摘要
松辽盆地南部长岭断陷登娄库组致密砂岩地层陆续发现了新的天然气区带,显示出巨大的勘探开发前景。利用大量岩心描述及分析化验资料,对登娄库组致密砂岩储层发育的控制因素进行了研究。对比研究认为,埋藏史是控制地区间储层物性差异的主要因素;而在埋藏史相近的地区,沉积微相是控制储层发育的主要因素。沉积分异过程造成不同微相储层岩石学性质的分异,而不同岩石相在成岩作用发生不同孔隙演化过程,其机制为:粒度粗、泥质少的砂岩,在压实过程中趋向于保留更多的原生孔隙,为溶蚀过程提供流体通道,导致溶蚀孔更发育,物性最好;含泥质砂岩中,泥质杂基在压实过程中强烈形变,充填孔喉,降低了物性,特别是降低了渗透率;与泥岩接触的砂岩,极易发生早期碳酸盐胶结,大幅降低了储层孔隙度。根据以上分析认为,心滩中下部及辫状河道中部砂岩最利于形成优质储层。通过对孔隙演化过程的模拟,定量印证了以上观点。
Newly discovered natural gas zones in tight gas sandstone strata of the Denglouku Formation in lower Cretaceous strata of the Changling Faulted Depression,southern Songliao Basin show great prospecting potential.By analyzing large amounts of core data and observing rock slices,we conclude that the controlling factors of reservoirs are as follows.The burial history largely decides the difference of rock properties between the four gas fields.In one single field,sedimentary facies is the key factor controlling reservoir properties.From the perspective of lithofacies,we find that different lithofacies which evolved from different microfacies have different influences on pore evolution and reservoir formation.Coarse-grained sands with little mud,which tend to preserve more primary pores and form large amounts of dissolution pores,are mostly possible to form favorable reservoirs.Sandstones with mud tend to lose more permeability during compaction.Sandstones which have direct contact with the mudstones tend to form calcite cement in the early stage of diagenesis and largely reduce the porosity.We conclude that the sandstones which formed in the middle and lower parts of channel bars,and others that formed in the middle parts of river channels,are most likely to form favorable reservoirs.Simulation of pore evolution processes in different gas fields and different lithofacies support our opinions about the controlling factors on reservoir formation.
出处
《地质科技情报》
CAS
CSCD
北大核心
2014年第4期72-80,共9页
Geological Science and Technology Information
基金
国家重大油气科技专项(2011ZX05015)
关键词
致密砂岩
登娄库组
岩石相
孔隙演化
tight gas sands
Denglouku Formation
lithofacies
pore evolution
作者简介
李易隆（1986-），男，现正攻读石油地质学博士学位，主要从事致密砂岩储层地质学研究工作。E—mail：syd19861113@163．com
通信作者：何东博（1972-），男，高级工程师，主要从事天然气开发地质和开发方案研究工作。E—mail：311@Petrochina．com．cn
