Degree
Doctor of Philosophy (PhD)
Department
Geology and Geophysics
Document Type
Dissertation
Abstract
The continued study of our solar system has led to an advent of new industries and technologies. Mars in particular, is of great interest as it is one of our closest stellar neighbors and bears remarkable similarity to a ‘proto-Earth.’ Detailed studies of the red planet involve a combination of techniques, ranging from satellite remote sensing to in-situ observations from rovers. The difference in scale between these two modes of investigation creates a disparity in scientific literature, where regional to global observations at times conflict with local observations. Thus, optimizing our remote sensing techniques and advancing our understanding of them is of great importance. The chapters of this work use a variety of data from remote sensing sources, ranging from geochemical to geophysical, in an effort to explain the complex geologic history of Mars.
In chapter 1, geochemical data derived from Gamma-ray spectroscopy in combination with geophysical data derived from admittance modeling are used to uncover the unique provenance of the Arabia Terra region on Mars. This region may have been host to the only instance of supervolcanism on Mars, which may have occurred almost 4 billion years ago. In chapter 2, soil chemistry trends are examined within the northern lowlands in an effort to uncover the extent of aqueous alteration in the region. In contrast to other theories which posit the lowlands of Mars were home to an ocean, we find no geochemical evidence to suggest the presence of an ocean-scale body of water within the lowlands. In chapter 3, we examine seismic velocity estimation through the use of numerical models designed to estimate p-wave velocity in unconsolidated sediments. These models have been used terrestrially for studies in different settings, from beach sands to permafrost environments, both of which are broadly applicable to Mars. We compare our model outputs with the velocities derived by the InSight team through analysis of in-situ seismic data from Mars and find that we are able to recreate their results. We also note that the presence of a layer of very fine-grained sediment dominated by cohesion forces accounts for the high errors on s-wave velocity estimations at the InSight landing site.
These chapters illustrate the utility of remote sensing data and how it can be used to inform our models and scientific investigations. Remote sensing methods remain the most accessible way for us to learn about geologic process on celestial bodies. The scale and amount of data that can be acquired through satellite observation provides a wealth of resources for future study. The continued analysis of remote data, application of new techniques, and development of new tools for remote analysis are crucially important for the advancement of planetary science and exploration.
Date
3-18-2024
Recommended Citation
Bates, Augustus, "A History of Fire and Ice on Mars: Using Remote Sensing to Examine the Chemical Origins of Volcanism, Liquid Water, and Regolith-Ice on Mars" (2024). LSU Doctoral Dissertations. 6363.
https://repository.lsu.edu/gradschool_dissertations/6363
Committee Chair
Karunatillake, Suniti. Lorenzo, Juan M.