关键词: 
remote sensing /
Nenjiang River /
placer gold deposit /
image processing /
interpretative signs /
perspective effect

摘要: The practice has proved that it is an economic and effective method to investigate placer gold deposit by using multi-level information sources of remote sensing and multi-variate analysis methods, especially for the area with a sparse population and difficult condition like the Da Hinggan Mountains, China.The information sources used in our work includes Landsat TM, aerial infrared photography and their mosaic image maps and enlarged photos with different scales. According to statistic data, in the study area the gold-bearing rocks are mainly granite, alaskite, granodiorite and some old metamorphic rocks. On gold-bearing geological structures, the fault zones in the four directions (NE, NNE, NW and EW) are obvious, in which NNE and EW are the most key fault zones. On fluvial geomorphology the flow courses stored placer are in the tributaries of the 4th and 5th levels, especially in straight or slight curve reaches. On the basis of analysis the interpretative signs were set up, and the interpretative work began on a sheet of picture with a single band at first, furtherly, the integral interpretation on color enlargement pictures the extraction and composition work was carried out by means of multicolor digital analyzer, and computer image processing equipment with the VAX 11/ 750 as a host computer so as to draw up the relatively specialized maps of placer deposit and delimit the locations of ore body on the pictures or on the screen. Finally, the satisfatory effect was achieved through a series of comprehensive analyses.