逆时偏移技术在碳酸盐岩缝洞体成像中的应用  

Application of reverse-time migration technology in imaging of fractures and cavities in carbonate reservoirs

作　　者：高厚强[1] 徐颖[1] 邵文潮 穆洁[1] 蒋波[1] 陈哲[1] 

机构地区：[1]中国石化石油物探技术研究院

出　　处：《中国石油勘探》2017年第1期99-105,共7页China Petroleum Exploration

基　　金：国家科技重大专项"碳酸盐岩缝洞型储层预测技术方法应用"(2011ZX05049-001-002-004)

摘　　要：塔里木盆地奥陶系碳酸盐岩储层埋藏深度大,非均质性强,缝洞型储层广泛发育;而且该地区火成岩广泛发育,火成岩厚度和形状变化大,速度变化快,对下伏地层成像产生畸变,对低幅构造厚度刻画也带来一定影响。逆时偏移(RTM)技术具有适应速度横向变化、成像精度高等优点,利用低频速度场建立及更新、高分辨率速度建模、分层网格层析迭代等高精度速度建模关键技术,反演出塔里木盆地精确的背景速度场,进行逆时偏移成像,可有效消除火成岩引起的假构造,提高缝洞成像精度,准确识别"串珠"边界及空间位置。In the Tarim Basin, the Ordovician carbonate reservoirs are deeply buried with strong heterogeneity, and fracture-cavity reservoirs are widely distributed. Moreover, igneous rocks are extensively developed with thickness and shape greatly varying and velocity quickly changing. Subsequently, the images of underlying formations are often distorted, and the thickness characterization of low-relief structures is negatively influenced. Reverse-time migration（RTM） technology is characterized by adaptability to lateral velocity change and high imaging precision. With some key high-precision velocity modeling techniques（e.g. low-frequency velocity field establishment and update, highresolution velocity modeling, and hierarchical grid tomographic iteration）, the background velocity field of the Tarim Basin is accurately inverted for reverse-time migration imaging. In this way, the pseudo-structures resulted from igneous rocks can be effectively eliminated and fracture-cavity imaging precision can be improved. As a result, the ＂paternoster＂ boundary and its spatial location can be accurately distinguished.

关 键 词：碳酸盐岩储层 火成岩 横向变速 高精度建模 逆时偏移 

分 类 号：P631.4[天文地球—地质矿产勘探]