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Karoo-Ferrar

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The Karoo and Ferrar Large Igneous Provinces (LIPs) are two large igneous provinces in Southern Africa and Antarctica respectively, collectively known as the Karoo-Ferrar , Gondwana , or Southeast African LIP, associated with the initial break-up of the Gondwana supercontinent at c. 183 Ma . Its flood basalt mostly covers South Africa and Antarctica but portions extend further into southern Africa and into South America , India , Australia and New Zealand .

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20-657: Karoo-Ferrar formed just prior to the breakup of Gondwana in the Lower Jurassic epoch, about 183 million years ago; this timing corresponds to the early Toarcian anoxic event and the Pliensbachian-Toarcian extinction . It covered about 3 x 10 km. The total original volume of the flow, which extends over a distance in excess of 6000 km (4000 km in Antarctica alone), was in excess of 2.5 x 10 km (2.5 million cubic kilometres). The Ferrar LIP

40-893: A peak between 183 to 173 Ma but produced continued magmatism between 168 to 141 Ma . By 184 to 175 Ma the Karoo magmatism had spread to Namibia, Lesotho, Lebombo, and the Ferrar province in Antarctica. The Karoo LIP ended 145 Ma with peripheral eruptions in Patagonia, the Antarctica Peninsula, northern South Africa, Kerala in India, and southeast Australia. The Karoo Province uplifted southern Africa c. 1.5 km (0.93 mi) and broke East Gondwana (India, Antarctica, and Australia) away from West Gondwana (South America and Africa) beginning in

60-657: A problem that makes correlation between sections in different parts of the world difficult. If this biostratigraphical indicator is used, then technically the Lias Group —a lithostratigraphical division—spans the Jurassic / Triassic boundary. There are extensive Liassic outcrops around the coast of the United Kingdom , in particular in Glamorgan , North Yorkshire and Dorset . The 'Jurassic Coast' of Dorset

80-564: Is notable for long-distance transport and the Karoo LIP for its large volume and chemical diversity. The igneous activity of the Karoo LIP began c. 204 Ma at the northern margin of the province. The long-lasting Chon-Aike Province in Patagonia, the Antarctic Peninsula, and Ellsworth Land was activated c. 190 Ma in an unstable tectonic environment in which both extension and subduction occurred. Chon-Aike had

100-524: Is often associated with the pioneering work of Mary Anning of Lyme Regis . The facies of the Lower Jurassic in this area are predominantly of clays , thin limestones and siltstones , deposited under fully marine conditions. Lias Group strata form imposing cliffs on the Vale of Glamorgan coast, in southern Wales . Stretching for around 14 miles (23 km) between Cardiff and Porthcawl ,

120-542: Is probably paraphyletic ). All these plesiosaurs had medium-sized necks and large heads. In the Toarcian , at the end of the Early Jurassic, the thalattosuchians (marine " crocodiles ") appeared, as did new genera of ichthyosaurs ( Stenopterygius , Eurhinosaurus , and the persistently primitive Suevoleviathan ) and plesiosaurs (the elasmosaurs (long-necked) Microcleidus and Occitanosaurus , and

140-696: The Karoo Supergroup of southern Africa and the Serra Geral basalts of central South America." These continental tholeiites are indicative of a large-scale extensional rift system and associated Middle Jurassic magmatic activity linked to the break-up of Gondwana 25 m.y. later, when East Antarctica separated from Africa, and the Mozambique Basin opened. Included in the supergroup are the Ferrar Dolerite sills and dykes ,

160-668: The West Country ); the Cornish would pronounce the layers of limestone as ' laiyers ' or ' lias '; leac is Gaelic for "flat stone". There has been some debate over the actual base of the Hettangian Stage, and so of the Jurassic System itself. Biostratigraphically , the first appearance of psiloceratid ammonites has been used; but this depends on relatively complete ammonite faunas being present,

180-518: The pliosaur Hauffiosaurus ). On land, a number of new types of dinosaurs—the heterodontosaurids , scelidosaurs , stegosaurs , and tetanurans —appeared, and joined those groups like the coelophysoids , prosauropods and the sauropods that had continued over from the Triassic. Accompanying them as small carnivores were the sphenosuchian and protosuchid crocodilians. In the air, new types of pterosaurs replaced those that had died out at

200-410: The Antarctic Peninsula. This phase of magmatism resulted in extension and rift between Australia and Antarctica, Australia and Lord Howe Rise , and Mary Byrd Land and New Zealand. According to Robert John Pankhurst , "The Ferrar Supergroup is well known as being representative of a Middle Jurassic (and partly later), Gondwana-wide continental flood basalts event which includes Tasmanian dolerites ,

220-536: The Black Jura does not exactly coincide with the chronostratigraphic boundaries of the Lower Jurassic. In addition, the term lias , which was formerly frequently used (and sometimes is today) as a synonym , should no longer be used in connexion with the South German Jurassic. Instead, the term lias , or North German Lias , should be reserved for the roughly equivalent lithostratigraphic unit in

