Provenance Analysis Of Sandstones In The Upper Jurassic To Cretaceous Strata In The North Of Middle-up Yangzi Plate

The middle-up Yangzi Plate have experienced complex tectonic evolvement in Cenozoic. The configuration and formation of Huangling uplift, the relationship between the basin and the uplift, the tectonic transform in Cretaceous, and the evolvement of late-Jurassic to Cretaceous in the north of middle-up Yangzi plate are the problems that should be solved recently.The major target of provenance analysis is the paleo-geographic recovery and the basin analysis. There are multiple methods to analyze. This article uses detrital modes of sandstones to analyze the tectonic setting of Upper Jurassic to Cretaceous strata in the north of middle-up Yangzi plate combining with the characteristics of the sedimentary facies, sequence stratigraphy, paleocurrent and geochemistry. With the TriPlot software, we can use Dickinson triangle graphic to draw QtFl, QmFLt triangular diagram and QtFl, QmFLt, QpLvLs, QmPK assistant triangular diagram. Then we can make analysis and discussion, finally, deduce the tectonic setting of provenance.We analyzed 80 slices of sandstones from 5 sections in Zigui basin, Dangyang basin and Sichuan basin. The studies show that, from late Jurassic to Cretaceous, the samples from west partly lies in interior cratonic zone, partly lies in recycled orogenic zone. The samples from east almost all lies in recycled orogenic zone. Between early and late Cretaceous, the sedimentary facies, strata sequence, paleocurrent and geochemistry have changed obviously. So we can conclude that, from late Jurassic to Cretaceous, Qinling-Dabie orogenic belt and Huangling uplift were under the uplifting process, and supplied the sediments. The centre of the basin had moved from east to west. There is a tectonic transform between early and late Cretaceous.