陳清華+李敏
摘 要:儲層細(xì)分對比存在的問題主要表現(xiàn)為兩個方面:一是儲層細(xì)分對比的結(jié)果往往是巖性單元,多不具等時性;二是儲層細(xì)分對比的結(jié)果仍不夠精細(xì),不能滿足高含水階段剩余油挖潛的需要。其根本原因是對層、地層結(jié)構(gòu)認(rèn)識的局限性。儲層細(xì)分對比以傳統(tǒng)地層學(xué)理論為指導(dǎo),認(rèn)為層、地層結(jié)構(gòu)符合“層狀”模式,即地層是全區(qū)分布、近于水平、相互平行的,并且層與層水平疊置。然而,層序地層學(xué)等突破了傳統(tǒng)地層學(xué)對層、地層結(jié)構(gòu)的認(rèn)識,認(rèn)為地層不一定全區(qū)分布、不一定水平、不一定相互平行;層的空間位置變化大,相互間可呈超覆、退覆等疊置特點(diǎn)。構(gòu)型要素分析法更細(xì)致地揭示了儲層結(jié)構(gòu)特征,認(rèn)為原來劃分的層是復(fù)合體,需進(jìn)一步細(xì)分。通過層次界面劃分,復(fù)合體可以被細(xì)分成一系列形態(tài)各異、分布復(fù)雜的構(gòu)型單元。從問題根源入手提出相應(yīng)對策,解決儲層細(xì)分對比存在的問題需要以沉積學(xué)、層序地層學(xué)、地震地層學(xué)等理論為指導(dǎo),運(yùn)用構(gòu)型要素分析法進(jìn)行層次界面劃分。
關(guān)鍵詞:儲層;細(xì)分對比;地層結(jié)構(gòu);構(gòu)型要素分析法;層次界面;等時性;精度;東辛油田
中圖分類號:P618.130.2+1;TE122.2 文獻(xiàn)標(biāo)志碼:A
文章編號:1672-6561(2016)05-0649-11
Abstract: Problems in the reservoir subdivision and correlation mainly display in two aspects: one is that the comparison results are usually lithologic units, which are often not isochronous; another one is that the accuracy of comparison result is not enough, which can not meet the needs of tapping the remaining oil in high water cut stage. The basic reasons are the limitation of the understanding of layer, stratum and the reservoir structures. Based on the traditional stratigraphic theories, the reservoir subdivision and correlation show that the layer and stratum structures accord with the “l(fā)ayer” mode, the layer distributes over the whole area, closing to the level and paralleling to each other, and the layers are stacked horizontally. However, the sequence stratigraphy, which breaks through the understanding of traditional stratigraphy, believes that the layer does not distribute over the whole area necessarily, not close to the level necessarily and not parallel to each other necessarily. The spatial position of layer varies greatly, and the superimposed relationships between layers can be overlap or offlap. Architectural-element analysis is more detailed to reveal the structural characteristics of the reservoir. The layer divided originally is a complex, which should be further divided hierarchically. Based on hierarchical interface division, the complex can be subdivided into a series of architecture units with different shapes and complex distribution. Beginning with the basic reason of problems, the corresponding countermeasure is proposed that taking the theories of sedimentology, sequence stratigraphy and seismic stratigraphy as guidance, the hierarchical interfaces are divided by the means of architectural-element analysis.
Key words: reservoir; subdivision and correlation; stratum structure; architectural-element analysis; hierarchical interface; isochronism; accuracy; Dongxin oilfield
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