地质学报2012，Vol.86Issue(8)：1320-1330,11.
山东诸城早白垩世莱阳期古地震事件与恐龙迁移
Paleoearthquake Events of Early Cretaceous Laiyang Stage and Dinosaur Migration in Zhucheng, Shandong Province, Eastern China
摘要
Abstract
Unusual, abundant dinosaur tracks have been discovered in Huanglonggou of Huanghua County in Jiaodong peninsula, eastern China. The tracks wee found to occur in the Yangzhuang Formation of Early Cretaceous Laiyang Group in south of Zhucheng faulted depression in Jiaolai basin. In this study, several sets of paleoearthquake records were found in the Yangzhuang Formation immediately in underlying and overlying track-bearing strata. Soft-sediment deformation structures include undulate fold, diapir, liquefied sand vein,- liquefied breccias, convolute deformation and seismite unconformity, and graded faults. Our analysis shows that initial sediments, sedimentary facies and tectonism determined structural deformation styles of soft sediments produced by seismic activities. During interim of sedimentation of early Cretaceous Laiyang Group, earthquakes were characterized by multiple periods and frequent occurrences, with unilateral compressional dome-trough structure and bi-directional compressional wavy deformation being predominant, and by increasing tectonic activities at late stage. Based on the identified paleo-earthquake development records and their magnitude analysis, it can be assumed that seismogenic fault was likely the Wulan fault, the southern segment of faulting in this period. Regional tectonic effect caused the change of sedimentary environments gradually from lacustrine to fluvial facies, and after outbreak of paleo-earthquakes, abundant tracks of dinosaur migration were left and preserved on lacustrine area. Paleoseismic records can help built the link between paleo-earthquake events and deposition environment and tectonic evolution, and constrain attributes, frequencies and time-limit of tectonism, thus providing the evidence for determination of basin, surrounding structure and sedimentary development关键词
软沉积物变形构造/古地震成因/恐龙足迹化石/早白垩世/山东诸城Key words
Soft-sediment deformation structure/ triggering of paleo-seism/ dinosaur tracks/ Early引用本文复制引用
何碧竹,乔秀夫,田洪水,张艳霞..山东诸城早白垩世莱阳期古地震事件与恐龙迁移[J].地质学报,2012,86(8):1320-1330,11.基金项目
本文为中石化科技部项目 (P05036)及国土资源部行业基金项目(编号201011034)共同资助的成果. （P05036）
