The data set is the original repeated GPS observation data along Paizhen - Motuo active deformation Himalayan orogenic belt in Southeast Tibetan Plateau. The data are measured in 2021, including the data of 18 stations, and the data quality is good. Through the observation data of these observation points, we can reveal the horizontal and vertical distribution characteristics of the northward converging strain of the Indian continent in the key parts of the Himalayan orogenic belt. And we can understand the current uplift state of the Himalayan orogenic belt and its correlation with horizontal movement, and combine with the active faults. Based on the theory of motion dislocation, the quantitative distribution of strain between earthquakes could be studied, as well as the strain accumulation characteristics, fault locking range and fault locking level between earthquakes, which provide important constraints for evaluating the seismic risk of active faults in the study area.
HE Jiankun
The data of Cenozoic plant macrofossils on the Qinghai Tibet Plateau includes leaves, seeds and fruits. It includes Latin and Chinese names of families, genera and species, times, places of origin, morphological descriptions, discussions, specimens and references. The species names are assigned according to the original literature. For fossil records revised by later research, the revised records were chosen; The age of the origin (fossil site) is assigned according to the latest literature. The terms and description paradigm of leaf shape description are referred to the book "Leaf Structure Manual"; The length, angle, and other measurement data in the description are derived from the original literature. The fossil records of the document are sorted alphabetically by Latin initials of families and genera. The data can provide important clues for studying the coupling relationship between the environmental climate changed and the evolution of vegetation and plant diversity in the Cenozoic Qinghai Tibetan Plateau.
ZHOU Zhekun , LIU Jia , CHEN Linlin , ROBERT Spicer , LI Shufeng , HUANG Jian , ZHANG Shitao , HUANG Yongjiang , JIA Linbo , HU Jinjin , SU Tao
Through the joint inversion of seismic waveforms and InSAR coseismic displacement data, our study revealed the spatiotemporal and spatial source rupture processprocesses of the two strong earthquakes that occurred in struck the eastern Tibetan Plateau atin May 2021. The results show that the Yangbi earthquake, which occurred in along the southeastern margin of the TibetTibetan Plateau, was a Mw6.1 event with characterized by unilateral right-dextral strike-slip rupture and 8s an 8 s duration. The In addition, the Maduo earthquake, which occurred in the interior of the Tibetan Plateau, was a Mw7.5 event with characterized by left-sinistral lateral-strike- slip extendedextending along both sides of the earthquake seismogenic fault and 36sa 36 s duration. The rupture properties of these two strong earthquakes reflect the deformation characteristics of different parts of the eastern Tibetan Plateau,. and also These events also caused the increase of the Coulomb stress of the surrounding active faults to increase, so we should pay attention to the risk potential of future earthquakes should be evaluated.
WANG Weimin
The Cenozoic strata developed within and around the Tibetan Plateau, contain fruitful information on the tectonic evolution, paleoenvironment and paleoclimate changes. It's very significant on revealing the history of the uplift and deformation of the Tibetan Plateau and its relevant effects on the regional and even global environment and climate. This data set contains several well developed sections, which have been identified by the systematic geological survey. Depending on the tools (e.g. GPS, geological compass) in the fieldwork, we have finished the geological measurements and descriptions of these sections as well as the relevant geological maps. It includes a 90-m loess deposit of the Duikang section in the Linxia basin, several fluvial and lacustrine deposits (such as the 1890-m Dayu section in the Lunpola basin, the 300-m Shuanghe section in the Jianchuan basin, the 252-m Caijiachong section in the Qujing basin) and a 932-m saline lacustrine deposit with gypsolyte of the Jiangcheng section in the Simao basin. This data set provides a solid geological foundation for the following researches on stratigraphic chronology, tectonic evolution, paleoenvironment and paleoclimate, and so forth.
