基于倾角导向梯度能量熵的断层检测方法  

Fault identification based on dip-oriented gradientenergy-entropy coherence estimation

作　　者：彭达 肖富森[1] 冉崎 王跃祥 陈康 PENG Da;XIAO Fusen;RAN Qi;WANG Yuexiang;CHEN Kang(Research Institute of Exploration and Development ,Southwest Oil & Gas Field Company, PetroChina, Chengdu, Sichuan 610041, China;Post-Doctoral Mobile Station, Southwest Petroleum University, Chengdu, Sichuan 610500, China)

机构地区：[1]中国石油西南油气田公司勘探开发研究院,四川成都610041 [2]西南石油大学博士后科研流动站,四川成都610500

出　　处：《石油地球物理勘探》2019年第1期191-197,I0008,共8页Oil Geophysical Prospecting

基　　金："十三.五"国家科技重大专项"四川盆地大型碳酸盐岩气田开发示范工程"(2016ZX05052);中国石油天然气股份有限公司重大科技专项"西南油气田天然气上产300亿m3关键技术研究与应用"(2016E-0604)联合资助

摘　　要：断层解释是三维地震数据精细构造解释的关键。三维不连续性地震几何属性分析技术的发展,为断层等不连续性地质边界的检测和识别提供了极大的便利。针对传统地震几何属性对随机噪声较为敏感,用于检测和识别微小断层效果不好这一现实问题,提出了一种基于倾角导向梯度能量熵的相干分析方法。首先利用梯度结构张量获取倾角信息,然后通过构建梯度相关矩阵计算局部地震数据的梯度能量熵值。高能量熵值代表数据的连续性很差,低能量熵值代表数据的连续性很好,因此可以利用能量熵值刻画三维地震数据的不连续性空间结构信息。理论模型和实际数据测试表明,新方法不仅抗噪能力较强,而且对断层等不连续性边界的检测效果比超级地震道第一代相干体(ST-C1)、超级地震道第三代相干体(ST-C3)和局部结构熵相干体(LSE)都好,可以有效地用于三维断层及其他地质边界的地震解释。Locating small-scale strata discontinuities is one of the most challenging tasks, and these subtle geological features are significant since they are often associated with subsurface petroleum traps. Subtle faults, fractures, unconformities, reef textures, channel boundaries, thin-bed boundaries, and other structural and stratigraphic discontinuities have subtle geologic edges which may provide lateral variation on seismic data. Among different available geophysical techniques, 3-D seismic discontinuity attributes are effective tools for highlighting discontinuities on seismic data. Conventional seismic discontinuity attributes are sensitive to noise and are not appropriate for detecting smallscale discontinuities. Thus, we propose a dip-oriented gradient-energy-entropy ( DOGEE ) coherence to detect subtle faults and structural features. The DOGEE coherence estimation method uses gradient structure tensor (GST) algorithm to obtain local dip information and construct a gradient correlation matrix to calculate gradient energy-entropy. The proposed DOGEE coherence is robust to noise, and also improves the clarity of fault edges. It is effective for small-scale discontinuity characterization and interpretation.

关 键 词：倾角导向 梯度结构张量 能量熵 断层检测 

分 类 号：P631[天文地球—地质矿产勘探]