Debris flow in Nanfeng area is a natural disaster phenomenon caused by the combination of many natural factors. It is affected by the terrain, geology and climate. Therefore, the formation and development of debris flow fully reflect the organic combination of various natural factors. The modern geomorphic process in Nanfeng area is very active, and the glaciation, canyon flow and slope physical and geological processes are very strong. The data analysis shows that due to the sharp rise of the ground and the strong invasion of the Yarlung Zangbo River water system, most of the gullies are V-shaped, short and steep, and the vertical gradient of the gully bed is large, about 500 ‰ in the upper reaches and about 400 ‰ on average, and 250-300 ‰ in the middle and lower reaches. This kind of steep valley terrain is easy to form debris flow under the action of turbulent current. Under the action of gravity, landslides and collapses occur continuously in the valley. According to the investigation, most of the terrain slopes favorable for the formation of debris flow in Nanfeng area are above 30 degrees, and the upper valley slope in this area can generally reach 40-50 degrees, and the maximum can reach 60-70 degrees. The middle and lower valley slopes are also between 35-40 degrees, which are favorable for the development of debris flow.
PENG Buzhuo, YANG Yichou
Lithofacies analysis is an important research method to explore the source region, background, and nature of sedimentary basins. Through the systematic investigation of several late Cretaceous strata in Nepal, situated on the south flank of the Himalayas, the Tulsipur and Butwal sections conducted detailed lithology and sedimentary facies analysis. Continuous strata include the Taltang Fm. , Amile Fm. , Bhainskati Fm. and Dumri Fm. from bottom to top. The lithology contains terrigenous clastic rocks such as conglomerate, sandstone, siltstone and mudstone, chemical rocks such as limestone and siliceous rock, as well as special lithology such as coal seam, carbonaceous layer and oxidation crust. Both sections have various colors and sedimentary structures, which are good materials for the analysis of lithofacies evolution. According to the characteristics of lithofacies and sedimentary assemblage revealed that the Nepal sedimentary environment evolution during the late Cretaceous, which experienced the marine, fluvial, lacustrine, and delta evolution process.
Guided by the theory of plate tectonics, paleogeography, petroliferous basin analysis and sedimentary basin dynamics, we have collected a large number of data and achievements of geological research and petroleum geology in recent years, including strata, sedimentation, paleontology, paleogeography, paleoenvironment, paleoclimate, structure, oil and gas (potash) geology and other basic materials, especially paleomagnetism, Paleogene Based on the data of detrital zircon and geochemistry, combined with the results of typical measured stratigraphic sections, the lithofacies and climate paleogeographic pattern of Cretaceous were restored and reconstructed, and two lithofacies paleogeographic maps of early and late Cretaceous of Pan tertiary and two climate paleogeographic maps of early and late Cretaceous of Pan tertiary were obtained, aiming at discussing the influence of paleogeography, paleostructure and paleoclimate In order to reveal the geological conditions and resource distribution of oil and gas formation, and provide scientific basis and technical support for China's overseas and domestic oil and gas exploration deployment.
This data set includes apatite and zircon (U-Th) / He ages, apatite fission-track (AFT) ages of the Yalong River thrust belt, which will be continuously updated in the future. The first part is the apatite and zircon He and apatite fission-track data from the Yunongxi fault, a branch fault in the hinterland of the Yalong River thrust belt. The second part of the data is from the Jinping Shan-Muli fault, a branch of the Yalong River thrust belt, including apatite and zircon He ages data. The data results are concentrated, which well constrain the evolution of the Yalong River thrust belt and provide a high-quality chronological basis for exploring its role in the process of plateau expansion.
The data set of hydrogeological elements in the typical frozen soil area of Qilian Mountain mainly includes groundwater type, water richness (single water inflow or single spring flow), main rivers and tributaries, spring water (falling springs, spring groups, large springs, Mineral spring distribution), borehole (pressure water borehole, submerged borehole, gravity flow borehole distribution), fault zone (compressive fracture, tensile fracture), angle unconformity boundary, parallel unconformity boundary, west branch of upper Heihe River The boundary of the watershed, the seasonal frozen soil area and the permafrost distinguish the boundary, the distribution of modern glaciers and swamps. This data set of hydrogeological elements can provide background information for the hydrological ecological process and hydrogeological environment in cold regions. This data comes from the vectorization of four 1: 200,000 hydrogeological maps (Qilian, Yenigou, Qilian, and Sunan) and reintegrates the groundwater types. With higher resolution, the data can provide background information for the research on the evolution of water and soil resources and environmental changes in the source area of the Pan-Third Pole River.
