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Umm Irna Formation
The Umm Irna Formation is a geological formation in Jordan. It is found in several outcrops in Jordan in the area around the eastern shore of the Dead Sea. It is Late Permian (likely Changhsingian) in age, and is the oldest unit in the succession, overlying the Cambrian aged Umm Ishrin Sandstone Formation. The formation predominantly consists of sandstones, claystones and mudstones deposited in fluvial and lacustrine 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,'' cycads (''cf. Ctenis''), podocarp conifers, as well as Bennettitales. 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 (Lopin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Claystone
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 small to study readily in the field. At first sight, the rock types appear quite similar; however, there are important differences in composition and nomenclature. There has been a great deal of disagreement involving the classification of mudrocks. A few important hurdles to their classification include the following: # Mudrocks are the least understood and among the most understudied sedimentary rocks to date. # Studying mudrock constituents is difficult due to their diminutive size and susceptibility to weathering on outcrops. # And most importantly, scientists accept more than one classification scheme. Mudrocks make up 50% of the sedimentary rocks in the geologic record and are easily the most widespread deposits on Earth. Fine sedimen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lacustrine Deposits
Lacustrine deposits are sedimentary rock formations which formed in the bottom of ancient lakes. A common characteristic of lacustrine deposits is that a river or stream channel has carried sediment into the basin. Lacustrine deposits form in all lake types including rift graben lakes, oxbow lakes, glacial lakes, and crater lakes. Lacustrine environments, like seas, are large bodies of water. They share similar sedimentary deposits which are mainly composed of low-energy particle sizes. Lacustrine deposits are typically very well sorted with highly laminated beds of silts, clays, and occasionally carbonates. In regards to geologic time, lakes are temporary and once they no longer receive water, they dry up and leave a formation. Lake types Lacustrine deposits can form in every variety of basins found in nature. How each basin originates is where the distinction between lacustrine deposit types stem. Rift graben lakes are formed from crustal stretching also known as rifting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permian System Of Asia
The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the region of Perm in Russia. The Permian witnessed the diversification of the two groups of amniotes, the synapsids and the sauropsids (reptiles). The world at the time was dominated by the supercontinent Pangaea, which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior. Amniotes, which could better cope with these drier conditions, rose to dominance in place of their amphibia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologic Formations Of Jordan
Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology, and so is treated as one major aspect of integrated Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface, and the processes that have shaped that structure. It also provides tools to determine the relative and absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Earth's past climates. Geologists broadly study the properties and processes of Ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ginkgophyte
Ginkgoales are a gymnosperm order containing only one extant species: ''Ginkgo biloba'', the ginkgo tree. It is monotypic, (the only taxon) within the class Ginkgoopsida, which itself is monotypic within the division Ginkgophyta . The order includes five families, of which only Ginkgoaceae remains extant. History Ginkgophyta and Cycadophyta have a very ancient divergence dating to the early Carboniferous. The earliest representative of the group in the fossil record is probably '' Trichopitys'' from the Asselian (299-293 million years ago) of France. The earliest representatives of ''Ginkgo'', represented by reproductive organs similar to the living species, first appear in the Middle Jurassic, alongside other, related forms such as ''Yimaia'' and ''Karkenia'', which have differently arranged reproductive structures and seeds associated with ''Ginkgo''-like leaves. The diversity of Ginkgoales declined during the Late Cretaceous and Cenozoic, coincident with the rise of flower ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyginopteridales
The Lyginopteridales were the archetypal pteridosperms: They were the first plant fossils to be described as pteridosperms and, thus, the group on which the concept of pteridosperms was first developed;Oliver, F. W. & Scott, D. H. (1904). "On the structure of the Palaeozoic seed ''Lagenostoma Lomaxi'', with a statement of the evidence upon which it is referred to ''Lyginodendron''." ''Philosophical Transactions of the Royal Society of London, Series B,'' 197: 193-247. they are the stratigraphically oldest-known pteridosperms, occurring first in late Devonian strata;Rothwell, G. W., Scheckler, S. E. & Gillespie, W. H. (1989). "''Elkinsia'' gen. nov., a Late Devonian gymnosperm with cupulate ovules." ''Botanical Gazette,'' 150: 170-189. and they have the most primitive features, most notably in the structure of their ovules.Long, A. G. (1959). "On the structure of ''Calymmatotheca kidstoni'' Calder (emended) and ''Genomosperma latens'' gen. et sp. nov. from the Calciferous Sand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gigantopterid
