New evidence for Holocene activity of the northern segment of the Puqian-Qinglan fault in northern Hainan Province
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摘要: 琼北地区铺前−清澜断裂是一条关系到1605年琼山7½级大地震发震构造判断的重要断裂。为准确厘定该断裂的最新活动特征，针对琼北地区第四纪玄武岩盖层和巨厚海相砂沉积等地质条件，采用大吨位震源的浅层人工地震勘探和小间距钻孔联合地质剖面探测相结合的方法，分别在海口江东三江镇岐山头村和东寨村展开探测。结果表明：(1)铺前−清澜断裂断错了多个标志地层，最浅断错至全新统烟墩组淤泥层，上断点埋深10 m左右，钻探所揭示的断层面明显具有走滑兼具逆冲性质，是一条具有一定宽度、多分支、多期次活动的大规模断裂带；(2)钻孔联合地质剖面所揭示的地层深度范围内，被断错地层的位移量随着深度增加而加大，铺前−清澜断裂自8 346~7 153 a cal BP以来有过活动，全新世累计垂直位移量4~5 m，垂直位移速率为0.53~0.63 mm/a，推断其为1605年琼山大地震的发震断裂。本研究取得的铺前−清澜断裂全新世活动的新证据，为国土空间规划和区域地震危险性评价提供了科学依据。Abstract: The Puqian-Qinglan fault, located in northern Hainan Province, is closely related to the judgment of the seismogenic structure of the Qiongshan M7.5 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 PuqianQinglan fault dislocates multiple marker strata, with the shallowest dislocation occurring in the silt layer of the Holocene 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 correlation, 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 M7.5 earthquake in 1605. The new evidence for the Holocene activity of the Puqian-Qinglan Fault obtained in this study provides a scientific basis for spatial land planning and regional seismic hazard assessment.
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[1] 陈恩民，黄咏茵. 1605年海南岛琼州大地震及其发震构造的初步探讨[J]. 地震地质，1979，1（4）：37−44. CHEN Enmin,HUANG Yongyin. Preliminary discussion on the 1605 Qiongzhou earthquake and its seismogenetic structure[J]. Seismology and Geology,1979,1（4）:37−44. [2] 徐起浩. 1605年琼州大地震陆陷成海和可能的海啸[J]. 海洋学报，2007，29（3）：146−156. XU Qihao. The land sank into the sea and possible tsunami by the great earthquake in Qiongzhou in China in 1605[J]. Acta Oceanologica Sinica,2007,29（3）:146−156. [3] 陈恩民，黄咏茵. 1605年海南岛琼州大地震的震害特征和发震构造研究[J]. 地震学报，1989，11（3）：319−331. CHEN Enmin,HUANG Yongyin. Characteristics of the seismic damage and analysis of the seismic structure of the 1605 great earthquake of Qiongzhou Hainan island[J]. Acta Seismologica Sinica,1989,11（3）:319−331. [4] 李志雄，赵文俊，刘光夏. 1605年琼山大地震深部构造和应力状态研究[J]. 华南地震，2006，26（1）：28−36. LI Zhixiong,ZHAO Wenjun,LIU Guangxia. A study on deep crust structures and stress situation of the 1605 Qiongshan strong earthquake[J]. South China Journal of Seismology,2006,26（1）:28−36. [5] 张新东，王晓山，沈繁銮，等. 由现今小震资料研究琼北地区区域应力场和发震构造[J]. 地震学报，2013，35（4）：451−460. ZHANG Xindong,WANG Xiaoshan,SHEN Fanluan,et al. The stress field and seismogenic structure in northern Hainan island based on current small earthquakes[J]. Acta Seismologica Sinica,2013,35（4）:451−460. [6] 徐晓枫，王惠琳，陈小敏. 海南岛及邻区地震精确定位及断裂构造分析[J]. 地震研究，2014，37（2）：216−221. XU Xiaofeng,WANG Huilin,CHEN Xiaomin. Analysis on accurate location of earthquakes and fault structure in Hainan island and its adjacent areas[J]. Journal of Seismological Research,2014,37（2）:216−221. [7] 汪一鹏. 关于“城市活断层探测与地震危险性评价工作大纲（试行）”的几点认识[J]. 地震地质，2004，26（4）：559−565. WANG Yipeng. Recognition of “the working guidelines for exploration and seismic risk assessment of active faults in urban areas （on trial）”[J]. Seismology and Geology,2004,26（4）:559−565. [8] 胡久常，白登海，王薇华，等. 琼州7.5级地震区深部电性异常及地震活动性研究[J]. 地震学报，2007，29（3）：258–264. HU Jiuchang,BAI Denghai,WANG Weihua,et al. Deep electrical anomaly in the M7.5 Qiongzhou earthquake region and its relation with future seismicity[J]. Acta Seismologica Sinica,2007,29（3）:258–264.
