Results 41 to 50 of about 2,123 (183)

The Unexpected Discovery of Paleocene? Coals in Outcrops Thought to Be Cambrian, Al Huqf, Oman

Journal of Petroleum Geology, EarlyView.
ABSTRACT Two brown organic deposits were encountered whilst investigating kaolinitic claystones thought to occur at the base of a Cambrian formation at outcrop. The age of these organic deposits is probably Paleocene from palynology. Organic petrography shows that they are subbituminous coals with some oil source potential.
Mohammed H. Al Kindi, Alan P. Heward, Lorraine B. Eglinton, Steve R. Packer, Darrin T. Stead   +4 more
wiley   +1 more source

Quantitative and Nuanced Approaches Elucidate Carbon Isotope Records

Geochemistry, Geophysics, Geosystems
Earth scientists have leveraged carbon isotope records to interpret Earth history and establish chronostratigraphic frameworks for decades (e.g., Halverson et al., 2005, https://doi.org/10.1130/b25630.1; Kaufman & Knoll, 1995, https://doi.org/10.1016 ...
Cedric J. Hagen
doaj   +1 more source

Petrographic and mineralogical characteristics of diagenetic overprinting in Neoproterozoic diamictites from Murchisonfjorden, Nordaustlandet, Svalbard

Mineralogia
The diagenetic processes exhibited by the Neoproterozoic diamictites from Murchisonfjorden (Nordaustlandet, NE Svalbard) are presented. Diamictite samples from the Cryogene Polarisbreen Group - the Petrovbreen Member of the Elbobreen Formation and the ...
Bal Szczepan, Nejbert Krzysztof, Michalski Krzysztof, Domańska-Siuda Justyna, Manby Geoffrey, Hołda-Michalska Aleksandra, Sláma Jiři   +6 more
doaj   +1 more source

Lithostratigraphy of the Portfjeld Group (Ediacaran – lowermost Cambrian) of North Greenland

GEUS Bulletin
The Portfjeld Formation, as originally defined, is the lowermost lithostratigraphic unit of the mainly Lower Palaeozoic Franklinian Basin in southern Peary Land, central North Greenland.
Jon R. Ineson, John S. Peel, Sebastian Willman, Elias J. Rugen, Martin Sønderholm, Peter Frykman   +5 more
doaj   +1 more source

A vast Caledonian fan and an Ediacaran arc: the contrasting provenance of Devonian clastics of Brunia (Bohemian Massif) [PDF]

Solid Earth
Brunia is a distinctive crustal block within the European Variscides, composed of a late Neoproterozoic arc complex overlain by Ediacaran–early Cambrian cover sequences.
S. Collett, I. Soejono, T. Kumpan, P. Hanžl, J. Míková, N. Novotná, J. Sláma   +6 more
doaj   +1 more source

Relics of ophiolite-bearing accretionary wedges in NE Brazil and NW Africa: Connecting threads of western Gondwana´s ocean during Neoproterozoic times

Geosystems and Geoenvironment, 2023
Neoproterozoic breakup of Rodinia resulted in the formation of several oceanic realms between dispersing cratons, which were later consumed during the assembly of Gondwana. In its western portion, the interior orogenic belts of Gondwana formed during the
Lauro Cézar M. de Lira Santos, Fabrício A. Caxito, Merlain H. Bouyo, Sonia Ouadahi, Kawther Araïbia, Geysson A. Lages, Glenda L. Santos, João Paulo A. Pitombeira, Peter A. Cawood   +8 more
doaj   +1 more source

MAGMATIC SOURCES OF THE EVOLVING CONTINENTAL TECTONOSPHERE IN INDIA: GENERATION OF ALKALINE IGNEOUS COMPLEXES WITH CARBONATITES IN THE SAMALPATTI (SOUTHERN INDIA) AND AMBA DONGAR (WESTERN INDIA) MASSIFS

Геодинамика и тектонофизика
Neoproterozoic Samalpatti and Cretaceous-Paleogene Amba Dongar massifs are considered to evaluate the change of sources of carbonatite magmatism in evolving tectonosphere of India. The inherited character of Ba and Sr distribution components is traced in
S. V. Rasskazov, T. A. Yasnygina, K. R. Hari, I. S. Chuvashova, E. V. Saranina   +4 more
doaj   +1 more source

Comprehensive evaluation of Neoproterozoic source rocks formation

Georesursy
Based on comprehensive analysis of geological, geochemical, and paleotectonic settings, the conditions for the formation of Neoproterozoic oil and gas source rocks of the Earth are analyzed. A brief review of oil and gas fields in Eastern Siberia, China,
K. A. Sitar, B. V. Georgievskiy, M. A. Bolshakova, R. S. Sautkin   +3 more
doaj   +1 more source

Biological feedbacks as cause and demise of the Neoproterozoic icehouse: astrobiological prospects for faster evolution and importance of cold conditions. [PDF]

PLoS ONE, 2007
Several severe glaciations occurred during the Neoproterozoic eon, and especially near its end in the Cryogenian period (630-850 Ma). While the glacial periods themselves were probably related to the continental positions being appropriate for glaciation,
Pekka Janhunen, Hermanni Kaartokallio, Ilona Oksanen, Kirsi Lehto, Harry Lehto   +4 more
doaj   +1 more source

Sedimentary evolution of Neoproterozoic rift basin in northern Tarim

Petroleum Research, 2017
Based on the outcrop, drilling and seismic data, the sedimentary successions, evolution and hydrocarbon exploration potential of the Neoproterozoic rift basin in the northern Tarim were firstly analyzed.
Lin Wu, Shuwei Guan, Rong Ren, Chunyu Zhang   +3 more
doaj   +1 more source