and confined track lengths of twenty samples were measured. The spatial distribution of ages shows three domains with different evolution cut by shear zones and, or suture zones in the Dom Feliciano Belt. The Western Domain exhibits AFT ages > 250 Ma (Permian to Devonian) while the Eastern Domain shows AFT ages < 230 Ma (Paleogene to Triassic). In the Central Domain, the AFT ages range from ∼196 to 130 Ma (Jurassic to Early Cretaceous). The thermal modeling in the domains revealed a complex evolution, with cooling and reheating phases, and a denudation of ∼2600 m. The AFT ages clearly postdate the Gondwanide, Paraná-Etendeka and Rio Grande Cone exhumation history of the Dom Feliciano Belt.
Article (PDF, 3445 KB)
How to cite.
Gomes, C. H. and Almeida, D.: New insights into the Gondwana breakup at the Southern South America by apatite fission-track analyses, Adv. Geosci., 47, 1–15, https://doi.org/10.5194/adgeo-47-1-2019, 2019.
The South America passive continental margin draw itself through several tectonic episodes that began in the Neoproterozoic (Almeida et al., 2000). These episodes are related to the breakup of continents, lithospheric and mantle dynamics. The transitions between Uruguay and Rio Grande do Sul State, Brazil, represents an evolutionary key area for the Gondwana Breakup of the lithospheric plates of South America and Africa. Several tectonic events took place during the Neoproterozoic to Cambrian, including accretionary orogenic processes that marked the transition from stable to unstable tectonic conditions. These processes, such as granite magmatism and metamorphism, (e.g. Piedra Alta and Nico Perez Terrane, in Uruguay, and Sul-rio-grandense Shield basement, in Brazil) have been recorded in many places (Bossi et al., 1998; Preciozzi et al., 1999; Chemale Jr. et al., 2012). Post-collisional processes occurred in the passive margin, mainly including foreland tectonics, extension-related intrusions, and isostatic adjustments (Chemale Jr. et al., 2005, 2012; Basei et al., 2008; Rapela et al., 2011; Saalmann et al., 2011). The Gondwana's formation occurred during Neoproterozoic to Cambrian by fusion of at least five cratons, among them the Rio de la Plata, Kalahari and Congo Cratons. The interactions among these cratons formed the Dom Feliciano Belt in Brazil and Uruguay (Philipp et al., 2016). In the Late Paleozoic, the Gondwanide Orogeny climate changes, including glaciations records in the Itararé Formation, Brazil, and tectonic affected the Gondwana margins. The cold climate gradually changes to temperate and humid atmosphere. The cold climate gradually changed to the temperate and humid atmosphere. A sedimentary sequence of siliciclastic rocks, associated with intrusion and extrusion of the Paraná-Edendeka Suit (Zalán et al., 1990), then overlain The Precambrian basement.
The tectonic evolution of the Uruguay and Rio Grande do Sul State in Brazil, is marked by metamorphic rocks and intrusions reworked of the Neoproterozoic, partly overlain by a thick sequence of Paraná rocks (Zalán et al., 1990). Milani et al. (1997) characterized six megasequences for the Paleozoic and Mesozoic intervals of the Parana Basin, where the depositional history was controlled by tectonism and climatic changes. Subparallel fault and fracture zones to the coastline were reactivated and over them the deposition of the Pelotas Basin (Fig. 1; Tomazelli and Willwock, 2000). Many of these records are known in Southern Brazil through thermochronological studies (Gallagher et al., 1994, 1995; Borba et al., 2002; Tello et al., 2003; Hackspacher et al., 2004; Gomes, 2011; Hiruma et al., 2010; Franco-Magalhães et al., 2010; Siqueira-Ribeiro et al., 2011; Chemale Jr. et al., 2012; Karl et al., 2013; de Oliveira et al., 2016). These works suggest reactivation of the Precambrian structures and plate adjustment of breakup associated with the South Atlantic rift evolution. In addition to studies in restricted areas that suggest denudation in the NW cratonic interior of the Sul-rio-grandense Shield.
Figure 1Simplified geological map of the Dom Feliciasno Belt in Uruguay and Rio Grande do Sul State, Brazil, and shear zones showing samples locations. Regional distribution of AFT ages (±1σ) of the working area. In the blue boxes, AFT ages of West Domain of Dom Feliciano Belt; in the white boxes, AFT ages of Central Domain; and in the yellow boxes, AFT ages of East Domain (adapted after Castillo Lopes, 2009; Chemale Jr. et al., 2012; de Oliveira et al., 2016; and Gruber et al., 2016).
In order to improve the understanding of the Gondwana breakup at the Southern South America by thermochronological studies twenty-four new apatite fission-track data of granitic and gneiss rocks from the Uruguay and Southern Brazil were obtained. The results of this study provide a simplified model of the large-scale geodynamic evolution of the Dom Feliciano Belt Segment through time should be given, especially uplift and erosion (cooling), subsidence and magmatism (heating), and timing of the movement of large onshore faults and shear zones. It is a significant effect on the evolutionary history of the Sul-rio-grandense and Uruguay Shields.
2 Geological Setting
The Sul-rio-grandense and Uruguay Shields, situated in the Southwest Gondwana, originated from divergent movements between the two lithospheric plates of South America and Africa, with subsequent opening of the South Atlantic. These shields comprise rocks generated between Archean and Ordovician including Dom Feliciano Belt.
The Dom Feliciano Belt forms a discontinuous belt, bounded by NE–SW and NW–SE oriented regional Brasiliano Shear Zone (Fig. 1). This Belt is subdivided into three units by Fernandes et al. (1995), which are denominated Central, East, and West Dominions, from gravimetric data and separated by suture and shear zones. The Western Domain separated from the Central by NE–SW trending Caçapava Suture (Fig. 1), being formed by granitic-gneissic-magmatic rocks associated with multiple magmatic intrusions, which are predominantly located along the Major Gercino Shear Zone (Fig. 1; Chemale Jr. et al., 2012). The Major Gercino Shear Zone has a NE–SW oriented and is an important formation that separates the magmatic arc granites to the East and a folded supracrustal belt to the West. This domain is formed by Taquarembó and São Gabriel Terranes, Brazil (Fig. 1). The Taquarembó Terrane is composed of Paleoproterozoic granulites with protolith ages of 2.45 Ga (Hartmann et al., 2000), several granite intrusions with age at 0.65–0.55 Ga (Gastal et al., 2006) and Neoproterozoic to Eopaleozoic volcano-sedimentary rocks. The São Gabriel Terrane consists of ophiolite slabs, volcanic-arc-related rocks, granite-gneiss rocks with a Neoproterozoic juvenile signature, volcano-sedimentary rocks and late- to post-orogenic granite intrusions and volcano-sedimentary rocks of Camaquã Basin (Fig. 1; Chemale Jr., 2000; Hartmann et al., 2000; Saalmann et al., 2011).
The Central Domain is formed by part of the Camaquã Basin, Tijucas Terrane and a small part of the Pelotas Batholith (Fig. 1). The Tijucas Terrane (Fig. 1) is composed of metasedimentary rocks intercalated with metavolcanic rocks of the Porongos Complex with ages from ca. 0.5 to 2.8 Ga (Chemale Jr., 2000; Saalmann et al., 2011; Basei et al., 2008; Gruber et al., 2016), granitic-gneissic rocks of the Encantadas Complex. The Encantadas Complex is interpreted as a Paleoproterozoic active continental arc (Saalmann et al., 2011; Philipp et al., 2008) and granitic intrusions and sedimentary rocks. The Pelotas Batholith bounded to the West by the Canguçu Shear Zone, is represented by granite rocks with ages of 650–550 Ma and interpreted as a continental magmatic arc (Hartmann et al., 2000; Philipp and Machado, 2005), tectonically reworked in the Paleoproterozoic (Fernandes et al., 1995). The Camaquã Basin was generated in the late- to post-orogenic sedimentary cycles of the Brasiliano Orogeny in the Dom Feliciano Belt (Chemale Jr., 2000). The basin is NE–SW-elongated and is composed of the following four units:
Maricá Group dated at 601±13 and 593±6 Ma (Almeida et al., 2012; Paim et al., 2014);
Bom Jardim Group, whose age is constrained at 593±625 and 580±3.6 Ma (Almeida et al., 2012);
Santa Bárbara Group dated at 553±5.4 to 549±5 Ma (Almeida et al., 2012); and,
Guaritas Group dated at 547±6.3 Ma and 473.7±9.4 Ma (Almeida et al., 2012). The Eastern Domain separated from the Central by Canguçu-Major Gerciano Shear Zone (Fig. 1). This domain is formed by Pelotas Batholith, previously described.
In Uruguay (Fig. 1), the Dom Feliciano Belt separates into three different units by the Sierra Ballena Shear Zone:
Nico Pérez Terrane
Piedra Alta Terrane; and;
Cuchila Dionísio-Pelotas Batholith (Fig. 1).
The Sierra Ballena Shear Zone is part of a transcurrent system that divided the Dom Feliciano Belt into two different domains: Schist Belt and Granitic Belt (Bossi and Campal, 1992; Bossi et al., 1998; Teixeira et al., 1999). The Schist Belt is correlated in Brazil to the Porongos Group (Basei et al., 2008) and the Granite Belt is correlated with the Pelotas Batholith (Oyhantçabal et al., 2010; Philipp and Machado, 2005).
The Nico Pérez Terrane (Bossi and Campal, 1992), located East of the Sarandí del Yí Shear Zone (Fig. 1), composed of Archean remnants (> 2.7 Ga, Hartmann et al., 2000) in Paleoproterozoic core and granitoids of ca. 1.8–1.5 Ga, orientated according to NNE–SSW. This terrane was intensely reworked during events at ca. 3.1–3.0, 2.7, 2.2–2.0 Ga (Santos et al., 2003), 1.25 Ga (Bossi et al., 1998) and 540–530 Ma (Gaucher et al., 2011).
The Piedra Alta Terrane defined by Bossi et al. (1998), located in the most Western part of Uruguay – West of the Sarandi del Yí Shear Zone, consists of three Paleoproterozoic belts, with E–W orientation and formed by metavolcanic-sedimentary rocks intercalated by a granite-gneissic chrono-correlated (Dalla Salda et al., 1988; Cingolani et al., 1997; Hartmann et al., 2000). The Piedra Alta Terrane is the root of a juvenile Paleoproterozoic magmatic arc (2.2–2.0 Ga, Hartmann et al., 2002). According to Bossi et al. (1998), Campal and Schipilov (1999) and Teixeira et al. (1999) this terrane was tectonic stable at ca. 1.7 Ga. Mesoproterozoic ages were reported by Bossi et al. (1998) for the Sarandí del Yí Shear Zone suggesting that the Rio de la Plata Craton has been tectonically reworked.
The Cuchilla Dionísio-Aiguá Batholith (Gaucher et al., 2009), located to the East of the belt (Fig. 1), is characterized by Neoproterozoic to Paleoproterozoic granitoids and metagranitoids rocks (Bossi et al., 1998; Preciozzi et al., 1999) and limited from Nico Pérez Terrane by the Sierra Ballena Shear Zone (580–550 Ma, Ar-Ar, Oyhantçabal et al., 2010). This shear zone has continuity in Southern Brazil by the Canguçú Shear Zone (Fernandes and Koester, 1999), which was active at the end of the Neoproterozoic. The Sierra Ballena Shear Zone is marked by strong linear negative gravity anomalies (Hallinan et al., 1993) and probably controlled the intrusion of calc-alkaline granites (Bitencourt and Nardi, 1983). The Aiguá Batholith (Fig. 1) has been correlated with the Pelotas Batholith and is interpreted as the root of a Neoproterozoic magmatic arc.
Southern South America is affected by a very extensive glaciation at the Carboniferous-Permian (350–250 Ma) (Mcloughln, 2001) with the register of the Itararé Group (de Freitas-Brazil, 2004). At the same time, the Gondwanide Orogeny compressed and deformed the cratonic areas on the West and South Gondwana margins (e.g. Sierra de la Ventana, Uruguay) (Ramos, 1988) and formed the backbone of Uruguay and Rio Grande do Sul basement (Milani, 1997). In addition, the absence of records of sedimentation in Southern Brazil confirms that the basement was active (Milani, 1997). While in the Permian-Triassic the development of the lineaments with E–W direction parallels the zones of oceanic fractures, which can be related to the later development of the South Atlantic (Zalán et al., 1990). Parts of Gondwana rotated over the Southern during the Late Paleozoic (Mcloughln, 2001). The pre-existing structures (from Pre-Cambrian, Paleozoic and Triassic) collaborated with the South Atlantic opening and accommodated the deposition of Paraná Basin (Milani, 2000). The Paraná Basin has an elongated shape of almost 1 100 000 km2 and extends in a Southwest-Northeast direction throughout Brazilian Territory, Paraguay, Uruguay, and Argentina. According to Milani (1997) and Zerfass et al. (2003) this tectonic pattern is observed on the Gondwana Supersequence II (Rio Bonito, Palermo, Irati, Serra Alta, Rio do Rastro and Pirambóia formations). Franco-Magalhães et al. (2010) suggest that up to ∼6000 m of siliciclastic sedimentary rocks fill the old erosional topography with the Paraná flood basalt surface.
In the Neocomian (145–130 Ma) the rift phase began, which was followed by ascending intrusive bodies through fractures of the crust. Among them the Serra Geral magmatism with an age 134.5 Ma (Pinto et al., 2011; Janasi et al., 2011), which used to ascend by older structures with NW–SE direction. After the Serra Geral magmatism the substrate of the region was shaped (Milani, 2000) and on subparallel faults to the coastline of the basement was deposited the Pelotas Basin (Tomazelli and Villwock, 2000). The Pelotas Basin is located in South Atlantic between Brazil and Uruguay. It is limited in its Northern part with Santos Basin through the Florianopolis Fracture Zone. In the Southern, it is limited by Chui Lineament, which separated it from Punta del Este Basin, Northern Uruguay. Structural data of these margins indicate that Pelotas Basin was controlled by tectonic stages of at South Atlantic pre-syn and post-rifting and affected by high-angle extensional faults (Bassetto et al., 2000; Contreras et al., 2011). Pelotas Basin covers more than 200 000 km and includes Rio Grande Cone (Fig. 1). The Rio Grande Cone is a depositional feature formed during the Neogene and ultra-deep, which can reach 3600 m (Fontana, 1989).
The Late Cretaceous stable conditions have been recorded from fission-track ages (90–60 Ma, Gallagher et al., 1994), which refer to the sedimentation cycle in SE South America. Gallagher et al. (1994) suggest these thermochronological ages represent the Paraná-Etendeka volcanic suite event. These authors proposed an apatite fission-track (AFT) age-elevation relationship coupled with the occurrence of older ages (with AFT ages > 300 Ma) within very close geographic proximity to younger ones (90–60 Ma). The exhumation and denudation of high-elevated areas during the Late Cretaceous, in response to the drift of South America over of the Trindade hotspot, were dated by thermochronological data and the AFT ages was close to 90 Ma (Meisling et al., 2001; Tello et al., 2003; Hackspacher et al., 2004).
Data and information from tectonic events associated with residual weathering and sediments over paleosurfaces from Southeastern South America are compared to potential correlative sequences either in a continental interior as Santos Basin and to regional rifting basins. Uplift and ages are interpreted from AFT in literature. In the Pelotas Basin, the evidence of exhumation of the coastal mountain source area in the Paleogene is a thick sequence of sediments prograding outward, being known as Rio Grande Cone (Castillo Lopes, 2009). Franco-Magalhães et al. (2010) suggest that Paleocene-Eocene thermochronological ages indicate block faulting and exhumation of the flanks along of the Paleogene rifts. In the onshore, from Paleocene to Miocene (60–20 Ma), half-grabens trending NNE–SSW and are filled up by terrigenous sediments of more than 800 m (Melo et al., 1985; Almeida et al., 2000; Cobbold et al., 2001; Meisling et al., 2001; Salamuni et al., 2003; Karl et al., 2013).
The South Atlantic opening still involves numerous uncertainties, like locations and magnitudes of overlaps between continental rocks, but it is accepted that initiated in the Southern Argentinean–African margins and propagated Northward to the Brazilian and African margins (Moulin et al., 2010).
3 Analytical Procedures
Twenty-four new samples were collected along the Western, Central and Eastern Domains of the Dom Feliciano Belt. We focused on the area where we considered there to be the best opportunities to identify the evolution of the Gondwana breakup. In the Western Domain, three samples were collected in the Piedra Alta Terrane, and three samples in the Nico Perez Terrane (Uruguay). In Southern Brazil, in this domain, two samples were collected in the Taquarembó Terrane and one sample to the Western of Caçapava Suture in the São Gabriel Terrane. In the Central Domain, one sample was collected to the East of Caçapava Suture in the Camaquã Basin, and one sample in the Tijucas Terrane and two samples to the West of Sierra Ballena Shear Zone in the Cuchilla Dionísio Terrane (Uruguay). In the Eastern Domain, ten samples were collected in the Pelotas Batholith (Brazil), one sample in the Aiguá Batholith and two samples in the Cuchilla Dionísio Terrane (Uruguay). In total, nine samples from Uruguay and 16 samples from Southern Brazil (Fig. 1; Table 1).
Table 1Apatite fission-track data from the Uruguay and Rio Grande do Sul state, Brazil.
N: number of grains analyzed to determine track densities; ρs: measured spontaneous track density; Ns: number of spontaneous tracks counted; ρi: measured track density; ρi: number of induced tracks counted; ρd: track density measured in glass dosimeter;
Nd: number of tracks counted in determining ρd; χ2: Chi-square probability; n: number of confined tracks lengths measured; MTL: mean track length; Dpar: mean etch pit diameter of all measured etch pits; SD: standard deviation of track length distribution
of individual track measurements: (–): not analyzed. Note: AFT ages were calculated by Cristiane H. Gomes ξ CN1=111.36±9.65 and CN5=373.89±19.2 respectively.
Download Print Version | Download XLSX
Apatite minerals were separated and isolated from each sample following procedures outlined in Dumitru (1999) using standard gravimetric and magnetic mineral separation techniques. The natural apatite was mounted in epoxy, polished and etched in 5N HNO3 for 25 s at 25 ∘C to reveal the spontaneous fission-track. All AFT ages were performed using low-U mica sheets as external detector method (Gleadow and Lovering, 1977). Apatite samples were irradiated at the IPEN-CNEN nuclear reactor, São Paulo State, Brazil, with two glass neutron dosimeters (CN5 and CN1) with known uranium content together with Fish Canyon Tuff age standards and Durango apatite age standards (Hurford and Green, 1983; Green 1985). After irradiation, mica detectors were etched in 48 % HF for 18 min at 20 ∘C to reveal the induced fission-tracks. The AFT analyses on all samples were performed at the Federal University of Rio Grande do Sul, Brazil, using a Zeiss Axioplan 2 imaging with Autoscan® system by the first author. AFT central ages were calculated according to the ξ-calibration method (Hurford, 1990; Hurford and Green, 1983). The AFT age errors are quoted at the 1σ confidence level and were derived by the conventional method (Green, 1985). The χ2-squared test was used to quantify age homogeneity; when P(χ2) > 5 %, fission-track samples contain a single age population (Gallagher et al., 1995). The AFT age calculation, their dispersion, and distribution were obtained by the Trackkey® v. 4.2 Software (Dunkl, 2002).
Confined track lengths were measured on horizontal confined fission tracks following procedures Laslett et al. (1982) to construct an apatite fission-track length-frequency distribution. The apatite composition in term of chlorine and fluorine was carried out in the Department of Geology, Federal University of Rio de Janeiro State, Brazil, using a JEOL JXA-8230 Electron Microprobe with 15 kV accelerating voltage, 25 nA current, and 5–20 µm beam diameter.
The thermal histories were modeled using AFTSolve 1.4.1 (Ketcham et al., 2000). The time–temperature evolutions tested against the thermochronological data set are determined by using the published geological history of the area. The inversions modeling was run with 10 000 randomly chosen time–temperature (t--T) histories for each sample. Thus, the model paths were available to clearly differentiate between "goodness of fit" and "acceptable fit" solutions depending on the ages and lengths parameters and the geological background and cooling history of different areas. The initial inverse modeling is based on the best forward model revealed. We restricted the conditions for inversion modeling as follows:
