The Umm Irna Formation is a geological formation in

Jordan Jordan ( ar, الأردن; tr. ' ), officially the Hashemite Kingdom of Jordan,; tr. ' is a country in Western Asia. It is situated at the crossroads of Asia, Africa, and Europe, within the Levant region, on the East Bank of the Jordan Rive ...

. It is found in several outcrops in Jordan in the area around the eastern shore of the Dead Sea. It is

Late Permian Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, ...

(likely

Changhsingian In the geologic time scale, the Changhsingian or Changxingian is the latest age or uppermost stage of the Permian. It is also the upper or latest of two subdivisions of the Lopingian Epoch or Series. The Changhsingian lasted from to 251.902 ...

) in age, and is the oldest unit in the succession, overlying the Cambrian aged Umm Ishrin Sandstone Formation. The formation predominantly consists of

sandstones 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) b ...

claystones Mudrocks are a class of fine-grained siliciclastic sedimentary rocks. The varying types of mudrocks include siltstone, claystone, mudstone, slate, and shale. Most of the particles of which the stone is composed are less than and are too smal ...

and

mudstones 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.'' ...

deposited in fluvial and

lacustrine A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much larger ...

conditions. The formation is of considerable paleobotanical interest, as it preserves the earliest known remains of plant groups that would become widespread during the Mesozoic, including Corystosperm seed ferns, represented by the widespread Triassic genus ''

Dicroidium ''Dicroidium'' is an extinct genus of fork-leaved seed ferns that were widely distributed over Gondwana during the Triassic (). Their fossils are known from South Africa, the Arabian Peninsula, Australia, New Zealand, South America, Madagascar ...

,''

cycads Cycads are seed plants that typically have a stout and woody ( ligneous) trunk with a crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants of a species are either male o ...

(''cf. Ctenis''),

podocarp Podocarpaceae is a large family of mainly Southern Hemisphere conifers, known in English as podocarps, comprising about 156 species of evergreen trees and shrubs.James E. Eckenwalder. 2009. ''Conifers of the World''. Portland, Oregon: Timber Pr ...

conifers, as well as

Bennettitales Bennettitales (also known as cycadeoids) is an extinct order of seed plants that first appeared in the Permian period and became extinct in most areas toward the end of the Cretaceous. Bennettitales are among the most common Mesozoic seed plants ...

. Other plant groups present in the formation include

Noeggerathiales Noeggerathiales is a now- extinct order of vascular plants. The fossil range of the order extends from the Upper Carboniferous to the upper Permian (Lopingian). Due to gaps in the fossil record, the group is incompletely known and poorly defined, ...

, gigantopterids, lyginopterids and possible ginkgophytes.

References

{{reflist Geologic formations of Jordan Permian System of Asia Lopingian geology Shale formations Siltstone formations Sandstone formations Paleontology in Jordan