FANG Xiaomin , FANG Xiaomin, YAN Maodu, ZHANG Weilin, ZHANG Dawen
The Wuyu Basin is bounded by the Gangdese Mountains to the north and the Yarlung Tsangpo River to the south, and is a representative basin to study the Cenozoic tectonism of the southern Tibet. The sedimentary strata in the Wuyu Basin include the Paleocene-Eocene Linzizong Group volcanics and the Oligocene Rigongla Formation (Fm.) volcanics, the Miocene lacustrine sediments of the Mangxiang Fm. and Laiqing Fm. volcanics, the late Miocene-Pliocene Wuyu Fm., and the Pleistocene Dazi Fm. Five sandstone samples from the Mangxiang Fm., Wuyu Fm. and Dazi Fm. and one modern Wuyu reiver sand sample were collected for detrital zircon U-Pb dating using the LA-ICP-MS method. Detrital zircon U-Pb ages in the Mangxiang Fm. show a large cluster at 45-80 Ma; those in the Wuyu Fm. show a large cluster at 8-15 Ma and a subsidiary cluster at 45-70 Ma; those in the Dazi Fm. show three large clusters at 45-65 Ma, 105-150 Ma and 167-238 Ma; and those in modern Wuyu river show a large cluster at 8-15 Ma and a subsidiary cluster at 45-65 Ma (Figure 1). Late Cretaceous-early Eocene zircons in all samples are consistent with the most prominent stage of magmatism of the Gangdese Mountains; the 8-15 Ma zircons in the Wuyu Fm. and modern Wuyu river are consistent with the magmatism of the Laiqing Fm.; and the Triassic-Jurassic zircons in the Dazi Fm. are consistent with the magmatism of the central Lhasa terrane. The results of detrital zircon U-Pb ages and sedimentary facies analyses in the Wuyu Basin indicate that the southern Tibetan Plateau suffered multi-stage tectonism-magmatism since the India-Asia collision: (1) Paleogene Linzizong Group-Rigongla Fm. volcanics; (2) tectonism-magmatism at ~15 Ma ended the lacustrine sediments of the Mangxiang Fm. and resulted in volcanism of the Laiqing Fm.; (3) tectonism at ~8 Ma resulted in the volcanic rocks of the Laiqing Fm. becoming one of the main provenances for the overlying Wuyu Fm.; (4) the Wuyu Basin formed braided river and received sediments from the central Lhasa terrane to its north at ~2.5 Ma. The geomorphic pattern of the southern Tibet has gradually formed since the Quaternary.
MENG Qingquan MENG Qingquan
(1) The data content is the stress monitoring data of the high slope of zhala hydropower station, including the stress data of the automatic monitoring of the high slope of zhala hydropower station, which has certain guiding significance for the stability of the slope of zhala hydropower station and can provide data support for disaster prevention and reduction of zhala hydropower station; (2) The data comes from the automatic transmission of automatic monitoring equipment, and is automatically interpreted and processed by the software of monitoring and early warning platform to finally generate the data in Excel; (3) The data transmission is stable and the quality is high, which can provide a basis for the slope stability of zhala hydropower station; (4) The data can reflect the stress variation of the high slope of zhala hydropower station, and has a wide application prospect.
XU Kunzhen
(1) The data content is the deep displacement monitoring data of the high slope of zhala hydropower station, including the deep displacement data of the automatic monitoring of the high slope of zhala hydropower station, which has certain guiding significance for the stability of the slope of zhala hydropower station and can provide data support for disaster prevention and reduction of zhala hydropower station; (2) The data comes from the automatic transmission of automatic monitoring equipment, and is automatically interpreted and processed by the software of monitoring and early warning platform to finally generate the data in Excel; (3) The data transmission is stable and the quality is high, which can provide a basis for the slope stability of zhala hydropower station; (4) The data can reflect the deep displacement change of the high slope of zhala hydropower station, and has a wide application prospect.
XU Kunzhen
(1) Data content: This data set is based on the Xiaguiwa landslide in the Sanjiang basin of the Qinghai-Tibet Plateau, reconstructing the bedding slope of the Xiaguiwa landslide; the bedding slope of the Xiaguiwa landslide is used as a reference for shaking table model tests, which is used to design the shaking table model test model and sensor layout diagram for the bedding rock slope, with a weak rock layer in the model slope, and the sensors deployed are acceleration sensors and velocity sensors, and the measured (2) Data source and processing method: The data set is drawn by Guo Mingzhu of Beijing University of Technology using CAD software. (3) The data provide reference for the subsequent shaking table model test implementation.
GUO Mingzhu
(1) Data content: This data set is based on the Xuelongnang landslide in the Sanjiang basin of the Qinghai-Tibet Plateau, and reconstructs the counter-bedding slope before the slide; the counter-bedding slope before the slide is used as a reference for the shaking table model test, which is used to design the shaking table model test model and the sensor layout diagram for the counter-bedding rock slope, and a special joint is set in the model slope, and the deployed sensors are the acceleration sensors and the velocity sensors. (2) Data source and processing method: The data set is drawn by Guo Mingzhu of Beijing University of Technology using CAD software. (3) The data provide reference for the subsequent shaking table model test implementation.
GUO Mingzhu
The Paleogene marine strata in southern Tibet are well developed and rich in foraminifera and other marine fossils. Based on the study of macroforaminifera taxonomy and Stratigraphy in the West Tethys domain (mainly the Mediterranean region), western scholars established the Paleocene Eocene macroforaminifera biostratigraphy in 1998. Compared with Tibet in the East Tethys domain, the development of macroforaminifera in the Paleocene in the Mediterranean region is relatively poor. Therefore, the accuracy of biostratigraphy based on sittis foraminifera is low. In this study, detailed profile survey and high-density sample collection of lower Paleogene carbonate sedimentary strata in guru area, southern Tibet are carried out to supplement and improve the biostratigraphy of macroforaminifera in southern Tibet on the basis of macroforaminiferal taxonomy research; Based on biostratigraphy and carbon isotope stratigraphy, a high-resolution chronostratigraphic framework is established. A total of 7 profiles were measured in this study, and the profiles are located between 89 ° 11 ′ ~ 89 ° 13 ′ E and 28 ° 3 ′ ~ 28 ° 7 ′ n; The elevation range is 4643 ~ 5380 M. Based on the observation of rock slices in the laboratory, the age of the measured strata is preliminarily judged. P2 section is a limestone sequence overlying the late Cretaceous strata, representing the earliest Paleocene sedimentation in the study area; P1 section is a set of very thick limestone deposits of lower Paleocene; Section E2 is the top of Paleocene, close to the Paleocene / Eocene boundary; The ages of sections E1, E3, E3s and E4 are roughly early Eocene; The grayish green marl and red shale at the top of section E4 represent the latest marine strata in the study area. We plan to conduct detailed taxonomic and stratigraphic studies on foraminifera in these sections to establish high-resolution large foraminifera biostratigraphy; At the same time, we also need to analyze the changes in composition and abundance of macroforaminifera, and further explore the evolution process of macroforaminifera in early Paleogene. For the sandstone strata in the section, we need to conduct detrital zircon U-Pb isotope analysis, the obtained age and biostratigraphic data confirm each other, and further explore the paleogeographic evolution process under the influence of India Eurasia collision.
ZHANG Qinghai
On the basis of field scientific research, this parameter set integrates the parameters of debris flow disaster chain and landslide disaster chain observed along important roads in Himalayan and Hengduan Mountains. The regional scope covers Nyingchi, Shannan, Bomi, Basu, Shigatse, Ali and other regions of the Tibet Autonomous Region, as well as the East Asia rift valley of the China India channel. The source and mode of data production are processed according to the original data obtained from field scientific investigation. This parameter set is mainly based on the field investigation to determine the location and type of disaster and disaster chain, the damage of major highway projects and other information, and then sorted into tables and shp files. It is hoped that this data can provide help for disaster prevention and reduction of road projects in the Qinghai Tibet Plateau.