as initial constraint the end of the Brasiliano Orogeny (ca. 550–450 Ma);
a large t−T box was imposed with T closed limits in the base of the apatite partial annealing zone temperature (120 ∘C) and at the paleosurface temperature (20±10 ∘C);
a present mean surface temperature of ca. 20±5 ∘C provided the final modeling constraint. The annealing model used was of Ketcham et al. (1999), with Cl content values as a kinetic parameter and Dpar (ppm) values (Donelick et al., 2005).
4.1 Apatite fission-track age distribution
The AFT ages and confined track lengths measured from studied samples are presented in Table 1, Figs. 1 and 2. The thermal histories for all samples are presented in Figs. 3–5. AFT central ages measured in the West Domain range from 383.4±40.9 (sample RS-6) to 250±21 Ma (sample RS-12). In the Central Domain the AFT central ages range from 196.2±14.7 Ma (sample RS-11) to 130.2±13.3 Ma (sample RS-7), and in the East Domain the AFT central ages range from 262.2±29.9 Ma (sample PJV-5) to 38±2.5 Ma (sample U-1), which closely matches the range determined by de Oliveira et al. (2016) and Kollenz (2015) (Fig. 2). The AFT age distribution allows the separation of the Western Domain with older ages (> 250 Ma) and the Eastern Domain with younger ages (< 230 Ma). One sample, taken from Pelotas Batholith revealed a central age of 262.2±29.9 Ma (sample PJV-5) much larger than the AFT ages from this domain. Zalán et al. (1990) suggest the development of the lineaments with E–W direction related to the South Atlantic rifting and the opening of the ocean in the Permian-Triassic. On the other hand, one sample from the Aiguá Batholith (Uruguay) revealed a central age of 38±2.5 Ma (sample U-1) much lower than the AFT ages from this domain. Franco-Magalhães et al. (2010) suggest that Paleocene-Eocene AFT ages indicate normal re-activation of old Brasiliano/Pan African Shear Zones along the Paleogene rifts. Thus, the Eastern Domain without these two samples, in particular, has AFT ages ranging from 226.7±28 Ma (sample U-8) to 70.3±5.2 Ma (PJV-7).
Figure 2Variation of fission-track ages (Ma) and elevation (m) for the samples from Uruguay and Southern Brazil. Data from de Oliveira et al. (2016) and Kollenz (2015) to comparation.
Figure 3Thermal history of samples from the Western Domain. The numerical modelling used the software code AFTSolve (Ketcham et al., 1999). The temperature and time paths and the confined track length distributions are overlain by a calculated probability density function (best fit). The diagram on the left show four different fits: green paths are the acceptable fit; pink paths are the goodness of fits; and blue-red line is the best fit. The red line represents the moment of the heating. G.O.F.: goodness of fit, N: number of single grain ages and measured track length (MTL).
Figure 4Thermal history of samples from the Central Domain. For detailed description see caption of Fig. 3.
Figure 5Thermal history of samples from the East Domain. For detailed description see caption of Fig. 3.
4.2 Confined track-lengths
The dataset has more than 20 grains per sample (except for the samples U-7 and U-10 from Uruguay and, PJV-10 and PJV-14 from Brazil). The confined track lengths measured are unimodal with a range from 14 (sample U-3) to 106 (sample PJV-17), suggesting, in general, thermal histories with slow-cooling. In addition, they do not display the boomerang form, which is characteristic of a rapid cooling (Gallagher et al., 1994; Green, 1985). The Measured Track Length (MTL) ranges from 9.23 µm (sample PJV-7) to 12.53 µm (sample U-4) with an average of 10.8 µm. In the West Domain the MTL ranges from 10.02 µm (sample U-3) to 12.53 µm (sample U-4), and in the East Domain, the MTL ranges from 9.23 µm (sample PJV-7) to 12.02 µm (sample RS-8). According to Gallagher et al. (1994), the mean confined track length decreases slightly with age. The relationship between AFT age and the shape of the confined track length distributions is characteristic of samples that recorded various degrees of thermal annealing which occurred prior to a common episode of cooling (Gallagher et al., 1994).
Only one sample of the West, Central and East Domains did not present confined track length. The sample of the West Domain is located in the Piedra Alta Terrane, Uruguay, (U-10) with an AFT age of 121.9±19 (Fig. 1, Table 1). The sample of the Central Domain is located in the Tijucas Terrane, Brazil, (RS-7), whose AFT age is 130.2±13.3 Ma. The sample of the East Domain is located in the Pelotas Batholith, Brazil, (PJV-5), which shows AFT age of 262.2±29.9 Ma. These samples could not be modeled due to lack of confined track length, suggesting that apatites undergo high temperature (> 120 ∘C). The fission-track will be annealed, and the fission-track system will recount. In the Early Permian, the Paraná Basin expanded considerably reaching Rio Grande do Sul State, Brazil, with structural modification in the substratum of the basin by subsidence and sedimentation.
The apatite chemical compositions were determined in order to establish the influence of fluorine and chlorine content on the annealing process. The analyzed grains are all fluorapatite (Donelick, 1991) with mean chlorine content range from 0.003 to 0.259 wt % and low resistance to annealing (O'Sullivan and Parrish, 1995).
4.3 Age-elevation
The correlation between AFT ages and elevation study here show old ages often occur within very close geographic proximity to young ones. All AFT central ages are much younger than the Brasiliano/Pan-African Orogeny that affected the Sul-rio-grandense Shield and Uruguay rocks before 500 Ma. The collective AFT dataset from Uruguay shows a systematic correlation between AFT age and elevation (Fig. 2). This relationship indicates a positive correlation between elevation and distance West and East of the Sierra Ballena Shear Zone, with an apparent uplift rate calculated of 40 m Ma−1 during the Eocene. We, therefore, interpret this relationship as the reflection of the regional topography which is characterized by an elevated interior plateau separated from the coastal region by a Sierra Ballena Shear Zone. Based on geomorphology, the Sierra Ballena Shear Zone has separated into three sectors: Southern, Central and Northern. The Northern and Southern sectors are a strong contrast between the quartz mylonites and mylonitic porphyries of the shear zone (Schist Belt), which are more resistant to weathering, and the country rocks. In the central sector, the Granite Belt (Aiguá Batholith) and the low relief are associated with Mesozoic Basin (Oyhantçabal et al., 2010). This implies that the Uruguay region probably attained positive relief during the Late Cretaceous. During the Paleocene, the area was eroded and exhumed, which probably contributed to fill basins formed by rifting (Oyhantçabal et al., 2010). However, only the U-1 sample has an AFT age of 38±2.5 Ma indicating that it was cooling during uplift and erosion in the Eocene, at about the time that Rio Grande Cone was formed in the Pelotas Basin (Castillo Lopes, 2009).
In Southern Brazil, the correlation between AFT age and elevation (Fig. 2) is not obviously related to age and distance to the coast, through the ages show a tendency to increase with altitude. The majority of the samples were collected from elevations < 353 m; although only one sample from somewhat higher elevation (422 m) was collected from the summit surfaces of the Canguçu Shear Zone (Table 1, Fig. 2).
4.4 The thermal modeling results
The thermochronological data exhibit a complex thermal history at the Uruguay and Brazilian margins, which had record in the Permo-Carboniferous and Gondwanide Orogeny (Figs. 3, 4 and 5). For example, the Uruguay registers heating processes in the Anisian-Tithonian to Aptian, possibly associated with the Jurassic-Cretaceous continental rifting that affected the region. Already in Southern Brazil the thermochronological data show the Paraná Basin deposition, the Serra Geral magmatism, and the Rio Grande Cone evolution. The thermal modeling shows that the presently exposed rocks of Uruguay and Southern Brazil were at temperatures around 70 ∘C during the Jurassic-Cretaceous period. In this way, the rocks present at the surface were at depths of at least ∼2360 m at that time, for a paleogeothermal gradient of 25 ∘C km−1 (Raab et al., 2002; Luft et al., 2005; Tinker et al., 2008). It could be assumed that the thermal modeling results reflect ongoing slow exhumation during the Jurassic-Cretaceous. In addition, our confined track length data, presenting a wide distribution and short mean values (Table 1) could be a result of continuous slow cooling from temperatures in excess of 120 ∘C to surface temperatures (Gleadow, 1986).
The Western Domain of Dom Feliciano Belt (Fig. 3) is characterized by an initial very fast period of cooling during the Cambrian from 120 to 60 ∘C in the Taquarembó Terrane, Brazil (sample RS-5). During the Devonian from 200 to 70 ∘C (sample U-2) and 90 to 70 ∘C (sample U-3) in the Nico Perez Terrane, Uruguay. This was followed by a slow period of cooling to the Carboniferous-Permian from 70 to 60 ∘C (Fig. 3). After a final, a very fast period of cooling in the Eocene to Oligocene to almost surface temperatures (∼25 ∘C). In the Devonian, the Piedra Alta Terrane is characterized by a rapid period of reheating from 30 to 80 ∘C (sample U-4), which extends until the Late Jurassic as a slow period of reheating from 20 to 80 ∘C (sample U-5).
The Central Domain of Dom Feliciano Belt (Fig. 4) displays slow and fast intercalated periods of cooling since the Devonian from 80 to 50 ∘C in the Camaquã Basin (sample RS-11). However, the Cuchilla Dionísio Terrane, Uruguay (sample U-7), reveals a very fast period of cooling at the Triassic boundary from 80 to 50 ∘C, followed by a period of reheating in the Jurassic to 50 to 80 ∘C (Fig. 4). After a final slow period of cooling in the Cretaceous-Paleogene to 80 to 60 ∘C. In the Eocene to Oligocene both Camaquã Basin, Brazil, and Cuchilla Dionísio Terrane, Uruguay, are characterized by a fast period of cooling to almost surface temperatures (∼25 ∘C).
The East Domain of Dom Feliciano Belt is characterized by periods of variation of temperature mainly in the Pelotas Batholith. During the Ordovician-Late Carboniferous, the region presents initial periods of reheating from 110 to 170 ∘C (samples PJV-2, PJV-4 and PJV-17, Fig. 5), at the same time a fast-moderate cooling from 170 to 30 ∘C (sample PJV-6) occurs. In the Jurassic-Cretaceous a slow cooling is observed (∼60 ∘C) in both the Pelotas Batholith, Brazil, and in Cuchilla Dionísio Terrane, Uruguay. However, the Pelotas Batholith reveals a very fast period of heating in the Triassic (sample PJV-6) that extends to the Oligocene (sample PJV-4).
5 Discussion and interpretation
The exposes rocks from the uplifted region at the South America passive continental margin in Southern Brazil and Uruguay are formed at the Paleoproterozoic due to the collision of Rio de la Plata, Kalahari and Congo cratons reworking. There were subsidence and exhumation which marked the tectonic evolution in Southern Brazil and Uruguay (Almeida et al., 2000; Gomes, 2011; Rapela et al., 2011; Saalmann et al., 2011; Chemale Jr. et al., 2012; Philipp et al., 2016). In this crustal domain, during the Gondwana Orogeny, important NNE–S-trending lineaments were generated (e.g. Sierra Ballena-Major Gercino, Sarandí del Yí in Uruguay and, Canguçu and Ibaré in Brazil) and the oblique movement of the collision tectonic blocks formed the main suture zones (Caçapava, Porto Alegre and São Gabriel in Brazil). These movements are related to both a tangential tectonic regime and a transcurrent, which are characterized by continent-continent collision and low-angle planar structures (Fernandes et al., 1995).
5.1 Ordovician to Permian (Gondwanide Orogeny)
The first episode of cooling was recorded in the samples of the Piedra Alta and Nico Perez Terranes in Uruguay and, Taquarembó and São Gabriel Terranes in Southern Brazil from ∼500 Ma extending up to 260 Ma (Fig. 3). This age interval coincides with three known events in the region of the Western Domain of the Dom Feliciano Belt, being:
the time of cooling through the 300–350 ∘C internal from the biotites and muscovites whose K-Ar age is ca. 570 Ma from mylonites of Major Gercino Shear Zone in Uruguay (McDougall and Harrison, 1999). This age indicates later brittle reactivation of the shear zones in Devonian;
the reactivation of faults related to a late thermal-tectonic event, which have an age range of 540 to 530 Ma (mica Ar-Ar and biotite K-Ar), and were probably responsible for the formation of the Camaquã Basin (Philipp and Machado, 2005);
the shear zone reactivations can be associated with the stabilization phase with low exhumation events of tectonic blocks correlated to the Paraná Basin evolution (Hackspacher et al., 2004). Enhanced cooling around 500–260 Ma, as indicated by the model (Fig. 3), could explain a denudation rate around 40–560 m in Southern Brazil (sample RS-6) and Uruguay (sample U-2), respectively. At the same time the temperature decreased from 200 to 60 ∘C, corresponding to a greater extensive glaciation (Mcloughln, 2001).
Moreover, we interpret the age of 262.2±29.9 Ma (sample PJV-5) in the East Domain as the reflex of the development of lineaments with E–W direction related to the South Atlantic rifting and the opening of the ocean in the Permian-Triassic.
5.2 Triassic to Jurassic (Post Gondwanide Orogeny)
The AFT ages in the Central and East Domains imply a phase of cooling between 250–150 Ma (Figs. 4 and 5). The samples coming from regions as Camaquã Basin, Tijucas Terrane and Pelotas Batholith in Brazil, and Cuchilla Dionísio Terrane in Uruguay close to tectonic lines (Sierra Ballena, Canguçu, Major Gercino, Passo do Cação Shear Zones and, Caçapava and Porto Alegre Sutures), which are interpreted as reactivated zones (Philipp and Machado, 2005; Oyhantçabal et al., 2010; Gomes, 2011; de Oliveira et al., 2016). Some authors suggest that shear zone reactivations, in the Triassic (206 and 230 Ma), observed in mylonites at Northern Major Gercino Shear Zone are associated with a thermal pulse connected to an early phase of the opening of the South Atlantic (Passarelli et al., 2010). The Major Gercino Shear Zone is a crustal discontinuity that encompasses several anastomosed shear zones, striking NNE and NE with dominant transcurrent kinematics and in which syn-tectonic calc-alkaline, peraluminous and alkaline granites occurred (Oyhantçabal et al., 2010). The Triassic is associated with the formation of a NW-trending grabens, which are probably related to a relaxation of the compressional stress field.
The episodes during the Late Triassic and the Early Jurassic (∼200 Ma) would be related to the distensive regime that operated along the Gondwana margin in the Paleozoic (Keeley and Light, 1993; Milani, 2000; Zerfass et al., 2003), which formed Graben-type basins in Southern South America. In this case this structure is probably associated with thermal pulse to an early phase of the opening of the South Atlantic Ocean (Melo et al., 1985; Riccomini et al., 1989; Almeida and Carneiro, 1998; Almeida et al., 2000; Cobbold et al., 2001; Meisling et al., 2001; Salamuni et al., 2003; Tello et al., 2003). Reheating events during Late Triassic and Early Jurassic (∼200 Ma) is denoted by a temperature increase of ∼60–80 ∘C in the Nico Perez Terrane (Fig. 4, sample U-7) and 50–70 ∘C in the Pelotas Batholith (Fig. 5, sample PJV-6).
5.3 Cretaceous to Recent (Syn- and Post- Gondwana rift evolution)
The second episode of cooling recorded by most samples of the Dom Feliciano Belt, which started in the Cretaceous (150–70 Ma), was slow and continuous (Figs. 3–5) without significant sedimentation taking place with less than 240 m. The rift phase is followed by ascending intrusive bodies through fractures of the crust. Among them the Serra Geral magmatism, which was ascended by older structures with NW–SE direction. The Jurassic-Cretaceous reactivation that culminated in the Serra Geral magmatism, which is related to the Paraná-Etendeka event occurring 134.5 Ma (Pinto et al., 2011; Janasi et al., 2011), shows to be the main event that provided enough heat to erase the fission-tracks of the samples located in the Tijucas Terrane (South Brazil) and Piedra Alta Terrane (Uruguay) (e.g. samples RS-7 and U-10). In this case, the AFT ages of 130.2±13.3 Ma (sample RS-7) were interpreted as the age of spilled magmatism over Southern Brazil and as age of reactivation of old faults in Uruguay during the rifting extension.
The Central Domain, in the Nico Perez Terrane (sample U-2, Fig. 4), and in the East Domain, in the Pelotas Batholith (sample PJV-6, Fig. 5), shows slight reheating episodes at temperatures up to 80 ∘C between 210 and 150 Ma. Thus, the AFT age obtained here is close to this magmatism episode where these samples recorded the South Atlantic syn-rift phase.
The AFT ages of the sample from Pelotas Batholith (samples PJV-7, PJV-14, and PJV-11, Fig. 1) possibly denotes the flexural readjustments, cooling and mechanical accommodation of the oceanic crust of the post-rift phase (Tomazelli and Villwock, 2000) during the Cretaceous (∼70 Ma).
Finally, during the Eocene (∼40 Ma), a denudation episode was recorded in most of the studied samples. The calculated denudation rates are between 32 to 66 m Ma−1 in Uruguay and up to 45 m Ma−1 in Southern Brazil. This restricted interval, in a certain way, may be correlated with the formation of the Rio Grande Cone. According to Fontana (1989), structures related to gravitational movements must have affected the region thermally over the years. During this period, there was a substantial increase of detrital input in the Brazilian continental margin (Barboza et al., 2008), with the development of several deltaic progradation systems over time (Della-Fávera, 2001). Modeling of samples was also shown for the case that the rock was exhumed above the PAZ during Eocene. If the temperature increase (i.e. ∼20 ∘C) in the Paleocene to Eocene was solely driven by gravity loading, the thickness of the ∼1800 m. In addition, the AFT of Aiguá Batholith (38±2.5 Ma; sample U-1) indicates normal re-activation of old Brasiliano/Pan African Shear Zones along of the Paleogene rifts.
Summarizing, thermal models support the possibility that the basement of the Dom Feliciano Belt experienced a first cooling during Ordovician to Permian (500–260 Ma). After, was followed by tectonic activity and exhumation/denudation during the Triassic to Jurassic (260–150 Ma). During the Cretaceous occurred a phase of stagnation, renewed sedimentation which caused subsidence and reheating of parts of the Dom Feliciano Belt. In the Late Cretaceous to recent gave rise to higher exhumation rates (40 Ma).
The thermochronological study from AFT in samples from Uruguay and Southern Brazil divided between three domains of Dom Feliciano Belt namely, West, Central and East can be identified with differentiated exhumation and complex thermal history of the distinct domains. These three domains are formed at the Paleoproterozoic rocks and separated by old reactivated fracture zones. The thermochronological data indicate AFT ages range from 383.4±40.9 to 38±2.5 Ma, which closely matches the range in previous publications. AFT central ages measured in the West Domain range from 383.4±40.9 to 250±21 Ma. In the Central Domain the AFT central ages range from 196.2±14.7 to 130.2±13.3 Ma, and in the East Domain, the AFT central ages range from 262.2±29.9 to 38±2.5 Ma. These data allowed to separate the Western Domain with older ages (> 250 Ma) of the Eastern Domain, which presents younger ages (< 230 Ma).
Based on thermal history modeling, the Western Domain cooled down very fast in the Cambrian in the Taquarembó Terrane, Brazil, and during the Devonian in the Nico Perez Terrane, Uruguay, followed by the Central Domain in the Camaquã Basin, Brazil. The Eastern Domain began to register fast-moderate cooling only from the Ordovician in the Pelotas Batholith, at the same time as occurs reheating in this area. However, in the Western Domain, a very fast period of reheating occurred in the Piedra Alta Terrane, Uruguay. During the Carboniferous-Permian a slow period of cooling is registered in the Western Domain. This phase is assumed to be triggered by the Gondwanide Orogeny and Gondwana II (Brasiliano Orogeny).
