Semester of Graduation

Summer 2026

Degree

Master of Science (MS)

Department

Geology and Geophysics

Document Type

Thesis

Abstract

Many tens of ice rises exist at the marine margins of the Antarctic Ice Sheet. Isle-type ice rises in particular are those where an ice shelf is pinned to an underlying submarine bank. Recent and ongoing studies show that Ross Bank, on the middle continental shelf of central Ross Sea, was the former site of an important Ross Ice Shelf ice rise during the advance and retreat of the West Antarctic Ice Sheet (WAIS) in the last glacial cycle. Ross Bank is a broad and anomalously shallow water platform whose crest rises to 170 m water depth. Despite their importance as a buttressing site, little is known about how, when and why shallow submarine banks form. Here, we use a grid of new seismic data acquired during expedition NBP2301 with legacy seismic surveys to reconstruct how Ross Bank morphology evolved. Our seismic-based correlations and mapping show that Ross Bank partly overlies the western flank of the Central High, a large basement horst created during the Cenozoic rifting of Ross Sea. Seismic correlation to lithologic and chronologic control at DSDP Leg 28 and IODP Expedition 374 sites indicates that a thick stack of prograding grounding zone wedges were deposited at the site of Ross Bank during the early Miocene. Prior to the end of the early Miocene, WAIS ice streams deeply eroded into wedges at the sites of Glomar Challenger Basin and Pennell Trough creating approximately 400 meters of relief. Only minor aggradation at Ross Bank with additional down-cutting erosion of the adjacent troughs by ice-stream have occurred during subsequent advances of the WAIS to the outer continental shelf created additional relief. Our analyses make the case that a shallow submarine area hosted ice rises at Ross Bank since the end of the early Miocene

Date

6-11-2026

Committee Chair

Bart, Philip J.

LSU Acknowledgement

1

LSU Accessibility Acknowledgment

1

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