Brief Introduction: Second Tibetan Plateau Scientific Expedition Program
Number of Datasets: 305
This data is a histogram of red coral stratum in Kunlun mountain area, including the characteristic elements of stratum thickness and lithology change, which is based on detailed field survey and indoor analysis. The specific processing method is as follows: through field investigation, obtain the material of formation lithology composition, formation thickness, structural characteristics, etc., and draw the draft of stratigraphic histogram by hand. Back in the room, the lithology of rock is confirmed by thin section identification, and then the histogram is electronized by CorelDRAW software. This map is about 4MB in size with high resolution. It can be used for stratigraphic investigation, lithological analysis, the highest marine strata in Kunlun Mountain, paleontology and paleogeography.
2021-06-23 169 0
This dataset mainly comprises whole-rock major and trace element contents (from the Baigang ophiolite of the central YZO; Tables 1&2), platinum group element (PGE) abundances and Re-Os isotopic compositions (Table 3) of the Yarlung-Zangbo suture zone (YZO) ophiolitic peridotites in southern Tibet (China). All analyses were analyzed conducted at State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences (Beijing). Whole-rock major element compositions were determined by an inductively coupled plasma optical emission spectrometer (ICP-OES) and the analytical precision is 1–3%; Whole-rock trace element concentrations were analyzed by a quadrupole inductively coupled plasma mass spectrometer (Q-ICP-MS) using external calibration and Rh as an internal standard. The analytical accuracy was generally better than 5% within the accepted values; (3) Whole-rock HSE abundance and Re-Os isotope analyses were conducted using an isotope dilution technique coupled with Carius tube aqua regia digestion. Osmium concentrations and isotopic compositions were determined by negative thermal ionization mass spectrometry (N-TIMS), all other HSE abundances were measured by high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). The accuracy of PGE analysis (2SD) was better than 5%, and that of Os isotope analysis (2SD) was better than 0.5 ‰. The repeated analyzed values of the UB-N, an international reference meterial, are identical within uncertainties to the recommended values. The data have been published in Geochimica et Cosmochimica Acta (Xu, Y., Liu, J.*, Xiong, Q., Su, B.-X., Scott, J. M., Xu, B.,Zhu, D.-C., Pearson, D. G. (2020). The complex life cycle of oceanic lithosphere: A study of Yarlung-Zangbo Ophiolitic Peridotites, Tibet. Geochimica et Cosmochimica Acta 277, 175-191). The main results are as follows: (1) Platinum group elements (Pd/Ir, Pt/Ir) are systematically decoupling from lithophile elements (e.g., Al2O3), while there is a positive correlation between Pd/Ir ratios and chalcophile elements (e.g., Cu). Combined with sulfide observation, it is confirmed that a BMS-rich melt metasomatism occurred in the YZO mantle after melt extraction. It is speculated that the metasomatic agent may be S-saturated forearc basaltic magmas, rather than S-undersaturated boninitic magmas; (2) There is no covariant relationship between Pd/Ir and 187Os/188Os, indicating that the influence of recent melt metasomatism on the Os isotopic composition of peridotite is limited. The simulation of mixing between the convective upper mantle and the oldest ophiolitic peridotite shows that the YZO mantle source region experienced a systematic melt extraction process after two end-member mixing; (3) Re-depleted Os model ages (TRD) indicates that the YZO mantle is heterogeneous at ~1000 km scale, and some old mantle domains (up to 2.2 Ga) are recycled into the Mesozoic Neo-Tethyan oceanic mantle (187Os/188Os peak: 0.126). The above data set illustrates the complex life cycle of the oceanic lithosphere and builds a relationship between plate tectonics and mantle evolution, which is of great significance for exploring the geodynamic mechanisms that control the composition and evolution of the Earth's upper mantle. In addition, this data set can provide a comparative reference for the study of whole-rock platinum group elements and Re-Os isotopes of peridotites and chromitites in the Bangong-Nujiang ophiolitic belt, which is of great scientific value for the systematic study of chromite mineralization and formation of Cr-PGE ore deposits.
