基于叠前深度偏移的三相融合速度分析与复杂圈闭落实

克深三维地震区位于库车坳陷克拉苏构造带东部，其地表地形高陡，起伏剧烈，地下构造复杂，地震资料信噪比较低，叠前时间偏移处理后误差很大。为提高目的层成像质量，使断片接触关系更清楚，运用了叠前深度偏移处理。但受叠前深度偏移速度模型精度限制，利用叠前深度偏移确定的构造形态与实际存在一定差异。为了提高构造成图精度，提出了利用叠前深度偏移速度模型，将叠前深度偏移数据转换到时间域，即深时转换，同时开展岩相、地震相和应力相三相融合的速度分析，最终利用变速成图落实复杂圈闭。该方法继承了深度偏移资料归位较准确、三相融合速度场精度较高和变速成图技术成熟的优点，提高了圈闭落实精度。利用该成果部署的一批井位与实钻吻合程度显著提高，为克拉苏构造带山地三维地震区油气发现及整体评价勘探奠定了基础。

Petroleum Exploration Achievements and Future Targets of Tarim Basin

Ever since the foundation of Tarim Oilfield Company on April 10, 1989, great achievements have been obtained in 3 major fields: Kuqa foreland depression, carbonate rocks and clastics in the platform region with the cumulative proved oil and gas reserves amounting to 2.88 billion tons (equivalent). Tarim oilfield has become the major source area for the West-to-East natural gas transmission project and the third large oil and gas field in the mainland China. During the past 30 years of exploration practice, geological understandings about the foreland Kuqa depression, Southwest depression, carbonate rocks in the platform region and clastics in the platform region were continuously deepened, and the source rock, reservoir-cap rock assemblage, structure style, trap and reservoir model were identified for the 3 petroleum systems such as Kuqa depression, platform region and Southwest depression. The remaining exploration potentials of Tarim basin are enormous. The fine exploration should be carried out in the Kelasu tectonic belt of Kuqa depression, clastics in the western Tabei uplift, Ordovician Yijianfang formation in Tabei—Manxi area. The researches and exploration of Qiulitage tectonic belt in Kuqa depression, Jurassic series in the northern tectonic belt, Ordovician deep series in the platform region, Cambrian subsalt strata and piedmont area in the Southwest depression should be strengthened and the strategic breakthrough can be made