基于“层序矢量滑距”的生长断层活动强度定量表征——以珠江口盆地番禺低隆起M区为例  

Quantitative characterization of syndepositional fault activity intensity with the sequence vector slip distance:An example in Panyu Low-uplift,Pearl River Mouth Basin

作　　者：刘勇[1] 都小芳 胡鹏 李熙盛 霍守东 徐海 Liu Yong;Du Xiaofang;Hu Peng;Li Xisheng;Huo Shoudong;Xu Hai(Urumqi Branch,GRI,BOP Inc.,CNPC,Urumqi,Xinjiang 830016,China;Zhongneng Power-Technology Development Company Limited,Beijing 100034,China;Laboratory of Marine Geology and Hydrology,Guodian New Energy Technology Research Institute,Beijing 102209,China;Shenzhen Branch,CNOOC,Shenzhen,Guangdong 518054,China;Key Laboratory of Petroleum Resources,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;Petroleum Exploration and Production Research Institute,SINOPEC,Beijing 100871,China)

机构地区：[1]中国石油东方地球物理公司研究院乌鲁木齐分院,新疆乌鲁木齐830016 [2]中能电力科技开发有限公司,北京100034 [3]国电新能源技术研究院海洋地质和水文研究室,北京102209 [4]中海石油(中国)有限公司深圳分公司,广东深圳518054 [5]中国科学院地质与地球物理所油气资源研究重点实验室,北京100029 [6]中国石化石油勘探开发研究院,北京100871

出　　处：《石油地球物理勘探》2018年第6期1256-1262,I0006,共8页Oil Geophysical Prospecting

基　　金："十三.五"国家科技重大专项"南大西洋两岸重点盆地油气勘探开发关键技术"(2016ZX05033-002);中科院A类战略性先导科技专项"智能导钻技术装备体系与相关理论研究"(XDA1404031)联合资助

摘　　要：传统二维标量对于单一断层定性和半定量的描述方式不能全面、准确地反映断裂系统活动强度与时空差异性。为了研究弱张扭性环境下同沉积断裂系统活动强度与时空差异性及其对古地貌的控制作用,本文首次提出了"层序矢量滑距"的概念与计算方法,依据高频层序界面定量计算构造幕内断裂系统空间展布与活动性质。以珠江口盆地番禺低隆起区珠江组下段为例,利用三维地震资料识别四组同沉积断裂系统和六个四级层序界面,以此求取各层序界面处各断裂系统的累计活动量——"总矢量滑距";同时,运用多重互相关算法对不同断裂系统在各层序界面处的断点进行空间定位,采用空间匹配求差运算,获取不同断裂系统在高频层序边界"矢量滑距"的增量,即单一层序发育时期断裂系统的活动量——"层序矢量滑距",实现对断裂活动强度的定量表征。结果表明:番禺低隆起区珠江组下段断裂系统活动强度整体呈现强—弱—强的变化趋势,古地貌变化受控于四组断裂系统,由早期的北高南低逐渐转变为东北高西南低。"层序矢量滑距"表征方法可以定量表征构造幕内"张性或弱扭张性"断裂的活动情况。Conventional 2D scalar methoas cannot comspacial difference of syndepositional fault systems under weak torsional environment and its control on paleo-geomorphology,the concept and calcula- tion method of the sequence vector slip distance (SVSD)are proposed in this paper.According to the high-frequency sequence interfaees,the spatial distribution and activity properties of fracture systems within the intramural tectonic activity are quantitatively calculated.In the lower part of Zhujiang Formation,Panyu Low-uplift,the Pearl River Mouth Basin,4sets of syndepositional fault systems and six 4th sequence boundaries are identified based on 3D seismic data.Then the cumulative activity of each fracture system at each sequence interface (total vector slip distance)are calculated. At the same time,multiple cross-correlation algorithms are used to spatially locate the breakpoints of different fracture systems at each sequence interface.With subtraction difference in space,the SVSD increment of the boundaries is obtained,that is the activity increment of the fracture systems in the single-sequence development period.Finally quantitative characterization of syndepositional fault activity intensity in different periods is achieved.The results show that the activity intensity of the fault systems in study area has a strongweak-strong trend,and the paleo-geomorphology controlled by four groups of the fault systems gradually changed from the early north high south low to the late northeast high southwest low.The proposed approach can effectively quantify the activity of "tension or weak torsion"fracture systems.

关 键 词：层序矢量滑距 同沉积断裂系统 定量表征 珠江口盆地 番禺低隆起 

分 类 号：P631[天文地球—地质矿产勘探]