Abstract
Cosmogenic dating, using in situ (26)Al and (10)Be in quartz pebbles from alluvial terrace surfaces, constrains the late Holocene slip rate on the Xidatan segment of the Kunlun fault in northeastern Tibet. Two terrace risers offset by 24 +/- 3 and 33 +/- 4 m, having respective ages of 1788 +/- 388 and 2914 +/- 471 yr, imply a slip rate of 12.1 +/- 2.6 mm/yr. The full range of ages obtained (less than or equal to 22.8 k.y., most of them between 6.7 and 1.4 k.y) confinn that terrace deposition and incision, hence landform evolution, are modulated by post-glacial climate change. Coupled with minimum offsets of 9-12 m, this slip rate implies that great earthquakes (M similar to 8) with a recurrence time of 800-1000 yr, rupture the Kunlun fault near 94 degrees E.