DENG Hongyan
On the basis of satellite image recognition, this data set catalogues and photographs the debris flow disaster chain and landslide disaster chain observed in the Himalayas and its surrounding areas; And fill in the data form, scientific examination log file and distribution map. Discipline scope of this data set: information and system science related engineering and technology - > systematic application of information technology - > geographic information system. This data mainly determines the location and type of disaster and disaster chain through field investigation, and then arranges it into tables and generates original data such as vector data and scientific research logs. The field scientific research areas include Nyingchi, Shannan, Bomi, Basu, Shigatse, Ali and other areas of the Tibet Autonomous Region, and the South-North rift areas such as Yadong, Nyalam, Chentang village, Jilong and Pulan of the South Asia channel.
DENG Hongyan
The three-dimensional model obtained by three-dimensional inversion processing of MT data completed in Qulong mining area and the inversion of MT full impedance data show the shallow three-dimensional electrical structure characteristics of 5km with strong anisotropy. The isosurface of high resistivity body in Qulong mining area shows that the high resistivity anomaly with resistivity greater than 200 Ω• m mainly reflects the distribution of intermediate acid intrusive rocks, and the low resistivity anomaly less than 200 Ω • m mainly reflects the distribution characteristics of Quaternary sedimentary strata, rhyolite and tuff of Yeba formation. Based on the resistivity structure in Qulong ore concentration area, combined with some drilling data and physical property data collected, a three-dimensional geophysical model of Qulong ore concentration area is constructed by using GOCAD software. Compared with the three-dimensional model star of Jiama ore concentration area, due to the limitation of data, the three-dimensional geophysical model of Qulong ore concentration area is slightly worse. But it is also the only three-dimensional geophysical model provided so far. The model is helpful to the development and utilization of Qulong ore concentration area.
HE Rizheng
At present, dense short-period seismic observation has become a passive source seismic observation method with fast and high-density spatial sampling, which can obtain the characteristics of velocity and interface structure under the ore concentration area. Pds-2 short period seismograph (dominant frequency: 1-2HZ) is used for multiple times. The observation is arranged inside and around the ore concentration area. The station spacing is 100m-200m-500m-1000m. The observation lasts for about 2 months. The utilization rate is 100sps or 200sps, and continuous records are made. The data format is minified, and the length of the data file is 1 hour; Pds-2 short period seismograph is powered by built-in lithium battery, which needs to work in the way of manual alternative layout. The overall layout is divided into three times, which are from June 2019 to July 2019, from September 2019 to November 2019 and from August 2020 to September 2020. The amount of data collected is about 800g, and the data completeness reaches 86%.
HE Rizheng
In this study, passive source seismology is used to systematically detect the metallogenic background of the ore concentration area. Therefore, 20 broadband seismic observation points are arranged in Jiama Qulong ore concentration area. The observation period is more than 12 months. The wide-band seismograph arranged in a plane is the integrated wide-band seismograph of nanomatrics horizon in Canada and cmg-3tde in the UK. The data format is minified. Before the actual field data acquisition, the seismometer, digital collector, GPS antenna and continuous power supply system used in the field data acquisition were tested before construction in Fuzhou City, Jiangxi Province, so as to ensure that the instrument can work normally in the field work. Most of the stations are located where the environmental interference is as small as possible to minimize the signal interference caused by human or other natural vibrations. However, due to the observation in the ore concentration area, some observation