Sedimentary physicochemical indicators and typical landscape, landform and sedimentary photos of the Yarlung Zangbo River Basin (July 2019-august 2019)

The data are the typical landscape, geomorphology and sedimentary strata photos obtained by the thematic group in the lower reaches of Yajiang River and Niyang River Basin from July to August 2019, as well as the physical and chemical indexes of loess and river sediments, mainly including: (1) 14C sample sampling and age in the lower reaches of Niyang River; (2) Chronological results of OSL in the lower reaches of Niyang River; (3) XRF of lacustrine sediments and Langou loess in the lower reaches of Niyang River; (4) Magnetic susceptibility of Lamawan lacustrine sediments and Langou loess in the lower reaches of Niyang River; (5) Grain size of Langou loess in the lower reaches of Niyang River; (6) Elements in the lower reaches of Yarlung Zangbo River and Niyang River Basin. The photos mainly show glaciers, rivers, lakes and other landscapes, as well as landslide surface, glacier shear surface and sedimentation.

0 2021-09-09

Liguo intrusive database of the Liguo Fe Cu Au deposit in the southern margin of the North China Craton (2018-2019)

The data set includes major and trace elements, Sr Nd isotopic compositions of the whole rock, major and trace elements of apatite and sr-o isotopic compositions of apatite in the Liguo iron copper gold deposit. The main and trace elements of the whole rock were analyzed in Aoshi analysis and detection (Guangzhou) Co., Ltd. after lithium metaborate melting, the main and trace elements were analyzed by X-ray fluorescence (XRF) spectrometer, and the accuracy and accuracy were within 1%. The trace elements were analyzed by ICP-MS, and the accuracy and accuracy were within 5%. The SR Nd isotopic compositions were analyzed by MC-ICP-MS in Guangzhou Institute of geochemistry, Chinese Academy of Sciences. The normalized values of 143Nd / 144Nd and 87Sr / 86Sr ratios are in good agreement with those of the reference samples. Apatite was collected from whole rock samples using standard crushing, sieving, heavy liquid separation and magnetic separation techniques, then mounted in an epoxy resin tray and polished to nearly half of the section to expose the internal structure. The major elements of apatite were analyzed by EPMA in the second Institute of Oceanography, State Oceanic Administration. Trace elements were analyzed by in situ La ICP-MS in the Key Laboratory of Mineralogy and metallogeny, Guangzhou Institute of geochemistry, Chinese Academy of Sciences. The ablation time was 40 s and the diameter of laser spot was 43 μ m. The repetition rate is 6Hz. Nist610 was used as the main external calibration standard, and 43Ca (determined by quantitative electron microprobe method) was used as the internal standard. Drift correction, off-line selection, integrated background and analytical signals, and quantitative calibration of trace elements are all calibrated by ICP-MS datacal software. Apatite in-situ Sr isotope analysis was performed at the State Key Laboratory of continental dynamics, Department of geology, Northwestern University. The ablation time was 50s and the laser spot diameter was 60 μ m. The repetition rate is 6Hz. The isotopic composition of apatite was calibrated according to sr987 and Alfa SR standards. The 87Sr / 86Sr ratio of apatite standard sr987 and alfasr are 0.71025 and 0.71025, respectively ± 21(n=29,2 σ) 70727 ± 32(n=30,2 σ)。 In Beijing shrimp In situ oxygen isotope analysis of apatite was measured in the center. Shrimp IIE / MC is equipped with a detachable CS main ion source, an electron gun, multiple collectors and Helmholtz coils for high-precision O isotope measurement. Every 18O / 16O analysis takes about 7 minutes, the spot diameter is 23 μ m。 The calibration was performed with the isotopic composition of Durango apatite. Field measurement of Durango Phosphorite δ The average value of 18O was 9.81 ± 0.66‰(2 σ), It is similar to the results of previous studies within the error range. Therefore, the above data are reliable. The data set includes geochemical and isotopic characteristics of the ore bearing rocks and their phosphorites, which can help us understand the petrogenesis and the controlling factors of mineralization. The phosphorites from group I and group II are magmatic fluorine-bearing phosphorites, characterized by negative Eu anomaly, LREE enrichment and hree depletion. At the same time, both groups had higher Sr / Y and Sr / y ratios δ EU indicates the porphyry adakite characteristics of the source rocks. Compared with the isotopic compositions of the whole rock, the values of 87Sr / 86Sr (0.70250-0.71262) and δ 18O (6.22-9.00) values indicate the contribution of mantle, crust and / or sediment derivatives. Although group I apatite and group II phospholimestone have similar geochemical characteristics, group I apatite crystallizes prior to plagioclase, without SR - (LA / Yb) n / (LA / SM) n / (SM / Yb) n correlation, while group II apatite crystallizes in accordance with plagioclase, with positive correlation. These elements are sensitive to redox environment( δ Eu、 δ The geochemistry of CE, MnO and V shows high oxygen fugacity (between HM and NNO). The oxygen fugacity of group I apatite system is higher than that of group II apatite system. More importantly, the different characteristics of trace elements and oxygen fugacity between the first group of apatite and the second group of apatite can be used as mineralization indicators to map the range of iron copper gold mineralization for the first time. In addition, the estimated contents of F and Cl in the parent magma (F = 1300-2446ppm, CL = 140-4780ppm) are higher than those in the original mantle and the average continental crust, indicating the enrichment process of F and CL. Based on the characteristics of adakites, high oxygen fugacity and high fluorine and chlorine content, it is speculated that subduction of the Pacific plate may be the main dynamic mechanism of diagenesis and mineralization of Liguo.

0 2021-05-17