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Uncovering the Neoproterozoic carbon cycle [PDF]

open access: yesNature, 2012
Interpretations of major climatic and biological events in Earth history are, in large part, derived from the stable carbon isotope records of carbonate rocks and sedimentary organic matter. Neoproterozoic carbonate records contain unusual and large negative isotopic anomalies within long periods (10-100 million years) characterized by δ(13)C in ...
Johnston, David   +4 more
openaire   +3 more sources

Neoproterozoic Earth-life system

open access: yesPrecambrian Research, 2022
Abstract The Earth-life system witnessed dramatic changes over the Neoproterozoic (1000–541 Ma). It saw supercontinent reconfigurations from the breakup of Rodinia to the assembly of Gondwana; climatically, the deepest global freeze in Earth history; geochemically, some of the most extreme perturbations on record; and biologically, the prominent rise
Qing Tang, Huan Cui, Feifei Zhang
openaire   +1 more source

The Neoproterozoic [PDF]

open access: yesCurrent Biology, 2015
The Neoproterozoic era was arguably the most revolutionary in Earth history. Extending from 1000 to 541 million years ago, it stands at the intersection of the two great tracts of evolutionary time: on the one side, some three billion years of pervasively microbial 'Precambrian' life, and on the other the modern 'Phanerozoic' biosphere with its ...
openaire   +2 more sources

Chemostratigraphy of Neoproterozoic carbonates: implications for 'blind dating' [PDF]

open access: yes, 2001
The delta C-13(carb) and Sr-87/Sr-86 secular variations in Neoproteozoic seawater have been used for the purpose of 'isotope stratigraphy' but there are a number of problems that can preclude its routine use.
Aharon P.   +55 more
core   +1 more source

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

open access: yes, 1998
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   +16 more
core   +4 more sources

Paradigm shift in determining Neoproterozoic atmospheric oxygen [PDF]

open access: yes, 2016
ACKNOWLEDGMENTS We thank the Geological Survey of Australia for permission to sample the Empress 1A and Lancer 1 cores, the Natural Sciences and Engineering Research Council of Canada for financial support (grant #7961–15) of U.
Benison, Kathleen   +7 more
core   +3 more sources

Tellurium, selenium and cobalt enrichment in Neoproterozoic black shales, Gwna Group, UK : Deep marine trace element enrichment during the Second Great Oxygenation Event [PDF]

open access: yes, 2018
We are grateful to John Still for his skilled technical support and the ACEMAC facility at the University of Aberdeen. Research funded by NERC grant NE/M010953/1 and NERC facility grant IP-1631-0516. AJB is funded by NERC support of the Isotope Community
Armstrong, Joseph   +5 more
core   +2 more sources

87Sr/86Sr chemostratigraphy of Neoproterozoic Dalradian limestones of Scotland and Ireland: constraints on depositional ages and time scales [PDF]

open access: yes, 2004
New calcite <sup>87</sup>Sr/<sup>86</sup>Sr data for 47 limestones from the metamorphosed and deformed Neoproterozoic-Cambrian Dalradian Supergroup of Scotland and Ireland are used to identify secular trends in seawater <sup>
Ellam, R.M.   +3 more
core   +1 more source

Dynamics of the Neoproterozoic carbon cycle [PDF]

open access: yesProceedings of the National Academy of Sciences, 2003
The existence of unusually large fluctuations in the Neoproterozoic (1,000–543 million years ago) carbon-isotopic record implies strong perturbations to the Earth's carbon cycle. To analyze these fluctuations, we examine records of both the isotopic content of carbonate carbon and the fractionation between carbonate and marine organic carbon ...
Daniel H, Rothman   +2 more
openaire   +2 more sources

A secular increase in continental crust nitrogen during the Precambrian [PDF]

open access: yes, 2017
Recent work indicates the presence of substantial geologic nitrogen reservoirs in the mantle and continental crust. Importantly, this geologic nitrogen has exchanged between the atmosphere and the solid Earth over time. Changes in atmospheric nitrogen (i.
Goldblatt, Colin, Johnson, Benjamin W
core   +3 more sources

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