Mesozoic time is characterized in the Dom Feliciano Belt by very complex temperature evolution with fast and slow cooling and reheating. The samples of Western Domain show fast cooling in the Triassic, followed by reheating especially the samples just below the Piedra Alta Terrane. During the Jurassic, the East Domain undergoes a slow cooling in the Pelotas Batholith, Brazil, and Cuchilla Dionísio Terrane, Uruguay. The Pelotas Batholith also show a reheating period that begins in the Jurassic and extends until the Oligocene. These thermal histories can be related to the formation of NW-trending grabens and Paraná-Etendeka event. After almost stable conditions up to Miocene times a final very rapid cooling occurred.
In the Eocene (∼40 Ma), the Dom Feliciano Belt registered a very large denudation in the Eastern Domain. Applied from the thermal gradients an overburden of 2640 m can be assumed, suggesting a correlation with the Rio Grande Cone. In addition, indicate normal re-activation of old Brasiliano/Pan African Shear Zones along of the Paleogene rifts.
Data availability.
No data sets were used in this article.
CHG was responsible for all the experimental work and results. CHG and DdPMdA were responsible for the preparation and scientific discussions.
Competing interests.
The authors declare that they have no conflict of interest.
Special issue statement.
This article is part of the special issue "Earth surveillance and space-based monitoring of the environment: integrated approaches". It is a result of the EGU General Assembly 2018, Vienna, Austria, 8–13 April 2018.
Cristiane H. Gomes acknowledges the National Council for Scientific and Technological Development – CNPq for the scholarship programme with the reference 141178/2010-8. The authors acknowledge to CPRM and Votorantin Metal Company for borehole samples, and Project FAURGS/FINEP/CTPETRO 21.01.0310.00 for basement samples. We are grateful for reviews of Farid Chemale Jr. and anonymous reviewer that led to improvements in the manuscript.
Edited by: Silas Michaelides
Reviewed by: two anonymous referees
Almeida, D. P. M., Chemale Jr., F., and Machado, A.: Late to Post-Orogenic Brasiliano Pan-African Volcano-Sedimentary Basins in the Dom Feliciano Belt, Southernmost Brazil, Petrology, 73–130, 2012.
Almeida, F. F. M. and Carneiro, C. D. R.: Origem e evolução da serra do mar, Rev. Bras. Geo., 28, 135–150, 1998.
Almeida, F. F. M., Brito Neves, B. B., and Carneiro, C. D. R.: The origin and evolution of the South American platform, Earth Sci. Rev., 50, 77–111, 2000.
Barboza, E. G., Ros, A. M. L. C. C., and Ayup-Zouain, R.: Cronoestratigrafia da Bacia de Pelotas: uma revisão das sequências deposicionais, Grave, Porto Alegre, 6, 125–138, 2008.
Basei, M. A. S., Frimmel, H. E., Nutman, A. P., and Preciozzi, F.: West Gondwana amalgamation based on detrital zircon ages from Neoproterozoic Ribeira and Dom Feliciano belts of South America and comparison with coeval sequences from SW Africa, in: West Gondwana, Pre-Cenozoic correlations across the South Atlantic region, edited by: Pankhurst, R. J., Trouw, R. A. J., Brito Neves, B. B., and de Wit, M. J., Geological Society, Special Publication, 294, 239–256, 2008.
Bassetto, M., Alkmin, F. F., Szatmari, P., and Mohriak, W. U.: The oceanic segment of the southern Brazilian margim: morpho-structural domains and their tectonic significance, in: Atlantic Rifts and Continental Margins, Geophys. Monogr. Series, 115, 235–259, 2000.
Bitencourt, M. F. and Nardi, L. V. S.: Late- to Post-collisional Brasiliano Magmatism in Southernmost Brazil, Anais da Academia Brasileira de Ciências, 65, 3–16, 1993.
Borba, A. W., Vignol-Lelarge, L., and Mizusaki, A. M. P.: Uplift and denudation of the Caçapava do Sul granitoids (southern Brazil) during late Paleozoic and Mesozoic: constraints from apatite fission-track data, J. South Am. Earth Sci., 15, 683–692, 2002.
Bossi, J. and Campal, N.: Magmatismo y tectônica transcorrente durante el Paleozoico Inferior en Uruguay, in: Paleozoico Inferior de Ibero-América, Extremadura, edited by: Gutiérrez Marco, J. G., Saavedra, J., Rábano, I., Universidad de Extremadura, 343–356, 1992.
Bossi, J., Ferrando, L., Montaña, J., Campal, N., Morales, H., Gancio, F., Schipilov, A., Piñeyro, D., and Sprechmann, P.: Carta Geológica del Uruguay, Escala 1:500 000, 1998.
Campal, N. and Schipilov, A.: The eastern edge of the Rio de la Plata Craton: A history of tangential collisions, P. Int. C Bas., 13, 33–48, 1999.
Castillo Lopes, L. A.: Interpretação Sismoestratigráfica e Geomorfológica Sísmica do Cone de Rio Grande, Bacia de Pelotas, PhD, Programa de Pós-Graduação em Geociências, Porto Alegre, UFRGS, 2009.
Chemale Jr., F.: Evolução geológica do Escudo Sul-rio-grandense, in: Geologia e Estratigrafia do Rio Grande do Sul, Porto Alegre: CIGO/UFRGS, edited by: Holz, M. and De Ros, L. F., 13–52, 2000.
Chemale Jr., F., Ebert, H. D., Luft, J. R., and Mallmann, G.: Evolução tectônica e história térmica da margem SE do Brasil e W da África, Porto Alegre: FAURGS/FINEP/PETROBRAS, 1, 102–210, 2005.
Chemale Jr., F., Mallmann, G., Bitencourt, M. F., and Kawashita K.: Time constraints on magmatism along the Major Gercino Shear zone, Southern Brazil: implications for West Gondwana reconstruction, Gondwana Res., 22, 184–199, 2012.
Cingolani, C., Varela, R, Dalla Salda, L., Bossi, J., Campal, N., Piñeiro, D., and Schipilov, A.: Rb-Sr geochronology from the Río de La Plata craton, South American Symposium on Isotope Geology, Actas, 1, 73–75, 1997.
Cobbold, P. R., Meisling, K. E., and Mount, V. S.: Reactivation of an Obliquely Rifted Margin, Campos and Santos Basins, Southeastern Brazil, AAPG Bull., 11, 1925–1944, 2001.
Contreras, J., Zühlke, R., Bowman, S., and Bechstädt. T.: Seismic stratigraphy and subsidence analysis of the southern Brazilian margin (Campos, Santos and Pelotas basins), Mar. Pet. Geol., 27, 1952–1980, 2011.
Dalla Salda, L., Bossi, J., and Cingolani, C.: The Rio de La Plata cratonic region of South western Gondwana, Episodes, 11, 263–269, 1988.
de Freitas-Brasil, F. A.: Estratigrafia de sequências e processo diagenético: exemplos dos arenitos marinho-rasos da Formação Ponta Grossa, noroeste da Bacia do Paraná, Master Degrau, Programa de Pós-Graduação em Análise de Bacias e Faixas Móveis, UERJ, Rio de Janeiro, 2004.
Della Fávera, J. C.: Fundamentos de Estratigrafia Moderna, Rio de Janeiro, University of Rio de Janeiro State, 263 pp., 2001.
de Oliveira, C. H. E., Jelinek, A. R., Chemale Jr., F., and Bernet, M.: Evidence of post-Gondwana breakup in Southern Brazilian Shield: Insights from apatite and zircon fission track thermochronology, Tectonophysics, 666, 173–187, 2016.
Donelick, R. A.: Crystallographic orientation dependence of mean etchable fission track length in apatite: An empirical model and experimental observations, Am. Mineral., 76, 83–91, 1991.
Donelick, R. A., O'Sullivan, P. B., and Ketcham, R. A.: Apatite fission-track analysis, Rev. Mineral Geochem., 58, 49–94, 2005.
Dumitru, T. A.: Fission-track geochronology in: Quaternary Geochronology: Methods and Applications, AGU Ref. Shelf, 4, 131–159, 1999.
Dunkl, I.: TRACKKEY: a windows program for calculation and graphical presentation of fission track data, Comput. Geosci., 28, 3–12, 2002.
Fernandes, L. A. D. and Koester, E.: The Neoproterozoic Dorsal de Canguçu strike-slip shear zone: Its nature and role in the tectonic Evolution of Southern Brazil, J. Afr. Earth Sci., 29, 3–24, 1999.
Fernandes, L. A. D., Tommasi, A., and Porcher, C. C.: Deforma-pré-cambrien de Rio Grande do Sul (Brésil), Mode de gisement et Feliciano belt, J. South Am. Earth Sci., 5, 77–96, 1995.
Fontana, R. L.: Evidências geofísicas da presença de hidratos de gás na Bacia de Pelotas – Brasil, in: Congresso da Sociedade Brasileira de Geofísica, 1, Rio de Janeiro, Anais, 19–22 August, 234–248, 1989.
Franco-Magalhães, A. O. B., Hackspacher, P. C., and Saad, A. R.: Exumação tectônica e reativação de paleolineamentos no Arco de Ponta Grossa: termocronologia por traços de fissão em apatitas, Rev. Bras. Geoci., 40, 184–195, 2010.
Gallagher, K., Hawkesworth, C. J., and Mantovani, M. S. M.: The denudation history of the onshore continental margin SE Brazil inferred from apatite fission track data, J. Geophys. Res., 99, 18117–18145, 1994.
Gallagher, K., Hawkesworth, C. J., and Mantovani, M. S. M.: Denudation, fission track analysis and long-term evolution passive margin topography: application to the southeast Brazilian margin, J. South Am. Earth Sci., 8, 65–77, 1995.
Gastal, M. C. P., Lafon, J. M., Ferreira, J. F. F., Magro, J. F. U., Remus, M. V. D., and Sommer, C. A.: Reinterpretação do Complexo Intrusivo Lavras do Sul, RS, de acordo com os sistemas vulcano-plutônicos de subsidência. Parte 1: geologia, geofísica e geocronologia (207Pb/206Pb e 206Pb/238U), Rev. Bras. Geoci., 36, 109–124, 2006.
Gaucher, C., Finney, S. C., Poiré, D. G., Valencia, V. A., Grove, M., Blanco, G., Chiglino, L., Pamoukaghlián, K., and Gómez Peral, L.: Detrital zircon ages of Neoproterozoic sedimentary successions in Uruguay and Argentina: Insights into the geological evolution of the Río de La Plata Craton, Precambr. Res., 167, 150–170, 2009.
Gaucher, C., Frei, R., Chemale Jr., F., Frei, D., Bossi, J., Martinez, G., Chiglino, L., and Cernuschi, F.: Mesoproterozoic evolution of the Rio de la Plata Craton in Uruguay: at the heart of Rodinia?, Int. J. Earth Sci., 100, 273–288, 2011.
Gleadow, A. J. W.: Confined fission track lengths in apatite: a diagnostic tool for thermal history analysis, Contrib. Mineral. Petr., 94, 405–415, 1986.
Gleadow, A. J. W. and Lovering, J. F.: Geometry factor for external detectors in fission track dating, Nucl. Tracks Rad. Meas., 1, 99–106, 1977.
Gomes, C. H.: História Térmica das regiões sul e sudeste da América do Sul: implicações na compartimentação geotectônica do Gondwana, Thesis, Universidade Federal do Rio Grande do Sul, Porto Alegre, 2011.
Green, P. F.: The relationship between track shortening and fission track age reduction in apatite, Combined influence of inherent stability, annealing anisotropy, length bias and system calibration, Earth Planet. Sc. Lett., 89, 335–352, 1985.
Gruber, L., Porcher, C. C., Koester, E., Bertotti, A. L., Lenz, C., Fernandes, L. A. D'A., and Remus, M. V. D.: Isotope geochemistry and geochronology of syndepositional volcanism in Porongos Metamorphic Complex, Santana da Boa Vista antiform, Dom Feliciano Belt, Brazil: Onset of an 800 Ma continental arc, JSE, 1, 202–221, 2016.
Hackspacher, P. C., Ribeiro, L. F. B., Ribeiro, M. C. S., Fetter, A. H., Hadler Neto, J. C., Tello, C. A. S., and Dantas, E. L.: Consolidation and breakup of the South American Platform in Southeastern Brazil: tectonothermal and denudation histories, Gondwana Res., 7, 91–101, 2004.
Hallinan, S., Mantovani, M. M., Shukowsky, W., and Braggion Jr., I.: Estrutura do Escudo Sul-Brasileiro: uma revisão através de dados gravimétricos e magnetométricos, Rev. Bras. Geoci., 23, 201–214, 1993.
Hartmann, L. A., Piñeyro, D., Bossi, J., Leite, J. A. D., and Mcnaughton, N. J.: Zircon U-Pb SHRIMP dating of Paleoproterozoic Isla Mala granitic magmatism in the Rio de La Plata Craton, Uruguay, J. South Am. Earth Sci., 13, 105–113, 2000.
Hartmann, L. A., Santos, J. O. S., Cingolani, C., and McNaughton, N.: Two Paleoproterozoic orogenies in the evolution of the Tandilia Belt, Buenos Aires, as evidenced by Zircon U–Pb SHRIMP geochronology, Int. Geol. Rev., 44, 528–543, 2002.
Hiruma, S. T., Riccomini, C., Modenesi-Gauttieri, M., Hackspacher, P. C., and Hadler N. J. C.: Denudation history of the Bocaina Plateau, Serra do Mar, southeastern Brazil: Relationships to Gondwana breakup a passive margin development, Gondwana Res., 18, 674–687, 2010.
Hurford, A. J.: Standardization of fission track dating calibration: Recommendation by the Fission Track Working Group of the I.U.G.S. Subcommission on Geochronology, Chem. Geol., 80, 171–178, 1990.
Hurford, A. J. and Green, P. F.: The zeta age calibration of fission track dating, Chem. Geol., 41, 285–317, 1983.
Janasi, V. A., Freitas, V. A., and Heaman, L. H.: The onset of flood volcanism, Northern Paraná Basin, Brazil: A precise U-Pb baddeleyite/zircon age for a Chapecó-type dacite, Earth Planet. Sc. Lett., 302, 147–153, 2011.
Karl, M., Glasmacher, U. A., Kollenz, S., Franco-Magalhães, A. O. B., Stockli, D. F., and Hackspacher, P. C.: Evolution of the South Atlantic passive continental margin in southern Brazil derived from zircon and apatite (U-Th-Sm)/He and fission-track data, Tectonophysics, 604, 224–244, 2013.
Keeley, M. L. and Light, M. P. R.: Basin evolution and prospectivity of the Argentine continental margin, J. Petrol. Geol., 16, 451–464, 1993.
Ketcham, R. A., Donelick, R. A., and Carlson, W. D.: Variability of Apatite Fission-Track Annealing Kinetics: III. Extrapolation to Geologic Time Scales, Am. Mineral., 84, 1235–1255, 1999.
Ketcham, R. A., Donelick, R. A., and Donelick, M. B.: Aftsolve: a program for multikinetic modelling of apatite fission-track data, Geo. Mater. Res., 2, 1–32, 2000.
Kollenz, S.: Long term landscape evolution, cooling and exhumation history of the South American passive continental margin in NE Argentina & SW Uruguay, Dissertation, Fakultät für Chemie und Geowissenschaften, Institut für Geowissenschaften, 2015.
Laslett, G. M., Gleadow, A. J. W., and Duddy, I. R.: The relationship between fission track length and track density in apatite, Nucl. Tracks Radiat. Meas., 9, 29–38, 1982.
Luft, F. F., Luft Jr., J. L., Chemale Jr., F., Lelarge, M. L. M. V., and Ávila, J. N.: Post-Gondwana break-up record constraints from apatite fission track thermochronology in NW Namibia, Radiat. Meas., 39, 675–679, 2005.
Mcloughln, S.: The breakup history of Gondwana and its impact on pre-Cenozoic floristic provincialism, Aust. J. Bot, 49, 271–300, 2001.
McDougall, I. and Harrison, T. M.: Geochronology and Thermochronology by the 40Ar∕39Ar Method, 2nd ed., Oxford, Oxford University Press, 269 pp., 1999.
Meisling, K. E., Cobbold, P. R., and Mount, V. S.: Segmentation of an obliquely rifted margin, Campos and Santos basins, southeastern Brazil, AAPG Bull., 85, 1903–1924, 2001.
Melo, M. S., Riccomini, C., Hasui, Y., Almeida, F. F. M., and Coimbra, A. M.: Geologia e evolução do sistema de bacias tafrogênicas continentais do sudeste do Brasil, Rev. Bras. Geoci., 15, 193–201, 1985.
Milani, A. J.: Evolução tectono-estratigráfica da bacia do paraná e seu relacionamento com a geodinâmica fanerozóica do gondwana sul-ocidental, PhD Tese, CPGEO/UFRGS, 1997.
Milani, E. J.: Geodinâmica fanerozóica do Gondwana sul-ocidental e a evolução geológica da Bacia do Paraná, in: Geologia do Rio Grande do Sul, Porto Alegre: CIGO/UFRGS, 275–302, 2000.
Moulin, M., Aslanian, D., and Unternehr, P.: A new starting point for the South and Equatorial Atlantic Ocean, Earth Sci. Rev., 98, 1–37, 2010.
O'Sullivan, P. B. and Parrish, R. R.: The importance of apatite composition and single-grain ages when interpreting fission track data from plutonic rocks: a case study from the Coast Ranges, British Columbia, Earth Planet. Sc. Lett., 132, 213–224, 1995.
Oyhantçabal, P., Siegesmund, S., and Wemmer, K.: The Rio de la Plata Craton: a review of units, boundaries, ages and isotopic signature, Int. J. Earth Sci., 100, 201–220, 2010.
Paim, P. S. G., Chemale Jr. F., and Wildner, W.: Estágios evolutivos da Bacia do Camaquã (RS), Ciência e Natura, 36, 183–193, 2014.
Passarelli, C. R., Basei, M. A. S., Wemmer, K., Siga Jr., O., and Oyhantçabal, P.: Major shear zones of southern Brazil and Uruguay: escape tectonic in the eastern border of Rio de La plata and Paranapanema cratons during the Western Gondwana amalgamation, Int. J. Earth Sci., 100, 391–414, 2010.
Pinto, V. M., Hartmann, L. A., Mcnaughton, N. J., and Wildner, W.: Zircon U-Pb geochronology from the Paraná bimodal volcanic province support a brief eruptive cycle at ∼135 Ma, Chem. Geol., 281, 93–102, 2011.
Philipp, R. P. and Machado, R.: Suítes graníticas do batólito Pelotas no Rio Grande do Sul: petrografia, tectônica e aspectos petrogenéticos, Rev. Bras. Geoci., 31, 257–266, 2005.
Philipp, R. P., Lusa, M., and Nardi, L. V. S.: Geochemistry and petrology of dioritic, tonalitic and trondhjemitic gneisses from Encantadas Complex, Santana da Boa Vista, southernmost Brazil, a Paleoproterozoic continental-arc magmatism, An. Acad. Bras. Ciênc, 80, 1–14, 2008.
Philipp, R. P., Pimentel, M. M., and Chemale Jr., F.: Tectonic evolution of the Dom Feliciano Belt in Southern Brazil: Geological relationships and U-Pb geochronology, Braz. J. Geol., 46, 83–104, 2016.
Preciozzi, F. L., Peel, E., Bettucci, L. S., Basei, M. A. S., Aubet, N., and Peçoits, E.: El Terreno Piedra Alta: Una unidad geotectonica Paleoproterozoica juvenil en el Craton del Rio de la Plata (Uruguay), South American Symposium on Isotope Geology, 1, 20–26 July, 1999.
Raab, M. J., Brown, R. W., Gallagher, K. Carter, A., and Weber, K.: Late Cretaceous reactivation of major crustal shear zones in northern Namibia: Constraints from apatite fission track analysis, Tectonophysics, 349, 75–92, 2002.
Ramos, V. A.: The tectonics of the central Andes. in: Processes in continental lithospheric deformation, Geol. Soc. Am. Spec. Pap., 218, 31–54, 1988.
Rapela, C. W., Fanning, C. M., Casquet, C., Pankhurst, R. J., Spalletti, L., Poiré, D., and Baldo, E. G.: The Rio de la Plata Craton and the adjoining Pan-African/brasiliano terranes: Their origin sand incorporation into south-west, Gondwana Res., 20, 673–690, 2011.
Riccomini, C., Turcq, B., and Martin, L.: The colônia astrobleme. in: ABEQUA/INQUA, International Symposium on global changes in South America during the Quaternary: past, present and future, São Paulo, 14 pp., 4–8 September, Excursion Field Guide, 1989.
Saalmann, K., Gerdes, A., Lahaye, Y., Hartmann, L. A., Remus, M. V. D., and Laufer, A.: Multiple accretion at the eastern margin of the Rio de La Plata craton, the prolonged Brasiliano orogeny in southern most Brazil, Int. J. Earth Sci., 100, 355–378, 2011.
Salamuni, E., Ebert, H. D., and Hasui, Y.: Morfotectônica da bacia sedimentar de Curitiba, Rev. Bras. Geoci., 34, 469–478, 2003.
Santos, J. O., Hartmann, L. A., Bossi, J., Campal, N., Schipilov, A., and McNaughton, N. J.: Duration of the Trans-Amazonian Cycle and its correlation within South America based on U-Pb SHRIMP geochronology of the La Plata craton, Uruguay, Int. Geol. Rev., 45, 27–48, 2003.
Siqueira-Ribeiro, M. C., Hackspacher, P. C., Ribeiro, L. F. B., and Hadler Neto, J. C.: Evolução Tectônica e Denudacional da Serra do Mar (SE/BRASIL) no limite entre o Cretáceo Superior e Paleoceno, utilizando análises de Traços de Fissão e U-TH/HE em Apatitas, Rev. Bras. Geom., 12, 3–14, 2011.
Tello, C. A. S., Hackspacher, P. C., Hadler Neto, J. C., Iunes, P. J., Ribeiro, L. F. B., and Paulo, S. R.: Recognition of cretaceous, Paleocene and Neogene tectonic reactivation through apatite fission track analysis in Precambrian areas of 10 southeast Brazil: association with the opening of South Atlantic Ocean, J. South Am. Earth Sci., 15, 765–774, 2003.
Teixeira, W., Renne P., Bossi, J., Campal, N., and Dagrella Filho, M.: Ar40∕Ar39 and Rb∕Sr geochronology of the Uruguay Dike Swarm, Rio de la Plata Craton, Precambr. Res., 93, 153–155, 1999.
Tomazelli, L. J. and Villwock, J. A.: O cenozóico no Rio Grande do Sul: geologia da planície costeira, in: Geologia do Rio Grande do Sul, edited by: Holz, M. and De Ros, L. F., Porto Alegre: IG/UFRGS, 375–406, 2000.
Tinker, J., De Wit, M., and Brown, R. W.: Mesozoic exhumation of the southern Cape, South Africa, quantified using apatite fission track thermochronology, Tectonophysics, 455, 77–93, 2008.
Zalán, P. V., Wolffs, S., Conceição, J. C. J., Appi, V. T., Astolfi, M. A. M., and Marques, A.: The Paraná Basin, in: Interior Cratonic Basins, edited by: Leighton, M. W., Kolata, D. R., Oltz, D. F., and Eidel, J. J., AAPG, 51, 681–708, 1990.
Zerfass, H., Lavina, E. L., Schultz, C. L., Garcia, A. J. V., Faccini, U. F., and Chemale Jr., F.: Sequence stratigraphy of continental Triassic strata of southernmost Brazil: a contribution to southwestern Gondwana palaeogeography and palaeoclimate, Sediment Geol., 161, 85–105, 2003.


