Geomorphological and sedimentary records of Late Quaternary activities of Qiaojia-Jinyang segment of Lianfeng fault zone, Southwest China

Lianfeng fault zone (LFZ) in Southwest China has great significance for understanding the seismogenic environment, but its nature and latest active age is still poor constrained up to now. The Qiaojia-Jinyang segment (QJS) of LFZ intersects with Jinsha River; so well-developed river terraces provide a potential spatio-temporal constrains recent faulting QJS. Based on investigation terrace deposits along river, this paper makes detailed logging dating liquefaction Combined previous data, sequence Late-Quaternary area was redetermined. It considered that T1 (lowest) T2 at QJS (~ 10–20 m 60–70 m, respectively, above local level) are roughly developed Middle Holocene Late Pleistocene, indicating valley strongly undercut since Pleistocene. analysis morphological characteristics, spatial distribution, material composition intersecting relationship between sand veins layers, strong ground motions preliminarily detected, which indicates seismic activity during Quaternary. characteristics data strata within profiles deposits, it least QJS, time not earlier than Early-Middle Holocene. These findings clear geological evidences seismicity assessment LFZ, help regional tectonic environment prevention earthquake disasters.