نتایج جستجو برای: cretaceous rocks

تعداد نتایج: 30195  

2004
Eugene P. GUROV Christian KOEBERL

available online at http://meteoritics.org 1495 © Meteoritical Society, 2004. Printed in USA. Shocked rocks and impact glasses from the El’gygytgyn impact structure, Russia Eugene P. GUROV1 and Christian KOEBERL2* 1Institute of Geological Sciences, National Academy of Sciences of the Ukraine, 55b Oles Gontchar Street, Kiev 01054, Ukraine 2Department of Geological Sciences, University of Vienna,...

Journal: :علوم 0

three granitoid bodies, shirkuh batholith, kaffe abad and ader bolandan are exposed in nw yazd, cutting across the naiband formation (upper triassic), and overlain by cretaceous formations. shirkuh batholith is most likely of jurassic age. it seems to be the first and the most significant episode of magmatism in studied area which occurred in middle jurassic (late cimmerian) time. on the other ...

Ghasemi, habiballah, Hedayaty Kharagh, seyedeh nafiseh, Kazemi Hassanvand, zakiyeh,

The Late cretaceous dioritic intrusions of Filshour and Goft in southwest of Sabzevar are situated in the northern edge of central Iran zone. The rocks of these plutons show porphyry, granular, ophitic and subophitic textures and are composed of amphibole, plagioclase and clinopyroxene (in diorites), along with quartz (in quartz diorites). The amphiboles of these rocks are in the group of calci...

1996
SE Spain

AB STRACT: Glauconite and Ca phosphate peloids occur in Jurassic and Cretaceous bioclastic carbonate rocks from pelagic swell sequences of the Algayat-Crevillente Unit (Subbetic Zone). The size and morphology of the peloids are controlled by the bioclasts. The glauconite in both stratigraphic positions is K rich (>0.69 atoms p.f.u.) and shows well-defined 10 AÊ lattice fringes. Poorly crystalli...

2013
Mohammed Hail Hakimi Mohamed Ragab Shalaby Wan Hasiah Abdullah

Biyad Formation is mainly made up of clastic sediments that contain substantial amount of proven crude oil in the eastern Yemen. The Byiad clastic is divided into Upper and Lower Biyad clastic units. Several vertical wells have been drilled and penetrated this formation. This study is concerned with the petrophysical evaluation by means of well log data of the Lower Cretaceous rocks at the East...

Journal: :Science 1998
Sereno Beck Dutheil Gado Larsson Lyon Marcot Rauhut Sadleir Sidor Varricchio Wilson

Fossils discovered in Lower Cretaceous (Aptian) rocks in the Tenere Desert of central Niger provide new information about spinosaurids, a peculiar group of piscivorous theropod dinosaurs. The remains, which represent a new genus and species, reveal the extreme elongation and transverse compression of the spinosaurid snout. The postcranial bones include blade-shaped vertebral spines that form a ...

2012
M. L. G. Tejada G. Ravizza K. Suzuki F. S. Paquay

The Early Cretaceous Greater Ontong Java Event in the Pacific Ocean may have covered ca. 1% of the Earth's surface with volcanism. It has puzzled scientists trying to explain its origin by several mechanisms possible on Earth, leading others to propose an extraterrestrial trigger to explain this event. A large oceanic extraterrestrial impact causing such voluminous volcanism may have traces of ...

2016
Georgina L. Bennett

1 REGIONAL GEOLOGY 2 The northern California Coast Ranges are composed the Franciscan Complex, a penetratively 3 sheared set of metasedimentary rocks forming an accretionary prism. The Franciscan complex is 4 subdivided into three broad belts that young to the west: the Eastern, Central and Coastal belts, 5 reflecting the cumulative accretion of oceanic sediments to western North America (McLau...

2012
László Makádi Michael W. Caldwell Attila Ősi

Mosasauroids are conventionally conceived of as gigantic, obligatorily aquatic marine lizards (1000s of specimens from marine deposited rocks) with a cosmopolitan distribution in the Late Cretaceous (90-65 million years ago [mya]) oceans and seas of the world. Here we report on the fossilized remains of numerous individuals (small juveniles to large adults) of a new taxon, Pannoniasaurus inexpe...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2015
Toby Tyrrell Agostino Merico David Ian Armstrong McKay

Most paleo-episodes of ocean acidification (OA) were either too slow or too small to be instructive in predicting near-future impacts. The end-Cretaceous event (66 Mya) is intriguing in this regard, both because of its rapid onset and also because many pelagic calcifying species (including 100% of ammonites and more than 90% of calcareous nannoplankton and foraminifera) went extinct at this tim...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید