Abstract:In order to restore the sedimentary environment and provenance of the Upper Wuerhe Formation in Well Block Jinlong-30 in Zhongguai Uplift, and study their effects for petroleum exploration. We tested and analyzed the major, trace elements and rare earth element of 13 sedimentary rock samples from the Upper Wuerhe Formation. The results disply that the abundance of oxides of major elements are close to PAAS and UCC, while the trace elements are both less than PAAS and UCC. The total ∑REE of the study area has a scope of content and characterized by glaring enrichment of light REE, and show slight negative anomalise of Eu. Before using these element datas, we cut down some effects from diagenesis and use several parameters for every problem to ensure the accuracy of the conclusions. Eigenvalue Sr/Cu and ∑LREE/∑HREE show that the paleoclimate of the upper Wuerhe Formation is warm and moist with abundant rainfall. Eigenvalue Mg/Ca and Sr/Ba show that the ancient aquatic environment is brackish water, as well as the redox-sensitive elements U and Th in the authigenic mineral show that the oxidizing condition of the ancient water. Under this circumstance, the upper Wuerhe Formation shows a Fining-upwards sequence, grain-size gets thinner from the old to new formations, and the ancient water gets more and more deep. Deposition environment changes from subaqueous distributary channel of fan delta-front to shallow lake. This produce many fine reservoir which benefit to become large oil and gas reservoir. Base on La/Th-Hf plot and characteristic of REE, it can be concluded that provenance of studied area mainly derived from felsic-predominant rocks and some basic rock. La/Sc-Ti/Zr plot and parameters of REE show that the structural setting of the studied area is land arc related to a continent, and the sediments are magmatic arc. The active tectonic movement of the continental island arc prompted the study area to form a “two convex and one concave” landform, which provided a space for sediments and was the basis for the formation of the fan delta sedimentary environment. The late volcanic activity was stopped by the Upper Urho Formation. The premise of the formation of clastic sediments.