SQuare is a creative agency offering consultancy in every way possible to companies that need a unique and refreshing perspective on their brands & live communication. We provide Concept - Creative management & total production on a global scale.
Er zijn (nog) geen reviews over SQuare. Ben jij de eerste die er één deelt?


Here are a few good reasons why the Original Equipment Manufacturers (OEMs) choose the ORIGINAL AccuTorq®:• Swedish Spring Steel. The BEST raw materials, specially heat-treated, make AccuTorq® the most accurate torque socket in the world.• Patented Strobe Marks. Patented AccuTorq® "strobe marks" stop turning at precisely the correct torque EVERY time. There is NO "guess" work and no recalibration.• Solid One-piece. Solid one-piece construction of AccuTorq® automotive and commercial truck sockets eliminates the wide torque variances unavoidable with socket extensions and adaptors.• DEEP-well Sockets. AccuTorq® provides DEEP-well sockets for those special applications where regular socket depth is just not enough to get the job done.• LIFETIME WARRANTY. Accutorq® ultrasonic inspection of EACH socket and it's ISO 9001 Quality Certification of manufacturing processes make it possible for each AccuTorq® socket to come with a LIFETIME warranty.


Interactive Plan-a-Gift™ will recommend the best gift plan to meet your individual needs based on your age, goals and assets, and will help Kennedy Krieger Foundation at the same time.
Your goal What do you want to accomplish with your gift? Provide immediate support for Kennedy Krieger and take a tax deduction.
Establish a stream of income for myself and future support for Kennedy Krieger.
Provide a stream of income for Kennedy Krieger now and tax-free support for my loved ones later.


