Results 81 to 90 of about 12,978 (245)

Conditions and timing for the precipitation of early marine diagenetic dolomite in the Triassic Dolomia Principale (northern Italy)

Sedimentology, EarlyView.
ABSTRACT Thermodynamic constraints and empirical evidence often suggest that fabric‐retentive replacement dolomites are stable carbonate minerals that preserve ancient seawater properties. This study evaluates this hypothesis by examining the Upper Triassic Dolomia Principale in Northern Italy.
Vivien Folliot, Giovanna Della Porta, Mathias Mueller, Fabrizio Berra, Benjamin F. Walter, Aratz Beranoaguirre, Sylvia Riechelmann, Oskar Schramm, Adrian Immenhauser   +8 more
wiley   +1 more source

Ediacaran metazoan fossil record from South America and its implications in the studies about origin and complexification of animal life [PDF]

Geologia USP. Série Científica, 2013
The Ediacaran Period marks the first appearance of complex macroscopic organisms in the fossil record. Current evidence indicates that Ediacara biota is composed of animals, groups of extinct giant protists, algae and other organisms without proven ...
Bruno Becker Kerber, Ana Lucia Zucatti da Rosa, Sandra Garcia Gabas, Juliana de Moraes Leme, Mírian Liza Alves Forancelli Pacheco   +4 more
doaj   +1 more source

The puzzle assembled: Ediacaran guide fossil Cloudina reveals an old proto-Gondwana seaway [PDF]

, 2014
During the Ediacaran the Clymene Ocean separated the Laurentia, Amazonia, and Rio Apa cratons from several landmasses to the west forming the proto-Gondwana supercontinent.
Strikis, Nicolás, Strikis, Pedro C., Warren, L. V. [UNESP], Poire, Daniel Gustavo, Riccomini, Claudio, Quaglio, Fernanda, Simoes, Marcelo, Poire, D. G., Simoes, M. G. [UNESP], Riccomini, C., Quaglio, F., Anelli, Luis E., Strikis, N. M., Anelli, L. E., Strikis, P. C., Warren, L. V., Simoes, M. G., Warren, Lucas V., Quaglio, F. [UNESP]   +18 more
core   +1 more source

Arumberiamorph structure in modern microbial mats: implications for Ediacaran palaeobiology [PDF]

BSGF - Earth Sciences Bulletin, 2017
In the course of studying modern halotolerant microbial mats in salterns near the village of Kervalet, western France, we observed fanning-out and curved series of macroscopic ridges on the surface of a newly formed biofilm.
Kolesnikov Anton V., Danelian Taniel, Gommeaux Maxime, Maslov Andrey V., Grazhdankin Dmitriy V.   +4 more
doaj   +1 more source

Discovery of the oldest bilaterian from the Ediacaran of South Australia

Proceedings of the National Academy of Sciences of the United States of America, 2020
Significance The transition from simple, microscopic forms to the abundance of complex animal life that exists today is recorded within soft-bodied fossils of the Ediacara Biota (571 to 539 Ma).
S. Evans, I. Hughes, J. Gehling, M. Droser   +3 more
semanticscholar   +1 more source

The Ediacaran−Cambrian transition in the southern Great Basin, United States

GSA Bulletin, 2022
The Ediacaran−Cambrian boundary strata in the Great Basin of the southwestern United States record biological, geochemical, and tectonic change during the transformative interval of Earth history in which metazoans diversified. Here, we integrate new and
E. Smith, L. Nelson, Nizhoni O’Connell, A. Eyster, Mary C Lonsdale   +4 more
semanticscholar   +1 more source

Salt Range Formation of Pakistan Preserves Unique Record of Volcanic Fertilization During the Ediacaran Shuram Excursion

Terra Nova, EarlyView.
ABSTRACT Thin, discontinuous, organic‐rich oil shale beds in the siliciclastic‐evaporitic Salt Range Formation (SRF) of Pakistan are of approximate Neoproterozoic to Cambrian age based on stratigraphic constraints. The beds are enriched (26–43 wt.% total organic carbon, TOC) in aliphatic organic matter (OM) of low thermal maturity despite their ...
Paul C. Hackley, Ryan J. McAleer, Jay M. Thompson, Brett J. Valentine, Imran Khan   +4 more
wiley   +1 more source

Revisiting Ediacaran sulfur isotope chemostratigraphy with in situ nanoSIMS analysis of sedimentary pyrite

Geology, 2021
Reconstructions of ancient sulfur cycling and redox conditions commonly rely on sulfur isotope measurements of sedimentary rocks and minerals. Ediacaran strata (635–541 Ma) record a large range of values in bulk sulfur isotope difference (Δ34S) between ...
Wei Wang, Yongliang Hu, A. Muscente, Huan Cui, C. Guan, J. Hao, Chuan-Ming Zhou   +6 more
semanticscholar   +1 more source

Multi‐Mineral Geochronology Across the Neoproterozoic Brasília Nappe Stack: Constraints on Thermal Resetting and Metamorphic Architecture

Terra Nova, EarlyView.
ABSTRACT The Southern Brasília Orogen formed during Western Gondwana's final assembly and comprises nappe systems piled against the São Francisco Craton. We present new rutile U–Pb ages from the lowermost Canastra Group (> 2.2 Ga) and the uppermost Carrancas Group (~560 Ma), integrated with published zircon, monazite, garnet, and mica ages from the ...
Rodrigo Irineu Cerri, Alex J. Choupina A. Silva, Tamiris Pagotti Gonçalves Pinto, Rodrigo Prudente de Melo, George Luiz Luvizotto, Regiane Andrade Fumes, Fabrício de Andrade Caxito, Renato Moraes   +7 more
wiley   +1 more source

Lithochemical features of the rocks of the Hrushka Formation of the lower vend of the Podillya structural-facies zone

Мінеральні ресурси України
Silicate analyzes of siltstones, argillites, sandstones, gravelites, and conglomerates were used to examine the lithochemical features of the clastic rocks of the Hrushka Formation.
T. M. Sokur, O. A. Sukhov, I. V. Vasileva   +2 more
doaj   +1 more source