Environmental Five samples from the seafloor in Lonsdale Bay, two from a beach and one from Limited samples but confirms likely Geosurveys Pty Ltd a cliffed dune along The Narrows origins and history of sand movement (1997) - Lonsdale Bay Various analytical methods used Analysis of Beach, Dune Conclusions and Offshore Sand Similarity of texture, composition and grain size characteristics point to a Analysis of sand samples to in common origin inform the Vantree (1998) Shape and texture consistent with an aeolian history derived from dunes – report but subject to wave transport and worked in shallow environment Carbonate/quartz consistent with other beach and dune surveys Broad similarities between onshore and offshore material suggests an exchange and reworking of material between the environments Sufficient differences to suggest episodes of different nourishment and transport occur Repeated sampling combined with profiling would reveal actual rate of exchange and mobility of sand bodies Lawson and Treloar Pty Extensive field measurements to support modelling and investigations as part of Provides information on broad Ltd (1998) - Lonsdale Vantree (1998) report. processes Bight Coastal Processes Aim to measure transformation of waves as they propagate from Bass Staright Limited time frame for measurement of Investigation Wave and into Lonsdale Bight and to determine the strength and spatial distribution of waves but suitable to assess Current Measurements currents within Lonsdale Bight and the entrance region. transormations Data included waves and currents for 2 months at a number of sites including 2 No apparent data near Point Lonsdale This report details the wave in Lonsdale Bay. Front Beach and current measurements carried out to inform the Spatial variations in currents were measured via ADCP transects over 3 days but modelling and assessment of the quality was compromised by adverse conditions. coastal processes undertaken Waves for the Vantree (1998) report. Marked reduction in wave height between Bass Straight and the beaches of Lonsdale Wave heights are modified by strong currents Wave periods indicate swell from the Southern Ocean and from a steady direction Currents Flood tide currents in Lonsdale Bight approx. parallel to the coast and stronger than ebb near the beach
Environmental Geosurveys Pty Ltd (1997) - Lonsdale Bay Analysis of Beach, Dune and Offshore Sand Analysis of sand samples to in inform the Vantree (1998) report Five samples from the seafloor in Lonsdale Bay, two from a beach and one from a cliffed dune along The Narrows Various analytical methods used Conclusions Similarity of texture, composition and grain size characteristics point to a common origin Shape and texture consistent with an aeolian history – derived from dunes but subject to wave transport and worked in shallow environment Carbonate/quartz consistent with other beach and dune surveys Broad similarities between onshore and offshore material suggests an exchange and reworking of material between the environments Sufficient differences to suggest episodes of different nourishment and transport occur Repeated sampling combined with profiling would reveal actual rate of exchange and mobility of sand bodies Limited samples but confirms likely origins and history of sand movement Lawson and Treloar Pty Ltd (1998) - Lonsdale Bight Coastal Processes Investigation Wave and Current Measurements This report details the wave and current measurements carried out to inform the modelling and assessment of coastal processes undertaken for the Vantree (1998) report. Extensive field measurements to support modelling and investigations as part of Vantree (1998) report. Aim to measure transformation of waves as they propagate from Bass Staright into Lonsdale Bight and to determine the strength and spatial distribution of currents within Lonsdale Bight and the entrance region. Data included waves and currents for 2 months at a number of sites including 2 in Lonsdale Bay. Spatial variations in currents were measured via ADCP transects over 3 days but the quality was compromised by adverse conditions. Waves Marked reduction in wave height between Bass Straight and the beaches of Lonsdale Wave heights are modified by strong currents Wave periods indicate swell from the Southern Ocean and from a steady direction Currents Flood tide currents in Lonsdale Bight approx. parallel to the coast and stronger than ebb near the beach Provides information on broad processes Limited time frame for measurement of waves but suitable to assess transormations No apparent data near Point Lonsdale Front Beach
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