A calculation method of the stimulated reservoir volume based on octree and its engineering application
LIU Xing1，2，JIN Yan1，2，LIN Botao1，2，LIN Changqing3，XIE Lin3
(1. College of Petroleum Engineering，China University of Petroleum(Beijing)，Beijing 102249，China；
2. State Key Laboratory of Petroleum Resources and Prospecting，China University of Petroleum(Beijing)，Beijing 102249，China；3. Research Institute of Petroleum Exploration and Development of Qinghai Oilfield Company，Jiuquan，Gansu 736200，China)
Abstract：There exists a large error in conventional stimulated reservoir volume (SRV) calculation method which adopts relatively regular shapes to build 3D envelop. An integrated methodology that utilizes the octree method to generate irregular tree mesh structure according to the density of microseismic events was presented，in which the stimulated reservoir volume is obtained by summing up the volumes of non-empty nodes in the tree structure. The method was validated by analog events generated by Monte Carlo simulation and application of eighteen wells of Kunbei oilfield. It was found that the octree method can be used to envelop the event cloud perfectly and eliminate effectively enough the error of unresponsive zones during microseismic monitoring. The octree method fully considers the impact of event density on SRV calculation in different monitoring areas and determines hierarchies of tree structure according to local event density. Hence，the calculation result conforms to engineering knowledge. Engineering applications show that the method has a high computational efficiency for large scale microseismic data，and that the calculated SRVs are consisted with the daily liquid production of 18 wells in Kunbei oilfield. Compared with the conventional approach，the developed method provides a more reliable quantitative index for hydraulic fracturing evaluation.
刘 星1，2，金 衍1，2，林伯韬1，2，林长庆3，谢 琳3. 基于八叉树的储层改造体积计算方法及工程应用[J]. 岩石力学与工程学报, 2019, 38(5): 948-955.
LIU Xing1，2，JIN Yan1，2，LIN Botao1，2，LIN Changqing3，XIE Lin3. A calculation method of the stimulated reservoir volume based on octree and its engineering application. , 2019, 38(5): 948-955.
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2019, Vol. 38 
