Detection of Crustal Deformation of the Northern Pakistan Earthquake by Satellite Data

By Argilli Lydia | Wed, 2 Feb 2011 - 14:34
Pakistan

 

A large-scale earthquake with a magnitude of 7.6 occurred on October 8, 2005 in the northern part of Pakistan. The Geographical Survey Institute (GSI) carried out various analyses to clarify in detail with the data from satellites the crustal deformation accompanying the earthquake.

GSI mapped the crustal deformation spatially with Synthetic Aperture Radar data from the European Space Agency’s ENVISAT, and found that the newly deformed area occupies a 90-kilometer-long northwest-southeast trending strip. The heavily damaged area north of Muzaffarabad has the maximum deformation up to 6-meter uplift as observed by the satellite.

There are known active faults stretching to the northwest and southeast near the epicenter, which reveal some uplift (on the northeastern side) and dextral (right-lateral) strike-slip activity. The detected crustal deformation was along these active faults and all observations were consistent with previously known directions of past fault movements. Model calculations also showed that the faults slipped a maximum of about nine meters.

In addition, analysis using other high-resolution images from IKONOS and SPOT-5 satellites showed that slope failures occurred along the active faults and were concentrated on their northeastern side.

Hiroshi, U., Fujiwara, S., Tobita, M., Ozawa, S., Sato, H. & M. Koarai (2006): Detection of Crustal Deformation of the Northern Pakistan Earthquake by Satellite Data. Proceedings of the international Symposium on Space Technology and Science, Vol 25, 1649-1653.

Geographical Survey Institute of Japan