Abstract:

Qiangtang basin is located in the middle of QinghaiTibet Plateau, where the weather is atrocious and the uranium geologic research was little. This paper primarily presented the radioactive characteristics about the strata in Qiangtang basin and the granite in southeast outside of basin based on the following data,radioactivity gamma.ray spectrum survey in field, some chemical analysis data of granite, car.borne gamma.ray spectrometry made by other geological department, and a few regional investigation material so on. Studies show that the Middle and Upper Jurassic Xueshan Formation, Quemocuo Formation and Xiali Formation have fairly high uranium content,their average uranium content in the northeast slope zone are 4.12×10^-6,4.06×10^-6 and 3.68×10^-6,respectively. In the northern Qiangtang depression, the average uranium content for Xiali Formation is 7.75×10^-6, and 5.93×10^-6 for Suowa.Xueshan Formation. From the viewpoint of spatial variation, the average uranium content of strata in the south of northern Qiangtang depression is higher than that in the north. While in northeast slope zone, the average uranium content is characterized by high in the middle and the north, and low in the south. These data and analysis results in this paper can be served as the significant radioactive basis for analyzing the geological condition of uranium ore.formation in Qiangtang basin.

Key words: uranium metallogenetic condition, car-borne gamma spectrometry, Qiangtang basin