Widespread mixing and burial of Earth’s Hadean crust by asteroid impacts

  title={Widespread mixing and burial of Earth’s Hadean crust by asteroid impacts},
  author={Simone Marchi and William F. Bottke and Linda T. Elkins‐Tanton and M. Bierhaus and K. Wuennemann and Alessandro Morbidelli and David A. Kring},
The history of the Hadean Earth (∼4.0–4.5 billion years ago) is poorly understood because few known rocks are older than ∼3.8 billion years old. The main constraints from this era come from ancient submillimetre zircon grains. Some of these zircons date back to ∼4.4 billion years ago when the Moon, and presumably the Earth, was being pummelled by an enormous flux of extraterrestrial bodies. The magnitude and exact timing of these early terrestrial impacts, and their effects on crustal growth… 
Potassic, high-silica Hadean crust
Analysis of strontium isotopic composition of apatite inclusions in zircons from Nuvvuagittuq, Canada, shows that its protolith had formed a high Rb/Sr ratio reservoir by at least 4.2 Ga, which implies that the early crust had a broad range of igneous rocks, extending from mafic to highly silicic compositions.
Decline of giant impacts on Mars by 4.48 billion years ago and an early opportunity for habitability
The timing of the wane in heavy meteorite bombardment of the inner planets is debated. Its timing determines the onset of crustal conditions consistently below the thermal and shock pressure limits
Formation of Hadean granites by melting of igneous crust
The oldest known samples of Earth, with ages of up to 4.4 Gyr, are detrital zircon grains in meta-sedimentary rocks of the Jack Hills in Australia. These zircons offer insights into the magmas from
The Archean atmosphere
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Evolution of Early Atmosphere
Earth’s early surface environment had great influence on the origin of life through formation of its building blocks. From geological and geochemical evidence, the Earth’s atmosphere and oceans
Probable Cold and Alkaline Surface Environment of the Hadean Earth Caused by Impact Ejecta Weathering
Constraining the surface environment of the early Earth is essential for understanding the origin and evolution of life. The release of cations from silicate weathering depends on climatic
Geoastronomy: Rocky planets as the Lavosier-Lomonosov Bridge from the non-living to the living world
WEB SUMMARY Life on Earth emerged at the interface of the planet’s geosphere, hydrosphere and atmosphere. This setting serves as our basis for how biological systems originate on rocky planets. Often


Evidence from detrital zircons for the existence of continental crust and oceans on the Earth 4.4 Gyr ago
The discovery of a detrital zircon with an age as old as 4,404 ± 8 Myr is reported, about 130 million years older than any previously identified on Earth and represents the earliest evidence for continental crust and oceans on the Earth.
The Hadean Crust: Evidence from >4 Ga Zircons
A review of continental growth models leaves open the possibilities that Earth during the Hadean Eon (∼4.5–4.0 Ga) was characterized by massive early crust or essentially none at all. Without support
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
Oxygen-isotope evidence from ancient zircons for liquid water at the Earth's surface 4,300 Myr ago
In situ U–Pb and oxygen isotope results for detrital zircons found within 3-Gyr-old quartzitic rocks in the Murchison District of Western Australia are consistent with the presence of a hydrosphere interacting with the crust by 4,300 Myr ago and are postulated to form from magmas containing a significant component of re-worked continental crust.
The Hadean-Archaean environment.
  • N. Sleep
  • Geology
    Cold Spring Harbor perspectives in biology
  • 2010
Overall, mantle derived rocks, especially kimberlites and similar CO(2)-rich magmas, preserve evidence of subducted upper oceanic crust, ancient surface environments, and biosignatures of photosynthesis.
Processes on the Young Earth and the Habitats of Early Life
Conditions at the surface of the young (Hadean and early Archean) Earth were suitable for the emergence and evolution of life. After an initial hot period, surface temperatures in the late Hadean may
The oldest rocks on Earth: time constraints and geological controversies
Abstract Ages in the range 3.6–4.0 Ga (billion years) have been reported for the oldest, continental, granitoid orthogeneisses, whose magmatic precursors were probably formed by partial melting or
Mass flux in the ancient Earth‐Moon system and benign implications for the origin of life on Earth
The origin of life on Earth is commonly considered to have been negatively affected by intense impacting in the Hadean, with the potential for the repeated evaporation and sterilization of any ocean.
Impact melt sheet zircons and their implications for the Hadean crust
Impacts may have been important mechanisms of crustal redistribution and differentiation, particularly during intense postaccretionary bombardment between 4.5 Ga and 3.9 Ga ago. Evidence of crustal