Snowballs in Africa: sectioning a long-lived Neoproterozoic carbonate platform and its bathyal foreslope (NW Namibia)

PF Hoffman, GP Halverson, DP Schrag, JA Higgins… - Earth-Science …, 2021 - Elsevier
Abstract Otavi Group is a 1.5–3.5-km-thick epicontinental marine carbonate succession of
Neoproterozoic age, exposed in an 800-km-long Ediacaran− Cambrian fold belt that rims …

Biogeochemical cycle of chromium isotopes at the modern Earth's surface and its applications as a paleo-environment proxy

W Wei, R Klaebe, HF Ling, F Huang, R Frei - Chemical Geology, 2020 - Elsevier
Chromium (Cr) is a redox-sensitive metal element with two natural oxidation states,
commonly as the soluble Cr (VI) oxyanion (CrO 4 2− or HCrO 4−) and the insoluble Cr (III) …

Biological diversification linked to environmental stabilization following the Sturtian Snowball glaciation

FT Bowyer, AJ Krause, Y Song, KJ Huang, Y Fu… - Science …, 2023 - science.org
The body fossil and biomarker records hint at an increase in biotic complexity between the
two Cryogenian Snowball Earth episodes (ca. 661 million to≤ 650 million years ago) …

Oxygenation variations in the atmosphere and shallow seawaters of the Yangtze Platform during the Ediacaran Period: Clues from Cr-isotope and Ce-anomaly in …

W Wei, R Frei, GJ Gilleaudeau, D Li, GY Wei… - Precambrian …, 2018 - Elsevier
Abstract The late Neoproterozoic Era witnessed a significant oxygenation in Earth's surface
in line with the naissance and diversity of early animals; however, detailed variations of the …

Multiproxy geochemical and isotope stratigraphy records of a Neoproterozoic Oxygenation Event in the Ediacaran Sete Lagoas cap carbonate, Bambuí Group, Brazil

FA Caxito, R Frei, GJ Uhlein, TG Dias, TB Árting… - Chemical …, 2018 - Elsevier
In order to investigate the geochemical responses of Earth's oceans and atmosphere after a
Snowball glaciation, we studied an Ediacaran cap carbonate profile pertaining to the base of …

[HTML][HTML] Sabkha and salina dolomite preserves the biogeochemical conditions of its depositional paleoenvironment

M Sánchez-Román, L Gibert, JD Martín-Martín… - … et Cosmochimica Acta, 2023 - Elsevier
Precipitation of Mg-carbonate minerals, ranging from Mg-calcite to Ca-rich dolomite, is
typically associated with microbial activity, and commonly takes place in saline …

Geochronological constraints on Cryogenian ice ages: Zircon UPb ages from a shelf section in South China

X Ma, J Wang, Z Wang, TJ Algeo, C Chen… - Global and Planetary …, 2023 - Elsevier
Abstract Radiometric dating of Neoproterozoic Cryogenian glacial deposits is critical for
constraining the duration of the Sturtian and Marinoan ice ages and understanding the …

Chromium isotope cycling in the water column and sediments of the Peruvian continental margin

S Bruggmann, F Scholz, RM Klaebe… - … et Cosmochimica Acta, 2019 - Elsevier
Chromium (Cr) isotope fractionation is sensitive to redox changes and the Cr isotopic
composition (δ 53 Cr) of sedimentary rocks has been used to reconstruct marine redox …

The role of pH on Cr (VI) partitioning and isotopic fractionation during its incorporation in calcite

A Füger, S Bruggmann, R Frei, A Leis, M Dietzel… - … et Cosmochimica Acta, 2019 - Elsevier
The Cr (VI) incorporation and chromium stable isotope composition in calcite has been
studied in experiments performed in the pH range between 8.0 and 10.6 at constant …

Redox heterogeneity of the Ediacaran ocean constrained by chromium isotopes

X He, Z Fang, Y Gao, X Yu, Y Shen, L Qin - Geochimica et Cosmochimica …, 2023 - Elsevier
Ocean oxygenation during the Ediacaran Period (635–541 Ma) is thought to be a potential
stimulus for the emergence and diversification of early animals. However, the atmospheric …