The Jialingjiang Formation (嘉陵江组) is a geologic feature associated with the

Sichuan Basin The Sichuan Basin (), formerly transliterated as the Szechwan Basin, sometimes called the Red Basin, is a lowland region in southwestern China. It is surrounded by mountains on all sides and is drained by the upper Yangtze River and its tributar ...

of China, generally underlying the area of the basin, with its origins dating to the

Early Triassic The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between 251.9 Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which ...

period of geologic time, around a quarter of a billion years ago, and before. The Jialingjiang Formation is a geologic group feature upon the

Yangtze Plate The Yangtze plate, also called the South China block or the South China subplate, comprises the bulk of southern China. It is separated on the east from the Okinawa plate by a rift that forms the Okinawa Trough which is a back-arc basin, on the ...

, which is a

tectonic Tectonics ( via Latin ) are the processes that result in the structure and properties of the Earth's crust and its evolution through time. The field of ''planetary tectonics'' extends the concept to other planets and moons. These processes ...

feature of the

Earth's crust Earth's crust is its thick outer shell of rock, referring to less than one percent of the planet's radius and volume. It is the top component of the lithosphere, a solidified division of Earth's layers that includes the crust and the upper ...

. The Jialingjiang Formation is important to paleontologists or other people interested in ancient life forms due to the fossil evidence incorporated therein (such as for

Eretmorhipis ''Eretmorhipis'' (meaning "oar fan" from the Greek '' '', "oar", and '' '', "fan") is an extinct genus of hupehsuchian marine reptiles from the Early Triassic of China. It is currently known from two specimens that were discovered in an exposure ...

and other

Ichthyosaur Ichthyosauria is an order of large extinct marine reptiles sometimes referred to as "ichthyosaurs", although the term is also used for wider clades in which the order resides. Ichthyosaurians thrived during much of the Mesozoic era; based on fo ...

relatives). Also, scientific study of this formation group provides insight into Late Triassic

tectonic inversion In structural geology, inversion or basin inversion relates to the relative uplift of a sedimentary basin or as a result of crust (geology), crustal shortening. This normally excludes uplift developed in the fault (geology), footwalls of later ...

based on analysis of detrital zircon U–Pb chronology (involving the element

uranium Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Ura ...

converting to

lead Lead () is a chemical element; it has Chemical symbol, symbol Pb (from Latin ) and atomic number 82. It is a Heavy metal (elements), heavy metal that is density, denser than most common materials. Lead is Mohs scale, soft and Ductility, malleabl ...

over time due to

radioactive decay Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is conside ...

). The Jialingjiang Formation is also of interest in history as it has been a source for humans to extract valuable economic goods such as salt and natural gas for many centuries.

Hydrocarbon resources

The history of the Jialingjiang Formation explains the origins of the hydrocarbon resources which have historically or in the future may be extracted. The primary hydrocarbon resource of the Sichuan Basin is

natural gas Natural gas (also fossil gas, methane gas, and gas) is a naturally occurring compound of gaseous hydrocarbons, primarily methane (95%), small amounts of higher alkanes, and traces of carbon dioxide and nitrogen, hydrogen sulfide and helium ...

References

{{reflist Geologic formations of China Triassic System of Asia Triassic China

Hydrocarbon resources

See also

References