石油与天然气地质
石油與天然氣地質
석유여천연기지질
OIL & GAS GEOLOGY
2014年
2期
231-237
,共7页
张翔%田景春%杜本强%夏吉文%古娜%林小兵%邓飞涌%梁宇晨
張翔%田景春%杜本彊%夏吉文%古娜%林小兵%鄧飛湧%樑宇晨
장상%전경춘%두본강%하길문%고나%림소병%산비용%량우신
成岩作用%构造-岩性复合气藏%致密砂岩%须家河组%观音场地区%四川盆地
成巖作用%構造-巖性複閤氣藏%緻密砂巖%鬚傢河組%觀音場地區%四川盆地
성암작용%구조-암성복합기장%치밀사암%수가하조%관음장지구%사천분지
diagenisis%composite structural-lithologic reservoir%tight sandstone%Xujiahe Formation%Guanyinchang area%Sichuan Basin
蜀南观音场地区须家河组储层主要为一套三角洲平原分流河道砂体。对储层成岩作用的描述及致密化原因分析认为:沉积时水动力强弱决定了砂体储集性能的好坏,强烈的机械压实作用是原生孔隙大量损失的主要原因,成岩期石英次生加大是砂岩储层致密的关键因素。砂岩中石英次生加大边包裹体温度分布在82.5~125.1℃,推算致密化深度介于1725~2864 m,发生在燕山构造活动期间。根据研究区须家河组砂岩储层致密化过程与成藏运聚期次分析,认为:初次成藏期,砂岩储层未致密,天然气可以横向长距离运移;成藏高峰期前,砂岩储层已经致密,天然气不能横向长距离运移,以河道不整合面和高压开启的微裂缝作为运移通道;喜山期定型为现今的构造-岩性复合气藏,气藏受岩性、构造共同控制,非均质性强。
蜀南觀音場地區鬚傢河組儲層主要為一套三角洲平原分流河道砂體。對儲層成巖作用的描述及緻密化原因分析認為:沉積時水動力彊弱決定瞭砂體儲集性能的好壞,彊烈的機械壓實作用是原生孔隙大量損失的主要原因,成巖期石英次生加大是砂巖儲層緻密的關鍵因素。砂巖中石英次生加大邊包裹體溫度分佈在82.5~125.1℃,推算緻密化深度介于1725~2864 m,髮生在燕山構造活動期間。根據研究區鬚傢河組砂巖儲層緻密化過程與成藏運聚期次分析,認為:初次成藏期,砂巖儲層未緻密,天然氣可以橫嚮長距離運移;成藏高峰期前,砂巖儲層已經緻密,天然氣不能橫嚮長距離運移,以河道不整閤麵和高壓開啟的微裂縫作為運移通道;喜山期定型為現今的構造-巖性複閤氣藏,氣藏受巖性、構造共同控製,非均質性彊。
촉남관음장지구수가하조저층주요위일투삼각주평원분류하도사체。대저층성암작용적묘술급치밀화원인분석인위:침적시수동력강약결정료사체저집성능적호배,강렬적궤계압실작용시원생공극대량손실적주요원인,성암기석영차생가대시사암저층치밀적관건인소。사암중석영차생가대변포과체온도분포재82.5~125.1℃,추산치밀화심도개우1725~2864 m,발생재연산구조활동기간。근거연구구수가하조사암저층치밀화과정여성장운취기차분석,인위:초차성장기,사암저층미치밀,천연기가이횡향장거리운이;성장고봉기전,사암저층이경치밀,천연기불능횡향장거리운이,이하도불정합면화고압개계적미렬봉작위운이통도;희산기정형위현금적구조-암성복합기장,기장수암성、구조공동공제,비균질성강。
Tight sandstone reservoir of the Xujiahe Formation in Guanyinchang area mainly consists of delta plain distribu-tary channels sandbodies .Based on analyses of reservoir diagenesis and tightening ,detailed study shows that the hydrody-namic conditions during sedimentation determine the storage capacity of reservoirs .Strong compaction is the major factor causing the decrease of inter-particle primary porosity ,and quartz overgrowth in diagenetic stage is the key factor causing the tightening of reservoir .The temperatures of fluid inclusions in quartz overgrowth is between 82.5-125.1 ℃,accor-ding to which the tightening depth is estimated to be between 1 725-2 864 m.This depth interval corresponds to the pe-riod of Yanshan movement .According to analysis of the tightening process and hydrocarbon accumulation stages in the Xujiahe Formation sandstone reservoir ,the following understandings were obtained .The sandstone reservoir was not tight-ened at the initial phase of gas accumulation ,so gas could migrate long distance laterally .Before the peak gas accumula-tion,the sandstone reservoir had become tight ,thus the gas could not migrate laterally for a long distance ,instead,they migrated along the unconformity of channel and microfractures opened by high pressure .of the composite structural and lithologic gas reservoir got finalized during Himalayan epoch ,and the gas reservoir was controlled by both lithology and structures ,so their heterogeneity was strong .