The Patagonian Niolamia belongs to the Sarmienti Formation.[22] Fossils of the mid-Cretaceous Argentinosaurus, which may be the largest of all dinosaurs, have been found in Patagonia, and a model of the mid-Jurassic Piatnitzkysaurus graces the concourse of the Trelew airport (the skeleton is in the Trelew paleontological museum; the museum's staff has also announced the discovery of a species of dinosaur even bigger than Argentinosaurus[23]). Of more than paleontological interest,[24] the middle Jurassic Los Molles Formation and the still richer late Jurassic (Tithonian) and early Cretaceous (Berriasian) Vaca Muerta formation above it in the Neuquén basin are reported to contain huge hydrocarbon reserves (mostly gas in Los Molles, both gas and oil in Vaca Muerta) partly accessible through hydraulic fracturing.[25] Other specimens of the interesting fauna of Patagonia, belonging to the Middle Cenozoic, are the gigantic wingless birds, exceeding in size any hitherto known, and the singular mammal Pyrotherium, also of very large dimensions.