Archeological Monuments: Evidence of Strong Earthquakes in the Past (Using the Example of the Southwestern Part of the Issyk-Kul Lake Region, the Tien Shan)

• Published in: Izvestiya. Atmospheric and oceanic physics 2021-12, Vol.57 (11), p.1396-1413
• Main Authors: Korzhenkova, L. A., Korzhenkov, A. M., Rodkin, M. V., Strelnikov, A. A., Makeev, V. M., Gladkov, A. S., Deev, E. V., Mazeika, J. V., Fortuna, A. B.
• Format: Article
• Language: English
• Subjects: Archaeology; Climatology; Compression; Compression tests; Data compression; Deformation; Earth and Environmental Science; Earth Sciences; Earthquakes; Fault zones; Faults; Geological hazards; Geophysics/Geodesy; Ground motion; Hazard assessment; Lake basins; Lakes; Paleogeology; Seismic activity; Seismic hazard; Seismicity; Seismology; Villages
• ISSN: 0001-4338; 1555-628X
• DOI: 10.1134/S0001433821110050

This paper presents new materials and summarizes existing ones on archeoseismology studies of stony walls conducted in the Alabash-Konurolyong intramountain depression (southwestern Issyk-Kul Lake region, the northern Tien Shan). The remnants of a sublatitudinal stone wall north of the village of Kyoksay, the remnants of buildings on the Duvana pass, the “long” submeridional wall north of the village of Alabash, and ruins of the fortress of the same name located on the Alabash pass have been studied. The deformations allow us to proceed to quantitative characteristics of two seismic events that occurred in the 15th and 18th centuries. The significant PGV values (on average, 1–3 m/s) are in good agreement with results of an analysis of data on the strong ground motions and correspond to the nearest near-fault zone. These values, in accordance with the morphostructural and other paleoseismologic data, point to the vicinity (within the limits of a few kilometers) of the corresponding seismogenic fault generating them and to the development of thrust deformations of compression. Paleoseismologic data, in particular, the results of PGV value assessments, indicate the significantly larger seismic hazard of the southern shore of the Issyk-Kul Lake depression than is shown in the modern map of seismic hazards of Kyrgyzstan. We assess seismic intensity values for our investigated localities as I  = 9.0 ± 0.5. Thus, according to preliminary paleoseismology data, the seismicity level of the southern part of the Issyk-Kul Lake basin is analogous to the seismicity of its northern part. These data can be used in reevaluating the seismic hazard of the investigated territory.