Abstract
Study on surface geothermal heat-flow for future quantitative geothermal heat-flow survey by thermal infrared remote sensing was done. Nighttime heat budget equation at a geothermal surface is given, and geothermal heat-flow intensity is categorized into three grades based upon the intensity of solar energy and geothermal heat energy. Diurnal temperature measurements across the earth-air interface were done at geothermal surfaces, and one experimental example of limitation of detectable heat-flow intensity was obtained.