2021-06-23 391 14
The growth process of the Tibetan Plateau has always been the focus of debate at home and abroad, which is of great significance for evaluating different growth models. In recent years, one of the focuses of debate is whether the "original Tibetan Plateau" exists and its scope. Sedimentological evidence and provenance analysis show that the topographic growth occurred in Qiangtang terrane and North Lhasa terrane as early as Cretaceous. However, paleontological and PALEOELEVATION evidences show that the topographical height of the central part of the plateau was formed in the Eocene Miocene. In order to solve this problem, we conducted apatite fission track studies in the Qiangtang terrane in the hinterland of the Qinghai Tibet Plateau. Because crustal thickening usually leads to topographic uplift and relief changes, thus accelerating denudation, the cooling events recorded by fission track are often strong indirect evidence of crustal thickening. The median apatite fission track age of Mesozoic sandstone samples is 40.1 ± 2.6 to 129 ± 3 Ma, with peak ages of ~ 45 Ma and 100-120 ma; The fission track age of the Eocene granite is 38.3 ± 1.3 Ma and 27.4 Ma respectively ± 1.6 Ma。 The uncorrected closed track length is 9.26 ± 39 to 14.11 ± zero point two four μ m. The corresponding relationship between age and age presents a typical "boomerang" trend, which reveals that the regional cooling time is earlier than 100 mA. The results of hefty thermal history inversion reveal that the growth process of the central part of the plateau can be divided into two stages: the first stage, the early Cretaceous (140-100 MA) cooling process reveals the crustal thickening in the central part of the plateau, which may be caused by the horizontal subduction of Bangong Nujiang Tethys ocean. At this time, the prototype of the plateau was formed in the middle and south of Qiangtang terrane; In the second stage, the former Tibet Plateau was gradually formed in the middle of the plateau from Eocene to Oligocene. The spatial distribution characteristics of Cenozoic low temperature thermochronology data in the central plateau show that there is no obvious East-West change, so the lower crustal flow model may be difficult to explain the growth process of the central plateau. On the contrary, the discrete and uniform distribution pattern of low temperature thermochronology data is consistent with the model of continental subduction and lithospheric mantle delamination. Combined with the regional deformation characteristics, the formation mechanism of the former Tibet Plateau includes upper crust shortening, continental crust subduction and deep mantle delamination.
2021-06-21 233 5
The data set includes the sampling location information of 5 main stream samples and 9 tributary samples (Table 1), the whole sand petrographic information (Table 2) and heavy mineral component information (Table 3) of the Nianchu River sands. The information of total sand components is analyzed by using Gazzi-Dickinson method on 63-2000μm sand under the microscopic identification; Heavy minerals are produced from 32-500μ sand by using heavy liquid and liquid nitrogen, and the heavy mineral components were identified by their optical properties and Raman spectra. The data were collected in the laboratory of provenance analysis at the University of Milano-Bicocca, which has a high quality and credibility. The data set reflects the sediment composition of different tectonic units (Tethys Himalaya, ophiolitic suture, Kangma dome and High Himalaya) drained by the Nianchu river, and can be used to calculate the various sediment contributions of different tectonic units.
2021-06-20 166 4
Modern solid sediments are widely distributed in the Yarlung Zangbo River Basin, including different types of river sediments in different sedimentary environments. In this scientific research, we have carried out a detailed field geological investigation on the sand in the main stream of the Yarlung Zangbo River and about 100 tributaries in China. More than 150 solid sediment sites were investigated during this scientific research. In each site, not only field information, sedimentary description and photos were collected, but also river sand sample was collected systematically. Studying the composition and distribution characteristics of solid sediments in Yajiang river basin is of great scientific and social value for revealing the source-to-sink process and evolution of river system, soil and water conservation, early warning and prevention of natural disasters, and major infrastructure construction.
2021-06-20 168 0
This dataset shows the high-resolution inorganic carbon isotopes of the lower part of the upper Triassic Bolila Bagong formation in Quemocuo area, Qiangtang basin, Qinghai Tibet Plateau（（ δ 13C CARB) and organic carbon isotope（ δ 13 Corg) records and mineralogical data. The samples were collected from the lower part of the upper Triassic Bolila Bagong formation in Quemocuo area, Qiangtang basin. Zircon U-Pb dating was performed by la-mc-icp-ms using the method of Hou Kejun et al. (2009). The results are as follows: the maximum sedimentary age of detrital zircon in calcareous fine sandstone of Bagong formation is 232.5 ± 3 Ma, combined with previous biostratigraphic studies such as ammonoids and bivalves, the stratigraphic age of the Bagong formation is classified as Carnian. In this section, the supply of siliciclastics increased and the contents of calcite and illite decreased sharply, indicating that the paleoclimate changed from drought to warm and humid during CPE. In this section, inorganic carbon isotope（（ δ 13C CARB) and organic carbon isotope（ δ This may be related to the disturbance of global carbon cycle and the release of carbon dioxide rich in 12C. At the beginning of CPE, the degree of negative C isotope bias in Quemocuo area is lighter than that in other areas. During the same period, the eruption of wrangellia igneous province and the release of methane were the main causes δ The most likely reason for the significant negative shift of 13C.