points cannot be avoided. Considering that the work area is located in Tibet, China, with strong light and large interference, in order to ensure high-quality and continuous waveform records on the basis of reducing instrument risks, we adopted the method of digging a pit to build a platform foundation, and established a platform foundation with unified specifications for each instrument. First, dig a large pit with a diameter of 80-90 cm and a depth of about 80 cm at the location where the station is to be arranged. Before digging the pit, ensure that the underground soil is the original soil rather than backfill. When digging the pit, it is best to dig the bedrock. Secondly, after the pit is excavated, arrange a prefabricated cement pier with a thickness of about 20cm and a diameter of about 30cm, then prepare a large plastic bucket with a volume of 200 L, dig holes at the bottom of the bucket, insert the bucket bottom after digging into the cement pier to the greatest extent, and then tamp it with cement or in-situ soil around the cement pier, And punch holes at the appropriate position where the barrel top is higher than the ground as the cable inlet and outlet. When the seismometer is put into the big bucket, a small bucket shall be buckled upside down on the seismometer to ensure that the seismometer is isolated from the small bucket. Finally, fill the inverted bucket and the upright bucket with high-strength sponge, stubborn. There are two advantages: first, it can isolate the seismometer and ensure the stability of internal temperature and pressure conditions; Second, it can ensure the stability of the environment in the barrel and reduce the background noise. Before installing the seismometer, the surface of the cement pier shall be dried first to ensure good contact between the supporting foot of the seismometer and the installation surface. Then use the geological compass for accurate orientation, mark the cement surface with plastic ruler, marker pen and other tools, and draw the pointing line. The pointing line should preferably pass through the center where the seismometer will be placed. After determining the orientation, place the seismometer on the drawn azimuth scale line, and rotate the seismometer to make the copper pointer at the bottom consistent with the pointing line (the copper pointer points to the East). It should be noted that the compass is easily affected by ferromagnetic objects during orientation. Therefore, the compass should be slightly away from sensors, iron tools, etc. Thirdly, connect the corresponding wire to the seismometer and wrap it around the instrument on the cement surface for several weeks. Finally, adjust the sensor foot screws to make the bubbles center and lock the screws. The broadband mobile seismic station observation adopts the continuous waveform recording method for data acquisition, the sampling rate is 100sps, and the GPS continuous signal receiving method is used for positioning, timing and clock calibration.
HE Rizheng
Tiegelongnan deposit is a large porphyry epithermal copper (gold) deposit in duolong porphyry area in the south of Qiangtang terrane in central and Western Tibet, China. The deposit is centered on the multi-stage granodiorite porphyry (GP) intrusion invading Jurassic sandstone. Phase 1 and phase 2 GP are related to biotite and sericite alteration, while phase 3 and phase 4 GP occur in the middle and shallow part of the deposit affected by sericite and high-grade argillaceous alteration (alunite kaolinite dickite pyrophyllite). Sericite alteration generally exists in the deep part of the deposit, replacing biotite alteration, and occurs porphyry chalcopyrite boron nickel pyrite ± molybdenite mineralization. The high-grade argillaceous alteration is related to the mineralization of high sulfide (marmatite, marmatite, bornite and monzonite) in the epithermal stage, superimposing sericite and biotite alteration in the shallow part of the deposit. The top of tielongnan hydrothermal system is weathered with a layer of supergene oxidation enrichment zone, which is stripped and covered by andesite and gravel. The 40Ar-39Ar age of Muscovite sampled from deep sericite alteration is 120.9 ± 0.8 Ma, which is consistent with the previously reported 40Ar-39Ar age of