Geology PhD Candidate
University of Oklahoma
Alicia L. Bonar
Header photo: Early-Mid Permian strata near the Jemez Mountains in northern New Mexico
I'm interested in understanding the relationship between paleoclimate and paleogeography, with an emphasis on how changes in these two large-scale systems are recorded in fine-grained sedimentary rocks.
SIGNIFICANCE & MOTIVATION
Sedimentary rocks account for over 75% of Earth’s surface, and the sedimentary rock record preserves critical information for understanding the evolution of sedimentary basins and Earth's past climates.
I am particularly interested in fine-grained sedimentary deposits from icehouse periods, including the late Paleozoic and Neoproterozoic. The late Paleozoic ice age was the first and only time our planet has transitioned from an icehouse climate to a greenhouse climate with an evolved terrestrial biosphere, likely very similar to what we are experiencing on Earth today. The fine-grained sedimentary rock record is particularly interesting to me because of it's broad-range of applications related to source-to-sink systems, the long term carbon cycle, climate forcings, and pedogenesis.
CURRECT RESEARCH
Climatic influences on silt generation in modern soils
The generation of silt to form loess deposits has been linked to a variety of geomorphological processes including chemical weathering during pedogenesis. Some authors suggest that this process can generate up to 50 – 75% in situ silt contents from granitoid bedrock in tropical, equatorial, and Mediterranean climates. For this project, we are analyzing the geochemistry and potential origins of silt in a granitoid-host soils from variety of climate regions including Puerto Rico, the Anza Borrego Desert in California, northeastern Spain, and southern France.
University of Oklahoma undergraduate students Bren Cable and Taylor Ramsey In Catalonia helping collect soil samples
Admiring our beautiful dust trap!
Field season cohort enjoying the Mediterranean Sea
University of Oklahoma undergraduate students Bren Cable and Taylor Ramsey In Catalonia helping collect soil samples
Mike Soreghan explaining the tectonic history and modern drainage networks to Late Tanganyika in field site west of Kalinzi, Tanzania.
Links between voluminous loess deposits and icehouse climates in deep time
Dust and aerosols are known to impact (and record) modern and ancient climate, especially during icehouse conditions. Loess deposits have been documented from the Last Glacial Maximum as well as the late Paleozoic ice age, and in this project, we are exploring the record of loess deposits in the Neoproterozoic. Current work on this project is being conducted on the Manyovu Redbeds east of Lake Tanganyika, Tanzania.
The role of atmospheric dust in the formation of organic-rich mudrocks
Project details coming soon!
PAST RESEARCH
The Abo Unit of Salinas Pueblo Missions National Monument near Abo Pass field site in central New Mexico (although, we are pretty sure the stones are the Yeso Formation, not the Abo!).
Early Permian sediment transport systems during the final phase of Ancestral Rocky Mountain orogenesis
I worked on a provenance and sediment dispersal study for the Early Permian (Wolfcampian) Abo Formation throughout New Mexico for my masters thesis at New Mexico State University with Dr. Brian Hampton. The Ancestral Rocky Mountain system is still extensively researched due to it's ambiguous tectonic history, and this study supports the hypothesis that sediment transport systems of late Paleozoic Pangea are complex with influences from both fluvial and eolian transport mechanisms.
This project currently has one publication in NMGS Special Publication 14 and one publication in preparation.
My advisor at NMSU (Dr. Brian Hampton) and I "touching" re-exposed basement rock of the ARM Pedernal uplift. This area is private land, so unfortunately we could not get much closer!