Llallagua Formation | |
---|---|
Stratigraphic range: Rhuddanian-Homerian ~ | |
Type | Geological formation |
Underlies | Kirusillas Formation |
Lithology | |
Primary | Sandstone |
Other | Shale |
Location | |
Coordinates | 17°48′S64°48′W / 17.8°S 64.8°W |
Approximate paleocoordinates | 46°30′S127°54′W / 46.5°S 127.9°W |
Region | Potosí Department |
Country | Bolivia |
Extent | Cordillera Oriental |
Type section | |
Named for | Llallagua |
The Llallagua Formation is a Rhuddanian to Homerian geologic formation of western Bolivia. The formation comprises siliciclastic sediments. The fossil fauna suggests a warm water, nearshore current was active allowing northern hemisphere benthos to exist in the formation. [1]
The formation has provided the following fossils:
Enchodus is an extinct genus of aulopiform ray-finned fish related to lancetfish and lizardfish. Species of Enchodus flourished during the Late Cretaceous, and there is some evidence that they may have survived to the Paleocene or Eocene; however, this may just represent reworked Cretaceous material.
Pyrotheria is an order of extinct meridiungulate mammals. These elephant-like ungulates include the genera Baguatherium, Carolozittelia, Colombitherium, Griphodon, Propyrotherium, Proticia, and Pyrotherium.
Scelidotherium is an extinct genus of ground sloth of the family Scelidotheriidae, endemic to South America during the Late Pleistocene epoch. It lived from 780,000 to 11,000 years ago, existing for approximately 0.67 million years.
Hapalops is an extinct genus of ground sloth from the Early to Late Miocene of Brazil, Bolivia, Colombia, and Argentina in South America.
Rhynchippus is an extinct genus of notoungulate mammals from the Late Oligocene of South America. The genus was first described by Florentino Ameghino in 1897 and the type species is R. equinus, with lectotype MACN A 52–31. Fossils of Rhynchippus have been found in the Agua de la Piedra and Sarmiento Formations of Argentina, the Salla and Petaca Formations of Bolivia, the Tremembé Formation of Brazil, and the Moquegua Formation of Peru.
Zulmasuchus is an extinct genus of sebecid sebecosuchian mesoeucrocodylian. Its fossils have been found in Early Paleocene-age rocks of the Santa Lucía Formation in Bolivia. Zulmasuchus was named in 2007 by Alfredo Paolillo and Omar Linares for fossils originally described by Buffetaut and Marshall in 1991 as Sebecus querejazus. Thus, the type species is Sebecus querezajus and the combinatio nova is Zulmasuchus querejazus.
Xenastrapotherium is an extinct genus of astrapothere, a type of hoofed herbivorous mammal, native to South America, which lived in the Middle to Late Miocene period, typically during the Laventan stage. It is a member of the family Astrapotheriidae in the subfamily Uruguaytheriinae, large astrapotheres, equipped with a trunk-like nose and protruding teeth, similar to the elephants, but their tusks were the canine teeth, not the incisors. Xenastrapotherium was a genus widely distributed in northern South America, in contrast to other species of astrapotheres which lived in the area of the Southern Cone of the continent. It differed from other astrapotheres by having two lower incisors on each side of the jaw and the tusks have a pronounced longitudinal curvature, although their general shape and size are probably very similar to Astrapotherium, whose weight would be 900 to 1,500 kilograms, comparable to the current black rhinoceros.
The Wasatch Formation (Tw) is an extensive highly fossiliferous geologic formation stretching across several basins in Idaho, Montana, Wyoming, Utah and western Colorado. It preserves fossils dating back to the Early Eocene period. The formation defines the Wasatchian or Lostcabinian, a period of time used within the NALMA classification, but the formation ranges in age from the Clarkforkian to Bridgerian.
The Verulam Formation is a geologic formation and Lagerstätte in Ontario, Canada. It preserves fossils dating back to the Katian stage of the Ordovician period, or Shermanian to Chatfieldian in the regional stratigraphy.
The Iscayachi Formation, in older literature also referred to as Guanacuno Formation, is an extensive Tremadocian geologic formation of western and southern Bolivia. The shales and sandstones were deposited in a shallow marine to pro-delta environment. The formation reaches a thickness of 1,000 metres (3,300 ft).
The Pircancha Formation is a Floian to Dapingian geologic formation of southern Bolivia. The green mudstones, shales and sandstones were deposited in a shallow to open marine environment. The fossil Pircanchaspis rinconensis is named after the formation.
The Cancañiri Formation, also named as Cancañiri Tillite, is a Katian to Hirnantian geologic formation of central Bolivia. The pebbly, argillaceous sandstones, shales and siltstones of the up to 1,500 metres (4,900 ft) thick formation, were deposited in a glacial foreshore to deep water turbiditic environment. The formation is named after Cancañiri, a mining town close to Llallagua, where a local legend of a possessed woman is believed. The formation overlies the San Benito Formation in Cochabamba and the Amutara Formation in other parts. The Cancañiri Formation is overlain by the Uncía Formation.
The Kirusillas Formation is a Homerian geologic formation of central Bolivia. The formation comprises black shales, overlies the Llallagua Formation and is overlain by the Pampa and Guayabillas Formations. The Kirusillas Formation is laterally equivalent to the Lipeón Formation. The formation is a potential source rock for shale oil and shale gas.
The Gamoneda Formation is an Emsian geologic formation of southern Bolivia. The approximately 340 metres (1,120 ft) thick formation comprises marine micaceous grey siltstones and burrowed grey sandstones and shales.
The Lipeón Formation is a Telychian to Pridoli geologic formation of southern Bolivia and northwestern Argentina. The formation comprises sandstones and siltstones. Plant fossils comprising rhyniophytes are scattered throughout, with some abundant concentrations on micaceous bedding plains. The fossil flora is the oldest of South America. Also present were quite diverse small, irregularly branching fragments possibly the tips of algae such as Buthotrephis or Hungerfordia.
The Calvert Formation is a geologic formation in Maryland, Virginia, and Delaware. It preserves fossils dating back to the early to middle Miocene epoch of the Neogene period. It is one of the three formations which make up the Calvert Cliffs, all of which are part of the Chesapeake Group.
The Anzaldo Formation is a Katian geologic formation of central Bolivia. The formation belongs to the Cochabamba Group, overlies the Capinota Formation and is overlain by the San Benito Formation.
Ronwolffia is an extinct genus of horned armadillo (Peltephilidae), distantly related to the modern species of armadillos and to the extinct glyptodonts. It lived during the Oligocene in what is now the Salla Formation in Bolivia.
Brucemacfaddenia is an extinct genus of interatheriine notoungulates that lived during the Late Oligocene in what is now Bolivia. Fossils of this genus have been found in the Salla Formation of Bolivia.