Since October 2018, the Mississippi River has been running high, thanks in part to heavier-than-usual rainfall across its northern and central stretches.
And when the water flows high on the most powerful river in the U.S., local residents and industries take notice. Fishermen fret the high January waters could mean a poor brown shrimp season ahead. Shippers using barges to haul grain bemoan headaches caused by fast-flowing waters and the river-traffic restrictions that follow. And federal agencies like the Army Corps of Engineers start inspecting levees daily and barring digging within 1,500 feet of the embankments built to protect river-side residents against flooding.
But in the swamps of the Atchafalaya Basin, roughly a million acres of bayous, lakes, and wetlands that span upwards from the Gulf of Mexico for 140 miles into Louisiana, there's one thing that hasn't responded as it should to the rising waters: construction of Energy Transfer's Bayou Bridge pipeline.
That's according to a legal motion filed today by attorneys for a coalition of fishing industry representatives and environmental groups, asking a federal court to pause construction of the pipeline and review its permit.
Despite the fact that the company's Army Corps of Engineers permit says construction must halt under high water conditions, Energy Transfer, which co-owns the pipeline along with its affiliates, has pressed on with pipeline construction — something the builder promised the court it would not do, according to the motion filed in a Louisiana federal court today.
The company has been using excavators to dig amid high waters without proper environmental controls, destroyed old-growth cypress trees, and managed sediment so poorly that "it's placing the people of Louisiana at risk by reducing the effectiveness of the Basin as a buffer against dangerous floodwaters," according to the environmental groups.
Outside New Orleans, flood gauges first crossed the "high water" mark — 11 feet at the Carrolton Station, according to the Army Corps — three months ago, and have remained consistently over 11 feet since mid-December.
DeSmog's Julie Dermansky has visited the Bayou Bridge site over the course of the past year, accompanying Wilson, who has been documenting construction practices that the groups argue clearly violate the conditions of Bayou Bridge's permits — including an early October visit, when Dermansky took photos and reported as the waters began to rise.
The plaintiffs in the case, a group that includes Wilson, say they've repeatedly provided the Army Corps of Engineers with evidence of the alleged violations but that the Corps has failed to act.
Last year, the coalition of Bayou Bridge opponents had asked the same judge to pause construction because of insufficiencies in the pipeline's permit from the Army Corps of Engineers and the company's plans to replace old-growth cypress trees up to 1,000 years old with smaller, younger trees.
A federal judge granted that motion, citing irreversible harm, but the ruling was reversed by the Fifth Circuit in a split 2-1 opinion. The Fifth Circuit found that since there were no trees similar to the old-growth cypress available as replacements, state law allowed the company to substitute younger trees instead.
During that fight, the pipeline company had used the permit's prohibition on construction work during "high water" events to defend itself.
But construction, the new filing contends, did not stop.
Wilson and other environmentalists have provided the Army Corps of Engineers with documentation of continued construction and other permit violations – but the Corps has not acted, according to the lawsuit.
Bobcats, alligators, aquatic rodents known as nutria, bald eagles, and more than a hundred fish species all call the Atchafalaya Basin, which is larger if perhaps less well-known than the Florida Everglades, home.
A spokesperson for Energy Transfer did not immediately reply to a request for comment.
In 2017, Louisiana's governor John Bel Edwards said he was endorsing the pipeline in part because environmental laws would be strictly enforced.
The new lawsuit argues that the Army Corps of Engineers showed the pipeline company too much deference and failed to enforce federal laws designed to protect the environment.


