Abstract:

The authors analyzed the 1∶50,000 stream sediments data in the Chabaqi area of Inner Mongolia with the Rmode factor analysis method, and eight representative factors were extracted from the data. The geochemical divisions have a close relationship with the geological bodies by making a study of the factor score map, the geochemical division map and the geologic map. The element combination of arsenic, stibium, copper and zinc is mainly related to the Linxi Formation，and the distributions of division are in accordance with those of the Linxi Formation. The lead and zinc divisions are mainly distributed in the andesite and dacite of the Guanghua Formation,metamorphic rocks of the Laolongtou Formation, and tonalite of Early Jurassic，they are mainly distributed in the NE direction. Besides smaller divisions are distributed in the north of the study area, divisions of silver and tungsten are mainly distributed in the Late Jurassic adamellite of the south study area, and the distributions show that elements of silver and tungsten have closed relation to the granite body. A gold ore occurrence was found in the arsenic, stibium, copper and zinc divisions, and a leadzinc ore occurrence is located in the lead and zinc divisions during field practical investigation. By the study of geochemical division, we have known the geologicalgeochemical implications and their reciprocal relationships. The research method can provide some significant information for the geological survey.

Key words: factor analysis, stream sediment, geochemical division, Chabaqi area of Inner Mongolia