Provenance analysis serves to reconstruct the predepositional history of a sediment/sedimentary rock. This paper focuses on the reconstruction of the provenance and tectonic settings of the Niger delta clastic facies using geochemical approach. The main types of geochemical tests include major, trace, and rare earth element (REE) tests. Twenty-one samples of shales and sandstones units were purposely collected from a depth between 1160 and 11,480？m, grinded, pulverized, and sieved with a <75？μm. About 5？g was packed and sent to Acme analytical Laboratory Ltd., Vancouver, Canada. The analyses were carried out by both induced coupled plasma-mass spectrometry (ICP-MS) and induced coupled plasma-emission spectrometry (ICP-ES). Bulk-rock geochemistry of major oxides, trace elements, and rare earth elements was utilized for the provenance and tectonic setting determination. Based on the discrimination diagram for major oxides, the probable provenance of the south eastern Delta clastic sediments was mainly of the active continental margins. The bivariate plots of La versus Th, La/Y versus Sc/Cr, and Ti/Zr versus La/Sc and the trivariate plots of La-Th-Sc, Th-Sc-Zr/10, and Th-Co-Zr/10 are all plotted on the fields of active continental margin sediments which is consistent with the known actively opening of a failed arm of triple junction. The trace elements and REE analysis indicates that they are virtually Fe-rich, lithic/quartz arkosic sandstones. The normalizing factors used for the REE are Wakita chondrite. Their rare earth elements (REE) pattern displays high light REE/heavy REE (LREE/HREE) ratio, flat HREE, and a significant negative Eu anomaly which correlate well with the UCC and PAAS average composition. The source area may have contained felsic igneous rocks. 1. Introduction The samples were taken from Y-field in Niger delta. The coordinates of the study area were not given because of the proprietary nature of the data but the estimated location is shown in Figure 1. The Niger delta extends from about longitudes 3° E and 9° E and latitudes 4°30′ N to 5°21′ N. The Niger delta is located in the southern part of Nigeria. The Niger delta is situated in the Gulf of Guinea, which northwards merges with the structural basin in the Benue and middle Niger terrain holding thick marine paralic and continental sequence. The onshore portion of the Niger delta province is delineated by the geology of southern Nigeria and southwestern Cameroon. The Niger delta was formed as a result of basement tectonics related to the crustal divergence during the late Jurassic to
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