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Pisco Formation

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The Pisco Formation is a geologic formation located in Peru , on the southern coastal desert of Ica and Arequipa . The approximately 640 metres (2,100 ft) thick formation was deposited in the Pisco Basin , spanning an age from the Late Miocene up to the Early Pliocene , roughly from 9.6 to 4.5 Ma. The tuffaceous sandstones , diatomaceous siltstones , conglomerates and dolomites were deposited in a lagoonal to near-shore environment , in bays similar to other Pacific South American formations as the Bahía Inglesa and Coquimbo Formations of Chile.

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20-479: Several specialists consider the Pisco Formation one of the most important Lagerstätten , based on the large amount of exceptionally preserved marine fossils, including sharks (most notably megalodon ), penguins, whales, dolphins, birds, marine crocodiles and aquatic giant sloths . Famous fossils found in these layers include the giant raptorial sperm whale Livyatan , the aquatic sloth Thalassocnus ,

40-754: A Konservat-Lagerstätte may be based on a number of different factors which constitute "exceptional preservation". These may include the completeness of specimens, soft tissue preservation, fine-scale detail, taxonomic richness, distinctive taphonomic pathways (often multiple at the same site), the extent of the fossil layer in time and space, and particular sediment facies encouraging preservation. The world's major Lagerstätten include: Lakhanda Lagerstätte 1030-1000 Ma Uchur-Maya Depression, Russia Bitter Springs 1000–850 Ma South Australia Preserved fossils include cyanobacteria microfossils . Chichkan Lagerstätte 775 Ma Kazakhstan Doushantuo Formation 600–555 Ma Guizhou Province, China Spans

60-471: A death mask . It is a part of the larger Buen Formation , and has a fauna similar to the Maotianshan shales. Sinsk Algal Lens 518 Ma Yakutia , Russia One of the oldest known Cambrian lagerstätten . The fauna of this site is unique, as it seems that they were adapted to living in dysaerobic conditions. Santana Formation The Santana Group is a geologic group, formerly included as

80-444: A fluviolacustrine phase and is composed of red and gray shales, siltstones and claystones. The Santana Group was formed during this stage and comprises three stratigraphic units: 5) Post-rift II phase - Albian to Cenomanian - characterized by a major sag phase, and is formed by two stratigraphic units: The upper and lower formations of the group are highly fossiliferous, with mainly insects, amphibians, fish, and flora dominating

100-1017: The Devonian Hunsrück Slates and Gogo Formation , the Carboniferous Mazon Creek , the Triassic Madygen Formation , the Jurassic Posidonia Shale and Solnhofen Limestone , the Cretaceous Yixian , Santana , & Agua Nueva formations and the Tanis Fossil Site , the Eocene Fur Formation , Green River Formation , Messel Formation & Monte Bolca , the Miocene Foulden Maar and Ashfall Fossil Beds ,

120-756: The Missão Velha Formation , constituted by medium to coarse-grained quartz-feldspathic sandstones, locally conglomeratic, that contains entire trunks and fragments of silicified wood ( Dadoxilon benderi ) conifer 3) Rift phase - Berriasian to Hauterivian - characterized by increasing mechanical subsidence that created a system of grabens and half grabens. It is represented by the Abaiara Formation , that includes shales, siltstones , sandstones and conglomerates 4) Post-Rift I phase - Aptian to Albian - characterized by thermal subsidence. The lowermost unit Barbalha Formation , represents

140-601: The Pliocene Gray Fossil Site , and the Pleistocene Naracoorte Caves & La Brea Tar Pits . Palaeontologists distinguish two kinds: Konservat-Lagerstätten preserve lightly sclerotized and soft-bodied organisms or traces of organisms that are not otherwise preserved in the usual shelly and bony fossil record; thus, they offer more complete records of ancient biodiversity and behavior and enable some reconstruction of

160-608: The palaeoecology of ancient aquatic communities. In 1986, Simon Conway Morris calculated only about 14% of genera in the Burgess Shale had possessed biomineralized tissues in life. The affinities of the shelly elements of conodonts were mysterious until the associated soft tissues were discovered near Edinburgh, Scotland, in the Granton Lower Oil Shale of the Carboniferous . Information from

180-655: The Borborema Province. It is represented by the deposits of the Cariri Formation , that include medium to coarse-grained quartz sandstones , locally conglomeratic , deposited in large braided fluvial systems 2) Pre-rift phase - Tithonian - characterized by the mechanical subsidence due to lithosphere thinning that preceded the rift. It is represented by the Brejo Santo Formation , that comprises red shales and claystones , and

