遥感影像地表温度反演与地热资源预测——以石家庄地区为例

热红外遥感技术可以反演地表温度信息,可在地热资源预测方面发挥重要作用。研究基于京津冀地区地热成藏模式,利用单窗算法反演出石家庄地区2015年3月6日地表温度,结合夜间热红外影像、遥感构造解译结果和剩余重力异常数据,综合分析,相互论证,圈定1处山地对流型地热远景区和2处沉积盆地型地热远景区。其中,平山县寺沟村昼夜地温值均高于周边地物,且剩余重力异常数据印证该区存在北东向断裂,进而预测该区是断裂作为导水导热通道连接地表与地壳深部热源所形成的地热田;藁城—无极一带和马于—换马店一带剩余重力异常解译为深部隆起构造,且有隐伏断裂穿过,预测该区是由隐伏断裂将热量传递、汇集至隆起构造位置所形成的地热田。以地热成藏理论为依据,利用遥感技术和地质、地球物理资料综合分析进行地热资源预测,所圈定的地热预测靶区更具备地质可解释性。

Land surface temperature retrieval and geothermal resources prediction by remote sensing image: A case study in the Shijiazhuang area, Hebei province

Thermal infrared remote sensing technology can retrieve land surface temperature information, which has played an important role in the prediction of geothermal resources. Based on the geothermal accumulation theory of the North China Plain, the mono-window algorithm was used to retrieve the land surface temperature of the Shijiazhuang area on March 6, 2015. Combined with the night thermal infrared images, remote sensing structure interpretation results and residual gravity anomaly data, through the comprehensive analysis and mutual demonstration, one upland convection-type and two sedimentary basin-type prospective areas were delineated, whose formation modes were convection and conduction respectively. In Sigou Village of Pingshan County, the land surface temperature is higher than that of the surrounding land features day and night, and the residual gravity anomaly data confirm the presence of NE faults in this area. Therefore, it is inferred that this area is a geothermal field formed by faults as water and heat conduction channels connecting the surface and the deep crustal heat source. The Gaocheng-Wuji area and Mayu-Huanmadian area are interpreted as deep uplift structures base on the residual gravity anomaly data, and there are hidden faults passing through, suggesting that this area is a geothermal field formed by the heat transfer and collection from the hidden faults to the uplift. This study is a geothermal resource prediction that based on the geothermal accumulation theory and the comprehensive analysis of remote sensing technology and geological and geophysical data. The prediction of target area is geologically interpretable and more in line with the understanding of geothermal accumulation.