[9] 向宏发，方仲景，张晚霞，等. 北京平原区隐伏断裂晚第四纪活动性的初步研究[J]. 地震学报，1993，15（3）：385−388. XIANG Hongfa,FANG Zhongjing,ZHANG Wanxia,et al. Preliminary study of late Quaternary activities of buried faults in the Beijing plain area[J]. Acta Seismologica Sinica,1993,15（3）:385−388. [10] 向宏发. 隐伏活动构造探测研究的若干问题讨论[J]. 地震地质，2003，25（3）：460−466. XIANG Hongfa. Some problems in the exploration and research of buried active fault[J]. Seismology and Geology,2003,25（3）:460−466. [11] 柴炽章，孟广魁，杜鹏，等. 隐伏活动断层的多层次综合探测：以银川隐伏活动断层为例[J]. 地震地质，2006，28（4）：536−546. CHAI Chizhang,MENG Guangkui,DU Peng,et al. Comprehensive multi–level exploration of buried active fault:An example of Yinchuan buried active fault[J]. Seismology and Geology,2006,28（4）:536−546. [12] 邓起东. 城市活动断裂探测和地震危险性评价问题[J]. 地震地质，2002，24（4）：601−605. DENG Qidong. Exploration and seismic hazard assessment of active faults in urban areas[J]. Seismology and Geology,2002,24（4）:601−605. [13] 邓起东，徐锡伟，张先康，等. 城市活动断裂探测的方法和技术[J]. 地学前缘，2003，10（1）：93−104. DENG Qidong,XU Xiwei,ZHANG Xiankang,et al. Methods and techniques for surveying and prospecting active faults in urban areas[J]. Earth Science Frontiers,2003,10（1）:93−104. [14] 方盛明，张先康，刘保金，等. 探测大城市活断层的地球物理方法[J]. 地震地质，2002，24（4）：606−613. FANG Shengming,ZHANG Xiankang,LIU Baojin,et al. Geophysical methods for the exploration of urban active faults[J]. Seismology and Geology,2002,24（4）:606−613. [15] 雷启云，柴炽章，孟广魁，等. 隐伏活断层钻孔联合剖面对折定位方法[J]. 地震地质，2011，33（1）：45−55. LEI Qiyun,CHAI Chizhang,MENG Guangkui,et al. Method of locating buried active fault by composite drilling section doubling exploration[J]. Seismology and Geology,2011,33（1）:45−55. [16] 刘华国，李峰，贾启超. 基于钻探的马袅–铺前断裂西段活动性探讨[J]. 华南地震，2018，38（1）：47−53. LIU Huaguo,LI Feng,JIA Qichao. Activity discussion of the western segment of the Maniao–Puqian Fault revealed by drilling[J]. South China Journal of Seismology,2018,38（1）:47−53. [17] 王志成. 土氡测量在海口市活动断层探测中的初步应用[J]. 华南地震，2006，26（4）：61−66. WANG Zhicheng. Preliminary application of soil radon measurement method in active fault survey in Haikou City[J]. South China Journal of Seismology,2006,26（4）:61−66. [18] 徐锡伟，计凤桔，于贵华，等. 用钻孔地层剖面记录恢复古地震序列：河北夏垫断裂古地震研究[J]. 地震地质，2000，22（1）：9−19. XU Xiwei,JI Fengju,YU Guihua,et al. Reconstruction of Paleoearthquake sequence using stratigraphic records from drill logs:A study at the Xiadian Fault,Beijing[J]. Seismology and Geology,2000,22（1）:9−19.
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