雄安新区地温场特征及其控制因素

Geothermal Field Features and Their Control Factors in Xiongan New Area

雄安新区地热资源丰富,本文通过对地热井资料的收集分析,并对单井地温梯度值进行计算,结合区域资料,编制本区盖层地温梯度等值线图,并分析了地温梯度值纵横向变化规律及影响因素。本区地温梯度值基本上都在3.0℃/100m以上,局部达到6.0℃/100m;平面上,地温梯度值总体特征是北高南低、中间高两侧低的特点;纵向上,盖层地温梯度值高,热储层内部地温梯度值低;其地温场的变化主要受地质构造、地层岩性、盖层、水文地质条件等因素控制,其中由于地质构造的影响,加上岩石热导率之间的差异,造成来自地幔的热量向上传递过程中重新分配,向背斜核部集中,导致盖层局部地温梯度值高。

Geothermal resources in the Xiongan new area are abundant.Through data acquisition and analysis from available geothermal wells,the paper has carried out single well geothermal gradient computation.Combined with regional data have compiled overburden geothermal gradients isogram in the area,analyzed geothermal gradient horizontal variation pattern and impact factors.Geothermal gradients in the area are basically above 3.0℃/100m,locally can be 6.0℃/100m as high.On plane,as a whole geothermal gradients present features of high in the north,low in the south;high in the kernel,low in the flanks.Vertically,geothermal gradients present features of high in the overburden,low in the geothermal reservoir interior.The variation of geothermal field is mainly controlled by factors of geological structure,strata lithology,overburden,hydrogeological condition etc.In which,owing to impact from geological structures,add in with different rock thermal conductivities bring about mantle heat quantity redistribution during upward transfer process,concentrating on the core of anticline have caused high local overburden geothermal gradients.