Astrogeology

Geophysical Evolution During Rocky Planet Formation

By Keith Cowing
astro-ph.EP
March 22, 2022
Filed under
Geophysical Evolution During Rocky Planet Formation
Chronology of geophysical and geochemical processes that affect the interior dynamics, structure, and climate of rocky planets. Planet size is normalized to current growth stage, starting from accretion in the disk (planetesimal stage), post-disk (giant impact phase), planet solidification and atmosphere formation (magma ocean crystallization), to the long-term evolution of interior and climate (secular geodynamic evolution). Processes schematically depicted here are introduced in §2, and discussed in the context of accretion in §3.

Progressive astronomical characterization of planet-forming disks and rocky exoplanets highlight the need for increasing interdisciplinary efforts to understand the birth and life cycle of terrestrial worlds in a unified picture.

Here, we review major geophysical and geochemical processes that shape the evolution of rocky planets and their precursor planetesimals during planetary formation and early evolution, and how these map onto the astrophysical timeline and varying accretion environments of planetary growth. The evolution of the coupled core-mantle-atmosphere system of growing protoplanets diverges in thermal, compositional, and structural states to first order, and ultimately shapes key planetary characteristics that can discern planets harboring clement surface conditions from those that do not.

Astronomical campaigns seeking to investigate rocky exoplanets will require significant advances in laboratory characterization of planetary materials and time- and spatially-resolved theoretical models of planetary evolution, to extend planetary science beyond the Solar System and constrain the origins and frequency of habitable worlds like our own.

Tim Lichtenberg, Laura K. Schaefer, Miki Nakajima, Rebecca A. Fischer
Comments: 37 pages, 10 figures; under review for publication as a chapter in Protostars and Planets VII, University of Arizona Press; comments welcome; figures available at this https URL
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR); Atmospheric and Oceanic Physics (physics.ao-ph); Geophysics (physics.geo-ph)
Cite as: arXiv:2203.10023 [astro-ph.EP] (or arXiv:2203.10023v1 [astro-ph.EP] for this version)
Submission history
From: Tim Lichtenberg
[v1] Fri, 18 Mar 2022 15:41:51 UTC (7,547 KB)
https://arxiv.org/abs/2203.10023
Astrobiology,

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