煤田地质与勘探2023，Vol.51Issue(12)：38-46,9.DOI:10.12363/issn.1001-1986.23.11.0750
琼北地区铺前-清澜断裂北段的全新世活动新证据
New evidence for Holocene activity of the northern segment of the Puqian-Qinglan fault in northern Hainan Province
摘要
Abstract
The Puqian-Qinglan fault,located in northern Hainan Province,is closely related to the judgment of the seis-mogenic structure of the Qiongshan M7½ earthquake in 1605.To accurately determine the latest activity characteristics of this fault,this study,adopting artificial shallow seismic exploration with large-tonnage seismic sources combined with small-spacing cross-well stratigraphic correlation,investigated the sedimentary geological conditions of the Quaternary basalt cover and significantly thick marine sand layers in northern Hainan Province through exploration at Qishantou and Dongzhai villages in the Sanjiang Town,Jiangdong New Area,Haikou.Key results are as follows:(1)the Puqian-Qinglan fault dislocates multiple marker strata,with the shallowest dislocation occurring in the silt layer of the Holo-cene Yandun Formation and upper fault contacts'burial depths of approximately 10 m.As revealed by drilling,the fault surface exhibits significant strike-slip and thrusting properties,suggesting a large-scale fault zone with a certain width,multiple branches,and multi-stage activity;(2)Within the depth range revealed by the cross-well stratigraphic correla-tion,the displacement of the dislocated strata increases with depth.The Puqian-Qinglan fault has been active since 8 346-7 153 a cal BP.It exhibited a cumulative vertical displacement of 4-5 m during the Holocene,with vertical displacement rates of 0.53‒0.63 mm/a.Accordingly,it can be inferred that the Puqian-Qinglan fault serves as the seismogenic fault of the Qiongshan M7½ earthquake in 1605.The new evidence for the Holocene activity of the Puqian-Qinglan Fault ob-tained in this study provides a scientific basis for spatial land planning and regional seismic hazard assessment.关键词
铺前-清澜断裂/断裂活动证据/全新世/人工地震勘探/钻孔联合地质剖面/海南省北部Key words
Puqian-Qinglan fault/fault activity evidence/Holocene/artificial shallow seismic exploration/cross-well stratigraphic correlation/Northern Hainan Province分类
天文与地球科学引用本文复制引用
刘华国,贾伟,李昌隆,李峰,贾启超,王志成,张攀,林镇,张杰汉,施春花,张彦博..琼北地区铺前-清澜断裂北段的全新世活动新证据[J].煤田地质与勘探,2023,51(12):38-46,9.基金项目
中国地震局城市活断层探测与地震危险性评价项目(2240506) （2240506）
海口江东新区活动断层精细探测项目 （）
