chert Archives

Giant Meteorite Impact -- Grok via Astrobiology.com

Astrogeology, Atmospheres, Climate, Weather, Away Teams & Field Reports, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Extinction events, Fossils & Paleontology, Habitable Zones, Impact events, Mapping, Geodesy, Cartography, Bathymetry, Meteorites & Asteroids, Status Report

Effect Of A Giant Meteorite Impact On Paleoarchean Surface Environments And Life

by Keith CowingOctober 30, 2024October 30, 2024

Large meteorite impacts must have strongly affected the habitability of the early Earth. Rocks of the Archean Eon record at least 16 major impact events, involving bolides larger than 10 […]

Optical and electron microscope images of jaspilite from Dresser Formation (UWA100624). (A) Hand specimen of jaspilite from section J. (B) PPL image of jaspilite showing splotchy chert defined by heterogeneous distribution of minute Fe-rich particles. (C and D) PPL images showing location of FIB pit from jaspilitic chert. (E) Backscattered electron image of jaspilitic chert showing abundant minute particles, including platy laths (gre). (F and G) STEM-EDS iron and calcium element maps from FIB foil of jaspilitic chert showing minute crystals of greenalite (gre), siderite (sid), and apatite (ap) in chert cement (qtz). -- Science Advances

Astrogeology, Away Teams & Field Reports, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Extremeophiles and Extreme Environments, Fossils & Paleontology, Imaging & Spectroscopy, Microbiology & Virology, Status Report

Nanoparticulate Apatite and Greenalite In The Oldest, Well-preserved Hydrothermal Vent Precipitates

by Keith CowingJune 25, 2024June 25, 2024

Paleoarchean jaspilites are used to track ancient ocean chemistry and photoautotrophy because they contain hematite interpreted to have formed following biological oxidation of vent-derived Fe(II) and seawater P-scavenging.

chert

Effect Of A Giant Meteorite Impact On Paleoarchean Surface Environments And Life

Nanoparticulate Apatite and Greenalite In The Oldest, Well-preserved Hydrothermal Vent Precipitates

ALMA Central Molecular Zone Exploration Survey (ACES) I: Overview

RNA And Proteins Joined Up At The Origins Of Life: Persistence Is The Point

Selection For Growth Drives The Emergence Of Genetic Heredity In Protocells

NASA SMD ROSES-25 Amendment 65: New Opportunity: C.4 Planetary Science Enabling Facilities

TESS Photometry and Radial Velocity Analysis of the sub-Neptune Exoplanet π Mensae c and the Wider π Mensae Planetary System