REE of samples collected from shale of Upper Cambrian Niutitang Formation at the northern margin of the Upper Yangtze platform along the field outcrop section are analyzed to discuss its material source and sedimentary environment.The total amount of rare earths of the sample is relatively high,and differentiation degree of LREE and HREE relatively high.LREE are enriched and HREE depleted.The REE pattern shows that LREE curves lean to right and those of HREE flat with slight negative δEu a-nomaly and slight positive δCe anomaly.The Ceanom value generally reflects main anaerobic reducing envi-ronment of the seawater during deposition which is conducive to the preservation and enrichment of organ-ic matter and favorable for formation of high-quality hydrocarbon source rocks.From east and west to central part of the study area deposition rate increases indicating that the central part is supplied with a-bundant material from Hannan paleo-uplift.The structure background of material source is a magma arc cut by continental island arc.Material source of the east and west parts may multiple.Sedimentary rocks and continental tholeiite are the main source of the central part.
Rare earth elementsNiutitang FormationShaleSediment sourceThe Upper-Yangtze Region
万方数据
维普