hydrothermal biotite 121.1 ± 0.6 Ma, molybdenite Re Os ages 121.2 ± 0.6 Ma and 119.0 ± 1.4 Ma, and GP 1 and 2 zircon U-Pb ages 121.5 ± 1.5, 120.2 ± 1.0 MA (laicp-ms results) and 118.7 ± 0.9 MA (SIMS results). The ca-id-tims zircon U-Pb age from stage 3 GP 3 is 119.9 ± 0.2 mA, which limits the age of porphyry magmatic hydrothermal events. The porphyry system was subsequently exfoliated, weathered and superimposed by discrete stages of high-grade argillaceous alteration and high sulfide mineralization. The 40Ar-39Ar ages generated by the two pulses of alunite event are 116.3 ± 0.8 Ma and 111.7 ± 1.0 Ma, respectively, representing the main epithermal alteration and mineralization ages in tielongnan. The first alunite pulse age is consistent with the younger porphyry (gp4) age of 116.2 ± 0.4 MA (zircon LA-ICP-MS age). The weathering and exhumation of porphyry epithermal deposits continued until ~ 110 Ma, and the andesite and andesite were covered with gravel. Andesite is affected by younger weak hydrothermal alteration at 108.7 ± 0.7 Ma, which is limited by the 40Ar-39Ar age of muscovite. The 40Ar-39Ar age of another barren alunite is 100.6 ± 2.0 Ma, which may represent the youngest hydrothermal event. The long-lived exothermic fluid activity of tielongnan deposit in ~ 120 ~ 100mA is consistent with the long-term tectonic magmatic event of Bangong Nujiang suture zone. The discrete epithermal metallogenic events in tiegelongan are younger than those in porphyry, which is similar to several other epithermal deposits in the world. The ~ 10 m.y exhumation history of tiegelongan is slower than the typical and rapid erosion history of ~ 1 – 2 m.y. porphyry deposits in low altitude tropical climate, and during a specific sudden uplift pulse in the Andes. The slow exhumation of tielongnan is considered to be the comprehensive result of the Cretaceous arid climate environment, relatively flat terrain and slow uplift conditions in central and Western Tibet. The experiment was entrusted to the inert gas Laboratory of the Pacific isotope and geochemistry research center of Columbia University, Canada; The data quality is good. The sample is crushed in the ring mill, washed with distilled water and ethanol, dried to - 40 + 60 mesh and sieved. Select suitable mineral particles from the bulk part. The samples were wrapped in aluminum foil and stacked in the irradiation chamber together with similar aged samples and neutron flux monitors (fish Canyon tuff Sani DIN (FCS), 28.201 ± 0.046ma). These samples were irradiated at the McMaster nuclear reactor in Hamilton, Ontario, in July 2017 at 134 MWh of the flux point in 8e. The J value error generated by the analysis of 16 neutron flux monitor positions (n = 54) is less than 0.5%.
YANG Chao , WANG Liqiang
Pusangguo is a high-grade copper polymetallic deposit dominated by skarn. It is the only large copper lead zinc cobalt nickel deposit in the Gangdise metallogenic belt (GMB); There are few records of magmatic rocks related to the deposit, and its petrogenesis and geodynamic background are not clear. In order to explore these problems, we provided zircon u – Pb ages, Hf isotope, whole rock geochemistry and Sr – nd – Pb isotope data of Busan fruit biotite granodiorite (PBG) and Busan fruit diorite porphyrite (PDP) in the deposit. Entrusted the analysis and testing center of Beijing Institute of geology of nuclear industry and the State Key Laboratory of geological process and mineral resources of China University of Geosciences (Beijing); The fresh rock samples were ground to 200 mesh without pollution for analyzing the main and trace elements and Sr nd Pb isotopic values of the whole rock. Zircon U-Pb Dating: Zircon was glued to the slide with double-sided adhesive, covered with PVC ring, and then epoxy resin and curing agent were fully mixed and injected into the PVC ring. After the resin is completely cured, the sample target is stripped from the glass slide, ground and polished, and then the sample on the target is photographed by reflected light and transmitted light under microscope and cathode fluorescence photography. According to the cathodoluminescence, reflected light and transmitted light photos of zircon, the appropriate (interested) zircon dating domain is selected. The data results are good.
