The concentration of manganese in solution and its precipitation in inorganic systems are
primarily redox-controlled, guided by several Earth processes most of which were …

The Palaeoproterozoic positive excursion of δ 13C carb is now considered as three positive
shifts of δ 13C carb separated by returns to 0‰, which all occurred between 2.40 and 2.06 …

Cyanobacteria are among the most ancient of evolutionary lineages, oxygenic
photosynthesizers that may have originated before 3.0 Ga, as evidenced by free oxygen …

New data for the isotopic composition of carbon in carbonate sediments deposited between
2.6 and 1.6 Ga indicate that the value of δ13C in these sediments underwent a very large …

The response of the ocean redox state to the rise of atmospheric oxygen about 2.3 billion
years ago (Ga) is a matter of controversy. Here we provide iron isotope evidence that the …

The evidence for macroscopic life during the Palaeoproterozoic era (2.5–1.6 Gyr ago) is
controversial,,,,. Except for the nearly 2-Gyr–old coil-shaped fossil Grypania spiralis,, which …

A map**, tectonic (deformation, kinematics), petrologic (P–T paths) and geochronological
approach has enabled us to define the Paleoproterozoic West Central African Belt (WCAB) …

The oxygen content of Earth's atmosphere has varied greatly through time, progressing from
exceptionally low levels before about 2.3 billion years ago, to much higher levels afterward …

Natural nuclear fission reactors are only known in two uranium deposits in the world, the
Oklo and Bangombé deposits of the Franceville basin: Gabon. Since 1982, five new reactor …

Abstract The Lower Cambrian black shale sequence of the Niutitang Formation in the
Yangtze Platform, South China, hosts an extreme metal-enriched sulfide ore bed that …