Co-seismic Vertical Offset Retrieval From High-Resolution, Stereogrammetric DEMs: Examples from the 2013 Baluchistan, Pakistan Earthquake

William D. Barnhart, Hannah Shea, Katherine Peterson, Ryan D. Gold, Rich Briggs, & David J. Harbor

Published July 26, 2018, SCEC Contribution #8205, 2018 SCEC Annual Meeting Poster #125

We highlight recent advances in the quantification of vertical offsets generated by earthquakes from time series of high-resolution stereogrammetric DEMs, with a focus on the 2013 Mw7.7 Baluchistan, Pakistan strike-slip earthquake. Topographic data sets, such as digital elevation models (DEMs) and LiDAR point clouds, are invaluable resources in the Earth science community that provide a base data set for numerous applications, including hydrological modeling, geomorphic and structural mapping, landscape evolution analysis, and orthorectification of remotely sensed imagery. In the field of active tectonics, topographic data sets allow for the characterization of regional elevation patterns, identification and quantification of discrete fault offsets, modeling of localized and regional fluvial responses to lateral and vertical fault displacements, and mapping of active fault traces, among other applications. The growing availability of sub-meter resolution satellite imagery further enhances and expands the applications of these data sets by allowing for both unprecedented spatial resolution and the generation of topographic time series. In this talk, we first present a suite of pre- and post-event 2-m resolution DEMs derived from commercial optical imagery and open source stereogrammetric tools that span the 2013 earthquake rupture. We highlight how various differencing schemes may introduce biases into the derived vertical offset field. Using the Iterative Closest Point (ICP) approach, we then provide a spatially dense vertical offset field for the 2013 earthquake and compare our results to previous vertical measurements made by manual mapping of post-event DEMs. Last, we provide an assessment of the shortcomings of our approach and means to overcome these issues, and future directions and applications of differential topography in the study of the earthquake cycle.

Key Words
Geodesy, High Resolution Topography, Earthquake ruptures

Citation
Barnhart, W. D., Shea, H., Peterson, K., Gold, R. D., Briggs, R., & Harbor, D. J. (2018, 07). Co-seismic Vertical Offset Retrieval From High-Resolution, Stereogrammetric DEMs: Examples from the 2013 Baluchistan, Pakistan Earthquake. Poster Presentation at 2018 SCEC Annual Meeting.

Related Projects & Working Groups
Tectonic Geodesy