摘要
乐山—龙女寺加里东古隆起形成时间早,延续时间长,隆起幅度大,分布面积广,是下古生界储层聚集油气成藏的最有利场所。下寒武统筇竹寺组是目前公认的一套优质有效的烃源岩。有机质丰度高,类型好,沉积厚度大,生烃强度大,能为形成大中型油气藏提供充足的烃源。洗象池群存在十分有利于储层发育的沉积相带。如,在潮坪相区和台内滩相区相对发育的颗粒白云岩。古岩溶比较发育,容易形成孔洞层。古隆起带核部和古斜坡带一直处于古构造演化的高部位,强烈的风化壳岩溶和埋藏岩溶作用,是下古生界储层聚集油气藏的最有利场所。重视古隆起核部及上斜坡区带中上寒武统的油气勘探。
Leshan-Longnvshi palaeo-uplift in Sichuan Basin formed during Caledonian orogeny and is the most favorable place for Lower Mesozoic oil and gas accumulation to form a reservoir.The uplift is characterized by early formation era,long perdurability,large uplift extension and wide distribution.At present Lower Cambrian Qingzhusi Formation is considered as high-quality and effective source rocks,which are featured by high-abundance organic matter,good type,large depositional thickness,strong hydrocarbon-generated capacity and may provide sufficient sources for forming a medium-and large-scale reservoir.There exists sedimentary facies which is most favorable for reservoir development in Xixiangchi Member.For example,the more developed grain dolomite both in tidal-flat facies zone and interplatform beach facies zone.In these zones,palaeokarst is well developed to form vuggy intervals.Both the center of palaeo-uplift and palaeo-slope,situated at the highs of palaeo-structure,underwent strong weathering and burial karstification and become the most favorable place for Lower Mesozoic oil and gas accumulation to form the reservoir.
出处
《天然气勘探与开发》
2006年第4期4-8,共5页
Natural Gas Exploration and Development
关键词
乐山龙女寺
古隆起
中上寒武统
烃源岩
台内浅滩相
Leshan-Longnvshi papaeo-uplift,middle and upper Cambrian,source rock,interplatform shallow beach
