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Lias Group
The Lias Group or Lias is a lithostratigraphic unit (a sequence of rock strata) found in a large area of western Europe, including the British Isles, the North Sea, the Low Countries and the north of Germany. It consists of marine limestones, shales, marls and clays. ''Lias'' is a Middle English term for hard limestone, used in this specific sense by geologists since 1833. In the past, geologists used ''Lias'' not only for the sequence of rock layers, but also for the timespan during which they were formed. It was thus an alternative name for the Early Jurassic epoch of the geologic timescale. It is now more specifically known that the Lias is Rhaetian to Toarcian in age (over a period of 20 million years between ) and thus also includes a part of the Triassic. The use of the name "Lias" for a unit of time is therefore slowly disappearing. Subdivisions In southern England, the Lias Group is often divided into Lower, Middle and Upper subgroups. In Southern England the Lias is di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithostratigraphy
Lithostratigraphy is a sub-discipline of stratigraphy, the geological science associated with the study of strata or rock layers. Major focuses include geochronology, comparative geology, and petrology. In general, strata are primarily igneous or sedimentary relating to how the rock was formed. Sedimentary layers are laid down by deposition of sediment associated with weathering processes, decaying organic matter (biogenic) or through chemical precipitation. These layers are often distinguishable as having many fossils and are important for the study of biostratigraphy. Igneous layers occur as stacks of lava flows, layers of lava fragments (called tephra) both erupted onto the Earth's surface by volcanoes, and in layered intrusions formed deep underground. Igneous layers are generally devoid of fossils and represent magmatic or volcanic activity that occurred during the geologic history of an area. There are a number of principles that are used to explain the appearance of stra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
England
England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe by the North Sea to the east and the English Channel to the south. The country covers five-eighths of the island of Great Britain, which lies in the North Atlantic, and includes over 100 smaller islands, such as the Isles of Scilly and the Isle of Wight. The area now called England was first inhabited by modern humans during the Upper Paleolithic period, but takes its name from the Angles, a Germanic tribe deriving its name from the Anglia peninsula, who settled during the 5th and 6th centuries. England became a unified state in the 10th century and has had a significant cultural and legal impact on the wider world since the Age of Discovery, which began during the 15th century. The English language, the Anglican Church, and Engli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redcar Mudstone Formation
The Redcar Mudstone Formation is a geological formation in North Yorkshire, England. Part of the Lias Group, it was deposited in the Hettangian to Pliensbachian stages of the Early Jurassic. The lithology consists of fissile mudstones and siltstones, with the lower part having thin beds of limestone and the upper part having thin beds of sandstone. The Redcar Mudstone Formation at Wine Haven, Robin Hood's Bay, Yorkshire contains the Global Boundary Stratotype Section and Point A Global Boundary Stratotype Section and Point (GSSP) is an internationally agreed upon reference point on a stratigraphic section which defines the lower boundary of a stage on the geologic time scale. The effort to define GSSPs is conducted ... (GSSP) for the base of the Pliensbachian. References {{reflist Further reading * J. Gründel, A. Kaim, A. Nützel and C. T. S. Little. 2011. Early Jurassic Gastropods form England. Palaeontology 54(3):481-510 Geologic formations of England Jurassic Sys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Staithes Sandstone Formation
The Staithes Sandstone Formation is a geological formation in North Yorkshire, England. Part of the Lias Group, it is Pliensbachian in age. The lithology consists of silty sandstones, with varying argillaceousness. Typically intensely bioturbated and with many bedding Bedding, also known as bedclothes or bed linen, is the materials laid above the mattress of a bed for hygiene, warmth, protection of the mattress, and decorative effect. Bedding is the removable and washable portion of a human sleeping environm ... structures. References Pliensbachian Stage Jurassic England Jurassic System of Europe {{UK-geologic-formation-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cleveland Ironstone Formation
The Cleveland Ironstone Formation is a sequence of marine ironstone seams interbedded with shale and siltstone units which collectively form a part of the Lower Jurassic System of rocks underlying Cleveland in North Yorkshire. Exploitation of the ironstone seams became a major driving force behind the industrialisation of the Teesside district during the mid- to late-1800s. Based on the stratigraphy of the formation, the Cleveland Ironstone was found to belong within the Upper Pliensbachian (Domerian) universal stage. Ironstone seams and accompanying shales may be highly fossiliferous with remains so abundant in parts as to form well-developed shell-beds. Analysis reveals a wealth of shallow-water marine species, some in life position, along with trace fossils including ''Rhizocorallium'' burrows well exposed at Old Nab, east of Staithes. Stratigraphy Formerly classified as part of the Middle Lias, these strata were deposited over a period of about 2 million years, as soft s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cleveland Basin
