Recently in the Astrogeology Category


The magma ocean period was a critical phase determining how Earth atmosphere developed into habitability.

Chondrites, the building blocks of the terrestrial planets, have mass and atomic proportions of oxygen, iron, magnesium, and silicon totaling ≥90% and variable Mg/Si (∼25%), Fe/Si (factor of ≥2), and Fe/O (factor of ≥3).

The atmospheres of temperate planets may be regulated by geochemical cycles. Silicate weathering provides essential negative feedback to the carbonate-silicate cycle (carbon cycle) to maintain temperate climates on Earth and possibly on Earth-sized temperate exoplanets.

Hydrogen in rocky planet atmospheres has been invoked in arguments for extending the habitable zone via N2-H2 and CO2-H2 greenhouse warming, and providing atmospheric conditions suitable for efficient production of prebiotic molecules.

The diversity in mass and composition of planetary atmospheres stems from the different building blocks present in protoplanetary discs and from the different physical and chemical processes that these experience during the planetary assembly and evolution.

Subduction of hydrous materials imposes great influence on the structure, dynamics, and evolution of our planet. However, it is largely unclear how subducting slabs chemically interact with the middle mantle.

Carbon is an essential building block for all living things on Earth and plays a vital role in many of the geologic processes that shape life on the planet, including climate change and ocean acidification. But the total amount of carbon on Earth remains a mystery, because more than 90% of Earth's carbon is inaccessible to direct observation and measurement, deep within the planet at extreme temperature and pressure.

New research lends credence to an unorthodox retelling of the story of early Earth first proposed by a geophysicist at Scripps Institution of Oceanography at UC San Diego.

Spearheaded by earth scientists of the University of Cologne, an international team of geologists has found evidence that a large proportion of the elements that are important for the formation of oceans and life, such as water, carbon and nitrogen, were delivered to Earth very late in its history.

Flash Floods In The Mid-Archean

Scientists supported in part by the NASA Astrobiology Program have provided new details of how the Hooggeneoeg Formation in South Africa was formed. The Hooggeneoeg Formation is found in the Barberton Greenstone Belt, and holds some of the best-preserved examples of supracrustal rocks from the mid-Archean (3.5 to 3.2 billion years ago).