Identification of lithology-structures and quartz veins in the Heijinshan area of Dunhuang City, Gansu Province based on GF-2 satellite image

Domestic GF-2 sub-meter level satellite images have revealed a great application potential in geological exploration. However, the satellite images have been little documented in lithology and structure identification. Taking the Heijinshan area of Dunhuang City in Gansu Province as an example, this work established the technical flowchart of the GF-2 data, preprocessed the GF-2 four-band fused reflectance data by radiometric calibration and atmospheric correction, and conducted geological interpretation using visual interpretation methods. Quartz veins in the Heijinshan area were also extracted based on the decision tree algorithm. This study revised previous geological mapping, delineated precise geological and lithological boundaries, and newly identified the distribution of two basalt sections within the lower member of the Lower Carboniferous Hongliuyuan Formation. A five-layer decision tree was constructed to eliminate interfering features layer by layer, and more than ten large-scale quartz veins were well identified. These quartz veins were mainly distributed in the metamorphic clastic rocks of the lower Hongliuyuan Formation of the Lower Carboniferous, and were also developed in the Late Permian diorite granite. This study indicates that GF-2 remote sensing data can play a dominant role in the interpretation of lithology-structure and quartz veins.