Abstract:
Several seismo-depositional layers developed in the thick bedded alluviums of the Paleogene Zhubidian Formation in the Anqiu-Xiazhuang half graben along the Tancheng-Lujiang fault zone. They were a suit of seismites composed of the seismic liquefaction, seismic-fissure filling, vibration falling, seismic fracturing and earthquake settling. Based on the field survey, laboratory examination as well as comparative seismogeologic study, the authors recognized many seismite structures such as liquefied sand vein, liquefied sand dyke, liquefied sand mass, sandy conglomerate dyke by fissure filling, seismic fall-mass, small-scale seismic intra-layer fracture and seismo-settlement structure, etc. According to features of these seismite structures and some relevant research references, a new seismo-depositional succession of alluvial facies sediments, consisting of A, B and C units, was established in the paper. The unit A was formed by strong vibration liquefaction of water-saturation sand at first, then the unit B formed by seismic-fissure filling and vibration falling, and the unit C produced by intra-layer fracturing and ground settling at last, which reflected the whole seismic function of the thick bedded alluviums. To synthesize the analysis of regional geology and research results before, we proposed that the Paleogene seismites in Anqiu area, Shandong, should be a responses to the intense tectonic activity and strong earthquakes of the Tancheng-Lujiang fault zone during Early Cenozoic.
Tian Hongshui,Zhang Zengqi. SEISMITE SUCCESSION OF THE PALEOGENE ALLUVIUM ALONG THE TANCHENG-LUJIANG FAULT ZONE IN ANQIU AREA, SHANDONG[J]. Chinese Journal of Geology, 2006, (2): 208-216.