نتایج جستجو برای: middle eocene
تعداد نتایج: 158502 فیلتر نتایج به سال:
An integrated study including magnetostratigraphy, larger benthic foraminifera and calcareous nannofossil biostratigraphy is presented herein. This work was performed in shallow marine siliciclastics rich foraminifera, around the Ypresian/Lutetian boundary Ésera valley (South-Central Pyrenees). Although content studied interval low, not allowing a precise Y/L to be recognised, taxa found are en...
A skull of a new pelecaniform bird is described from the Middle Eocene of Messel (Germany). Masillastega rectirostris gen. et sp. nov. is tentatively referred to the Sulidae (boobies and gannets). If this assignment is correct, the new taxon would represent the earliest fossil record of the family, preceding Sula ronzoni Milne−Edwards, 1867 from the lowermost Oligocene of France by about 15 mil...
Deinodryinus veltenisp. n. is described from middle Eocene Baltic amber. The species differs from other fossil Palaearctic species of Deinodryinus Perkins owing to the shape of the antenna (clavate, with distal part very thickened), the large compound eyes, and the distal part of the stigmal vein much longer than the proximal part. A revision and a key to the fossil Palaearctic species of Deino...
chaldoran area in nw of iran has mesozoic oceanic crust basement. the studied rocks of this region can be divided into three groups: ophiolitic gabbros and pillow lavas, ophiolitic volcanoclastics and eocene lava flows. ophiolitic mafic rocks show continental volcanic arc natures and eocene lava flow shows oib-like nature. during the mesozoic,the chaldoran region was situated in the active cont...
A new species of the extinct bee genus Ctenoplectrella Cockerell (Megachilinae: Ctenoplectrellini) is described and figured from two females preserved in middle Eocene (Lutetian) Baltic amber. Ctenoplectrella phaetonsp. n. is distinguished from its congeners on the basis of its body proportions, integumental sculpturing, wing venation, and pubescence, and is one of the more distinctive members ...
BACKGROUND Molecular clock estimates of crown strepsirhine origins generally advocate an ancient antiquity for Malagasy lemuriforms and Afro-Asian lorisiforms, near the onset of the Tertiary but most often extending back to the Late Cretaceous. Despite their inferred early origin, the subsequent evolutionary histories of both groups (except for the Malagasy aye-aye lineage) exhibit a vacuum of ...
The tectonic opening of the Tasmanian Gateway and Drake Passage represented crucial geographic requirements for Cenozoic development Antarctic Circumpolar Current (ACC). Particularly complexity has hampered exact dating deepening phases, consequential onset throughflow ACC. One obstacles is putting key regional events, recorded in southern Patagonian sediments, absolute time. For that purpose, ...
A late Eocene erosion sudace of low relief, which extended throughout south-central Colorado, provides a post-Laramide, pre-Oligocene, regional structural datum. The age and geomorphic character of the sudace are documented for an area of more than 10,400 km2 in the southern Front Range, Rampart Range, South Park, Thirtynine Mile volcanic field, southern Mosquito Range, upper Arkansas River val...
India's northward flight and collision with Asia was a major driver of global tectonics in the Cenozoic and, we argue, of atmospheric CO(2) concentration (pCO(2)) and thus global climate. Subduction of Tethyan oceanic crust with a carpet of carbonate-rich pelagic sediments deposited during transit beneath the high-productivity equatorial belt resulted in a component flux of CO(2) delivery to th...
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