Characteristic in cretaceous and types of uranium mineralization in Ulancabu depression, Erlian basin, Inner Mongolia

A recent research about the tectonic types of Ulanchabu depression and deposition in Erlian Basin is dealed with, with the different genetic types of uranium mineralization, which was discovered in different layers by the previous study in the study area. It mainly wants to establish a close connection between the sedimentary characteristics of different tectonic evolution phase and uranium mineralization types. The study suggests that there are several layers that conducive to uranium mineralization and variety of uranium mineralization types in the area. Of these, alluvial plains or alluvial fans and lake deposition that formed in the upper Cretaceous Erlian formation, are advantageous to form sedimentary-diagenetic type uranium deposit; the river and marsh deposition that formed in lower Cretaceous Bayanhua Group Saihan Formation, are advantageous to form paleochannel type uranium deposit. Fan-delta, braided river delta and lake deposition that formed in lower Cretaceous Tenggeer Formation, are advantageous to form synsedimentary diving-interlayer oxidation type uranium deposit. (authors)