text:
Houston takes top spot among markets for residential property investment
By Katherine Feser on March 25, 2015 at 11:38 AM
Photo: Gary Coronado / Houston Chronicle
No. 1: Houston
No. 2: Austin-Round Rock
Photo: HARRY CABLUCK / AP
No. 3: Dallas-Plano-Irving
Photo: Brandon Wade / SPECIAL/BRANDON WADE
No. 4: Denver-Aurora
Photo: Marc Piscotty / Associated Press
No. 5: Orlando
Photo: Phelan M. Ebenhack / Associated Press
No. 6: San Jose-Sunnyvale-Santa Clara, Calif.
Photo: Jeff Chiu / Associated Press
No. 7: Seattle-Bellevue-Everett
Photo: JANE WOOLDRIDGE / MCT
No. 8: Oakland-Fremont-Hayward, Calif.
No. 9: Miami-Miami Beach-Kendall
Photo: Joe Raedle / Getty Images
No. 10: Portland-Vancouver-Beaverton
Photo: Don Ryan / Associated Press
Houston topped a list of the best cities for residential real estate investments as pent-up demand and a growing economy overshadowed the cloud of lower oil prices, a new report showed.
HomeVestors, the Dallas-based company that runs the "We Buy Ugly Houses" franchise, and Local Market Monitor, a national real estate forecasting firm, identified markets where home prices are likely to increase at a good rate over the next few years. It looked at markets with above-average population growth (4 percent or better), current job rate growth of 2 percent or better and low unemployment.
The nation's economy is growing at the fastest rate since 2000, which translates into a good market for residential investments either for rent or resale.
"The Top 10 markets for real estate investment all have a common thread: a fast growing economy, which means more jobs and more renters," Ingo Winzer, president and founder of Local Market Monitor, said in an announcement. "This also means that rent and property values will be increasing in many markets because housing construction has been at very low levels for years and can't possibly catch up with the increased demand."
Houston, Austin and Dallas took the top three slots, with Denver and Orlando rounding out the top five.
"Texas continues to be a sure bet when it comes to real estate investing. Lower oil prices may slow some areas, but the diversified economy and pent up demand for real estate will help to mitigate the impact on rental markets," David Hicks, HomeVestors co-president, said in an announcement. "Places like Austin and Dallas have rapidly growing technology and financial sectors that make the oil slump less significant."
All top five markets have a median home price below $300,000.
San Jose and Oakland ranked Nos. 6 and 8, respectively.
"California has higher home prices, but the state is growing again, both in jobs and population. Because most of these markets are no longer underpriced, investors in these markets are likely to see more of their gain come from price appreciation and less from a long-term rental stream," HomeVestors co-president Ken Channel said.
Growing tech sectors and a quality of life helped propel Seattle to No. 7 and Portland to No. 10, while a rapidly growing population and high rents took Miami to No. 9.

