نتایج جستجو برای: jurassic

تعداد نتایج: 4540  

2012
Oliver W. M. Rauhut Alexander M. Heyng Adriana López-Arbarello Andreas Hecker

BACKGROUND Rhynchocephalians, the sister group of squamates (lizards and snakes), are only represented by the single genus Sphenodon today. This taxon is often considered to represent a very conservative lineage. However, rhynchocephalians were common during the late Triassic to latest Jurassic periods, but rapidly declined afterwards, which is generally attributed to their supposedly adaptive ...

2014
G. E. Shephard N. Flament S. Williams M. Seton M. Gurnis R. D. Müller

The circum-Arctic is one of themost tectonically complex regions of the world, shaped by a history of ocean basin opening and closure since the Early Jurassic. The region is characterized by contemporaneous large-scale Cenozoic exhumation extending from Alaska to the Atlantic, but its driving force is unknown. We show that the mantle flow associated with subducted slabs of the South Anuyi, Mong...

2000
M. E. Lepitre J. K. Mortensen S. J. Jordan

The Bulkley Suite of intrusions are spatially associated with numerous important mineral occurrences in westcentral British Columbia. Previous K-Ar dating studies indicated that the Bulkley Suite ranges in age from 70 to 84 Ma (Carter, 1981). The purpose of this study is to better constrain the timing of Bulkley Suite magmatism and associated mineralization in the northern Tahtsa Lake District....

2016

Triassic and Jurassic carbonates across the Middle East host large amounts of hydrocarbons, but the degree of sedimentary heterogeneity across different scales in carbonates varies significantly. In this study we investigate the regional evolution of a carbonate ramp across the Late Triassic to Early Jurassic on the Musandam Peninsula (UAE and Oman) in a series of wadis, 45 km apart. Lithostrat...

The Hojdek Formation in the Kale-shur area consists of alternation of fine quartz arenitic-arkosic sandstones with dark gray to green shales and coal seams. This formation includes relatively well-preserved plant macrofossils which are studied here for the first time. 15 species of 9 genera belong to different orders such as Equisetales, Filicales, Sycadales and Pinales have been determined in ...

Journal: :Proceedings of the National Academy of Sciences 2012

2017
Novella L. Razzolini Matteo Belvedere Daniel Marty Géraldine Paratte Christel Lovis Marielle Cattin Christian A. Meyer

A new ichnospecies of a large theropod dinosaur, Megalosauripus transjuranicus, is described from the Reuchenette Formation (Early-Late Kimmeridgian, Late Jurassic) of NW Switzerland. It is based on very well-preserved and morphologically-distinct tracks (impressions) and several trackways, including different preservational types from different tracksites and horizons. All trackways were excav...

2017
Philip D. Mannion Ronan Allain Olivier Moine

Brachiosauridae is a clade of titanosauriform sauropod dinosaurs that includes the well-known Late Jurassic taxa Brachiosaurus and Giraffatitan. However, there is disagreement over the brachiosaurid affinities of most other taxa, and little consensus regarding the clade's composition or inter-relationships. An unnamed partial sauropod skeleton was collected from middle-late Oxfordian (early Lat...

2013
Chaofan Shi Yongjie Wang Dong Ren

Neuroptera has a history of more than 270 million years, exhibiting broadest familial diversity in the Mesozoic, especially in the Jurassic and Cretaceous (New 1989; Ponomarenko 2002; Grimaldi & Engel 2005; Winterton et al. 2010). Grammolingiidae is a small family with limited distribution temporally and geographically, only recorded in the Jurassic of all East Asia and the southern Central Asi...

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