录井大数据在水平井开发区潜力评价中的应用——以大牛地气田D 8-D 10井区为例

Application of mud logging big data in potential evaluation of horizontal well development zones:A case study of wellblock D 8-D 10 in Daniudi gas field

大牛地气田D 8-D 10井区上古生界为典型的多层系叠合致密砂岩气藏,以高密度分布水平井开发为主,投产后普遍存在高产稳产时间短、产量及油压递减快、资源采收率低等问题,需要从水平井单井治理和纵向转层两个方向进行稳产和提高气田采收率。通过井区340条井眼的随钻井斜、现场地层、岩性描述、X射线元素、气测及钻时等录井大数据建立地质模型,在地质模型约束下进行储层及含气层精细对比,并分别将导眼段、水平段录井地质特征与生产大数据对比,明确了水平井产能评价的关键参数,建立了水平井储量计算方法和相关参数核定标准,最后采用静态地质储量与动态可采储量对比分析剩余气分布,评价出静态地质储量高、动态可采储量低的可以治理水平井,并提交含气丰度高、可纵向转层的井段。

The upper Paleozoic in wellblock D 8-D 10 of Daniudi gas field is a typical multilayer superimposed tight sandstone gas reservoir,the development mode of high-density distributed horizontal wells is mainly adopted.After being put into operation,there are problems such as short time for high and stable production,rapid decline of production and oil pressure,low resource recovery ratio and so on.It is necessary to stabilize the production and improve the gas field recovery ratio from the two directions of single well regulation and longitudinal transfer layers of the horizontal wells.The geologic model was built through 340 mud logging big data about boreholes in the wellblock,including hole deviation while drilling,wellsite formation,lithology description,X-ray elements,gas logging,drilling time,etc.Under the constraints of geologic model,fine correlation between reservoir and gas-bearing bed was made,the mud logging geologic characteristics of pilot hole section and horizontal section were compared with the production big data,the key parameters of horizontal well productivity evaluation were clarified,and the calculation procedure of horizontal well reserves and the verification standard of relevant parameters were established.Finally,this paper analyzed the remaining gas distribution by the comparison of the static geologic reserves and dynamic recoverable reserves,evaluated the horizontal wells with high static geologic reserves and low dynamic recoverable reserves that can be regulated,and submitted the well sections with high gas abundance and longitudinal transfer layers.