雄安新区高阳地热田蓟县系热储特征及资源量评估

Geothermal Reservoirs Characteristics and Resource Assessment of Jixian System in Gaoyang Geothermal Field,Xiongan New Area

雄安新区高阳低凸起区钻获华北盆地温度和产能最高的地热井,揭示雄安新区3000 m以深存在地热开发的第二空间——蓟县系碳酸盐岩热储。高阳低凸起区深部碳酸盐热储规模化开发在服务雄安新区生态文明建设和清洁供暖方面具有重要的意义。本文建立雄安新区范围高阳低凸起热储空间结构,初步查明了地热田雄安新区范围5000 m深度内的热储分布和性质。结果表明雄安新区高阳地热田深部主要为碳酸盐热储包括蓟县系雾迷山组、高于庄组。蓟县系雾迷山组顶界埋深3000~3500 m,厚度300~1000 m,热储温度100~120℃,出水量90~170 m^(3)/h,具有温度高、水量大、热储易于回灌的特点;高于庄组热储顶深3500~4200 m,一般厚度不低于800 m,热储温度一般在110~140℃,出水量50~100 m^(3)/h,可作为新区的后备资源。文章分析了深部碳酸盐热储空间结构,整个地热田分为三段,由西向东分别为西部凹陷区、中央隆起区、东部斜坡区。西部凹陷区西向东逐渐覆盖了寒武系、石炭二叠系;中央隆起区造上为雁翎潜山;东部斜坡区雾迷山组上部为古近系地层覆盖。本文通过热储法计算了雄安新区高阳地热田蓟县系热储年地热可采资源量折合标准煤86.72万t;数值法模拟了水位下降不低于150 m,开采井温度下降小于2℃条件下,蓟县系热储年地热可采资源量折合标准煤89.86万t热储法与数值法结果相近,评价结果可为高阳地热资源规划开发提供参考。

Geothermal wells with the highest temperature and productivity were drilled in Gaoyang low uplift region of Xiongan New Area in North China basin,revealing the existence of the second space for geothermal exploitation in the deep part of Xiongan New Area,the Jixian carbonate rock geothermal reservoir.The large-scale developent of deep carbonate geothermal reservoir in Gaoyang Low uplift is of great significance in serving the construction of ecological civilization and clean heating in Xiongan New Area.In this paper,the geothermal reservoir space structure of Gaoyang low uplift in Xiongan New Area is established,and the geothermal reservoir distribution and properties within 5000 m depth of the geothermal field in Xiongan New Area are preliminatively identified.The results show that the deep carbonate reservoirs in Gaoyang geothermal field are mainly composed of Wumishan Formation and Gaoyuzhuang Formation of Jixian System.The top boundary of Wumishan Formation in Jixian system has a burial depth of 3000~3500 m,a thickness of 300~1000 m,a geothermal reservoir temperature of 100~120℃,and a water yield of 90~170 m^(3)/h.It exhibits characteristics including high temperature,large water volume and easy reservoir recharge.The top boundary of Gaoyuzhuang Formation has a burial depth of 1425~4200 m,and the thickness is generally not less than 800 m.The formation temperature is generally 110~140℃,and the water volume is about 50~100 m^(3)/h,which can be used as the reserve resources of the new area.The spatial structure of deep carbonate geothermal reservoir was analyzed.The whole geothermal field is divided into three sections,which are west depression area,central uplift area and east slope area respectively from west to east.The western depression area gradually covers the Cambrian and Carboniferous Permian from west to east.The central uplift area is Yanling buried hill;The upper part of Wumishan Formation in the eastern slope area is covered by Paleogene strata.In this paper,the recoverable geothermal resources of Jixian Systerm in Gaoyang geothermal field are calculated as 867200 tons of standard coal respectively by geothermal reservoir method.Numerical simulation results show that the annual recoverable geothermal resources of Jixian Systerm are equivalent to 89.86×104 t of standard coal under the condition that the water level drop is no less than 150 m and the temperature drop of mining well is less than 2℃.The results of the geothermal reservoir method and the numerical method are similar,and the evaluation results can provide reference for the planning and development of geothermal resources in Gaoyang.