摘要：Geochemical markers are the most important indicators of the sedimentary environment. The trace element characteristics in mudstone can reflect the medium environment well. Among the seawater and freshwater environment, the commonly used trace elements are: Sr, Ba, B, Ga, Rb and so on. In order to further demonstrate the sea-land transitional environment of the Late Paleozoic Ordos Basin, this study carried out mineralogical and geochemical analysis tests on mudstone samples in the drilling core and field sections of the eastern, southern and northwestern basins. The geochemical base profiles of the east-west and north-south directions in the basin were established respectively, and the test results of different horizons in different regions were compared and analyzed.
