A simplified 2D petrophysical model for regular polygon pores
LIU Zhishui1, BAO Qianzong1, LIU Junzhou2, SHI Lei2
1. College of Geological Engineering and Geoma-tics, Chang'an University, Xi'an, Shaanxi 710054, China; 2. Research Institute of Petroleum Exploration and Development, SINOPEC, Beijing 100083, China
Abstract：It is common for petrophysical modeling to make pores in rock equivalent to two-dimensional (2D) ellipses or three-dimensional (3D) ellipsoids,while the modeling of other pore types is rarely studied. The Kachanove 2D model is a classical petrophysical model for regular polygon pores,which involves multiple pore shape factors and can only characterize a few pore shapes. It can hardly be combined with mathematical algorithms such as adaptive algorithms. Considering this,we introduce a single pore shape factor g to act as the equivalent of multiple shape factors in the above model. In this way,a simplified 2D petrophysical model for regular polygon pores is obtained,and the theoretical value range of g is given. The numerical forward modeling of sandy mudstone illustrates seve-ral conclusions:When g is greater, the elastic mo-dulus is smaller,and thus when g is closer to 1, the elastic modulus is greater. Moreover,the decline rate of the elastic modulus decreases with the growth of g,and the change rate of the elastic mo-dulus becomes smaller as the porosity declines. In practical applications,the range of g does not reach infinity. The proposed model is applied in laboratory tests on sandy mudstone and actual logging data,and the results show that the proposed model in this paper can achieve good performance in applications.
刘致水, 包乾宗, 刘俊州, 时磊. 一种简化的二维规则多边形孔隙岩石物理模型[J]. 石油地球物理勘探, 2022, 57(1): 140-148.
LIU Zhishui, BAO Qianzong, LIU Junzhou, SHI Lei. A simplified 2D petrophysical model for regular polygon pores. Oil Geophysical Prospecting, 2022, 57(1): 140-148.
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