以JZ25-1S太古宇变质岩潜山为研究对象,综合利用岩心、测井、录井、生产测试等资料,进行了古风化壳结构研究.通过地质背景分析、岩心观察、测井分析以及对典型井元素地球化学特征研究,认为该风化壳结构中整体缺失风化黏土层,只发育半风化壳(半风化岩石),而半风化壳又可以划分为半风化壳上段和半风化壳下段两部分;潜山风化壳储层物性特征主要受到半风化壳结构的控制,半风化壳上段和下段储层发育所受的影响因素不同,储集物性也就存在差异;由于半风化壳上段与下段储集物性的差异,导致了生产测试产能的差异,各井半风化壳上段试油绝对产量受储层渗透性变化的影响呈现较大的差异,单井绝对产量0～ 110 m3/d,平均34m3/d,半风化壳下段试油绝对产量差异不大,单井绝对产量普遍大于300 m3/d.%Taking JZ25-1S Archaean metamorphic-rock buried hill as the object of studies and comprehensively integrating the data of cores, well logging, mud logging, production test and so on, the in-depth studies of the ancient weathered crust structure have been conducted. By means of the analysis of the geological background, core observation, logging analysis and the researches on the geochemical characteristics of the elements in the typical wells, the ancient weathered crust is found complete miss of weathered clay rocks, the semi-weathered crust, namely semi-weathered rocks are only developed, and moreover the semi-weathered crust can be divided into two parts; upper one and lower on; the reservoir physical properties of the crust are mainly controlled by the structure of semi-weathered crust. The upper and the lower are impacted by different factors in the reservoir development, thus the reservoir physical properties are also different; the differences stated above in the two parts in turn lead to the productivity differential in the production test. The absolute tested oil productions of the upper semi-weathered crust in each well are influenced by the reservoir permeabilities and there are huge contrast among them; 0-110 m3/d, and the average yield is 34 mVd; those in the lower part are just on the contrary: the productions are generally higher than 300 m3/d.
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