Application of geological model dynamic updating method in Guanjiapu Oilfield, Dagang

Abstract

Through building 3D geological models in different drilling time according to the logging while drilling (LWD) data and by updating the previous geological models, the dynamic updating of geological model could enable the acquisition of the spatial distribution of reservoir effectively and find the structural and occurrence changes instantly, so as to modify the former designed borehole track and adjust the drilling track by geosteering, and drill the oil layers in the best way. It can improve the effectiveness of horizontal interval and the drilling benefit. Combined with well logging, geological data and seismic data as well as the LWD data, this method was applied to the drilling of the Guanjiapu Oilfield, and the geological conditions were constrained by the multistage modeling method, to update and improve the Gamma Ray (GR), porosity and permeability models and the accuracy of reservoir random models, especially the sandstone distribution model to ensure the accuracy and reliability of the model. The drilling of Well Zh8-H has shown that the geosteering drilling capability was obviously improved in light of providing accurate geological model timely. 摘要: 地质模型动态更新依据随钻测井资料及时更新先期建立的地质模型，得到钻井不同时刻的三维地质模型，实时有效地了解储集层空间展布，及时发现其构造、产状等的变化，从而对原有设计井眼轨迹加以修正，有效地调整钻井前进轨迹，发挥地质导向作用，直至以最佳方式穿过油层，最终达到提高水平段有效率和钻井总体效益的目的。把地质模型动态更新方法应用于关家堡油田水平井钻井过程中，结合测井、地质和地震等资料，并把随钻资料加入到地质模型中，采用多步建模的方法进行地质条件约束，更新并完善GR、孔隙度、渗透率等模型，提高了储集层随机建模精度，特别是砂体分布模型的精度，保证了模型的准确性和可靠性。Zh8-H井钻井实践表明，由于及时地提供了较为准确的地质模型，明显地提高了水平井钻遇油层的能力。 Key words: litho-structural reservoir, geological modeling, logging-while-drilling, geological model updating, multistage modeling, horizontal well, Guanjiapu Oilfield