The ecological environment problems are increasingly protruding in the Lower Cambrian black shale distribution area, wherein the radioactive pollution of the soil has aroused concern. It is now widely recognized that the distribution, mi-gration and environmental ecological toxicity of the radionuclide in soil environmental medium is not decided by their total content, but mainly by the chemical form in the medium. Through sequential chemical extraction technique and careful phase analysis of the extracted residue in each step along with micro area determination of uranium to study occurrence ...
