The Zhiluo Formation is a

geological 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 China, it is also alternatively considered a

geological group In geology, a group is a lithostratigraphic unit consisting of a series of related formations that have been classified together to form a group. Formations are the fundamental unit of stratigraphy. Groups may sometimes be combined into superg ...

under the name Zhiluo Group (formerly known as the Chiloo Group). It dates to the

Middle Jurassic The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from about 174.1 to 163.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relatively rare, but geological formations co ...

. It consists of

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

mudstone Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from '' shale'' by its lack of fissility (parallel layering).Blatt, H., and R.J. Tracy, 1996, ''Petrology. ...

and

siltstone Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.Blatt ''et al.'' 1980, p ...

of varying colours. It has received scientific attention for its uranium ore bodies present in the lower part of the formation. Fossil theropod tracks have been reported from the formation.Weishampel, et al. (2004). "Dinosaur distribution." Pp. 517-607. These were described from two footprints found in Jiaoping Coal Mine by C. C. Young in 1966 as '' Shensipus tungchuanensis.'' These were in 2015 suggested to belong to ''

Anomoepus ''Anomoepus'' is the name assigned to several fossil footprints first reported from Early Jurassic beds of the Connecticut River Valley, Massachusetts, USA in 1802. All four feet have left impressions. The smaller forefeet have five toes, wher ...

.'' The dinosaur ''

Lingwulong ''Lingwulong'' is a genus of dicraeosaurid sauropod dinosaur from the Middle Jurassic of what is now Lingwu, Yinchuan, Ningxia, China. The type and only species is ''L. shenqi'', known from several partial skeletons. It is the earliest-aged neo ...

'' has been suggested to have come from the strata of this formation, previously having been attributed to the underlying

Yanan Formation The Yanan Formation, alternatively spelled the Yan'an Formation (), is a geological formation in China, it is also alternatively considered a Group (stratigraphy), group. The age of the formation is uncertain, with estimates ranging from Toarcian ...

Footnotes

References

* Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. 861 pp. . Geologic groups of Asia Geologic formations of China {{China-geologic-formation-stub Jurassic System of Asia

See also

Footnotes

References