Using the Mono-Window Algorithm of ETM+6 Date to Interpret Geothermal Anomaly in Fuzhou Basin, China

Fuzhou Basin is abundant in geothermal resource, which has a broad developing prospect as a new type of clean energy source without secondary pollution. In this paper, we interpreted the land surface temperature of Fuzhou Basin area by mono-window algorithm (Qin Zhihao, 2001) of ETM+6 thermal infrared band. Atmospheric transmittance, atmospheric average temperature and surface emissivity are the crucial parameters of mono-window algorithm. Atmospheric transmittance and atmospheric average temperature can be obtained on the basis of local meteorological data with the empirical formula; How to estimate surface emissivity is a key and difficult step in mono-window algorithm. First, this paper applied the atmospheric correction procedure to the RS raw data, and a supervised classification analysis was used to get the land use/land cover (LULC) information. Subsequently the surface emissivity of different types of LULC was estimated using a foregone formula. According to surface temperature inversion results binding the existing geothermal anomaly loci, we can preliminarily analyze the relationship between geothermal anomaly loci and surface temperature. Finally, possible geothermal anomaly area in Fuzhou Basin was identified with ArcGIS software. The result shows that the area where surface temperature ranges from 28°C to 36°C can be considered as potential geothermal anomaly spots. The interpreted geothermal loci are consistent with the actual situations of developing geothermal wells. It is thus clear that the mono-window algorithm suitable for the interpretation of geothermal anomaly area under a heavy land cover.