44 research outputs found
New early Triassic Lingulidae (Brachiopoda) genera and species from South China
Two new genera, Sinolingularia gen. nov. and Sinoglottidia gen. nov., together with three new species, Sinolingularia huananensis gen. et sp. nov., Sinolingularia yini gen. et sp. nov. and Sinoglottidia archboldi gen. et sp. nov., are described on the basis of a large collection of well-preserved specimens from several sections straddling the Permian - Triassic boundary in South China. <br /
Costatoria (Costatoria?) subrotunda (BITTNER, 1901) a Smithian (Lower Triassic) marker from Tethys
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Marine fossil assemblages from Upper Permian to lowermost Triassic in the western Dolomites (Italy)
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ComunitĂ di piattaforma del Bartoniano e del Priaboniano (Eocene medio, Eocene superiore; Colli Berici, Vicenza): un approccio paleoecologoco.
Guida all'escursione. Riunione annuale Gruppo Palaeobenthos, Mossano (Vi) , ottobre 1997, pp. 1-33
The Anisian macroflora from KĂŒhwiesenkopf / Monte PrĂ della Vacca in the Northern Dolomites (Italy)
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Jurassic Monster Polar Shift Confirmed by Sequential Paleopoles From Adria, Promontory of Africa
Jurassic paleomagnetic data from North America have long been contentious, generating ambiguities in the shape of the globalâcomposite apparent polar wander path. Here we show from a restudy of two subdivisions of the Late Jurassic Morrison Formation at the classic locality at Norwood on the Colorado Plateau that the derived paleopoles reflect variable overprinting probably in the Cretaceous and are of limited value for apparent polar wander determination. We instead assembled an updated set of Jurassic paleopoles from parauthocthonous Adria, the African promontory, using primary paleomagnetic component directions derived from stratigraphically superposed intervals and corrected for sedimentary inclination error. These paleopoles are found to be in superb agreement with independent igneous paleopoles from the literature across the soâcalled Jurassic monster polar shift, which in North American coordinates is a jump of ~30° arc distance from the 190â to 160âMa stillstand pole at 79.5°N 104.8°E to a 148 ± 3.5âMa pole at 60.8°N 200.6°E defined by four Adria sedimentary paleopoles and the published Ithaca, Hinlopenstretet, and SwartsruggensâBumbeni igneous paleopoles. The implied high rate of polar motion of ~2.5°/Myr across the monster shift is compatible with maximum theoretical estimates for true polar wander. We include a critique of published Jurassic paleomagnetic data that have been variably used in reference APWPs but that as a result of their low quality muted the real magnitude of the Jurassic monster shift. Finally, we provide paleocontinental reconstructions to describe examples of the bold signature that the monster polar shift left in the distribution of climateâsensitive sedimentary
facies worldwide