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240-681: The Kirkpatrick Basalts, and the volcanogenic Carapace Sandstone and Mawson Formation . Lower Jurassic The Early Jurassic Epoch (in chronostratigraphy corresponding to the Lower Jurassic Series ) is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic–Jurassic extinction event , 201.3 Ma (million years ago), and ends at

260-1519: The North German Jurassic. The deposition of the Black Jurassic took place about 199 to 175 million years ago. The Black Jurassic follows the lithostratigraphic unit of the Keuper and is superimposed on the lithostratigraphic group of the Brown Jurassic . See also [ edit ] White Jurassic Literature [ edit ] Gert Bloos, Gerd Dietl & Günter Schweigert: Der Jura Süddeutschlands in der Stratigraphischen Tabelle von Deutschland 2002. Newsletters on Stratigraphy, 41(1–3): 263–277, Stuttgart, 2005, ISSN   0078-0421 Eckhard Mönnig: Der Jura von Norddeutschland in der Stratigraphischen Tabelle von Deutschland 2002. Newsletters on Stratigraphy, 41(1–3): 253–261, Stuttgart, 2005. Friedrich August Quenstedt: Das Flözgebirge Würtembergs. Mit besonderer Rücksicht auf den Jura . Verlag der Laupp’schen Buchhandlung, Tübingen, 1843. External links [ edit ] Deutsche Stratigraphische Kommission (ed.): Stratigraphische Tabelle von Deutschland 2002 , Potsdam, 2002. ISBN   3-00-010197-7 pdf Geologische Übersicht der Schichtenfolge in Baden-Württemberg (pdf; 183 kB) Archived 15 September 2011 at

280-1015: The end of the Triassic. But in the undergrowth were various types of early mammals, as well as tritylodont synapsids , lizard-like sphenodonts , and early lissamphibians . Black Jurassic [REDACTED] Lithostratigraphy of the South German Jurassic . Abbreviations: Humph.-Fm = Humphriesioolith Formation L.Bk-Fm = Liegende Bankkalk Formation H.Bk-Fm = Hangende Bankkalk Formation Zm-Fm = Zementmergel Formation S.-Fm = Solnhofen Formation Rö.-Fm = Rögling Formation U.-Fm = Usseltal Formation Mö.-Fm = Mörnsheim Formation N.-Fm = Neuburg Formation R.-Fm = Rennertshofen Formation Set of geological formations in Central Europe The Black Jurassic or Black Jura ( German : Schwarzer Jura ) in earth history refers to

300-411: The lowest of the three lithostratigraphic units of the South German Jurassic , the latter being understood not as a geographical, but a geological term in the sense of a lithostratigraphic super group . Formerly and even occasionally today in the popular scientific literature, this term is equated to the chronostratigraphic series of the Lower Jurassic . This is however not quite correct, because

320-785: The opening of the Weddell Sea . In the Cretaceous, some 15 million years after the last Karoo eruption, renewed magmatism was initiated between Mary Byrd Land in Antarctica and New Zealand from where it spread along Gondwana's southern margin, from eastern Australia to the Antarctic Peninsula. Isotopic dating suggests a series of igneous events at 133–131, 124–119, and 113–107 Ma in Australia; 110–99 Ma in Mary Byrd Land; 114-109 and 82 Ma in New Zealand; and 141 and 127 Ma in

340-729: The remarkable layers of these cliffs, situated on the Bristol Channel are a rhythmic decimetre scale repetition of limestone and mudstone formed as a late Triassic desert was inundated by the sea. During this period, ammonoids , which had almost died out at the end-of-Triassic extinction, radiated out into a huge diversity of new forms with complex suture patterns (the ammonites proper). Ammonites evolved so rapidly, and their shells are so often preserved, that they serve as important zone fossils . There were several distinct waves of ammonite evolution in Europe alone. The Early Jurassic

360-490: The start of the Middle Jurassic 174.7 ±0.8 Ma. Certain rocks of marine origin of this age in Europe are called " Lias " and that name was used for the period, as well, in 19th-century geology. In southern Germany rocks of this age are called Black Jurassic . There are two possible origins for the name Lias: the first reason is it was taken by a geologist from an English quarryman 's dialect pronunciation of

380-414: The word "layers"; secondly, sloops from north Cornish ports such as Bude would sail across the Bristol Channel to the Vale of Glamorgan to load up with rock from coastal limestone quarries (lias and Carboniferous limestone from South Wales was used throughout North Devon/North Cornwall as it contains calcium carbonate to 'sweeten' (i.e.neutralise) the acidic Devonian and Carboniferous soils of

400-476: Was an important time in the evolution of the marine reptiles. The Hettangian saw the already existing Rhaetian ichthyosaurs and plesiosaurs continuing to flourish, while at the same time a number of new types of these marine reptiles appeared, such as Ichthyosaurus and Temnodontosaurus among the ichthyosaurs, and Eurycleidus , Macroplata , and Rhomaleosaurus among the plesiosaurs (all Rhomaleosauridae , although as currently defined this group

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