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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. [ABSTRACT FROM AUTHOR]

We have studied paleoseismicity along the adyr (piedmont) Kokonadyr–Tegerek fault zone in the SW Issyk-Kul region. We have shown that although earthquake slip continues in the tectonic contact zone between the Paleozoic rocks of the Kokonadyr–Tegerek uplift and the Quaternary deposits of the Alabash–Konuroleng trough, still most earthquake-generating ruptures visible at the surface are moving for some hundreds of meters southward from the abovementioned adyr fault. This process leads to the formation of multislip earthquake scarps and compensation grabens behind them. Radiocarbon dating identified four large Holocene earthquakes along the Kokonadyr–Tegerek fault zone that occurred during the following time spans: 1771‒1785, 1440‒1515, as well as probably 2310–745 B.C. and 6400–5300 B.C. Judging from the parameters of these ruptures, or earthquake scarps, their magnitudes were greater than or equal to 7 and the intensity of shaking was Io ≥ IX. Vigorous seismic activity has gone on along the Kokonadyr–Tegerek fault zone since at least the Middle Quaternary. The relevant evidence includes uplifted and abandoned valleys of this age in the eponymous uplift and considerable accumulations of lacustrine deposits in the northern Alabash–Konuroleng depression. The thick sedimentary sequence was caused by glacier melting on the northern slope of the Terskei Ala-Too mountain range, while the abandoned valleys indicate considerable tectonic damming. The most suitable model to explain the formation of adyrs (piedmont areas or foothills) in the southern Issyk-Kul basin seems to be a model that envisages a low-angle northward propogating or southward dipping main fault that is complicated with reverse movements. All the materials acquired in this study can be used to develop a new Earthquake Hazard Map for the Republic of Kyrgyzstan. [ABSTRACT FROM AUTHOR]