LI Zhuang , WANG Liqiang
The amount of new copper predicted potential mineral resources in Jiama mining area consists of three parts: 1) the amount of new copper predicted potential mineral resources in skarn main ore body; 2) Copper in the mogulang anomaly area predicts the amount of potential mineral resources; 3) Copper in xiangbeishan anomaly area predicts the amount of potential mineral resources. The predicted resources of skarn type main ore body are mainly based on the original 334 level resources formed by extrapolation of the ore body controlled by drilling engineering. The data such as small weight and copper grade (0.72%) used in the estimation of ore body resources are consistent with the relevant ore characteristics of skarn type main ore body, and the estimation result is 1.99 million tons. The mogulang anomaly area is mainly the prospecting target area delineated by 1 ∶ 10000 rock geochemical survey in the northeast of the ore body. The target area is about 3km2. The element combination in the target area is cu-mo-w-bi-ag. The element anomaly is well combined and the content of Cu element is high. The estimated volume of porphyry copper mineralized body is 112922473.2m3, the standard of porphyry ore is 2.341t/m3, and the estimated ore volume is 264351509.8 tons. The average grade of copper in mineralized body is calculated as 0.3% of the average grade of Jiama porphyry ore body. It is calculated that the predicted potential mineral resources of copper in mogulang target area is 793000 tons. Xiangbeishan anomaly area is mainly the prospecting target area delineated by 1 ∶ 10000 rock geochemical survey in the South and west of the main ore body. The target area is about 2km2, the internal element combination is cu-mo-w-bi-ag, the element anomaly is well nested, the Cu element content is high, the estimated porphyry copper mineralization volume is 329733308.3m3, and the ore weight is small. The standard of porphyry ore is 2.341t/m3, The estimated ore volume is 771905674.8 tons. The average grade of copper in mineralized body is calculated as 0.3% of the average grade of Jiama porphyry ore body. It is calculated that the predicted amount of potential mineral resources of copper in mogulang target area is 2.316 million tons. The total estimated resources of three different ore (chemical) sections are 199 + 79.3 + 231.6 = 5.099 million tons. The quality of data results is good, and the goal of submitting the prediction of potential mineral resources of new copper is 5 million tons.
WANG Liqiang
Tiegelongnan porphyry epithermal copper (gold) deposit is located in duolong porphyry area north of Bangong Nujiang suture zone, Tibet, China. The mineralization is mainly composed of several stages of Jurassic sedimentary sandstone and diorite and granodiorite porphyry dyke, with intrusion time ranging from 123 to 116 ma. Hydrothermal alteration is characterized by alunite kaolinite dickite superimposed quartz Muscovite pyrite and biotite alteration zones. Porphyry chalcopyrite pyrite ± molybdenite (phase 1) mineralization is related to biotite alteration. The mineralization of porphyry chalcopyrite bornite (stage 2) and glauconite (stage 3) is related to quartz Muscovite pyrite alteration formed at about 121 ma. It is composed of albite porphyry (Ma-5) and chalcopyrite (Ma-5) and hydrothermal porphyry (ma-6) and chalcopyrite (ma-6) in the stage of mineralization. Fluid composition is related to Muscovite, average δ 18O is 8.9 ‰, δ D is − 56 ‰, indicating the source of magmatic water. Fluid in equilibrium with quartz vein δ 18O composition decreased from 6.7 ‰ to 2.3 ‰, which may be the result of water rock isotope exchange. Quartz fluid inclusion δ D values ranging from − 50 to − 84 ‰ are partially lower than those obtained in Muscovite alteration fluid, which may be the result of H fractionation during fluid inclusion fracture. Fluid composition balance and alunite yield in hyperthermic stage δ 18O − 1.2 to 2.7 ‰, δ D − 71 to − 51 ‰, n = 11, and δ 18O is between − 2.5 and 2.9 ‰, δ D is between − 72 and − 51 ‰ This shows that