The Cleveland Basin is a sedimentary basin in Yorkshire, England. Formed initially by rifting during the Mississippian period of the Early Carboniferous. It is West–East trending and lies between the intrabasinal highs of the Askrigg Block and the Market Weighton Axis, passing eastwards offshore into the Sole Pit Basin. It contains a thick development of the Bowland Shale, which has been assessed as being a major potential source of shale gas. It was inverted towards the end of the Carboniferous and most of the Upper Carboniferous sequence was eroded off. Subsequent deposition has also created a thick fill of Jurassic and Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ... sediments. References Sedimentary basins of Europe {{UK-geology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scunthorpe Mudstone
The Scunthorpe Mudstone is a geologic formation in England. It preserves plesiosaur fossils dating back to the Late Triassic (Rhaetian) to Early Jurassic (Hettangian) period. It predominantly consists of grey mudstone with thin beds of argillaceous limestone and calcareous siltstone. The Ichthyosaur '' Wahlisaurus'' is known from the formation. As is the holotype specimen of the dinosaur '' Sarcosaurus''. See also * List of fossiliferous stratigraphic units in England See also * Lists of fossiliferous stratigraphic units in Europe * Lists of fossiliferous stratigraphic units in the United Kingdom References * {{DEFAULTSORT:Fossiliferous stratigraphic units in England England United Kingdom geology-rel ... References Further reading * R. Forrest. 1998. A possible early elasmosaurian plesiosaur from the Triassic/Jurassic boundary of Nottinghamshire. Mercian Geologist 14(3):135-143 Geologic formations of England Jurassic System of Europe Triassic System of Eu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marlstone Rock Formation
The Marlstone Rock Formation is a geological formation in England. It dates to the Early Jurassic, it consists of "Sandy, shell-fragmental and ooidal ferruginous limestone interbedded with ferruginous calcareous sandstone, and generally subordinate ferruginous mudstone beds", with ironstone. References {{reflist Geologic formations of England Jurassic England Early Jurassic Europe Pliensbachian Stage Toarcian Stage Formations Jurassic System of Europe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whitby Mudstone
The Whitby Mudstone is a Toarcian (Early Jurassic; ''Falciferum''-''Bifrons'' in regional chronostratigraphy) geological formation in Yorkshire and Worcestershire, England.Whitby Mudstone at .org The formation, part of the , is present in the and |
Blue Lias
The Blue Lias is a geological formation in southern, eastern and western England and parts of South Wales, part of the Lias Group. The Blue Lias consists of a sequence of limestone and shale layers, laid down in latest Triassic and early Jurassic times, between 195 and 200 million years ago. The Blue Lias is famous for its fossils, especially ammonites. Its age corresponds to the Rhaetian to lower Sinemurian stages of the geological timescale, thus fully including the Hettangian stage. It is the lowest of the three divisions of the Lower Jurassic period and, as such, is also given the name ''Lower Lias''. Stratigraphically it can be subdivided into three members: the Wilmcote Limestone, Saltford Shale and Rugby Limestone. Lithology and facies The Blue Lias comprises decimetre scale alternations of argillaceous limestone and mudstone. These alternations are caused by short-term climatic variations during the Early Jurassic attributed to orbital forcing ( Milankovitch cycles). T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charmouth Mudstone
The Charmouth Mudstone Formation is a geological formation in England. It preserves fossils dating back to the early part of the Jurassic period (Sinemurian–Pliensbachian). It forms part of the lower Lias Group. It is most prominently exposed at its type locality in cliff section between Lyme Regis and Charmouth (alongside the underlying Blue Lias) but onshore it extends northwards to Market Weighton, Yorkshire, and in the subsurface of the East Midlands Shelf and Wessex Basin. The formation is notable for its fossils, including those of ammonites and marine reptiles and rare dinosaur remains. The formation played a prominent role in the history of early paleontology, with its Lyme Regis-Charmouth exposure being frequented by fossil collectors including Mary Anning. Stratigraphy Shales With Beef Member The Shales With Beef Member is around 28–30 metres thick in the Lyme Regis-Charmouth region and predominantly consists of thinly bedded medium to dark grey mudstone, block ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyrham Formation
The Dyrham Formation is a geologic formation in England. It preserves fossils dating back to the early part of the Jurassic period (Pliensbachian). See also * List of fossiliferous stratigraphic units in England See also * Lists of fossiliferous stratigraphic units in Europe * Lists of fossiliferous stratigraphic units in the United Kingdom References * {{DEFAULTSORT:Fossiliferous stratigraphic units in England England United Kingdom geology-rel ... References * Jurassic England Pliensbachian Stage Jurassic System of Europe {{England-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
