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The Talas-Fergana Fault,the largest strike-slip structure in Central Asia,forms an obliquely oriented boundary between the northeastern and southwestern parts of the Tianshan mountain belt. The fault underwent active right-lateral strike-slip during the Paleozoic,with right-lateral movements being rejuvenated in the Late Cenozoic. Tectonic movements along the intracontinental strike-slip faults contribute to absorb part of the regional crustal shortening linked to the India-Eurasia collision; knowledge of strike-slip motions along the Talas-Fergana Fault are necessary for a complete assessment of the active deformation of the Tianshan orogen. To improve our understanding of the intracontinental deformation of the Tianshan mountain belt and the occurrence of strong earthquakes along the whole length of the Talas-Fergana Fault,we identify features of relief arising during strong paleoearthquakes along the Talas-Fergana Fault,fault segmentation,the length of seismogenic ruptures,and the energy and age of ancient catastrophes. We show that during neotectonic time the fault developed as a dextral strike-slip fault,with possible dextral displacements spreading to secondary fault planes north of the main fault trace. We determine rates of Holocene and Late Pleistocene dextral movements,and our radiocarbon dating indicates tens of strong earthquakes occurring along the fault zone during and interval of 15800years. The reoccurrence of strong earthquakes along the Talas-Fergana Fault zone during the second half of the Holocene is about 300 years. The next strong earthquake along the fault will most probably occur along its southeastern chain during the next several decades. Seismotectonic deformation parameters indicate that M>7earthquakes with oscillation intensity I>IX have occurred.
The Talas-Fergana Fault, the largest strike-slip structure in Central Asia, forms an obliquely oriented boundary between the northeastern and southwestern parts of the Tianshan mountain belt. The fault underwent active right-lateral strike-slip during the Paleozoic, with right- lateral movements being rejuvenated in the Late Cenozoic. Tectonic movements along the intracontinental strike-slip problems contribute to absorb part of the regional crustal shortening linked to the India-Eurasia collision; knowledge of strike-slip motions along the Talas-Fergana Fault are necessary for a complete assessment of the active deformation of the Tianshan orogen. To improve our understanding of the intracontinental deformation of the Tianshan mountain belt and the occurrence of strong earthquakes along the whole length of the Talas-Fergana Fault, we identify features of a canceration arising strong strong paleoearthquakes along the Talas-Fergana Fault, fault segmentation, the length of seismogenic ruptures, and the e nergy and age of ancient catastrophes. We show that during neotectonic time the fault developed as a dextral strike-slip fault, with possible dextral displacements spreading to secondary fault planes north of the main fault trace. We determine rates of Holocene and Late Pleistocene dextral movements , and our radiocarbon dating indicates of strong earthquakes occurring along the fault zone during and interval of 15 800years. The reoccurrence of strong earthquakes along the Talas-Fergana Fault zone during the second half of the Holocene is about 300 years. The next strong earthquake along the fault will most likely occur occur along its southeastern chain during the next several decades. Seismotectonic deformation parameters indicate that M> 7 earthquakes with oscillation intensity I> IX have occurred.