redpajama_set_name: RedPajamaCommonCrawl


Dreaming of building a new home, customizing every detail to fit your own tastes and lifestyle? Even when you know exactly what you want from your dream home, making it happen can be an overwhelming journey. Dozens of builders and neighborhoods, hundreds of floor plans, and thousands of design choices and upgrades face you. These are all important choices that culminate to create the home of your dreams.
A builder's sales rep works for and represents the builder. TheColumbusTeam Buyer Specialist works exclusively for YOUR best interests. We research and present all options, and accompany you through the maze of choices during construction. TheColumbusTeam knows the builders, the neighborhoods, and knows how to negotiate what you want within a comfortable budget.
We'll meet you, lay out your many choices & floor plans in one central location. No running around to dozens of builders and construction sites! Choose your favorites and we'll take you to view them. When it's time to negotiate, your Buyer Specialist can make recommendations and help resolve issues, creating an exciting and enjoyable new build experience!
TheColumbusTeam builds 3-5 homes with each builder every year. By allowing us to represent you, you become a "preferred buyer" to that builder. You are not a one-time customer. Allow us to fulfill your needs and move you up to "preferred buyer" status.
Contact us to set up your new build appointment today!
Take a look at the many locations and builders available by visiting our family member of web sites: www.NewBuildMatch.com… or call us, we'd be happy to assist you!
Contact The Columbus Team about Building your Home!


Disney Cruise Line – Dizney Wizard – Nicole!
What do you love most about Disney Castaway Cay, Disney's private island in the Bahamas? Is it the gorgeous white-sand beaches? Sliding and splashing into turquoise waters from Pelican Plunge? The peace and tranquility of Serenity Bay, the adult-exclusive beach? Or, is it exploring the natural beauty of the island pedaling bikes with family?
Well, the members of Cruise Critic have spoken and apparently love all of the above – and everything else Disney's magical island has to offer!
For the second year in a row, Disney Castaway Cay has been named the Top Cruise Line Private Island in the annual Cruise Critic Cruisers' Choice Destination Awards. Also for the second year in a row, Castaway Cay was the most highly rated Caribbean island overall among reviewers, beating out all other Caribbean islands!
These awards are based exclusively on firsthand feedback from cruisers themselves, gathered from reviews posted to the Cruise Critic website over this past year. Cruise Critic, is one of the leading cruise review and information sites, offering a resource for travelers and hosting the world's largest online cruise community.
If you would like to learn more about what all Castaway Cay has to offer, contact me today!
Discover Rugged Adventures and Natural Wonders in Iceland on a Disney Cruise!
As the Disney Magic tours Europe this summer and next, Iceland is one of the amazing destinations Disney Cruise Line is taking Guests to explore. With ruggedly beautiful terrain, iconic geothermal pools and an abundance of whales swimming just off the coast, it's the perfect spot for adventure-seeking families.
Akureyri and Reykjavik are both ports of call on the 11-night Norwegian Fjords cruise this summer. An overnight call on Reykjavik gives Guests three back-to-back days in this incredible land of fire and ice. Then, Disney Cruise Line returns to Iceland in 2018 with two days in Reykjavik on our 10-night Norwegian Fjords cruise.
See what rugged adventures and natural wonders await you in Iceland onboard a Disney Cruise in this video!
Posted on July 13, 2017 Categories Disney Cruise LineLeave a comment on Discover Rugged Adventures and Natural Wonders in Iceland on a Disney Cruise!
Stan Lee Assembles Super Heroes for Disney Cruise Line's Marvel Day at Sea!
You and your family can unleash your inner Super Hero this fall on the inaugural sailings of Marvel Day at Sea with Disney Cruise Line on select 7-night cruises from New York City. Check out this video as Captain America, Iron Man and more get the call from a Marvel legend.
Marvel Day at Sea kicks off in October on select 7- and 8-night cruises from New York City. The excitement continues on select 5-night voyages from Miami departing January through April.
Posted on June 8, 2017 June 8, 2017 Categories Disney Cruise LineTags Disney Cruise Line, Marvel Day at SeaLeave a comment on Stan Lee Assembles Super Heroes for Disney Cruise Line's Marvel Day at Sea!
Disney Cruise Line Announces TWO NEW SHIPS!
Disney Cruise Line is proud to announce plans to build two additional cruise ships, each of them showcasing the immersive family entertainment, enchanting storytelling and unparalleled service that only Disney can deliver.
This is some very exciting news! I can only imagine what the Imagineering team can come up with for these two ships after seeing what they have already came up with for the original four ships. I am really hoping they come up with something even more unique that what the other ships already have!
To find out more information about the Disney Cruise Line, click here!
Posted on March 7, 2016 Categories Disney Cruise LineLeave a comment on Disney Cruise Line Announces TWO NEW SHIPS!
You can view your reservation at Disney Cruise Line where you can pre-book your Shore Excursions, Palo reservation and Spa treatments. If you have children under age 18 in your party, you can pre-register them for the kid's programs.
There are four options to choose: Shore Excursions, Dining, Vista Spa and Children's Programming. Within each category you can arrange your schedule of events. Changes and cancellations of your plans are just a click away.
One important part of pre-booking is to schedule your Port Arrival Time. Disney Cruise Line offers staggered arrival times to help prevent congestion in the port, so you will need to pick from a list of available times.
When you view your reservation, you'll see the cruise itinerary. If you've chosen excursions, Dining and/or Spa treatments, you'll see that information listed on the day that you selected. It's in an easy to print out format that you can take with you on your vacation.
While you will receive a packet of documents prior to your cruise, you can also access and print the Embarkation form, Payment Authorization form, Cruise Contract, Medical Information Form and Minor Authorization form.
Reservations are filled on a first come, first serve basis and some excursions, reservations and events have capacity limits. I encourage you to make reservations early to avoid any disappointment.
**PLEASE NOTE: Shore excursions are final and non-refundable once you're within 3 days of your sail date.** Guests who choose not to pre-reserve shore excursions prior to their cruise may stop by the ship's Shore Excursion Desk, located on Deck 3, on embarkation day, to check availability and purchase excursions. Due to limited availability, some excursions may not be available.
All guests with pre-reserved shore excursions will receive excursion tickets delivered to their stateroom on embarkation day. Payment for confirmed excursions will be billed directly to the guest's shipboard account. Advance payment is not required or accepted.
Disney Cruise Line uses "bulk air" when making flight assignments for their guests. Flights are not finalized until 30 days prior to your arrival and they DO NOT make your seat assignments. Once you have the flight information, you need to contact the airline to have your seating requests noted.
Note that in accordance with airline policies, children under age 2 are not provided with air unless it is specifically requested. Disney Cruise Line will consider the infant to be a "lap child." Children age 2 and up are required to have a seat on the plane.


text:
Presidents Rumen Radev and Salome Zourabichvili Discussed Bulgaria's and Georgia's Readiness to Boost Bilateral Trade after the Coronavirus
The development of the transport, energy and digital corridors in the Black Sea region will be particularly important after the end of the economic stagnation caused by the COVID-19 pandemic. Therefore it is essential that the work on the implementation of the joint Bulgarian-Georgian projects be continued. This was the common stance shared by the Presidents of Bulgaria and Georgia Rumen Radev and Salome Zourabichvili, who held a video-conference call on the initiative of the Georgian side, the presidential press office reported.
The two were unanimous that in the current crisis a balance should be struck between the healthcare measures and the timely implementation of social and economic measures. Bulgaria and Georgia report low morbidity and mortality rate. However, it is necessary that the COVID-19 testing should cover a greater number of groups of the population, which will reveal a clear picture of the epidemic and will make it possible to make adequate decisions for restricting its spread and for a quicker economic recovery, Rumen Radev said.
The two presidents shared the stance that the fight against the coronavirus requires the countries' joint efforts and solidarity. After overcoming the adverse economic effects, caused by the pandemic, it is essential to ensure regional cooperation which would create favorable conditions for boosting bilateral trade and investments, Rumen Radev said.
The Bulgarian Head of State highlighted our country's support for Georgia's sovereignty and territorial integrity, and also for its European and Euro-Atlantic integration. Georgia is the EU's strategic partner in improving the security of the energy supplies to the Black Sea region, President Rumen Radev further said.
Source Novonite.com
Tags:BulgariaCOVID-19ExportGeorgiaIMPORTtrade
Copyright © 2020 BCCCI. All rights reserved.


text:
Jerrod Niemann
Jerrod Lee Niemann (born in Harper, Kansas) is an American country music artist. Active since 2001, he has recorded two independent albums. In 2006, he signed to Category 5 Records and charted with the single "I Love Women (My Momma Can't Stand)". He has also co-written three singles for Garth Brooks: the Chris LeDoux tribute "Good Ride Cowbo… Read More
High Valley
Darryl Worley
Diamond Rio
Stations With Jerrod Niemann
Jerrod Niemann Radio
Plays Jerrod Niemann along with similar artists like:
Lee Brice, Kane Brown, Diamond Rio, Chris Lane, Little Big Town…
Billboard's 100 Best Songs Of 2010
Billboard's 100 Most Popular Songs of 2010!
Far East Movement, Drake, Jay Sean, OneRepublic, Selena Gomez & The Scene, Ni…
Listen to some of country musics top artists.
Dierks Bentley, Kip Moore, Logan Tudeen, Carrie Underwood, George Strait, Lady An…
Plays Country music that veers a bit off the mainstream path.
Jerrod Niemann, Keith Anderson, Jamey Johnson, Tom Petty, Alison Krauss, Brantley…
Montgomery Gentry Radio
Plays Montgomery Gentry along with similar artists like:
Brooks & Dunn, Jamey Johnson, Terri Clark, Colt Ford, Eli Young Band…
Diamond Rio Radio
Plays Diamond Rio along with similar artists like:
The Judds, Faith Hill, Rascal Flatts, Jason Aldean, Lee Ann Womack…
Jason Michael Carroll Radio
Plays Jason Michael Carroll along with similar artists like:
Chris Cagle, Eric Paslay, Jack Ingram, Pat Green, Aaron Watson…
Joe Nichols Radio
Plays Joe Nichols along with similar artists like:
Craig Morgan, Zac Brown Band, Randy Travis, Jason Michael Carroll, Jo Dee…
George Strait Radio
Plays George Strait along with similar artists like:
Brooks & Dunn, Don Williams, Daryle Singletary, Lonestar, Pam Tillis…
From Jerrod Niemann
Drink To That All Night
What Do You Want
Shinin' On Me
Lover, Lover
But I Do
One More Drinkin' Song
The Buckin' Song


