Earth and Planetary Sciences ETDs

Publication Date

Summer 7-28-2026

Abstract

Two leading models of planet formation invoke either stochastic collisions among km-sized planetesimals, or pebble accretion of sub-mm-cm solids regulated by gas drag. While collision based models typically require tens to hundreds of millions of years to assemble terrestrial planets, pebble accretion can produce Mars to Jupiter-mass bodies within the lifetime of the protoplanetary disk. Although widely accepted for the rapid growth of giant planet cores, the role of pebble accretion in forming terrestrial planets, including Earth, remains debated. Here, we investigate the consequences of pebble accretion for Earth’s origin. Here, I combine numerical models and laboratory experiments to find the potential building blocks for terrestrial planets from known meteoritic materials. I explored what source material(s) 1) reproduce Earth’s composition, 2) deliver water, and 3) reproduce compositions of Venus, Mars, and Mercury. Collectively, I found that pebble accretion of chondritic components may have been a common mechanism for our terrestrial planets.

Degree Name

Earth and Planetary Sciences

Level of Degree

Doctoral

Department Name

Department of Earth and Planetary Sciences

First Committee Member (Chair)

Zachary Sharp

Second Committee Member

Peter Olson

Third Committee Member

Kara Brugman

Fourth Committee Member

Jin Zhang

Fifth Committee Member

Wladimir Lyra

Keywords

Pebble accretion, major element composition, water on Earth, terrestrial planets.

Document Type

Dissertation

Comments

This is a revised version in response to the suggested edits. 

Download

Share

COinS