The 13 April 2010 Mw 6.9
Yushu (Qinghai, China) Earthquake from InSAR observations
Zhenhong Li, COMET+, Department of
Geographical and Earth Sciences, University of Glasgow, United Kingdom
Wanpeng Feng, Institute of
Geophysics, China Earthquake Administration, Beijing, China
Tim Wright, COMET+, School of Earth
& Environment, University of Leeds
Barry Parsons, COMET+, Department
of Earth Sciences, University of Oxford
On 13 April 2010 (UTC 23:49:37, Local time
7:49:37, 14 April 2010), a large earthquake (Mw = 6.9) struck Yushu, Qinghai,
China. This event occurred on the Yushu fault that is part of the
Yushu-Garzê-Xianshuihe fault zone, one of the most active fault zones in
eastern Tibet.
Below
are some preliminary images about the 2010 Yushu earthquake. The SAR images
used in this research were provided by the Japanese Aerospace Exploration
Agency (JAXA) and European Space Agency (ESA) under a JAXA AO project and under
the ESA DRARONG-2 5305 and 5343 projects respectively. The ownership of PALSAR
data belongs to METI (Ministry of Economy, Trade and Industry) and JAXA, and
the ownership of Envisat data belongs to ESA. These images may be used for
press purposes with the attribution "Li et al. (2010), University of
Glasgow, COMET+" unless otherwise noted in the caption.
Figure 1. A rewrapped ALOS PALSAR interferogram from Path 487 (ascending: 100115-100417) superimposed on a hill-shaded SRTM DEM (kml file). Note: (1) The black line represents the surface rupture (txt file) derived from offset maps (Figure 2). (2) There might be an orbital ramp, although precise orbits were used in interferometric processing. (First generated on 19 April 2010 using predicted orbits; updated on 25 April 2010 using precise orbits)
Figure 2. ALOS offset
maps from Path 487 (ascending): (a) range offsets (kml
file); (b) azimuth offsets (kml
file). Note: Range offset map
shows the range change in the satellite line of sight (LOS) whilst Azimuth
offset map shows displacements in the azimuth direction (nearly North-South);
therefore the latter is sensitive to surface movements in the N-S direction.
Figure 3. A rewrapped ENVISAT ASAR interferogram from track 498 (ascending: 100215-100426) superimposed on a hill-shaded SRTM DEM (kml file). (updated on 30 April 2010)
Figure 4. Single-Fault Distributed slip model for ALOS PALSAR interferogram. Slip is concentred within the upper 20 km of the fault, peaking at 1.64 m at a depth of 3-6 km. The maximum slip in the top 3 km (i.e. near surface) is up to 1.4 m, which is consistent with offset maps. In addition, the InSAR-derived moment is 6.93, which is consistent with the GCMT moment. (updated on 25 April 2010)
Contact
Information
----------------------------------------------------------
Dr Zhenhong Li, FRSPSoc
Department of Geographical and Earth Sciences, University of
Glasgow
East Quadrangle, University Avenue, Glasgow G12 8QQ, United
Kingdom
Tel: +44 (0)141
330 2289; Fax: +44 (0)141 330 4894
Email: Zhenhong.Li@ges.gla.ac.uk; Web: www.ges.gla.ac.uk/staff/zli
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Links
COMET+: Centre for the Observation and Modelling
of Earthquakes, Volcanoes and Tectonics
COMET+ Yushu web article:
InSAR Observations of
Ground Displacements for the 2010 Magnitude 6.9 Yushu Earthquake, China
GEO's Qinghai
Supersite Event Website:
http://supersites.unavco.org/qinghai.php