东胜煤田地质封存三维深地建模

Three-dimensional deep modeling of geological storage for Dongsheng coalfield in northeastern Ordos basin

深部地质封存是目前最具前景的高盐水及二氧化碳地质封存方式。以钻孔数据库为基础,结合地形及地质数据资料,利用Surpac软件构建了鄂尔多斯盆地东北部东胜煤田地质封存潜力区的三维地质模型,模型共收集了研究区内8口深度超过2000 m的深井资料,构建了覆盖鄂尔多斯盆地东北部深地封存潜力区的三维地质模型,通过分析模型中地层展布几何学特征,结合示范工程岩心测试分析结果,总结研究区内深部地质封存潜在储层刘家沟组的赋存形式、封存有利特点及变化特征。研究结果表明:研究区范围内潜在封存储层刘家沟组整体地层厚度变化不大,但总体而言区域西南部刘家沟组比东北部深度更深、地层厚度更大,具有更大的潜在封存空间,可积极开展深部地质封存科学实践;刘家沟组长石砂岩为封存提供了微裂隙空间,是使该地层成为封存有利层位的重要特征,根据三维地质建模结果显示,研究区内刘家沟组总体厚度处于277~460 m之间,潜在封存空间可达2790000 km3;由于当前已有地质封存示范工程数量较少,因此该模型可为少量钻孔数据背景下的区内其他缺少钻孔数据的封存层位深度及厚度变化判断提供参考。

Deep geological storage is the most promising way of high brine and carbon dioxide geological storage.Based on the borehole database,combining with the terrain and geological data,the 3D geological modeling software Surpac was used to construct the 3D geological model for Dongsheng coalfield in northeastern Ordos basin.The data of 8 deep wells with a depth greater than 2000 m in the study area were collected in the model.A deep ground model covering the area of deep geological storage in northeastern Ordos basin was constructed.By analyzing the geometric characteristics of the strata distribution in the model,and combining with the core test analysis results of the demonstration project,the occurrence forms,favorable characteristics and changing characteristics of the deep geological storage potential reservoir Liujiagou formation in the study area were summarized.The main conclusions are as follows:In the study area,thickness of the Liujiagou formation changes little,but in general,the southwest side of the formation is deeper and thicker than that of the northeast side,and the potential sealing space is larger,the scientific practice of deep geological sequestration can be actively carried out in this region.The existence of arkose in Liujiagou formation provides micro-fracture space for storage,which is an important feature of the target layer for storage;according to the results of three-dimensional geological modeling,the overall thickness of Liujiagou formation in the study area is between 277~460 m,and the potential storage space can reach 2.79 million km3.Due to the few number of demonstration projects,the model can provide a reference of the depth and thickness changes of Liujiagou formation in the region that lack drilling data under the background of a small amount of drilling data.