埕北30潜山带太古界储层特征及其影响因素

Characters and influence factors on Archeozoic reservoir in the Chengbei 30 buried hills

通过岩心观察、薄片鉴定、物性分析、扫描电镜观察等技术手段 ,研究了埕北 3 0潜山带太古界储层的主要岩石类型、储集空间类型、物性特征和影响因素。研究结果表明 ,埕北 3 0潜山带太古界 4类结晶岩中 ,以碎裂状混合岩化黑云母二长片麻岩裂缝最为发育 ,物性最好 ,产能最高 ,在Pt_Art不整合面以下约 2 5 0m范围内一般均为有效储层 ,储层厚度为 10 0～ 15 0m。埕北 3 0潜山带太古界储层主要是裂隙缝和微裂隙含油 ,溶蚀孔隙 (包括晶溶孔、晶间孔、晶模孔 )和晶间微孔隙也有一定的储集意义。影响研究区太古界结晶岩储集性的因素有岩性、断裂活动引起的碎裂作用、岩浆侵入引起的混合岩化作用、古表生风化作用和深层溶解作用等。

The main types of rocks and reservoir spaces,characters and influence factors of Archeozoic reservoir in the Chengbei 30 buried hills were studied by means of observation on cores,electronic scanning and thin-section analysis.There are four types of crystalling rocks in Archeozoic of the Chengbei 30 buried hills.The most developed fractures are in cataclastic metamorphic migrated biotite feldspar gneiss.The physical properties of those fractures are the best,and their productivities are the highest.The reservoirs under the unconformity between Art and Pt around 250 meters are the valuable ones,and the thickness of reservoirs is in the range of 100 meters to 150 meters.The fractures and micro-cracks are the main reservoir spaces for oil accumulation in the Archeozoic reservoir of the Chengbei 30 buried hills.The dissolving pores,including crystal dissolving pores,inter-crystal dissolving pores and crystal casting pores,and micro?-inter-crystal pores are the available reservoir spaces.The main influence factors on reservoir accumulation in Archeozoic reservoir of the Chengbei 30 buried hills include the lithology,cataclasis caused by faulting,magmatization caused by magmatite intrusion,weathering and dissolution in the deep formation.