Mars is the number one place in the solar system where we really want to go.
Recently, during the 67th annual International Astronautical Congress ni Guadalajara Mexico, Elon Musk, the head of Tesla Motors and SpaceX announced that not only are humans going to travel to Mars in the near future, but we are going to establish a colony on the surface of the red planet where people will live.
However, all of this isn't new according to 'Secret Space Program whistleblower Corey Goode who released a statement detailing human activity on Mars, saying that mankind ahs been on the surface of the red planet for a long, long time.
Strangely, he isn't the first, or only one to have said that.
Many people have stated that these 'accusations' aren't new, and there are documents (WikiLeaks) which argue that human and alien collaborations have been around for quite some time.
But doesn't that sound crazy? Well, he isn't the only one to have said it, and if we go ahead and take a look at a statement from Senator Daniel K. Inouye, we will realize just how profound this subject really is.
"During my tenure in the Navy, we discovered that the Germans had been inventing space technology since the early 20th century." —William Tompkins.
The above statement from Tompkins corroborates comments made by Corey Goode which have been tagged as 'ludicrous' by many.
According to Tompkins, three are declassified documents that show German space-travel technology. He even claims to have worked within extremely classified think thanks, which created weapons for aerospace companies.
In addition to Goode, a former NASA employee claimed there were secret manned missions to Mars over 20 years ago.
In addition to the above, a former Marine claims to have even WORKED on Mars.The retired officer only known as Captain Kaye (pseudonym), said that not only have humans made it to Mars in the past, we have developed a secret space program and flotilla that operates in space.
According to the former Marine, he was posted on the red planet for years and his mission was to protect the five human colonies from indigenous life forms on Mars. According to Captain Kaye, not only did he spend years on Mars, but he also served aboard a giant space carrier for three years.
Reading the above statement and comparing it to what Senator Daniel K. Inouye makes you really wonder if all of the above is possible.
Richardson, Texas, October 13, 2016 – On Tues, Oct. 11th President Barack Obama wrote an Opinion Editorial via CNN.com announcing to the citizens of the United States that, "America has set a clear goal to send humans to Mars by the 2030s…we do what's possible before anyone else." The problem here is that during a Nov. 2015 video interview with Gaia.com, whistleblower Corey Goode from the US Secret Space Program (SSP) said, "There are humans already on Mars, and it's been colonized." In Dec. 1986, Goode was recruited into SSP – UNSAP (Un-Acknowledged Special Access Programs) under Project Solar Warden. He was assigned to a research vessel in space to study the solar system from Dec. 1986 – Dec. 2007.
Is Trump Trying to Lose the Election to Hillary Clinton on Purpose?


text:
Influence of sodium on the properties of sol-gel derived hydroxyapatite powder and porous scaffolds
Sopyan, Lis and Pusparini, Erlani and Subramaniam, Ramesh T. and Tan, Chou Yong and Ching, Yernchee and Wong, Yinhow and Zainal Abidin, Nor Ishida and Chandran, Hari and Ramesh, S. and Bang, Lethi (2017) Influence of sodium on the properties of sol-gel derived hydroxyapatite powder and porous scaffolds. Ceramics International, 43 (15). pp. 12263-12269. ISSN 0272-8842
PDF (Scopus) - Supplemental Material
Official URL: http://www.sciencedirect.com/science/article/pii/S...
This study investigates the properties of sol-gel derived sodium (Na)-doped hydroxyapatite (HA) powder. Different amounts of Na (1, 5, 10 and 15 mol%) were prepared and the sintered bodies were characterized to determine the current phases, microstructural evolution and mechanical properties. X-ray diffraction analysis reveals that a phase pure HA of crystallite sizes, which varied from 35 nm to 65 nm, was obtained in the synthesized powder after calcining from 500 °C to 1000 °C. Scanning electron microscopy examination shows evidence of larger particle sizes, particularly in samples that contain higher amounts of Na concentration. The resultant powders were subsequently used to prepare porous NA-doped HA bodies through a polymeric sponge method. The addition of 5% Na resulted in a porous body with 27% porosity and was beneficial in enhancing the compressive strength of HA 17-fold compared with undoped HA. The prepared scaffold also shows suitable pore interconnectivity with pore sizes that vary between 100 and 300 μm which is suitable for use as porous bone substitutes.
Porous hydroxyapatite; Sodium doping; Mechanical properties
T Technology > TA Engineering (General). Civil engineering (General) > TA164 Bioengineering
T Technology > TA Engineering (General). Civil engineering (General) > TA401 Materials of engineering and construction
PROF. DR. IIS SOPYAN


CMJ's Patrice Whiffen has a chance to catch up with country music artist, Denny Strickland!
Country music newcomer, Denny, talks about his new single "Swerve On." He also talks about his start in country music, and how fans can connect with him.
To check out more about Denny, or to purchase his music, click here!
Check out the exclusive interview with Denny Strickland, here!


text:
Read Next:	Ben Platt On How His Netflix Series 'The Politician' Is a Premonition of College Cheating Scandal
Cohen stays atop 'Hill'
Scribe inks TV pact, penning 'Tropic' for the bigscreen
By Michael Fleming
Michael Fleming
Film Editor, Deadline Hollywood @deadlinemike	FOLLOW
Michael's Most Recent Stories
Peter Bart, Michael Fleming Double Take: Film Flops Negate Star Power, Franchise Potential
Peter Bart and Michael Fleming Face Off in New Column
Castle Rock options 'Playing Joe'
Comedy scribe Etan Cohen has made a seven-figure overall deal with Twentieth Television that keeps him on as a writer and co-exec producer of "King of the Hill" for two seasons and will allow him to create a pilot.
Cohen has also made two scripting deals on comedies to be directed by Jay Roach and Ben Stiller.
The deal comes as Fox nears a 2004 production start on "3001," the live-action comedy feature that Cohen scripted with "King of the Hill" creator Mike Judge. Judge will direct the pic, about a regular guy who wakes up 1,000 years in the future and finds the world so dumbed down that he is its smartest inhabitant.
Cohen is now writing "Tropic Thunder," a DreamWorks comedy that Stiller plans to star in, direct and produce through his Red Hour Films banner.
"It is about the making of a big-budget war movie where everything that can go wrong does, and where the actors end up becoming the commandos they are playing," Cohen said.
Cohen has aligned with "Utopia Street," a project that Roach's Everyman Films has been developing. Cohen has been set to rewrite a script by Adam McKay. The comedy is about a newcomer to an idyllic suburban community who is turned off by his next-door neighbor's aggressive socializing.
The ICM-repped Cohen began his comedy career with Judge. Cohen was a Harvard freshman majoring in Yiddish when Judge changed the course of the frosh's destiny by agreeing to buy segments Cohen scripted for the renegade MTV animated show "Beavis and Butt-Head." Cohen was at a seminary in Israel when he discovered that Judge would use his story about how Beavis and Butt-Head mistook a hard-core feminist rally for a brothel. The incident convinced Cohen that comedy was his true calling.
Beavis & Butt-head
Mike Judge
More Scene
Sharon Stone is back. And after famously serving as amfAR's Global Campaign Chair for 15 years, she's taken on a new role as advocate for brain-aging diseases that disproportionally affect women. Only one third of Alzheimers patients are men, for instance. And don't even get Stone started on strokes. "This is why I do it: [...]
Rob Epstein and Jeffrey Friedman Revisit the Making of Their 1989 Landmark AIDS Doc "Common Threads"
It's been 30 years since the release of the Oscar-winning documentary "Common Threads: Stories From the Quilt," but directors Rob Epstein and Jeffrey Friedman remember when they decided to make the film like it was yesterday. The two were at the 1987 March on Washington for Lesbian and Gay Rights when they saw the massive [...]
Jerry Seinfeld and Eddie Murphy Talk Stand-Up, Stardom and Reuniting for 'Comedians in Cars Getting Coffee'
In July 1976, Jerry Seinfeld and Eddie Murphy were rising comics, launching their stand-up careers at the Comic Strip in New York City. In fact, the two started at the famed comedy club the same week. "[Seinfeld] was always the funniest. He had his show down, he was polished, he had it all down before [...]
Billy Eichner, Seth Rogen Recall Meeting Beyoncé for the First Time at 'The Lion King' Premiere
Billy Eichner and Seth Rogen may co-star in the new "The Lion King" with Beyoncé, but they didn't meet Queen Bey until the world premiere of the movie earlier this month in Hollywood. "She was really lovely," Eichner told me when he and Rogen sat down for this week's episode of "The Big Ticket," Variety [...]
Ben Platt On How His Netflix Series 'The Politician' Is a Premonition of College Cheating Scandal
Ryan Murphy asked Tony winner Ben Platt to star in his first Netflix series "The Politician" in summer 2017, after watching the Broadway prodigy perform on stage in "Dear Evan Hansen" that same year. Murphy and Platt's meeting pre-dated the headline-dominating college admissions scam by nearly two years, but the dark comedy, which debuts Sept. [...]
David Crosby Says New Documentary 'Remember My Name' Is Like 'Being Naked in Public'
"It's not easy. It's hard being naked in public," David Crosby, the legendary troubadour of classic rock, reflected at Tuesday night's New York City premiere of "David Crosby: Remember My Name." "I don't know what to do here. There's no guitars, no drums," he laughed. Directed by newcomer A.J. Eaton and produced by the legendary [...]
The Ultimate Guide to 2019 Comic-Con Parties and Activations
Hollywood is heading down the California coast to San Diego because It's time for 2019 Comic-Con International. The annual cosplay celebration officially kicks off tomorrow, July 18, with a preview happening tonight. Here, Variety gives you a guide to this year's parties and activations. Make sure to check back for updates. Wednesday, July 17Amazon Prime [...]


This attractive woven willow basket is similar to the abandoned nests that Long-eared Owl and Hobby normally use.
There is a shortage of natural nesting sites, which is thought to be one of the major factors behind the decline of some of our once most-common birds, however less common species also face challenges when searching for appropriate breeding and roosting sites. Putting up a specialist nest box can encourage them to breed near your home.
For Long-eared Owls site in the lower half of a tree in woodland or a dense hedgerow near coarse grassland with tussocks; for Hobbies choose the top of a tree near the woodland edge overlooking farmland or a wetland.


The names of the three senior advisers who will sit on the Independent Reporting Mechanism (IRM) international expert panel were unveiled yesterday, and they certainly meet the high expectations of the international opengov community: Ireland's first female President and former UN High Commissioner for Refugees, Mary Robinson, Sudanese-born entrepreneur, Dr Mo Ibrahim, and Mozambican politician and wife of Nelson Mandela, Graça Machel.
The impressive calibre of my co-panellists Mary Robinson and Graca Machel underlines the integrity and autonomy of the IEP and I look forward to working with them.
Over the years, I have learned that good governance is essential to the fulfilment of human rights and to achieving sustainable development. Issues of governance can be measured, which is why I welcome the opportunity to serve as a member of the OGP's International Expert Panel.
These three high-profile senior advisers will soon be joined by five technical experts and together, during their two-year mandate, the eight will help ensure that the IRM delivers high quality, credible and independent reports each year on what OGP participating countries are doing to deliver on their commitments.
The appointment also comes at a time where ensuring the continued credibility and legitimacy of OGP is essential, and better internal governance is the necessary starting point for any credible international initiative. Robinson, Ibrahim and Machel will in this respect play a key role, as they will provide strategic advice in the initial development of the IRM's overall assessment approach and can use their global standing to raise the profile of the annual independent assessment reports for each participating country.
The United Kingdom was a founding member of the Partnership and it is a tribute to its growing importance as an international force for change that three such distinguished and experienced figures are joining this panel.
The announcement comes ahead of the OGP's Ministerial Level Steering Committee meeting in London on 4 December 2012. The Steering Committee meeting will hear updates on participating country action plans; and decide how the OGP can engage with other multilateral organisations, like the World Bank and the OECD, to share expertise and resource. This will be the first time that multilaterals have formally supported an international organisation of this kind.
Also on 4 December, the UK will fulfil a commitment under its own transparency action plan with the official opening of the Open Data Institute. The Institute's founders Sir Tim Berners-Lee – inventor of the worldwide web – and Professor Nigel Shadbolt have assembled an impressive team to help government and business identify commercially valuable public data, nurture innovative data-driven start-ups, and support both the public and private sectors so they can work effectively with open data.
We can certainly look forward to a very intense week of opengov debates in London and around the world following these important announcements. And, in true OGP spirit, we hope to have as many people involved in those discussions as possible!