The Late Jurassic is the third epoch of the Jurassic period, and it spans the geologic time from 161.5 ± 1.0 to 143.1 ± 0.6 million years ago (Ma), which is preserved in Upper Jurassic strata.Owen 1987.
In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age. In the past, Malm was also used to indicate the unit of geological time, but this usage is now discouraged to make a clear distinction between lithostratigraphic and geochronologic/chronostratigraphic units.
Subdivisions The Late Jurassic is divided into three ages, which correspond with the three faunal stages of Upper Jurassic rock: NameLower boundary(Ma)Tithonian 149.2 ± 0.7Kimmeridgian 154.8 ± 0.8Oxfordian 161.5 ± 1.0
Paleogeography
By the Late Jurassic, Pangaea had already broken apart into Laurasia (Eurasia and North America) to the north and Gondwana to the south, divided by the wide Tethys Ocean. During the Late Jurassic, narrow ocean basins formed separating Eastern Gondwana (Antarctica, Australia, India and Madagascar), Western Gondwana (Africa, Arabia and South America) and Laurasia. The young North Atlantic Ocean continues to widen as North America drifts to the north – brought increased moisture to the formerly highly arid subtropical interior of Pangaea. The Wrangellia terrane is accreted to Western North America.
Climate Deep ocean basins covered the poles, inhibiting the formation of polar ice caps. Polar summers were ice-free. The circulation of ocean currents between the high and low latitudes contributed to a generally warmer climate than today. Europe became progressively more arid over the Late Jurassic.
Life forms This epoch is well known for many famous types of dinosaurs, such as the sauropods, the theropods, the thyreophorans, and the ornithopods. Other animals, such as some crocodylomorphs and the first birds, appeared in the Jurassic. Listed here are only a few of the many Jurassic animals: NameDescriptionWhere foundAllosaurusThe most common Late Jurassic theropodNorth America, also present in EuropeAnurognathusOne of the smallest pterosaursEuropeApatosaurusA large herbivorous sauropod dinosaurNorth AmericaArchaeopteryxA bird-like maniraptoranEuropeBarosaurusAn exceptionally long herbivorous sauropod dinosaurNorth AmericaBrachiosaurusA massive herbivorous sauropod dinosaurNorth AmericaBrachytrachelopanA small herbivorous sauropod dinosaurSouth AmericaBrontosaurusA large herbivorous sauropod dinosaurNorth AmericaCamarasaurusA large herbivorous sauropod dinosaurNorth AmericaCamptosaurusAn ornithopodNorth America and possibly EuropeCeratosaurusA medium-sized Jurassic carnivoreNorth America, Europe, and possibly AfricaChaoyangsaurusAn early marginocephalian dinosaurAsiaCompsognathusA small theropodEuropeDakosaurusA medium-sized sea-going crocodylomorphEuropeDicraeosaurusA large herbivorous sauropod dinosaurAfricaDiplodocusAn exceptionally long herbivorous sauropod dinosaurNorth AmericaDryosaurusAn ornithopodNorth AmericaElaphrosaurusA medium-sized Jurassic carnivoreAfricaEpanteriasA massive carnivore (possibly just Allosaurus)North AmericaEuropasaurusA small herbivorous sauropod dinosaurEuropeGargoyleosaurusA thyreophoranNorth AmericaGiraffatitanA large sauropod (formerly recognized as a species of Brachiosaurus)AfricaJuramaiaA basal mammalAsiaKentrosaurusA thyreophoranAfricaLiopleurodonA medium-sized sea-going pliosaurEuropeMaraapunisaurusPossibly among the largest sauropod dinosaurs ever knownOphthalmosaurusA very common sea-going ichthyosaurEurope and North AmericaOrnitholestesA small theropodNorth AmericaPerisphinctesAn ammonitePterodactylusA short-tailed pterosaurEuropeRhamphorhynchusA long-tailed pterosaurEuropeSaurophaganaxA giant carnivore; possibly the largest land predatorof the Jurassic (possibly a synonym of Allosaurus)North AmericaStegosaurusA thyreophoran North America and EuropeSupersaurusPossibly the longest sauropod dinosaur of them allTorvosaurusA large Jurassic carnivoreNorth America and EuropeTuojiangosaurusA thyreophoranAsiaYangchuanosaurusA large theropodAsiaYinlongAn early marginocephalian dinosaurAsia
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