Exploring Earth's dynamic surface wIth large topographic inversions

Smith, Adam George Guy (2024) Exploring Earth's dynamic surface wIth large topographic inversions. PhD thesis, Birkbeck, University of London.

Abstract

Understanding the interplay between tectonics and climate is crucial to inferring topographic evolution, a first order control on the Earth system. River networks are sensitive to changes in rock uplift and erodibility, such that this information can be extracted from them through quantitative modelling. One model that has been used extensively to this end is the stream power incision model (SPIM). For almost half a century, researchers have used the SPIM, revolutionising our understanding of river and landscape evolution. However, over time, several different approaches to working with the SPIM have been developed, and it is not clear which approaches are most appropriate, accurate and useful for a given scenario. The work presented in this thesis begins with a review and assessment of the commonly employed approaches to river network analysis. When there is spatial variation in rock uplift and erodibility in landscapes, I show that using a linear inverse scheme that discretises networks in 2-dimensions is the most useful approach. I therefore use this approach to develop a new methodology to infer the SPIM parameter $m/n$. With synthetic landscapes, I show that this new methodology can more accurately infer $m/n$ compared to existing methodologies when spatial variation exists in landscapes. These inverse approaches are then used alongside geological and geophysical data sets to investigate spatial and temporal variations in rock uplift and erodibility in the Wasatch Range and the Uinta Mountains, both in Utah. In the Wasatch, an inversion for the rock uplift rate history reveals a control of climate-driven lake filling on rock uplift rate variation. In the Uintas, a lithospheric drip is identified as driving topographic rejuvenation in the region. These case studies demonstrate how topographic inversions can be used to gain new information on the interactions of tectonics and climate at the Earth's surface.

Metadata

Statistics

DownloadsShow export options

Export as XMLJSONCSV

Activity Overview

6 month trend

0Downloads

6 month trend

32Hits

Additional statistics are available via IRStats2.

Archive Staff Only (login required)

Edit/View Item