200-465: The Maotianshan shale the world's most important for understanding the evolution of early multi-cellular life. Qingjiang biota 518 Ma Hubei , China This site is particularly notable due to both the large proportion of new taxa represented (approximately 53% of the specimens), and the notable volume of soft-body tissue preservation. Sirius Passet 523-518 Ma Greenland A site known for its fauna, and that they were most likely preserved by

220-467: The broader range of organisms found in Lagerstätten have contributed to recent phylogenetic reconstructions of some major metazoan groups. Lagerstätten seem to be temporally autocorrelated, perhaps because global environmental factors such as climate might affect their deposition. A number of taphonomic pathways may produce Konservat-Lagerstätten : The identification of a fossil site as

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240-705: The decomposition of both gross and fine biological features until long after a durable impression was created in the surrounding matrix. Fossil-Lagerstätten span geological time from the Neoproterozoic era to the present . Worldwide, some of the best examples of near-perfect fossilization are the Cambrian Maotianshan shales and Burgess Shale , the Ordovician Soom Shale , the Silurian Waukesha Biota ,

260-778: The formation have been dated at 2 Ma, corresponding to the Early Pleistocene ( Uquian ). Fossils of the Humboldt penguin were found in these deposits at the Yauca locality. Lagerst%C3%A4tte A Fossil-Lagerstätte ( German: [ˈlaːɡɐˌʃtɛtə] , from Lager 'storage, lair' Stätte 'place'; plural Lagerstätten ) is a sedimentary deposit that exhibits extraordinary fossils with exceptional preservation—sometimes including preserved soft tissues. These formations may have resulted from carcass burial in an anoxic environment with minimal bacteria, thus delaying

280-467: The formation is estimated at 640 metres (2,100 ft). The formation unconformably overlies the Chilcatay and Caballas Formations . The Pisco Formation has provided a rich resource of marine fauna, including marine mammals like cetaceans and seals, large fishes, reptiles, and penguins. It is also one of the richest sites in the world for fossil cetaceans , with close to 500 examples being found in

300-543: The formation. The oldest fossils of the aquatic sloth Thalassocnus ( T. antiquus ) come from the Aguada de Lomas horizon of the Pisco Formation and were dated at roughly 7 Ma. The youngest specimen ( T. carolomartini ) was found in the Sacaco horizon and dated to approximately 3 Ma. Thalassocnus was preyed upon by the probable apex predators of the environment, Livyatan and megalodon . The youngest strata belonging to

320-580: The group contained several feathers of birds, among those the first record of Mesozoic birds in Brazil. The Romualdo and Crato Formations are renowned for their excellent conservation and designated Lagerstätten . In 2006, the Araripe Basin was designated a UNESCO Global Geopark . The Santana Group was formerly described as belonging to the Araripe Group. The fossiliferous Santana Formation

340-865: The middle part of the Araripe Group, in the Araripe Basin of northeastern Brazil . The group comprises the Crato , Ipubi and Romualdo Formations and is dated to the Aptian to Albian stages of the Early Cretaceous . The formations of the group were deposited in a lacustrine to subtidal shallow marine environment in the Araripe rift basin . The Santana Group has provided a rich assemblage of fossils; flora, fish, arthropods insects, turtles, snakes, dinosaurs including Irritator , and pterosaurs such as Thalassodromeus . The stratigraphic units of

360-797: The poorly understood interval between the end of the Cryogenian period and the late Ediacaran Avalon explosion . Mistaken Point 565 Ma Newfoundland, Canada This site contains one of the most diverse and well-preserved collections of Precambrian fossils . Ediacara Hills 555 Ma South Australia The type location the Ediacaran period, and has preserved a significant amount of fossils from that time. Khatyspyt Lagerstätte 544 Ma Yakutia , Russia A Late Ediacaran lagerstätte preserving an Avalon-type biota. Maotianshan Shales (Chengjiang) 518 Ma Yunnan , China The preservation of an extremely diverse faunal assemblage renders

380-667: The sperm whale Acrophyseter , and the walrus-like dolphin Odobenocetops . The Pisco Formation of the Pisco Basin consists of tuffaceous sandstones , diatomaceous yellow to gray siltstones and a basal conglomerate . The formation is deposited from Pisco in the north to Yauca in the south. The northern portion is known as the Ocucaje Area and the southern part as the Sacaco Area. The total thickness of

400-741: Was previously defined as containing the Crato and Romualdo Members, but redefinition of the stratigraphy led to the establishment of the Santana Group, replacing the middle part of the Araripe Group and the former Crato, Ipubi and Romualdo members were elevated to separate formations. The tectono-sedimentary evolution of the Araripe Basin, located in the Borborema Geologic Province, encompasses four stages, with five tectonostratigraphic phases: 1) Syneclise phase - Silurian to Devonian - characterized by tectonic quiescence in

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