The terminal Neoproterozoic Era (850-542 Ma) is characterized by the most pronounced positive sulfur isotope ((34)S/(32)S) excursions in Earth's history, with strong variability and maximum values averaging δ(34)S∼+38‰. These excursions have been mostly interpreted in the framework of steady-state models, in which ocean sulfate concentrations do not fluctuate (that is, sulfate input equals sulf...

Epifaunal tiering, the subdivision of vertical space within a community, is a fundamental attribute of Phanerozoic suspension-feeding communities. This paper documents tiering, including the presence of meter-tall organisms, in Neoproterozoic Ediacaran communities. Ediacaran tiering was studied from three exceptionally preserved deep-water communities at Mistaken Point, Newfoundland, which cont...

Between ;750 and 635 million years ago, during the Neoproterozoic era, the earth experienced at least two significant, possibly global, glaciations, termed ‘‘Snowball Earth.’’ While many studies have focused on the dynamics and the role of the atmosphere and ice flow over the ocean in these events, only a few have investigated the related associated ocean circulation, and no study has examined ...

The glaciations of the Neoproterozoic Era (1,000 to 542 MyBP) were preceded by dramatically light C isotopic excursions preserved in preglacial deposits. Standard explanations of these excursions involve remineralization of isotopically light organic matter and imply strong enhancement of atmospheric CO(2) greenhouse gas concentration, apparently inconsistent with the glaciations that followed....

Investigation of climatic conditions prior to the Sturtian glaciations is critical to understanding the trigger mechanism for the series of Neoproterozoic global glaciations. In this study, we report high-resolution chemical index of alteration (CIA) records in the sediments of South China prior to the Sturtian glaciation (820~720 Ma). Our results showed there occurred multiple climate cooling ...

During the latest Neoproterozoic to Mid-Cambrian time (580–505 Ma ago), the Earth underwent significant changes in palaeogeography that included rifting of a possible supercontinent and the near simultaneous formation of a second, slightly smaller supercontinent. It is against this tectonic backdrop that the Cambrian radiation occurred. Although the general tectonic setting during this interval...