Hadean Earth

  title={Hadean Earth},
  author={T. Mark Harrison},
  journal={Hadean Earth},
The development of the geologic timescale arose from early nineteenth century fossil correlations and thus firmly rooted in the rock record. The thinking of that time included the possibility that our planet had forever existed in a quasi-steady state. By the later part of that century, it was broadly understood that Earth must have experienced a discrete origin but that details of that event might never be discerned. The advent of radiometric dating shortly thereafter catapulted this… 

Hadean geodynamics and the nature of early continental crust

Eoarchean and Hadean melts reveal arc-like trace element and isotopic signatures

Constraining the lithological diversity and tectonics of the earliest Earth is critical to understanding our planet’s evolution. Here we use detrital Jack Hills zircon (3.7 − 4.2 Ga) analyses coupled

Plate tectonics in the twenty-first century

Plate tectonics was originally established as a kinematic theory of global tectonics, in which the Earth’s rigid outer layer, the lithosphere, consists of different size plates that move relative to

Oxygen isotope (δ18O, Δ′17O) insights into continental mantle evolution since the Archean

Oxygen isotopic ratios are largely homogenous in the bulk of Earth’s mantle but are strongly fractionated near the Earth’s surface, thus these are robust indicators of recycling of surface materials

Constraining prebiotic chemistry through a better understanding of Earth’s earliest environments

Any search for present or past life beyond Earth should consider the initial processes and related environmental controls that might have led to its start. As on Earth, such an understanding lies

Recognition of Sedimentary Rock Occurrences in Satellite and Aerial Images of Other Worlds - Insights from Mars

Global coverage at 0.25–6 m/pixel, and observations from the Curiosity rover in Gale crater, expand the ability to recognize Martian sedimentary rocks, and it is likely that Mars likely has much more sedimentary rock than previously recognized.

A record of ancient cataclysm in modern sand: Shock microstructures in detrital minerals from the Vaal River, Vredefort Dome, South Africa

The record of terrestrial meteorite impacts is fragmentary because most impact structures and ejecta are removed by erosion or buried. Discovery of the missing impact record from Hadean to present

The Habitability of Venus

Venus today is inhospitable at the surface, its average temperature of 750 K being incompatible to the existence of life as we know it. However, the potential for past surface habitability and upper

A Bayesian Analysis of Technological Intelligence in Land and Oceans

Current research indicates that (sub)surface ocean worlds essentially devoid of subaerial landmasses (e.g., continents) are common in the Milky Way and that these worlds could host habitable

Perseverance’s Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) Investigation

The Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) is a robotic arm-mounted instrument on NASA’s Perseverance rover. SHERLOC has two primary



The beginning of continental evolution

Emergence of a Habitable Planet

Abstract We address the first several hundred million years of Earth’s history. The Moon-forming impact left Earth enveloped in a hot silicate atmosphere that cooled and condensed over ∼1,000 yrs. As

The persistent myth of crustal growth

From the extraterrestrial telescopic, space probe, meteorite and returned sample studies of planetary evolution, and terrestrial evidence for early differentiation of core and fluid spheres and

Zircon Thermometer Reveals Minimum Melting Conditions on Earliest Earth

The temperatures substantiate the existence of wet, minimum-melting conditions within 200 million years of solar system formation and suggest that Earth had settled into a pattern of crust formation, erosion, and sediment recycling as early as 4.35 Ga.

The first 800 million years of Earth's history

  • J. V. Smith
  • Geology
    Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences
  • 1981
The Earth grew initially from hot planetesimals of reduced material, and began to differentiate early into a metal-rich core, a silicate-rich mantle and a volcanic surface. Accretion ended with

A cool early Earth?

The hypothesis of a cool early Earth suggests long intervals of relatively temperate surface conditions from 4.4 to 4.0 Ga that were conducive to liquidwater oceans and possibly life and may have been less frequent than previously thought.

Origin of the cataclysmic Late Heavy Bombardment period of the terrestrial planets

This model not only naturally explains the Late Heavy Bombardment, but also reproduces the observational constraints of the outer Solar System.

The major differentiation of the Earth at ∼ 4.45 Ga