geochronology Archives - Astrobiology

Photographs of Tava injectites within a darker-colored, red-brown to purple host comprising sandstone ridges. Outcrops (A) and (C) and their sketch overlays (B) and (D), respectively, showing 1st-(purple) and 2nd-(gold) generation injectites. Locations are North Cheyenne Canyon (A, B) and Manitou Springs (C, D). (A-B) are repeated from the main text figures but display further highlighted details. Study locations are shown in Fig. S2. -- PNAS

Astrogeology, Atmospheres, Climate, Weather, Away Teams & Field Reports, Biogeochemical Cycles & Geobiology, Cryobiology, Extinction events, Habitable Zones, Icy Worlds, Mapping, Geodesy, Cartography, Bathymetry, Status Report, Water/Hycean Worlds & Oceanography

Hematite U-Pb Dating Of Snowball Earth Meltwater Events

by Keith CowingDecember 2, 2024December 2, 2024

The Snowball Earth hypothesis predicts global ice cover; however, previous descriptions of Cryogenian (720-635 Ma) glacial deposits are limited to continental margins and shallow marine basins.

The Lafayette Meteorite -- Purdue University

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Habitable Zones, Impact events, Mars, Meteorites & Asteroids, Press Release

Meteorite Contains Evidence Of Liquid Water On Mars 742 Million Years Ago

by Keith CowingNovember 24, 2024November 24, 2024

An asteroid struck Mars 11 million years ago and sent pieces of the red planet hurtling through space. One of these chunks of Mars eventually crashed into the Earth somewhere […]

A dolomite sample from the Cambrian Muav formation as seen through a microscope. Multiple generations of mineral-growth can be seen. In the study we used a laser-ablation system to sample specific mineral fabrics and measure their U- and Pb compositions. -- Uri Ryb

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Fossils & Paleontology, Gaia - Planetary Perspectives, Mapping, Geodesy, Cartography, Bathymetry, Origin & Evolution of Life, Press Release, Water/Hycean Worlds & Oceanography

Ancient Earth’s Ocean Oxygenation Timeline Revealed

by Keith CowingApril 5, 2024April 5, 2024

New study introduces a pioneering application of dolomite U-Pb geochronology, shedding new light on the evolution of ancient marine environments. By uncovering discrepancies in dolomite samples U-Pb ratios, the team […]

The Latest Permian Mass Extinction (LPME)

Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Extinction events, Press Release

Mercury Helps to Detail Earth’s Most Massive Extinction Event

by Keith CowingJanuary 28, 2023

The Latest Permian Mass Extinction (LPME) was the largest extinction in Earth’s history to date, killing between 80-90% of life on the planet, though finding definitive evidence for what caused […]