Gigantopterids (Gigantopteridales) is an extinct, possibly polyphyletic group of plants known from the Permian period. Gigantopterids were among the most advanced land plants of the Paleozoic Era and disappeared around the Permian–Triassic extinction event around 252 million years ago. Though some lineages of these plants managed to persist initially, they either disappeared entirely or adapted radically, evolving into undetermined descendants, as surviving life prospered again in much-altered ecosystems. One hypothesis proposes that at least some "gigantopterids" became the ancestors of angiosperms and/or Bennettitales and/or Caytoniales.Miller (2007) Gigantopterid fossils were documented as early as 1883, but only investigated more thoroughly in the early 20th century. Some of their most significant evidence was initially found in Texas, but they might have been present worldwide. Another key region for gigantopterid fossils is in China, and the consolidation of all major c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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, and their taxonomic status and position in the plant kingdom are uncertain. The Noeggerathiales have been proposed in the evolutionary scheme in two remotely related groups of vascular plants, the Pteropsida and the Sphenopsida. Noeggerathiales have been previously linked to horsetails and ferns, but are currently believed to be progymnosperms. Noeggerathiales had a tree fern The tree ferns are arborescent (tree-like) ferns that grow with a trunk elevating the fronds above ground level, making them trees. Many extant tree ferns are members of the order Cyatheales, to which belong the families Cyatheaceae (scaly tree ... like appearance, with leaves sprouting from the top of an unbranched trunk. They were primarily confined to the we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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, and had morphologies including shrub and cycad-like forms. The foliage of bennettitaleans is superficially nearly indistinguishable from that of cycads, but they are distinguished from cycads by their more complex flower-like reproductive organs, at least some of which were likely pollinated by insects. Although certainly gymnosperms (cone-bearing seed plants), the relationships of bennettitaleans to other seed plants is debated. Their general resemblance to cycads is contradicted by numerous more subtle features of their reproductive systems and leaf structure. Some authors have linked bennettitaleans to angiosperms (flowering plants) and gnetophytes (a rare and unusual group of modern gymnosperms), forming a broader group known as Anth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Podocarpaceae
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 Press. . It contains 19 genera if ''Phyllocladus'' is included and ''Manoao'' and ''Sundacarpus'' are recognized. The family is a classic member of the Antarctic flora, with its main centres of diversity in Australasia, particularly New Caledonia, Tasmania, and New Zealand, and to a slightly lesser extent Malesia and South America (primarily in the Andes Mountains). Several genera extend north of the equator into Indochina and the Philippines. ''Podocarpus'' reaches as far north as southern Japan and southern China in Asia, and Mexico in the Americas, and ''Nageia'' into southern China and southern India. Two genera also occur in sub-Saharan Africa, the widespread ''Podocarpus'' and the endemic '' Afrocarpus''. ''Parasitaxus usta'' is uniqu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ctenis
''Ctenis'' is a genus of fossil foliage attributable to the Cycadales, being one of the most common genera of cycad fossil leaves in the Mesozoic. Taxonomy The genus was first erected by Lindley and Hutton in "The fossil flora of Great Britain", based on material of ''Ctenis falcata'' from the Jurassic of Yorkshire. This species was later synonimized with ''Cycadites sulcicaulis,'' leading to the new combination ''Ctenis sulcicaulis'.'' Later, Seward, Florin, and Harris added details of the cuticle to the diagnosis of the genus. Description The leaves of ''Ctenis'' are once pinnate, and the pinnae have multiple parallel veins that often anastomosize (i.e. fuse together). The cuticle of ''Ctenis'' has stomata with guard cells arranged in a random fashion, and the stomatal apparatus has often a cuticular ring surrounding the stomatal pit. The cuticular surface is usually striate. Distribution Though ''Ctenis''-like leaves are known from the Late Permian Umm Irna Formation of Jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycad
Cycads are seed plants that typically have a stout and woody (ligneous) trunk (botany), trunk with a crown (botany), crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants of a species are either male or female. Cycads vary in size from having trunks only a few centimeters to several meters tall. They typically grow very slowly and live very long. Because of their superficial resemblance, they are sometimes mistaken for Arecaceae, palms or ferns, but they are not closely related to either group. Cycads are gymnosperms (naked-seeded), meaning their fertilization, unfertilized seeds are open to the air to be directly fertilized by pollination, as contrasted with angiosperms, which have enclosed seeds with more complex fertilization arrangements. Cycads have very specialized pollinators, usually a specific species of beetle. Both male and female cycads bear cones (strobilus, strobili), somewhat similar to conife ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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