Hadean Eon

References: Hazen, Robert M., and Shaunna M. Morrison. “Mineralogical Environments of the Hadean Eon: Rare Elements Were Ubiquitous in Surface Sites of Rock-Forming Minerals: Rare Elements Ubiquitous on Rock-Forming Mineral Surfaces in the Hadean.” Prebiotic Chemistry and the Origin of Life. Cham: Springer International Publishing, 2022. 43–61. Web. Thomassot, Emilie et al. “Atmospheric Record in the Hadean Eon from Multiple Sulfur Isotope Measurements in Nuvvuagittuq Greenstone Belt (Nunavik, Quebec).” Proceedings of the National Academy of Sciences - PNAS 112.3 (2015): 707–712. Web. John P. Rafferty. “Hadean Eon.” Encyclopædia Britannica Online 2020: n. pag. Print.

The temperature on the surface ranged from 230 to 500 degrees centigrade. Atmospheric pressure could have topped 27 times modern levels. Despite the destructive hellscape, the first evidence of life has been found in Hadean Eon rocks dated 4100 Mya.

mostly composed of CO2 from the constant evolution of volcanism and impact events.

Earth was the appearance of silica-rich igneous rocks, collectively called granite. One of the hallmarks of the Hadean Eon was the development of raft-like provinces of granite that could 'float' above the heavier basaltic ocean magmas. The atmosphere was

Facts about the Hadean Eon: The Hadean Eon was a hellish world, steeped in continuous episodes of surface melting capped in a toxic, tenuous atmosphere. The impact that formed the moon took place during this eon, which nearly blew apart the Earth entirely. A critical mineralogical innovation on

The lunar tides during the Hadean Eon were extreme due to the 84 hour orbit of the moon.

Lunar Tides

Evidence of the first planet-spanning oceans have been found in the earliet rocks on Earth. These oceans were the environments where the first life is expected to have arisen.

The First Oceans

During this eon, the Earth's layers began separating into the distinct layers that we see today

Evidence of multiple asteroids measuring 60 miles wide or more rained down on Earth during this time period.

The early Hadean eon may have had a periodically ice-covered global ocean and limited subaerial landmass, and this could have resulted in infrequent lightning occurrence. These conditions are reportedly the same conditions laboratory experiments have confirmed produce the building blocks of primordial life.

Explanations of Early Life

Asteroid Impacts

Planetary Differentiation

4567.3 – 4000 Mya

Hadean Eon

Explanations of Early Life

The first signs of what is known as biogenic carbon appeared in the rocks of this tumultuous era, which is the proportional preference of Carbon-12 over Carbon-13. This suggests that life gained a foothold even in the ealiest stages of Earth's history.

First Oceans

Evidence exists that suggests that very soon after the moon forming impact, the Earth was covered in oceans more that deep enough to support and aid in the formation of deep ocean hydrothermal vents. These were some of the first environments that life is suggested to have colonized, and may have played a role in their development as well.

Planetary Differentiation

The constant bombardment of iron and nickel rich rock led to the melting and differentiation of the various metals comprising the Earth. This caused the formation of the various layers that exist today on our planet.

Asteroid Impacts

During this eon the Earth was frequently lit up by the blazing devastation attributed to the impacts similar to the one that wiped out the dinosaurs! Temperatures soared and weren't allowed to fall for many millions of year.

Lunar Tides

During this eon, Earth was constantly rocked by raging tides that carried with them tidal bores on the scale of 100s of meters. This caused a churning of the nutrient-rich deep waters with the surface that likely created the perfect environment for the development of life.