Uncovering the Neoproterozoic carbon cycle [PDF]
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
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 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]
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]
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]
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]
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]
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]
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]
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

