Date of Award

2024-08-01

Degree Name

Master of Science

Department

Geophysics

Advisor(s)

Marianne S. Karplus

Abstract

Seismic exploration has played a crucial role in understanding the Earth's interior and has been successfully employed in various regions, including Antarctica. This research focuses on analyzing a 1000-m seismic line on McMurdo Ice Shelf near Williams Airfield, as part of the Thwaites Interdisciplinary Margin Evolution (TIME) project. The McMurdo Ice Shelf, covering an expansive area within the Ross Ice Shelf, has undergone significant changes due to evolving oceanic and atmospheric conditions. The presence of Circumpolar Deep Water (CDW) has recently impacted the ice shelf, with warmer ocean waters causing basal melting and changes in wind patterns affecting ice flow and stability. Seismic data were analyzed from 24 seismic nodes recording for 30 days from December 2021 to January 2022. Both passive and active seismic sources were captured with controlled seismic sources generated by a 12-lb sledgehammer. This thesis focuses on the active seismic data and tests the effectiveness of the sledgehammer source for seismic reflection imaging. The objective of this study is to develop a comprehensive velocity model for the area and image the ice shelf, McMurdo Sound, and the seafloor beneath. The hammer signals generated 100-200 Hz frequencies observed in the spectrograms and were used to develop a seismic image. The hammer was a reliable and efficient source identifying two layers; transition from ice shelf to sea (~100 m depth) and sea bed boundary (~900 m). This new seismic image corroborates findings from previous studies, such as the ANDRILL project, by identifying similar stratigraphic units and subsurface interfaces.

Language

en

Provenance

Received from ProQuest

File Size

57 p.

File Format

application/pdf

Rights Holder

Yeshey Seldon

Download

Share

COinS