alunite and type I kaolinite are formed by the mixing of magma and high-altitude Cretaceous atmospheric precipitation. Late type II and type II III kaolinite (filled with alunite and quartz vein) fluid δ 18O and δ The D value is plotted along the mixing line between magma and low altitude Cretaceous atmospheric precipitation, which may be after erosion and plateau subsidence. Porphyry mineralized sulfide phase 1 chalcopyrite and pyrite δ 34S value is between − 5.8 and 0.9 ‰, and the average fluid δ 34sh2s = − 2.5 ‰ (n = 10), while chalcopyrite in stage 2 ranges from − 8.7 to − 3 ‰, with an average of δ 34SH2S=−5.6‰（n=5）。 Sulfide phase 2 fluid δ 34sh2s value is lower than stage 1, indicating that chalcopyrite bornite mineralization was formed under higher oxidation conditions than chalcopyrite pyrite mineralization. Alunite δ The 34S value is between 11 and 18.3 ‰ (n = 8), and the associated sulfide is grade 4 pyrite δ 34S values range from − 32.2 to 5.4 ‰. The S isotope imbalance in alunite pyrite pairs may be due to the rapid cooling and retrograde S isotope exchange during the late sulfide emplacement. Epithermally mineralized sulfide stage 4 s equilibrium pyrite (− 14.9 to − 9.5 ‰), stage 5 chalcopyrite (− 11.6 to − 8.2 ‰) and stage 6 (− 5.4 to − 2.6 ‰) show δ The increase of 34S value indicates that the composition of epithermal fluid evolves to more reduction conditions. The experiment was entrusted to the Queen's isotope research center of Queen's University of Canada and the microanalysis Laboratory of Memorial University of Canada. The experimental data are of good quality. Representative core samples were collected from the East-West section and several other boreholes. Separate biotite (n = 1), white mica (n = 5), quartz (n = 13), alunite (n = 10) and kaolinite (n = 12) for O and H isotopic analysis, and separate alunite (n = 10), pyrite (n = 5) and chalcopyrite (n = 4) for S isotopic analysis of conventional minerals; Eight polished slices were prepared for in-situ sulfur isotope analysis of pyrite (n = 16) and chalcopyrite (n = 10).
YANG Chao , WANG Liqiang
Demingding is a less studied post collisional porphyry copper molybdenum deposit, which is located in the east of Gangdise porphyry copper belt. This paper provides LA-ICP-MS zircon U-Pb dating, whole rock geochemistry and zircon trace element data of biotite porphyry in Deming top. Zircon U-Pb dating shows that the weighted average 206 Pb / 238 u age of Miocene biotite porphyry is 20.36 ± 0.46ma (mswd = 2.6, n = 21). Miocene biotite porphyry has high SiO_ 2、K_ 2O and Al_ 2O_ 3, and shows characteristics similar to adakite. These rocks have high Sr / y ratio and fractionated REE mode with low hree abundance. Compared with HFSE, they are enriched in lile with (87 Sr / 86 SR) I value of 0.7059 ~ 0.7062, ε Nd (T) value is − 2.35 ~ − 1.67, and (- 206 Pb / 204 Pb) I value is 18.50 ~ 18.55. These characteristics are similar to other Miocene adakitic intrusive rocks in the Gangdise belt. We believe that biotite porphyry has the same petrogenesis as other Miocene ore bearing intrusive rocks in the eastern Gangdise belt. Its genesis comes from the mixing of subduction transformation, remelting of metamorphic lower crust of Tibet and hydrated mafic magma metasomatizing the mantle of Tibet. Zircon in biotite porphyry has only very small negative Eu anomaly (Eun / Eun * > 0.3), with large Ce ~ (4 +) / Ce ~ (3 +) ratio (average 113), 10000 ~ * (Eun / Eun *) / Y (3.94 ~ 8.14 > 1), CE / Nd (9-58, average 30), (CE / nd) / Y (0.008 ~ 0.127 > 0.003), dy / Yb (0.15-0.24, < 1); 0.3), indicating that biotite porphyry has relative hydration and oxidation. Therefore, biotite porphyry is considered to be a relatively enriched intrusion with certain exploration potential. Data source: entrusted the Institute of mineral resources, Chinese Academy of Geological Sciences and the State Key Laboratory of geological process and mineral resources, China University of Geosciences (Beijing). The data results are good.
ZHANG Zebin , WANG Liqiang
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