WITHDRAWN Satellite Geodetic Measurement of the Coseismic and Postseismic Displacements from the January 2025 Mw 7.1 South Tibet Earthquake
Description:
WITHDRAWN We analyzed synthetic aperture radar (SAR) images from the Copernicus Sentinel-1A satellite operated by the European Space Agency for the coseismic displacements of magnitude (USGS Mww) 7.1 earthquake in southern Tibet. We use SAR interferometry (InSAR) measurements of displacements in the radar line-of-sight directions and pixel offset tracking to measure both the large displacements close to the rupture and the smaller displacements at larger distances. The InSAR coherence with Sentinel-1 radar (6 cm wavelength) is good in the dry Tibetan Plateau north of the High Himalaya. We combine InSAR data from different radar look directions to estimate two components of the surface displacement, and we concentrate on the east and vertical components. The north-south component of slip is measured by the along-track pixel offsets of the Sentinel-1 SAR images but with much coarser accuracy than the slant-range or across-track pixel offsets and InSAR. The large-scale deformation due to slip at depth is dominated by vertical downward motion of about 2 meters just west of our interpreted fault, accompanied by westward motion on the west side and eastward motion on the east side, all consistent with normal fault slip on a north-northeast-striking and west-dipping fault plane. The along-track pixel offsets indicate a probable significant oblique left-lateral slip component of the rupture. The main fault rupture likely reached the surface with close to 1 meter of dip-slip displacement and the surface rupture appears to have small but noticeable variations in strike with a 5-10 km wavelength. This earthquake occurred in an area of substantial interseismic strain identified in our time-series analysis of ten years of Sentinel-1 InSAR data under a related project.
Session: Late-breaking on Recent and Future Large Earthquakes [Poster]
Type: Poster
Date: 4/15/2025
Presentation Time: 08:00 AM (local time)
Presenting Author: Eric
Student Presenter: No
Invited Presentation:
Poster Number: 144
Authors
Eric Fielding Presenting Author Corresponding Author eric.j.fielding@jpl.nasa.gov Jet Propulsion Laboratory |
Robert Zinke robert.zinke@jpl.nasa.gov Jet Propulsion Laboratory |
Gilles Peltzer peltzer@ucla.edu University of California, Los Angeles |
Cole Speed cole.speed@jpl.nasa.gov Jet Propulsion Laboratory |
Grace Bato mary.grace.p.bato@jpl.nasa.gov Jet Propulsion Laboratory |
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WITHDRAWN Satellite Geodetic Measurement of the Coseismic and Postseismic Displacements from the January 2025 Mw 7.1 South Tibet Earthquake
Category
Late-breaking on Recent and Future Large Earthquakes