The Lost Burro Formation is a

Middle Middle or The Middle may refer to: * Centre (geometry), the point equally distant from the outer limits. Places * Middle (sheading), a subdivision of the Isle of Man * Middle Bay (disambiguation) * Middle Brook (disambiguation) * Middle Creek ...

to Upper/Late

Devonian The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian per ...

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

in the

Mojave Desert The Mojave Desert (; ; ) is a desert in the rain shadow of the southern Sierra Nevada mountains and Transverse Ranges in the Southwestern United States. Named for the Indigenous peoples of the Americas, indigenous Mohave people, it is located pr ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

in the

Western United States The Western United States (also called the American West, the Western States, the Far West, the Western territories, and the West) is List of regions of the United States, census regions United States Census Bureau. As American settlement i ...

Geology

The Dolomite formation is exposed in sections of the

Darwin Hills The Darwin Hills are a mountain range in Inyo County, California, situated near the Argus Range, Panamint Range, and Inyo Mountains. Darwin Falls and the Darwin Falls Wilderness are located in the Darwin Hills. They were named after Dr. Darwi ...

, the Santa Rosa Hills, the Talc City Hills, the

Inyo Mountains The Inyo Mountains are a short mountain range east of the Sierra Nevada in eastern California in the United States. The range separates the Owens Valley to the west from Saline Valley to the east, extending for approximately south-southeast f ...

near the

Cerro Gordo Mines The Cerro Gordo Mines are a collection of abandoned mines located in Cerro Gordo in the Inyo Mountains, Inyo County, near Lone Pine, California. Mining operations spanned 1866 to 1957, producing high grade silver, lead, and zinc ore; and, mo ...

, the Panamint Range near Towne Pass, and the

Argus Range The Argus Range is a mountain range located primarily in Inyo County, California, southeast of the town of Darwin. The range forms the western boundary of Panamint Valley, and the northwestern boundary of Searles Valley. The Coso Range is loc ...

Fossils

Outcrops of the formation in

Death Valley National Park Death Valley National Park is a national park of the United States that straddles the California–Nevada border, east of the Sierra Nevada. The park boundaries include Death Valley, the northern section of Panamint Valley, the southern sect ...

have produced fossils of the

placoderm Placoderms (from Ancient Greek πλάξ 'plax'', ''plakos'''Plate (animal anatomy), plate' and δέρμα 'derma'''skin') are vertebrate animals of the class (biology), class Placodermi, an extinct group of prehistoric fish known from Pal ...

Dunkleosteus terrelli ''Dunkleosteus'' is an extinct genus of large arthrodira, arthrodire ("jointed-neck") fish that existed during the Late Devonian period, about 382–358 million years ago. It was a pelagic fish inhabiting open waters, and one of the first verteb ...

'', a small

cladodont This is a typical Cladodont tooth, of a Glikmanius.html" ;"title="shark called ''Glikmanius">shark called ''Glikmanius'' Cladodont (from Latin cladus, meaning branch and Greek Odon, meaning tooth) is the term for a common category of early Devoni ...

shark Sharks are a group of elasmobranch cartilaginous fish characterized by a ribless endoskeleton, dermal denticles, five to seven gill slits on each side, and pectoral fins that are not fused to the head. Modern sharks are classified within the ...

, the crushing tooth of a cochliodont, and the pteraspidid '' Blieckaspis priscillae''."Death Valley National Park," Hunt, Santucci, and Kenworthy (2006); page 63.Hunt, ReBecca K., Vincent L. Santucci and Jason Kenworthy. 2006. "A preliminary inventory of fossil fish from National Park Service units." in S.G. Lucas, J.A. Spielmann, P.M. Hester, J.P. Kenworthy, and V.L. Santucci (ed.s), Fossils from Federal Lands. New Mexico Museum of Natural History and Science Bulletin 34, pp. 63–69.

References

Devonian California Dolomite formations of the United States Upper Devonian Series Middle Devonian Series Death Valley National Park Geology of Inyo County, California Natural history of the Mojave Desert Inyo Mountains Panamint Range Devonian System of North America Geologic formations of California {{California-geologic-formation-stub