Strong Seismic Activity of the Terskey Ala-Too Range Adyrs, Northern Tien Shan, in the Holocene from Radiocarbon Analysis Data
Abstract
Abstract—We studied historical and paleoseismic deformations in the southern Issyk-Kul depression—on the territory of adyrs (piedmonts) of the Terskey Ala-Too range: (1) along the southern foot of the Kokonadyr-Tegerek mountains in the Ala-Bash-Konur-Olen intermountain depression; (2) in the Tossor river basin; (3) in the Chon-Kyzyl-Suu river valley; and (4) on the northern slope of the intradepression adyr uplift of Bir-Bash. We used 21 results of radiocarbon dating of samples taken in the walls of paleoseismological trenches or cleared natural outcrops. These studies in the south of the Issyk-Kul depression revealed 10 strong seismic events during the Holocene. We found that they had migrated from the west—from the Ala-Bash-Konur-Olen depression in the early Holocene eastward—to Mount Bir-Bash (by the beginning of Anno Domini) and then again back—westward to the Kokonadyr-Tegerek foothills (by the end of the Late Middle Ages). Some of the discovered seismic catastrophes may have been the beginning or the end of the evolution of some civilizations in the region (the Andronovo culture and the Karakhanids). The obtained data can be used to make the New Map of Seismic Zoning for the Issyk-Kul Region of the Kyrgyz Republic.