Results 31 to 40 of about 29,296 (274)

A Neoproterozoic Transition in the Marine Nitrogen Cycle [PDF]

Current Biology, 2014
The Neoproterozoic (1000-542 million years ago, Mya) was characterized by profound global environmental and evolutionary changes, not least of which included a major rise in atmospheric oxygen concentrations [1, 2], extreme climatic fluctuations and global-scale glaciation [3], and the emergence of metazoan life in the oceans [4, 5].
Sanchez-Baracaldo, Patricia, Ridgwell, Andy J, Raven, John A.   +2 more
openaire   +3 more sources

Early Neoproterozoic limestones from the Gwna Group, Anglesey [PDF]

, 2010
Limestone megaclasts up to hundreds of metres in size are present within the Gwna Group mélange, North Wales, UK. The mélange has been interpreted as part of a Peri-Gondwanan fore-arc accretionary complex although the age of deposition remains ...
JANA M. HORÁK, Evans, Jane A., Horak, Jana M., JANE A. EVANS   +3 more
core   +1 more source

Perspective of gold-bearing deposits in the ferruginous-siliceous formations of Egypt and Kursk Magnetic Anomaly

RUDN Journal of Engineering Research, 2019
Banded ferruginous-siliceous formations (FSF) are confined to the Precambrian basement of the Arabian-Nubian Shield within the central part of the Eastern Desert of Egypt.
Hani E. Sharafeldin, Alexander A. Vercheba   +1 more
doaj   +1 more source

Neoproterozoic copper cycling, and the rise of metazoans [PDF]

Scientific Reports, 2019
AbstractThe rise of animal life is temporally related to the increased availability of oxygen in the hydrosphere and atmosphere during the Neoproterozoic. However, the earliest metazoans probably needed relatively low oxygen concentrations, suggesting additional environmental and/or biochemical developments were involved.
Parnell, J., Boyce, A.J.
openaire   +4 more sources

Structural peculiarities and geodynamic evolution of Taimyr Peninsula in the Neoproterozoic

Литосфера, 2018
Structural relationships between the Neoproterozoic rock complexes of a continental massif, island arc with rear reef and back-arc basin geodynamic affinities are described and considered in this work based on field observations within the northeastern ...
Sergei G. Samygin
doaj   +1 more source

U-Pb geochronology of the Fort Augustus granite gneiss: constraints on the timing of Neoproterozoic and Palaeozoic tectonothermal events in the NW Highlands of Scotland [PDF]

, 2001
The West Highland granite gneiss suite in Inverness-shire, Scotland, represents a series of S-type, anatectic granites formed by partial melting of host Neoproterozoic metasediments of the Moine Supergroup.
Kinny, P.D., Strachan, R.A., P. D. KINNY, Strachan, RA, Paterson, BA, Friend, C.R.L., Paterson, B.A., Kinny, PD, Rogerson, G., C. R. L. FRIEND, Rogers, G, G. ROGERS, Friend, CRL, R. A. STRACHAN, B. A. PATERSON   +14 more
core   +1 more source

SOURCES OF LOWER PALEOZOIC SANDSTONES FROM THE NORA-SUKHOTINO TERRANE: RESULTS OF U-Th-Pb AND Lu-Hf ISOTOPE STUDIES OF THE DETRITAL ZIRCONS

Геодинамика и тектонофизика, 2022
This paper presents the results of comprehensive geological and geochemical studies of sandstones from the Belaya basin of the Amur fragment of the Nora-Sukhotino terrane of the northeastern flank of South Mongolia-Khingan orogenic belt, as well as the ...
Y. V. Smirnov
doaj   +1 more source

Sustained increases in atmospheric oxygen and marine productivity in the Neoproterozoic and Palaeozoic eras

Nature Geoscience
A geologically rapid Neoproterozoic oxygenation event is commonly linked to the appearance of marine animal groups in the fossil record. However, there is still debate about what evidence from the sedimentary geochemical record—if any—provides strong ...
R. Stockey, D. Cole, Una C. Farrell, Heda Agić, Thomas H. Boag, Jochen J. Brocks, Donald E. Canfield, Cheng Meng, P. Crockford, H. Cui, T.W. Dahl, Lucas Del Mouro, K. Dewing, Stephen Q. Dornbos, J. Emmings, Robert R. Gaines, T. Gibson, Benjamin C. Gill, G. Gilleaudeau, Karin Goldberg, R. Guilbaud, G. Halverson, Emma U. Hammarlund, Kalev G. Hantsoo, Miles A. Henderson, Charles M. Henderson, M. Hodgskiss, Amber J. M. Jarrett, David T. Johnston, P. Kabanov, Julien Kimmig, A. H. Knoll, M. Kunzmann, M. LeRoy, Chao Li, D. K. Loydell, F. A. Macdonald, J. Magnall, N. T. Mills, L. Och, Brennan O’Connell, Anais Pagès, Shanan E. Peters, S. Porter, S. Poulton, S. Ritzer, Alan D. Rooney, S. Schoepfer, Emily F. Smith, Justin V. Strauss, G. Uhlein, Tristan White, Rachel A. Wood, C. Woltz, I. Yurchenko, N. Planavsky, Erik A. Sperling   +56 more
semanticscholar   +1 more source

DETRITAL ZIRCONS FROM THE PRECAMBRIAN OF THE IGARKA UPLIFT (NORTHWESTERN SIBERIAN PLATFORM)

Геодинамика и тектонофизика
Herein we report the results of LA-ICP-MS dating of detrital zircons from eight stratigraphic levels of the Proterozoic section of the Igarka uplift (northwestern Siberian Platform).
B. B. Kochnev, D. V. Semenova, V. B. Khubanov, M. K. Danukalova, V. V. Marusin, A. K. Khudoley   +5 more
doaj   +1 more source

Fibrous dolomite formation at a Miocene methane seep may reflect Neoproterozoic aragonite-dolomite sea conditions

Communications Earth & Environment, 2023
Fibrous dolomite widely formed in Neoproterozoic marine sedimentary environments, but apparently disappeared in the Phanerozoic. Here, fibrous dolomite is recognised in a Miocene methane seep limestone (Marmorito, Italy) by synchrotron X-ray diffraction,
Yang Lu, Carsten Paulmann, Boriana Mihailova, Thomas Malcherek, Daniel Birgel, Matthias López Correa, Zhiyong Lin, Liuyi Lu, Yvonne Milker, Jörn Peckmann   +9 more
doaj   +1 more source