The geological record preserves evidence for two fundamental stages in the evolution of Earth's biosphere, a microbial stage from~ 3.5 to 0.65 Ga, and a metazoan stage evident by …
Sedimentary pyrite formed in the water column, or during diagenesis in organic muds, provides an accessible proxy for seawater chemistry in the marine rock record. Except for …
JD Rummel, DW Beaty, MA Jones, C Bakermans… - 2014 - liebertpub.com
A committee of the Mars Exploration Program Analysis Group (MEPAG) has reviewed and updated the description of Special Regions on Mars as places where terrestrial organisms …
Abstract The Glen Torridon (GT) region in Gale crater, Mars is a region with strong clay mineral signatures inferred from orbital spectroscopy. The CheMin X‐ray diffraction (XRD) …
PK Pufahl, LA Groat - Economic Geology, 2017 - pubs.geoscienceworld.org
Phosphorus is the central ingredient in fertilizer that allows modern agriculture to feed the world's population. This element, also critical in a host of industrial applications, is a …
Persistent anoxia and the lack of a skeletal silica sink through the Precambrian would have promoted a variety of reactions between iron and dissolved silica through much of Earth's …
JE Johnson, SM Webb, K Thomas… - Proceedings of the …, 2013 - National Acad Sciences
The emergence of oxygen-producing (oxygenic) photosynthesis fundamentally transformed our planet; however, the processes that led to the evolution of biological water splitting have …
The BIF-hosted iron ore system represents the world's largest and highest grade iron ore districts and deposits. BIF, the precursor to low-and high-grade BIF hosted iron ore, consists …
AH Knoll, KD Bergmann… - … Transactions of the …, 2016 - royalsocietypublishing.org
Microfossils, stromatolites, preserved lipids and biologically informative isotopic ratios provide a substantial record of bacterial diversity and biogeochemical cycles in Proterozoic …