Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9522124 | Earth and Planetary Science Letters | 2005 | 15 Pages |
Abstract
A field study of the surface rupture of the 14 November 2001, Mwâ¼7.9 Kokoxili (or Kunlun Shan) earthquake near Hongshui Gou (35.9° N, 92.2° E), a site with exceptional geomorphic offsets long identified on SPOT images, yields bounds on this earthquake return time and on the slip-rate along the Kusai Hu segment of the Kunlun Fault. Measurements of the sinistral coseismic and cumulative offsets of four distinct strath-terrace risers and of rill channels incised in the adjacent fan bajada, complemented by post-earthquake, metric-resolution satellite image restoration, are 3 ± 0.5 m, 6 ± 1 m, 31 ± 2 m, 63 ± 5 m, and 110 ± 10 m. The smallest offset is unambiguously that of the 14/11/2001 earthquake. The 31 and 63 m riser offsets, which have thermoluminescence ages of 2885 ± 285 and 5960 ± 450 yr, respectively, imply an average slip rate of 10.0 ± 1.5 mm/yr, almost identical to that found 200 km eastwards, in Xidatan, using 10Be cosmogenic dating of surface pebbles. The repetitive seismic slip (â¼3 m) implies an average recurrence time of 300 ± 50 yrs for earthquakes comparable to the 14/11/2001 event. This new data increases the body of evidence suggestive of local characteristic slip during large earthquakes and firmly corroborates the millennial eastward extrusion rate (1 cm/yr) of north-central Tibet relative to the Qaidam.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Earth and Planetary Sciences (General)
Authors
Li Haibing, Jérôme Van der Woerd, Paul Tapponnier, Yann Klinger, Qi Xuexiang, Yang Jingsui, Zhu Yintang,