This data set is from the paper: Ding, L., Spicer, R.A., Yang, J., Xu, Q., Cai, F.L., Li, S., Lai, q.z., Wang, H.Q., Spicer, t.e.v., Yue, Y.H., Shukla, A., Srivastava, g., Khan, M.A., BERA, S., and Mehrotra, R. 2017. Quantifying the rise of the Himalaya origin and implications for the South Asian monsoon. Geography, 45:215-218. This achievement is part of a series of research results of paleoaltitude carried out by Ding Lin' team. We reconstruct the rise of a segment of the southern flank of the Himalaya-Tibet orogen, to the south of the Lhasa terrane, using a paleoaltimeter based on paleoenthalpy encoded in fossil leaves from two new assemblages in southern Tibet (Liuqu and Qiabulin) and four previously known floras from the Himalaya foreland basin. U-Pb dating of zircons constrains the Liuqu flora to the latest Paleocene (ca. 56 Ma) and the Qiabulin flora to the earliest Miocene (21–19 Ma). The proto-Himalaya grew slowly against a high (~4 km) proto–Tibetan Plateau from ~1 km in the late Paleocene to ~2.3 km at the beginning of the Miocene, and achieved at least ~5.5 km by ca. 15 Ma. Contrasting precipitation patterns between the Himalaya-Tibet edifice and the Himalaya foreland basin for the past ~56 m.y. show progressive drying across southern Tibet, seemingly linked to the uplift of the Himalaya orogen.
We compiled the Seismotectonic Map of Western Asia using the ArcGIS platform through data collecting and digitization. The seismotectonic map of Western Asia covers Iran and its surrounding countries and regions. Based on the “Major active faults of Iran” map, the seismotectonic map is replenished with massive published data and depicts the location and nature of the seisogenic faults or active faults and the epicenter of earthquakes with M ≥ 5 from 1960 to 2019. The map can not only be used in the research of active faults and seismic risks in Western Asia, but also will be applied to the seismic safety evaluation for infrastructure construction.
The Pan-Third Polar region has strong seismic activity, which is driven by the subduction and collision of the Indian plate, the Arab plate and the Eurasian plate. 18806 earthquakes with Magnitude 5 or larger have occurred in Pan-Third Polar region (north latitude 0-56 degrees and east longitude 43-139 degrees) since 1960. Among them, 4 earthquakes with Magnitude 8 or larger, 187 earthquakes with Magnitude 7.0-7.9， 1625 earthquakes with Magnitude 6.0-6.9 and 16990 earthquakes with Magnitude 5.0-5.9 have occurred. Earthquakes occurred mainly in the foothills of the India-Myanmar Mountains, the Himalaya Mountains, the Sulaiman Mountains, where the India Plate collided with the Eurasian plate, and the Zagros Mountains where the Arab plate collided with the Eurasian plate.
Guided by the theories of plate tectonics, paleogeography, petroliferous basin analysis and sedimentary basin dynamics, we have collected a large number of data and achievements of geological research and oil-gas geological research in Pan third pole in recent years, including basic materials such as stratum, sedimentation, paleontology, paleogeography, paleoenvironment, paleoclimate, structure, oil-gas (potash) geology, especially paleomagnetism and paleogenesis On the basis of zircon and geochemical data, combined with the results of typical measured stratigraphic sections, the lithofacies and climate palaeogeographic pattern of Jurassic period are restored and reconstructed, and the paleogeographic map of lithofacies and climate of Pan third extremely early, middle and late Jurassic (3 sheets) and pan third extremely early, middle and late Jurassic (3 sheets) are obtained, aiming to discuss paleogeography and paleostructure The control and influence of paleoclimate on oil and gas (including potash) resources, in order to reveal the geological conditions and resource distribution rules of oil and gas formation, and provide scientific basis and technical support for overseas and domestic oil and gas exploration and deployment in China.
Paleomagnetism has played an important role in quantifying the Mesozoic evolution of “Proto-Tibet”. We present here our recent paleomagnetic data from five Middle-Upper Jurassic sedimentary sequences of the eastern North Qiangtang Terrane at Yanshiping. The new paleomagnetic results from 99 sites, 1,702 samples and reveal paleopoles at 79.1°N/306.9°E (dp=3.9°, dm=6.3°) for Quemo Co Fm, 68.9°N/313.8°E (dp=2.1°, dm=3.7°) for Buqu Fm, 66.1°N/332.1°E (dp=2.7°, dm=4.6°) for Xiali Fm, 72.4°N/318.6°E (dp=3.9°, dm=6.7°) for Suowa Fm, and 76.9°N/301.1°E (dp=7.9°, dm=13.2°) for Xueshan Fm, respectively. These results indicate that Yanshiping experienced latitudinal changes from ~24.5° N to ~22.0º N over the time interval 171.2 - <157.5 Ma, accompanied by clockwise (CW) rotations of ~19.8±9.4º between ~171.2 and 161.7 Ma and counterclockwise (CCW) rotations of ~15.4±13.4º between ~161.7 and <157.2 Ma. We attribute the change in rotation sense at approximately ~161.7 Ma to the initial collision of the Lhasa and Qiangtang terranes. Using this and other paleomagnetic data from the Lhasa, Qiangtang and Tarim terranes, as well as other geological evidence, such as tectonism-related sedimentary sequences, volcanism, and HP metamorphism, we propose a new conceptual evolution model for the Mesozoic QT and Tethyan Oceans, including 3 intra-continental collisions (South-North Qiangtang, Qiangtang-Songpan-Ganzi and Lhasa-Qiangtang) and post collisional extensions.
