岩石物理约束建模和地震导向钻井技术在深水盆地中的应用的分析.pdfVIP

岩石物理约束建模与地震导向钻井技术在深水 盆地中的应用研究 崔 杰，Sherman Yang，Nader Dutta （斯伦贝谢（中国）地球物理中心，北京 100015） 摘要：构建准确的地下地质模型是钻探成功的关键，基于常规的层析成像速度反演得出的速度模型有可能不是唯 一的，尤其是存在各向异性的情况，针对此问题本文应用了岩石物理约束的速度建模方法，创新点在于应用从速 度预测得到的孔隙压力做为约束来进行反复迭代，使得速度模型更加合理，将其用于偏移后不仅可以使得共成像 点道集拉平，还可以在没有井控的情况下使得速度场更具有物理和地质意义。同时我们将岩石物理约束的速度模 型用于地震导向钻井的钻前地质模型，然后利用钻井得到的实时数据更新地质模型，从而实时更新钻头前方的三 维成像及孔隙压力预测，有效地优化井眼轨迹和泥浆比重，避免地质灾害，降低钻井过程中的井涌和泥浆漏失的 风险。 关键词：岩石物理约束；速度建模；地震导向钻井 Rock Physics Guided Velocity Modeling and Its Application for Seismic Guided Drilling in Deep Water Basin CUI Jie, Sherman YANG, Nader DUTTA (Schlumberger Geosolutions, Beijing, 100015, China) Abstract: High accuracy earth model is a key for drilling success. Earth models solely based on tomography may be non-unique, especially in presence of anisotropy. Here we propose a new method, termed as rock physics guided velocity modeling. A novel feature of this technology is that it uses predicted pore pressure as a guide to improve the quality of earth model in an iterative manner. Thus, we produce a velocity model that not only flattens the CIP gathers but also limits the velocity field to its physically and geologically plausible range without well control. Then we can apply this new velocity modelling method to build the pre-drill model for Seismic Guided Drilling. Pre-drill model around the well is updated with real-time logs and checkshots (LWD, SVWD,Wireline),and then get the look ahead 3D imaging and pore pressure predication. The results can be are by drillers to make adjustments to the well trajectory, casing points, and/or possible sidetrack decisions. Keywords: rock physics guided, velocity model building, seismic guided drilling