图像上凡大于0.2×0.2平方毫米的地质体,只要色调或色彩与背景地质体之间具有明显差别均可辨认。由于风化作用,地质体表面多被残积物、坡积物、土壤及植被所覆盖,因而在遥感图像上仅靠密度信息辨认各类地质体,是比较困难的。应主要根据图像上的结构信息分辨各类地质体。航天遥感图像目视解译的实践表明,4平方毫米(相当于地面4平方公里)以上 Any geological body larger than 0.2 × 0.2 mm2 in the image may be recognized as long as there is a clear difference between the hues or colors and the background geological body. Due to the weathering, the surface of the geological body is mostly covered by the residuals, slope sediments, soil and vegetation, so it is difficult to identify all kinds of geological bodies based on the density information only on the remote sensing images. Should be based on the structure of the image information to distinguish all types of geological body. Visual interpretation of aerospace remote sensing images shows that 4 mm2 (equivalent to 4 km above the ground)