Neogene Paleoseismic Events and the Shanwang Biota's Burial in the Linqu Area,Shandong Province,China  

作　　者：TIAN Hongshui A.J.(Tom) VAN LOON ZHANG Zengqi ZHANG Shenhe ZHANG Banghua Lü Mingying LI Fuchang MA Xuemin 

机构地区：[1]School of Civil Engineering,Shandong Jianzhu University [2]Geological Institute,Adam Mickiewicz University [3]Shandong Institute and Laboratory of Geological Science [4]Linqu Shanwang Fossils Museum of Shandong Province

出　　处：《Acta Geologica Sinica(English Edition)》2015年第4期1103-1119,共17页地质学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (NSFC-41272066);the Program for Changjiang Scholars & Innovative Research Team of the University of China (IRT-13075)

摘　　要：Several paleoseismic events are recorded in the Neogene Linqu Group, exposed in the Linqu area, Shandong Province, China. The events were interpreted on the basis of fleldwork and laboratory analysis, which showed the presence of seismites with plastically deformed soft-sediment deformation structures in the Shanwang Formation, and of seismic volcanic rocks in the Yaoshan Formation which show brittle deformation. The earthquake-triggered soft-sediment deformations in the seismites include load structures, ball-and-pillow structures, flame structures, piUow-like beds, boudinage structures, slump folds, syn-depositional faults, veins of liquefied sand, and dikes of liquefied sandy lime-mud. The seismic activity is also reflected in what might be called ＇brittle seismites＇; these originated when, under the influence of seismic vibrations, semi-consolidated conglomerate was shattered. Moreover, volcanic activity is related to intense earthquakes that affected basalts intercalated with sand layers; these successions are known as ＇seismic volcanic rocks＇, which are characterized by veins of liquefied sand intruding the basalts. AH above traces of paleoseismic activity were left from one single time span of 4 Ma with active seismicity that took place 14-10 Ma. This time span is known as ＇the Linqu Neogene Paleoseismic Active Period＇, which is divided into four paleoseismic episodes, which were responses to tectonic extension and basin rifting in this area. It even includes the activity of the Yishu Fault Zone during the Miocene and the Neogene. The ratios of trace elements in the seismites, w（La）/w（Sc） and w （La）/w（Th） are higher than the average value of the upper crust, but w（Th）/w（Sc） is lower; this is geochemical evidence for the basin rifting that resulted in a high sedimentation rate. The intense and frequent paleo-earthquakes are held responsible for the rapid burial of the Shanwang Biota. Secondary earthquake-induced processes （e.g. slumping of a lake shore and the strongly Several paleoseismic events are recorded in the Neogene Linqu Group, exposed in the Linqu area, Shandong Province, China. The events were interpreted on the basis of fleldwork and laboratory analysis, which showed the presence of seismites with plastically deformed soft-sediment deformation structures in the Shanwang Formation, and of seismic volcanic rocks in the Yaoshan Formation which show brittle deformation. The earthquake-triggered soft-sediment deformations in the seismites include load structures, ball-and-pillow structures, flame structures, piUow-like beds, boudinage structures, slump folds, syn-depositional faults, veins of liquefied sand, and dikes of liquefied sandy lime-mud. The seismic activity is also reflected in what might be called ＇brittle seismites＇; these originated when, under the influence of seismic vibrations, semi-consolidated conglomerate was shattered. Moreover, volcanic activity is related to intense earthquakes that affected basalts intercalated with sand layers; these successions are known as ＇seismic volcanic rocks＇, which are characterized by veins of liquefied sand intruding the basalts. AH above traces of paleoseismic activity were left from one single time span of 4 Ma with active seismicity that took place 14-10 Ma. This time span is known as ＇the Linqu Neogene Paleoseismic Active Period＇, which is divided into four paleoseismic episodes, which were responses to tectonic extension and basin rifting in this area. It even includes the activity of the Yishu Fault Zone during the Miocene and the Neogene. The ratios of trace elements in the seismites, w（La）/w（Sc） and w （La）/w（Th） are higher than the average value of the upper crust, but w（Th）/w（Sc） is lower; this is geochemical evidence for the basin rifting that resulted in a high sedimentation rate. The intense and frequent paleo-earthquakes are held responsible for the rapid burial of the Shanwang Biota. Secondary earthquake-induced processes （e.g. slumping of a lake shore and the strongly

关 键 词：Paleo-seismic event Shanwang biota rapid burial Linqu NEOGENE 

分 类 号：Q911[天文地球—古生物学与地层学] P534[生物学—古生物学]