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 …

This review of material relevant to the Conference on Biosignature Preservation and
Detection in Mars Analog Environments summarizes the meeting materials and discussions …

Abstract The ca. 3.48 Ga Dresser Formation, Pilbara Craton, Western Australia, is well
known for hosting some of Earth's earliest convincing evidence of life (stromatolites …

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

Abstract The Mars rover Spirit encountered outcrops and regolith composed of opaline silica
(amorphous SiO2· n H2O) in an ancient volcanic hydrothermal setting in Gusev crater. An …

uring the spring of 1960, an uncle showed me a 'petrifying spring'near Plaxtol in Kent
Dwhere twigs had been encased in a calcareous jacket. A twig was collected and having …

Chert deposits preserve a record of secular change in the oceanic silica cycle. The
evolutionary radiation of silica-secreting organisms resulted in a transition from abiological …

Microbial life permeates Earth's critical zone and has likely inhabited nearly all our planet's
surface and near subsurface since before the beginning of the sedimentary rock record …

Abstract The Ediacara Biota, Earth's earliest fossilized ecosystem of complex, macroscopic,
multicellular organisms, occurs in terminal Ediacaran strata worldwide, yet how the fossils …

The recognition of past habitable environments on Mars has increased the urgency to
understand biosignature preservation in and characterize analogues of these environments …