引用本文：李传友,张培震,袁道阳,王志才,郑德文.2010.活动走滑断裂上断塞塘沉积特征及其构造含义[J].地质学报,84(1):90-105. Li Chuanyou,Zhang Peizhen,Yuan Daoyang,Wang Zhicai,zheng de wen.2010.Characteristics of the sediments in sag-pond on the active strike slip fault and its tectonic implications[J].Acta Geologica Sinica,84(1):90-105.
Abstract:The active faulting is closely related to the earthquake and geologic hazard. Study on the relevant deposits can help to understand the active behavior and pattern of an active fault. By disclosing the sedimentary formation of typical faulted landform, the sag-pond, can learn about the record of active strike-slip faulting by sag-ponding deposits. By disclosing a representative sag-pond with 3-D excavation along the Huangxianggou segment of the active West Qinling fault in noreastern Tibet Plateau, depositional features of the sag-pond are analized, and the sag-ponding sequence is constructed. Study shows, the stratigraphic sequence exhibits good rhythms in each pond. One rhythm is composed of the lower coarse layers and the upper fine layers, and the grain size is coarser below and finer upward. The coarse layers are commonly constituted by fine sand, coarse sand and gravels, which suggests a fast depositing. The finer layers generally consist of carbonaceous clay, mild clay and silty sand, showing characteristics of lacustrine sedimentation. The sag-ponding deposition sequence is multi-staged, and one deposition rhythm corresponds to a series of formation deposited in a period. Observations indicate that the deposition rhythms are concerned with the periodic behavior of the faulting. This study is a basis on revealing the tectonic evolution and active pattern, deducing the strike-slipping history and forecasting the future behavior of a strike-slip fault.