Calcite Crystals and Earth’s Microbial History
January 05, 2022
Photographer: Henrik Drake
Summary Author: Henrik Drake
This photo shows calcite crystals taken from a deep fracture in Swedish granite that were used to study Earth's mineralogy and microorganism history. These kinds of mineral related biosignatures were used as part of a new study to look for ancient habitable conditions at deep depths. The recent article published in the PNAS Journal in November 2021 was the first study of Earth’s mineral and microbiology history from a thermochronological perspective. The study describes Earth’s Precambrian cratons and how habitability has persisted for not much longer than the past 1 billion years.