Paleoseismological studies in the epicentral area of the 1911 Kemin earthquake (northern Tien Shan)

• Published in: Russian geology and geophysics Vol. 57; no. 2; pp. 337 - 343
• Main Authors: Deev, E.V., Korzhenkov, A.M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2016; Allerton Press
• Subjects: 1911 Kemin earthquake; Aksu Fault; Asia; Cenozoic; Chon-Aksu Graben; Clusters; Commonwealth of Independent States; dams; Earthquakes; epicenters; fault scarp; Geological faults; Geophysics; Historic; Holocene; Issyk-kul Lake; Kemin earthquake 1911; Kichi-Aksu Graben; Kyrgyzstan; lakes; magnitude; natural dams; paleoseismicity; Pleistocene; Quaternary; Seismic phenomena; seismic quiescence; Seismology; Signatures; Tien Shan; Trenching; upper Pleistocene; Tien Shan; fault scarp; Aksu fault; paleoseismicity; 1911 Kemin earthquake
• ISSN: 1068-7971; 1878-030X
• DOI: 10.1016/j.rgg.2016.02.010

The area of the Chon-Aksu and Kichi-Aksu grabens abounds in seismic deformation produced by historic and prehistoric events, among which the great Kemin (Kebin) earthquake of 1911, with a magnitude of Ms - 8 and a shaking intensity of I0 = 10–11, generated by the Aksu fault. Trenching across a fault scarp of the 1911 event has revealed signatures of reverse slip resulted from another earthquake that occurred about 3000 years ago. Traces of a large event at ~12,700 yr BP appear in sediments of a tectonically dammed lake. The trenching results, along with radiocarbon dating and published evidence, show the Late Pleistocene-Holocene history of the Aksu fault to comprise prolonged quiescence periods separated by large earthquakes or earthquake clusters at 19,500-20,000, 12,700, 4000–3000, and <850 yr BP (including the 1911 Kemin shock).