2021-06-20 229 6
Residual bay basin was developed during the transition from marine to continental deposition in the Qiangtang Basin. This transition environment enables Qiangtang Basin to generate organic-rich shales. The mechanism of organic matter accumulation is still controversial due to its complicated organism origin. In this study, we choose residual bay organic-rich shales from the Changliang Mountain section to study the mechanism of organic material accumulation. Redox-sensitive indices including EF values, Mn contents and U/Th ratios reveal that the water volume was dyoxic to anoxic condition during the shale deposition. The relatively low primary productivity during deposition is supported by the relatively low biogenic barium concentrations. Climate change indices including oxygen-isotope, Mg/Ca and Fe/Mn ratio show that a significant climatic change has taken place during the shale deposition. Climate has changed into warm and humid during the shale deposition compared with dry and cold during underlying marl deposition. Combined with sedimentary rate and type II kerogen, this paper proposed that warm and humid climate conditions, relatively high sedimentation rate, and high input from terrigenous higher plants are the main factors controlling organic matter accumulation in the Changliang Mountain shales.
2021-06-20 154 5
The samples are well qiangke-1, well qiangdi-17 and well qiangzi-16. The analysis and testing work was completed in the laboratory of AR, u-th-he geochronology, Institute of Geology and Geophysics, Chinese Academy of Sciences. See Wu Lin et al. (2016) for testing methods. The results are as follows: the zircon (U-Th) / He ages of 9 samples from three boreholes in the Qiangtang block in the Qinghai Tibet Plateau, except that the thermal history information of two samples from Eocene has not been reset, the rest of the samples are concentrated in Cretaceous, and the age values change little with elevation, indicating the existence of Cretaceous denudation cooling. Well qd-17 in the west of the Qiangtang block recorded denudation cooling in the early Cretaceous (about 127-114 MA), and well qz-16 in the East recorded denudation cooling in the late Cretaceous (about 92-64 MA). The denudation and cooling of the Cretaceous resulted in the statistics of regional low temperature thermochronology and the response of tectonic sedimentary events. The low-temperature thermochronological data of the Qiangtang block, Lhasa block and Himalayan block show that the Cretaceous early Eocene low-temperature thermochronological ages are widely distributed in the Northern Lhasa block and Qiangtang block (within the plateau), while the late Miocene low-temperature thermochronological ages are widely distributed in the southern Lhasa block to Himalayan block (southern margin of the plateau), This age distribution pattern suggests that the interior and southern margin of the plateau experienced different erosion cooling histories. Referring to the rapid denudation cooling process in the southern margin of the plateau since late Miocene, it is speculated that there was a Cretaceous rapid denudation cooling event in the interior of the plateau. Early Cretaceous depositional discontinuities and unconformities occurred widely in the Northern Lhasa block, Qiangtang block and its northern area, which also indicated rapid denudation during Cretaceous. Combined with the analysis of regional tectonic evolution, the Cretaceous denudation cooling may be the result of the collision between the Lhasa block and Qiangtang block after the closure of the Bangong Lake Nujiang ocean in Early Cretaceous, which indicates that there may have been obvious shortening, thickening deformation and corresponding denudation cooling in the crust of the plateau before the Cenozoic India Eurasia collision.
2021-06-19 210 5
The dataset is the 30 meter resolution leaf area index (LAI) product from 2010 to 2019 over the Tibetan Plateau. The LAI product was retrieved using Landsat time series data and physically based radiative transfer model, and it is the annual maximum synthetic leaf area index product. When validated with the simulation data set, the root-mean-square error (RMSE) was 1.16. Leaf area index highly integrates the horizontal coverage and vertical structure of vegetation, and is an important structural parameter of the vegetation canopy, which can provide data product support for the research and applications in land surface process simulation, resources survey, ecological environment monitoring, global change research and other fields.
2021-06-18 256 20
Data content: The data set products include impervious surface products with a resolution of 30 meters in the Qinghai-Tibet Plateau, which can be used as a key parameter for related research on the Qinghai-Tibet Plateau ecosystem. Data source and processing method: Product inversion is mainly based on Landsat series data, considering joint features, combining depth spatial features, long-time NDVI and other exponential features, and topographic features, and using random forest model to achieve impervious surface information extraction. Data quality: The overall accuracy is high, better than 80% in most areas. Data application results and prospects: The data set will be continuously updated and can be used to further clarify the impact of human activities on the ecosystem of the Qinghai-Tibet Plateau.
