Method for delineating geothermal anomalies by using daytime and nighttime thermal infrared remote sensing

Abstract

The invention provides a method for delineating geothermal anomalies by using daytime and nighttime thermal infrared remote sensing. The method includes the following steps that: Landsat 8 daytime data and ASTER nighttime data of the same day are acquired; the data are preprocessed; surface temperature inversion is performed, so that a daytime surface temperature grid map and a nighttime surface temperature grid map are obtained; corresponding grids are added, so that a thematic layer C can be obtained; a threshold t is calculated; in the thematic layer C, regions of which the temperature is lower than or equal to the threshold t are marked as temperature background regions, and regions of which the temperature is higher than the threshold t are marked as temperature anomaly regions; and urban regions and surface water body regions are removed from the temperature anomaly regions, so that a geothermal anomaly area thematic map D is obtained. According to the method of the invention, two kinds of thermal infrared remote sensing products with high spatial resolution are optimally selected so as to be used jointly, and therefore, it can be ensured that surface temperature products canhave high spatial resolution; daytime surface temperature and nighttime surface temperature are added, so that the relative cold and hot anomalies of natural objects at daytime and nighttime are eliminated, and surface high temperature anomalies under the influence of geothermy or human activities are highlighted; and the threshold is calculated according to bare soil and vegetations, so that surface temperature background values can be effectively suppressed, and surface temperature abnormal values are highlighted.

Description

technical field [0001] The invention belongs to the fields of thermal infrared remote sensing and remote sensing geology, and in particular relates to a method for delineating geothermal anomalies by utilizing day and night thermal infrared remote sensing. Background technique [0002] Thermal infrared remote sensing is very useful for detecting geothermal anomalies. However, due to the influence of specific heat capacity of different ground features, under the influence of solar radiation, the temperature rise and fall rates of different ground features are different, which leads to the relative hot and cold between different ground features. Anomalies interfere with the determination of geothermal anomalies. Eneva and Coolbaugh. (2009) pointed out that nighttime surface temperature inversion is of great significance when performing geothermal detection, but it is still difficult to eliminate the relative cold and heat anomalies caused by the difference in specific heat cap...

AI Technical Summary

Problems solved by technology

[0002] Thermal infrared remote sensing is very useful for detecting geothermal anomalies. However, due to the influence of specific heat capacity of different ground features, under the influence of solar radiation, the temperature rise and fall rates of different ground features are different, which leads to the relative hot and cold between different ground features. Anomalies, which interfere with the determination of geothermal anomalies

Eneva and Coolbaugh. (2009) pointed out that the inversion of surface temperature at night is of great significance when performing geothermal detection, but it is still difficult to eliminate the relative cold and hot anomalies caused by the difference in specific heat capacity of different ground objects

Therefore, geostationary observation satellites carrying thermal infrared imagers have become an ideal method for retrieving day and night surface temperature and detecting geothermal anomalies, but the spatial resolution of geostationary observation satellites carrying thermal infrared imagers is very small, such as the German Meteosat Second Generation satellite , the ground spatial resolution is only 3km

At the same time, Vaughan et al. (2012) pointed out that it is difficult to observe obvious ground temperature anomalies in Yellowstone Park with a spatial resolution of 1 km.

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