广东珠海地区三灶断裂带早白垩世以来多期活动、古应力特征及动力学背景  

Multi-stage Activity,Paleo-stress Field and Dynamic Background of the Sanzao Fault Zone Since Early Cretaceous in the Zhuhai Area,Guangdong Province

作　　者：王令占 李响 吴俊 贾小辉 王晶 张宗言 金巍 徐大良 WANG Ling-Zhan;LI Xiang;WU Jun;JIA Xiao-Hui;WANG Jing;ZHANG Zong-Yan;JIN Wei;XU Da-Liang(Wuhan Center,China Geological Survey(Geosciences Innovation Center of Central South China),Wuhan 430205,Hubei,China)

机构地区：[1]中国地质调查局武汉地质调查中心(中南地质科技创新中心),湖北武汉430205

出　　处：《华南地质》2024年第2期323-342,共20页South China Geology

基　　金：中国地质调查局项目(DD20243437、DD20230204、DD20240038);珠海市城市地质调查(含信息化)项目(MZCD-2201-008)。

摘　　要：广东珠海地区三灶断裂带为莲花山断裂带的南西延伸段,其空间分布、变形特征及构造演化对认识华南东南部中新生代的构造演化过程具有重要意义。本文通过活动断裂填图、构造解析、地球物理勘探和地质钻探等手段,查明了三灶断裂带的空间分布以及不同期次变形的几何学与运动学特征。基于新获得的断层面与擦痕矢量数据反演了不同变形期次应力场及方向,结合区域大地构造演化历史,提出三灶断裂带早白垩世以来经历了五期古构造应力场作用,表现为多阶段不同方向的挤压和伸展过程,分别响应了晚中生代以来的一系列构造事件,Ⅰ期NW-SE向伸展(D_(1))可能记录了早白垩世初期区域地壳伸展;Ⅱ期NW-SE向挤压(D_(2))可能与早白垩世末期-晚白垩世早期造成华南地区断陷盆地反转及长乐南澳断裂带变形变质的挤压事件有关;Ⅲ期近SN向挤压(D_(3))可能与形成晚白垩世与古近纪地层之间区域性不整合的挤压事件有关;Ⅳ期近EW向挤压(D_(4))可能受控于渐新世-中新世南海洋盆的扩张;Ⅴ期NW-SE向伸展(D_(5))可能与上新世-第四纪菲律宾海板块的向西持续俯冲有关。The Sanzao fault zone in the Zhuhai area,Guangdong Province is the southwest extension of the Lianhuashan fault zone,and its spatial distribution,deformation characteristics and tectonic evolution are of great significance for understanding the tectonic processes of the Mesozoic and Cenozoic in southeastern South China.The spatial distribution of the Sanzao fault zone,the geometric and kinematic characteristics of different deformation stages were identified,through active fault mapping,detailed tectonic analysis,geophysical exploration and drilling.The stress field and their direction in different periods were inverted,based on the newly identified fault planes and slickensides data.Furthermore,combined with the regional tectonic evolution,it is regarded that the Sanzao fault zone was influenced by five phases of paleo-tectonic stress field since the early Cretaceous,characterized by multi-stage compression or extension in different directions.These phases responds to a series of regional tectonic events since the late Mesozoic respectively.Phase ⅠNW-SE extension(D_(1)) may record the regional crustal extension during the early Cretaceous.Phase ⅡNW-SE compression(D_(2)) may be related to the compression events that caused the reversed faulted basins in South China and deformation and metamorphism of Changle-Nanao fault zone during the late early Cretaceous to early late Cretaceous.Phase Ⅲ nearly SN compression(D_(3)) may be related to the compression events which produced the regional unconformity between the Late Cretaceous and Paleogene strata.PhaseⅣ nearly EW compression(D_(4)) may be controlled by the expansion of the South China Sea oceanic basin between the Oligocene and Miocene.Phase Ⅴ NW-SE extension(D_(5)) may be related to the sustained westward subduction of the Philippine Sea Plate from the Pliocene to Quaternary.

关 键 词：三灶断裂带 多期活动 古应力 早白垩世 广东珠海 

分 类 号：P542.3[天文地球—构造地质学]