2021-06-18 180 8
Data content: The data set products include impervious surface products with a resolution of 10 meters in the Qinghai-Tibet Plateau, which can be used as a key parameter for related research on the Qinghai-Tibet Plateau ecosystem. Data source and processing method: Product inversion is mainly based on Sentinel series data, considering joint features, combining depth spatial features, long-time NDVI and other exponential features, and topographic features, and using random forest model to achieve impervious surface information extraction. Data quality: The overall accuracy is high. Data application results and prospects: The data set will be continuously updated and can be used to further clarify the impact of human activities on the ecosystem of the Qinghai-Tibet Plateau.
2021-06-18 214 9
This dataset includes daily minimum temperature (Tmin), maximum temperature (Tmax) and precipitation (PPT) data of NEX-GDDP (NASA Earth Exchange Global Daily Downscaled Projections) (v1.0) over the periods of 2000–2009 and 2090–2099. The unit of Tmax and Tmin is K, and the unit of PPT is kgm-2s-1; the background filling value is -999. This dataset is a subset extraction fromthe original data. The original data was downloaded from https://portal.nccs.nasa.gov/datashare/NEXGDDP/BCSD/ in August 2020; The NEX-GDDP data set is obtained from CMIP5 (Coupled Model Intercomparison Project Phase 5) historical climate and General Circulation Models (General Circulation Models) operating in RCP (Representative Concentration Pathways) 4.5 scenario mode, including 21 atmospheric circulation models; among them, 2000 –2005 is a historical climate scenario, and 2006–2009 and 2090-2099 are RCP 4.5 scenarios. For the description of the original data, please refer to https://www.nccs.nasa.gov/services/data-collections/land-based-products/nex-gddp.
2021-06-18 191 0
The data set includes county-level demographic data of 252 areas in Qinghai-Tibet Plateau in 1982, 1990, 2000, 2010 and 2018, and GDP data in 1988, 1995, 2000, 2010 and 2015. The demographic data includes registered population, resident population, urban population, rural population, male population, female population and non-agricultural population. GDP data includes total GDP output value and GDP output value of primary, secondary and tertiary industries. The data are helpful to study the impact of human activities on the ecological climate of Qinghai-Tibet Plateau, and to explore the urbanization development, urban and rural population mobility, resident population change, local birth rate and agricultural population change in Qinghai-Tibet Plateau. The data were obtained by contacting the local statistics bureau, relevant statistical yearbooks and annual statistical bulletins of various places during the second scientific investigation of Qinghai-Tibet Plateau.
2021-06-18 278 0
The data set records the output information of main crops in Qinghai Province from 1978 to 2016, mainly including grain, oil, fruit, meat and eggs and main industrial products, aluminum, crude oil, steel, cement and power generation. The data set contains three data tables (1. The data table of main industrial and agricultural products per capita has 17 fields; 2. The data table of crop production by counties has 13 fields; 3. The data table of main industrial and agricultural products per capita and main agricultural products. There are 6 fields in total). The data comes from: "Qinghai Social and Economic Statistical Yearbook" and "Qinghai Statistical Yearbook", with the same precision as the statistical yearbook extracted from the data. This data set is of great value for studying food security and agricultural production in Qinghai Province.
2021-06-18 203 0
The data set records the basic information of cultivated land in the Tibet Autonomous Region and contains two data tables. Among them, the data table 1 has 7 fields, and the data table has 5 fields, respectively recording the cultivated land area, dry land area, paddy field area, effective irrigation area, and national infrastructure area of Tibet Autonomous Region and each district and county from 1959 to 2016. , The units are all hectares. The data comes from: "Tibet Statistical Yearbook" and "Tibetan Social and Economic Statistical Yearbook", with the same accuracy as the statistical yearbook extracted from the data. This data set has important value for understanding the situation of cultivated land in the Tibet Autonomous Region, evaluating the level of cultivated land utilization, and researching agricultural production and food security.
2021-06-18 186 0
The dataset is the 30m resolution burned area product from 1980s to 2019 over the Tibetan Plateau. The dataset is produced using Landsat time series land surface reflectance and machine learning algorithm, and the overall accuracy is over 90%. It can provide data product support for the research and applications in fire monitoring, carbon emission studies, ecological environment monitoring, global change research and other fields.
