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Gravity Mapping to Validate the Rock Valley Geological Framework Model

Description: 

As part of the ongoing Source Physics Experiment, its third phase, known as the Rock Valley Direct Comparison (RVDC) effort is underway. This experiment seeks to compare the signatures recorded from a large chemical explosion emplaced very near to an historic earthquake, whose signatures were well recorded with nearby instrumentation. As part of this effort, a detailed Geologic Framework Model (GFM) was developed that included projections of the many known faults throughout Rock Valley. Efforts to improve seismic event locations include the use of the GFM and updates to seismic velocity, as well as a re-evaluation of the attitude and location at depth of relevant faults.

We have acquired several lines of relative gravity data using a LaCoste & Romberg portable gravimeter to improve the observation density over previous data available from the U.S. Geological Survey. Our aim is to validate or update the GFM and its fault projections as appropriate through these dense data, and to provide a Bouguer Gravity map to be used in future joint gravity/seismic inversion to further update the model and improve locations for previously recorded earthquakes. We present our observations, data reductions, modeling methods and comparison with the existing GFM. The gravity modeling is undertaken using open-source Python-based SimPEG software (Cockett et al., 2015).

References:

Cockett, Rowan, Seogi Kang, Lindsey J. Heagy, Adam Pidlisecky, and Douglas W. Oldenburg. "SimPEG: An Open Source Framework for Simulation and Gradient Based Parameter Estimation in Geophysical Applications" Computers & Geosciences, September 2015. doi:10.1016/j.cageo.2015.09.015

Session: Advancements in Forensic Seismology and Explosion Monitoring [Poster Session]

Type: Poster

Date: 5/2/2024

Presentation Time: 08:00 AM (local time)

Presenting Author: Nishath

Student Presenter: No

Invited Presentation: 

Authors