【摘要】 深层致密砂岩气藏具有埋藏深、物性差、产量低的特点,但勘探潜力大。有利烃源岩发育区控制天然气的平面分布,深层致密砂岩储层中发育的"有效储渗体"是天然气富集、高产的关键。"有效储渗体"的发育受构造、沉积相和成岩相3种因素控制。有效孔隙控制了天然气的分布,裂缝控制了天然气的高产。四川盆地川西坳陷须家河组气藏具有超深、超高压、超致密等特征,储层和高产富集带预测难度大。利用三维三分量地震勘探技术,可有效解决优质储层预测、裂缝检测、含气性识别等关键问题。该技术在川西坳陷深层致密砂岩气藏勘探中应用取得了显著效果,使须家河组二段钻井成功率从15%提高到89%,高产井命中率从9%提高到67%,探明天然气地质储量1211×108m3,实现了川西致密气田的高效勘探。更多还原

【Abstract】 Deep tight gas reservoirs are characterized by deep burial depth,poor reservoir quality and low production rate,but large exploration potentials.Distribution of favorable source rocks controls the planar distribution of gas reservoirs,and "effective reservoirs" in deep tight sands are the key to gas accumulation and production.Their development is under the control of structure,sedimentary facies and diagenetic facies.Effective porosity controls gas distribution,while fracture controls gas production rate.The gas reservoirs in the Xujiahe Formation in the western Sichuan depression feature in ultra-deep,superpressure and extra-tight,challenging prediction of reservoirs and sweet points.The 3D-3C seismic exploration technology is capable of solving such problems as quality reservoir prediction,fracture detection and gas potential identification.It has been successfully applied to exploration of the deep tight gas reservoirs in the western Sichuan depression.The success rate of exploratory drilling in the second member of the Xujiahe Formation is raised from 15% to 89%,and high yield well ratio increases from 9% to 67% ,and the discovered gas in place is 121.1 BCM.High efficiency exploration of tight sand gas is realized in the western Sichuan depression.更多还原