2021-06-17 50 1
Aboveground biomass (AGB) is an important indicator for measuring ecosystem productivity.This dataset provides the forest aboveground biomass with a resolution of 30m in the Qinghai-Tibet Plateau from 1970s-2022. The biomass data is estimated using Landsat series data, based on actual ground data and some literature data, tree height data, and forest types including coniferous forest, broad-leaved forest and mixed forest.Through data disclosure and free download services, it provides basic data support for related research on the dynamic changes of forest ecosystems on the Qinghai-Tibet Plateau, and also provides a scientific basis for sustainable forest management in this region.
2021-06-17 56 1
Reasonable carrying capacity, also known as theoretical carrying capacity, refers to the maximum number of domestic animals that can be carried by a certain grassland area in a certain period of time under the premise of moderate grazing (or mowing) and maintaining sustainable production of grassland to meet the needs of normal growth, reproduction and production of livestock. Based on the MODIS inversion data of forage yield (fresh weight, kg / hm2), the reasonable carrying capacity of grassland (sheep unit, mu / km2) was evaluated according to the code for calculation of grassland carrying capacity and grass livestock balance (DB 51 / t1480-2012) and calculation of reasonable carrying capacity of natural grassland (NY / T 635-2015), The time series is 2000-2019, and the spatial resolution is 250m. This data set can analyze the temporal and spatial variation characteristics of the theoretical carrying capacity under the condition of rational utilization of grassland in the Qinghai Tibet Plateau, evaluate the carrying capacity characteristics of grassland in the Qinghai Tibet Plateau, and extract the overgrazing areas, which has important application value for ecological protection, monitoring and early warning of the Qinghai Tibet Plateau.
2021-06-17 122 0
Grassland yield is an important ecological parameter of grassland, which is an important basis for monitoring grassland productivity, Estimating Grassland reasonable carrying capacity and evaluating grassland carrying status. Based on the grassland data collected in July and August, MODIS NDVI, precipitation and terrain parameters, multivariate statistical equations were established to invert the total grass yield (kg / hm2) and edible grass yield (kg / hm2). The time series is 2000-2019, and the spatial resolution is 250 meters. Based on the data of 50 quadrats distributed in Sichuan, Tibet, Qinghai, Gansu and other regions, the results show that the average absolute error of total grass yield is 734.75kg/hm2, and the average relative error is 24.85%. The average absolute error of edible grass yield is 715.81kg/hm2, and the average relative error is 30.52%. Due to the complexity of grassland types, high spatial heterogeneity and scale mismatch between the measured grassland quadrats and MODIS image pixels, this accuracy can meet the requirements of remote sensing monitoring of grassland in large areas. This data set can analyze the spatiotemporal variation characteristics of grassland productivity in the Qinghai Tibet Plateau, evaluate the carrying capacity characteristics of grassland in the Qinghai Tibet Plateau, and extract the overgrazing areas, which has important application value for ecological protection, monitoring and early warning of the Qinghai Tibet Plateau.
2021-06-17 114 0
The actual carrying capacity refers to the number of livestock in a certain area of grassland in a certain period of time. The actual carrying capacity is obtained from the statistical yearbooks of the provinces (autonomous regions) and cities (prefectures) of the Qinghai Tibet Plateau and the statistical data provided by the animal husbandry management departments. In the statistical data, there are a variety of statistical dimensions, such as the number of stocks on hand, the number of stocks on hand, the ratio of stocks on hand, and the number of livestock at the end of the year, etc. Based on the multivariate linear regression between the actual livestock carrying capacity and population density, NPP and topographic relief in the statistical yearbook, the spatial model of actual livestock carrying capacity was established, and the grid data of actual livestock carrying capacity (sheep unit, mu / km2) was obtained. The time series was from 2000 to 2019, and the spatial resolution was 250 meters. Using the statistical data of Guoluo, Yushu, Changdu, Naqu, ABA, Ganzi and Gannan in the core pastoral areas of the Qinghai Tibet Plateau, the results show that the average absolute error of spatialization is 27.48 mu / km2, and the average relative error is 13.79%. This data set can analyze the temporal and spatial variation characteristics of the actual livestock carrying capacity of the Qinghai Tibet Plateau, evaluate the grassland carrying capacity characteristics of the Qinghai Tibet Plateau, and extract the overgrazing areas, which has important application value for ecological protection, monitoring and early warning of the Qinghai Tibet Plateau.
2021-06-17 396 0