The landform information integration in western China was completed by a team led by Dr. Xie chuanjie, from the institute of geography, resources and environment, Chinese academy of sciences.It includes 1:400,000 national geomorphologic database and 1:100,000 western geomorphologic database. 1:400,000 geomorphologic data are "China geomorphologic map (1:400,000)" edited by LI Bingyuan and "China and its adjacent areas geomorphologic map (1:400,000)" edited by CHEN Zhiming. Scan and register the data, vectorize all the registered maps by using ArcMap software, and establish their own classification and code system. According to map spots (common staining) and symbols, geomorphic types are divided into basic geomorphic types and morphological structure types (points, lines and planes). 1:1000000 western geomorphic data is integrated and updated by digital geomorphology based on multi-source data such as remote sensing image and adopts hierarchical interpretation method.Plains and mountains;Primary geomorphic types (25 types),10 genetic types: secondary genetic types: subdivision of morphological differences. The type of geomorphic material whose composition or lithology is determined. Conducted among 16 landscape points of interpretation work, their Numbers are: 45 (Kathmandu), G - G - 46 (the) wrong, H - 44 (pli), 45 (xigaze), H - H - 46 (Lhasa), H - 47 (qamdo), 43 (Islamabad), I - I - 44 (lion spring river), 45 (change), I - I - (amdo) 46, 47 (yushu), J - I - 43 (kashi) (wada), J, J - 44-45 (JuMo), 46 (golmud), J J - - 47 (xining)
ZHOU Chenghu, CHENG Weiming
This data set comprises pictures of geological sections and landscape of Nima Basin and Lunpola Basin in the north of Tibetan Plateau which produced on achievement of geological survey in these years. The process of section pictures drawing comprises: measurement of different stratas by hand; identify and description of stratas by experienced geological researcher; picture production with software, based on information collected above. Landscape pictures were drew from satellite maps as base map, then added texts with software. All the pictures are clear, detailed and comprehensive. They are very critical for research on geology, geomorphology of the important localities in the north of Tibetan Plateau, such as Nima Basin and Lunpola Basin, and necessary for paleo-altimetry and uplift of Tibetan Plateau.
The data set is the distribution of the average roughness in Central Asia including three temperate deserts, the Karakum, Kyzylkum and Muyunkun Deserts, and one of the world's largest arid zones. This is the MODIS-NDVI data set calculated by using the median particle diameter and the vegetation coverage. The space and time resolutions are 500 m and 16 days, respectively. The time is from 01, January, 2017 to 18, December, 2017. The data set uses the the Geodetic coordinate system. It can be used for the investigation of the Desert oil and gas field, and oasis cities.
The Southern Tibet Rift System (STRS) is one of the most prominent tectonic and geomorphological features in the southern Tibetan Plateau. The Jilong-Oma and Dati basins are located in the northern Himalaya Mountains. The late Cenozoic sedimentary sequences deposited in these two rift basins have archived abundant information about formation and evolution of the STRS and the uplift process of the Tibetan Plateau. The detailed stratigraphic and sedimentologic investigations were conducted on the late Cenozoic sediments in the Jilong-Oma basins. The late Cenozoic sediments in the Jilong-Oma Basin is over 610 m in thickness, including the lower conglomerate member of the fan delta facies (Danzengzhukang Fm., 400-600 m), the middle mudstone interbedded with sandstone member of fluvio-lacustrine facies (Oma Fm., 200-400 m) and the upper conglomerate intercalated with mudstone member of alluvial fan facies (Gongba Fm., 200-0 m). The Hipparion fossils were previously found at the bottom of the Oma Fm. The late Cenozoic sediments in the Dati Basin have a thickness of ~300 m, iucluding the lower mudstone, sandstone and sandy conglomerate member of fluvio-lacustrine faceis (Dati Fm., 80-305 m), and the upper conglomerate member of alluvial fan facies (Gongba Fm., 80-0 m). The Hipparion fossils were previously found at the upper part of the Dati Fm. By comparing with the Zhada Basin in the west part of the Himalaya orogen, it shows that these rift basins experienced the similar sedimentary evolution history and have the comparable Hipparion fossils. Establishing the precise chronology of these sediments and carrying out comprehensive comparison analyses between the rift basins play important roles in understanding the formation and evolution of the STRS, the uplift and deformation processes of the southern Tibetan Plateau and the climate change in the surrounding areas.
Sketch map of 1:50000 geological map of hulugou small watershed in 2012, hulugou watershed is composed of Quaternary loose stratum and pre Cenozoic bedrock stratum. The pores of the bedrock stratum are mainly fissures and covered with thin residual slope deposits. The Pleistocene alluvial proluvial sand gravel layer (q3al + PL) above the piedmont plain is dominant. The loose formation in the front of the glacier is Holocene moraine gravel layer (q4gl), which is distributed under the modern cirque and forms lateral moraine and final moraine dike (ridge).
SUN Ziyong, CHANG Qixin