澳大利亚苏拉特区块低煤阶煤层气有利区预测与高效开发策略  

Play fairway mapping and strategies for efficient production of low-rank coalbed methane in the Surat block,Australia

作　　者：何文渊 黄文松[2] 崔泽宏[2] 刘玲莉[2] 段利江[2] 赵一波 HE Wenyuan;HUANG Wensong;CUI Zehong;LIU Lingli;DUAN Lijiang;ZHAO Yibo(China National Oil and Gas Exploration and Development Company Ltd.,Beijing 100034,China;Research Institute of Petroleum Exploration&Development,PetroChina,Beijing 100083,China;China University of Geosciences(Beijing),Beijing 100083,China)

机构地区：[1]中国石油国际勘探开发有限公司,北京100034 [2]中国石油勘探开发研究院,北京100083 [3]中国地质大学(北京),北京100083

出　　处：《石油与天然气地质》2025年第1期31-46,共16页Oil & Gas Geology

基　　金：国家自然科学基金项目(92255302)。

摘　　要：澳大利亚苏拉特区块的煤层薄而多(平均厚度0.6 m),并与砂-泥岩频繁互层,导致煤层气赋存位置与富集规律难以预测。随着煤层气开发逐渐向深层拓展,开发部署时既要考虑煤层气富集情况,还要考虑地面工程的布局。为了实现苏拉特区块煤层气的规模效益开发,明确了研究区主力煤层气储层的基本特征,并通过分析研究区低煤阶煤层气气藏富集的主控因素,建立了基于煤层可动用厚度、含气量和渗透率3个核心参数的有利区综合评价体系,预测了煤层气有利区带。在此基础上,充分借鉴中国煤层气成功开发经验,形成了一系列针对研究区低煤阶煤层气的高效开发策略:①在煤层含气量预测方面,创新了一套基于煤相净/毛比概率趋势属性的煤相建模流程,建立了一套综合干燥无灰基含气量随埋深的变化趋势、测井数据和岩心测试数据的原煤基含气量预测流程;②在钻/完井方面,提出“直井+丛式定向井”的混合布井方案,并引入经济评价参数,优化了不同深度条件下的井间距和平台间距;③在排采方面,通过综合考虑生产动态数据和现场检泵结果,提出了一套直井螺杆泵失效分析的流程,并优化了斜井的内衬油管设计,并成功应用联合研发的新型遇水膨胀封隔器解决了生产中的出砂问题,提高排采效率;④在地面工程方面,提出基于地面-地下一体化理念的地面设施布局流程,并通过考虑单井开发的经济净现值产量(PV-EUR)优化掉低效井。通过这些技术策略,提高了项目的内部收益率,打开了苏拉特区块煤层气规模开发的局面。The Surat block in Australia exhibits numerous thin coal seams(average thickness:0.6 m)that are frequently interbedded with sandstones and mudstones,making it difficult to predict the occurrence locations and enrichment patterns of coalbed methane(CBM)in this block.With the progressive expansion toward deep CBM production,it is necessary to consider both CBM enrichment conditions and ground engineering layouts during deployment.To achieve large-scale commercial CBM production in the Surat block,we examine the essential characteristics of the major CBM reservoirs in the study area,and analyze the dominant factors governing the enrichment of low-rank CBM in these reservoirs,o which basis a comprehensive assessment system for play fairways based on three core parameters:producing interval thickness,gas content,and permeability is built.Using this assessment system,we map the play fairways of CBM.What’s more,a series of strategies for the efficient production of low-rank CBM in the study area are proposed while learning from China's successful experience in CBM production.For the prediction of gas content in coal seams,we introduce an innovative coal facies modeling process based on the probabilistic trend attribute of net-to-gross(NTG)ratios of coal phase,and a prediction process for in situ gas content in coal seams that integrates the trend of dry,ash-free gas content variation with burial depth,log data,and the data of core tests.Regarding well drilling and completion,a hybrid well placement scheme that combines vertical wells with cluster directional wells is proposed,and economic assessment parameters are adopted to optimize vertical-well spacing and the drilling pad spacing of cluster wells for CBM reservoirs at varying depths.In terms of gas production,comprehensively considering the production performance data and field pump inspection results,we propose a failure analysis process for screw pumps in vertical wells and optimize the design of lined oil tubing for deviated wells.Furthermore,the challenge of s

关 键 词：低煤阶煤层气 开发实施策略 有利区预测 煤层气含气量 Wallon亚群 中侏罗统 苏拉特区块 澳大利亚 

分 类 号：TE132.2[石油与天然气工程—油气勘探]