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 (d ...

to Upper/Late

Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, w ...

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 ( ; mov, Hayikwiir Mat'aar; es, Desierto de Mojave) is a desert in the rain shadow of the Sierra Nevada mountains in the Southwestern United States. It is named for the indigenous Mojave people. It is located primarily i ...

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the ...

in the

Western United States The Western United States (also called the American West, the Far West, and the West) is the region comprising the westernmost states of the United States. As American settlement in the U.S. expanded westward, the meaning of the term ''the Wes ...

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. Darwin ...

, 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 from ...

near the Cerro Gordo Mines, the Panamint Range near Towne Pass, and the

Argus Range The Argus Range is a mountain range located 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 located to the we ...

Fossils

Outcrops of the formation in

Death Valley National Park Death Valley National Park is an American national park 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 section of Eure ...

have produced fossils of the placoderm ''

Dunkleosteus terrelli ''Dunkleosteus'' is an extinct genus of large armored, jawed fishes that existed during the Late Devonian period, about 382–358 million years ago. It consists of ten species, some of which are among the largest placoderms to have ever lived ...

'', 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 Devonia ...

shark Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachi ...

, the crushing tooth of a cochliodont, and the

pteraspidid Pteraspididae is an extinct family of heterostracan vertebrates. It is an Early Devonian-aged family that contains the stereotypical, torpedo-shaped pteraspidids, such as the type genus, ''Pteraspis'', and its close relatives ''Errivaspis'' a ...

'' 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 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