Almost the entire seafloor is covered with sediments that can be more than 10 000 m thick
and represent a vast microbial ecosystem that is a major component of Earth's element and …

Earth has been habitable for 4.3 billion years, and the earliest rock record indicates the
presence of a microbial biosphere by at least 3.4 billion years ago—and disputably earlier …

Biological activity is a major factor in Earth's chemical cycles, including facilitating CO2
sequestration and providing climate feedbacks. Thus a key question in Earth's evolution is …

The ubiquity of Au-bearing arsenian pyrite in hydrothermal ore deposits suggests that the
coupled geochemical behaviour of Au and As in this sulfide occurs under a wide range of …

Emissions of methane, a potent greenhouse gas, from marine sediments are controlled by
anaerobic oxidation of methane coupled primarily to sulphate reduction (AOM). Sulphate …

Abstract The Archean era (4 to 2.5 billion years ago, Ga) yielded rocks that include the
oldest conclusive traces of life as well as many controversial occurrences. Carbonaceous …

The sulfur biogeochemical cycle integrates the metabolic activity of multiple microbial
pathways (eg, sulfate reduction, disproportionation, and sulfide oxidation) along with abiotic …

Construction and assembly of the Geologic Time Scale involves:(a) constructing a relative
(chronostratigraphic) standard scale for key periods in the Earth's rock record;(b) identifying …

Uncovers the Key Role Microbes Play in the Transformation of Oxidizable and Reducible
MineralsMany areas of geomicrobial processes are receiving serious attention from …

Dissimilatory sulphate reduction is the unifying and defining trait of sulphate-reducing
prokaryotes (SRP). In their predominant habitats, sulphate-rich marine sediments, SRP have …