Min L.-R.,Chinese Academy of Geological Sciences |
Wang Y.,Chinese Academy of Geological Sciences |
Wang C.,Ningxia Institute of Geological Survey |
Xu K.-M.,Shandong Institute of Geological Survey |
And 3 more authors.
Geology in China | Year: 2016
Quaternary geology and geomorphology map is one of the series of maps in the second edition of the National Regional Geology Annals, with special attention paid to the close integration with ecological environment and geological disasters. The map includes such important geological contents as Quaternary geological epoch, genetic type, combination type of lithology and geomorphology genesis, active faults and transgression range with the attachment of the typical profiles of Quaternary geology-geomorphology and important landscape attractions. The map has the following characteristics: (1) Digital elevation model (DEM) grayscale image is for the first time used as background for the geographic base map. (2) Quaternary geology features and geomorphologic genetic types are compiled on the same map. (3) The colors of Quaternary geological bodies are indicated by the colors of genetic types. (4) Geomorphologic part is divided into different levels of morphological types and geneses of distinctive micro-topography attractions. In short, the map is a brand new one with three-dimensional drawing, obvious terrain elevation, fine arrangement, bright color, and availability for disaster prevention and control and geological tourism applications.
Huang X.,China Earthquake Administration |
Zhang J.,China Earthquake Administration |
Peng P.,CAS Institute of Geology and Geophysics |
Li T.,Ningxia Institute of Geological Survey
Acta Petrologica Sinica | Year: 2013
Ductile deformation shear zones in varied degrees are preserved in the crystalline basement in the northern segment of Helan Mountain. Four stages of ductile shearing are identified by detailed outcrop research and microstructure study from the Paleoproterozoic crystalline basement in the northern segment of Helan Mountain. The earliest one is a kind of layer-paralleled shear zone composed by banded khondalite and granitic gneisses along with lots of parallelling folds, boudinages and sheathe folds, showing north to south extension with deforming characteristics of mid-lower crust level. The second one is mylonitic gneiss shear zone in high amphibolite to granulite facies resulted from a compressional tectonic movement in N-S direction to cause fast uplift of the high temperature and high pressured metamorphosed khondalite from lower crust to middle crust. The third kind of shear zone metamorphosed in low amphibolite to high greenshist facies maybe happened in the late extensional collapse stage in the same orogenic cycle with the khondalite, lifting the crystalline basement more up into the middle crust. They are composed of two sets of molynitic shear zones caused by a NW-SE extension followed another NE-SW extension. The latest kind of ductile shear zones are NE to EW trending greenshist-faced mylonitic shear zones in left-lateral thrusting sense, bring the crystalline basement up into the upper crust through the brittle-ductile transition zone. They could be resulted in another orogeny different from the khondalite because owning an obviously different kinematic character from the extensional shear zones. Similar structural deformation characters and ductile shear zones occurred in the Wula Mountains and Daqing Mountains as the northern segment of Helan Mountain indicate the existence of a EW-trending Paleoproterozoic collision orogenic belt in west part of the north edge of the North China Craton and perhaps followed by another orogeny in late-Paleoproterozoic.
Zheng H.,Jilin University |
Sun X.M.,Jilin University |
Zhu D.F.,Petrochina |
Tian J.X.,Ningxia Institute of Geological Survey |
And 3 more authors.
Science China Earth Sciences | Year: 2015
The Erguna Fault runs along the east bank of the Erguna River in NE China and is a large-scale ductile shear zone comprising granitic mylonites. This paper reports on the geometry, kinematic indicators, and 40Ar/39Ar biotite ages of the granitic mylonites,to constrain the structural characteristics, forming age, and tectonic attribute of the Erguna ductile shear zone. The zone strikes NE and records a top-to-the-NW sense of shear. A mylonitic foliation and stretching lineation are well developed in the mylonites, which are classified as S-L tectonites. Logarithmic flinn parameters (1.18–2.35) indicate elongate strain which approximatesto plane strain. Kinematic vorticity numbers are 0.42–0.92 and 0.48–0.94, based on the polar Mohr diagram and the oblique foliation in quartz ribbons, respectively, suggesting that the ductile shear zone formed under general shear, or a combinationof simple and pure shear. According to finite strain and kinematic vorticity analyses, the Erguna Fault is a lengthening-thinning ductile shear zone that formed by extension. The deformation behavior of minerals in the mylonites indicates that the fault was the site of three stages of deformation: an initial stage of middle- to deep-level, high-temperature shear, a post-stress recovery phase of high-temperature static recrystallization, and a final phase of low-temperature uplift and cooling. The 40Ar/39Ar plateau ages of biotite from the granitic mylonites are 106.16 ± 0.79 and 111.55 ± 0.67 Ma, which constrain the timing of low-temperature uplift and cooling but are younger than the ages of metamorphic core complexes (MCCs) in the Transbaikalia-northeast Mongolia region. Using measured geological sections, microtectonics, estimates of finite strain and kinematic vorticity, and regional correlations and geochronology, we conclude that the Erguna Fault is an Early Cretaceous, NNE-trending, large-scale, sub-horizontal, and extensional ductile shear zone. It shares a similar tectonic background with the MCCs, volcanic fault basins, and large and super-large volcanic-hydrothermal deposits in Transbaikalia-northeast Mongolia and the western Great Khingan Mountains, all of which are the result of overthickened crust that gravitationally collapsed and extended in the Early Cretaceous after plate collision along the present-day Sino-Russia-Mongolia border tract. © 2015, Science China Press and Springer-Verlag Berlin Heidelberg.
Jiang X.-W.,China University of Geosciences |
Jiang X.-W.,Water Resources University |
Wan L.,China University of Geosciences |
Wan L.,Water Resources University |
And 5 more authors.
Geophysical Research Letters | Year: 2014
Groundwater flow systems and stagnant zones in drainage basins are critical to a series of geologic processes. Unfortunately, the difficulty of mapping flow system boundaries and no field example of detected stagnant zones restrict the application of the concept of nested flow systems. By assuming the variation in bulk resistivity of an aquifer with uniform porosity is mainly caused by groundwater salinity, the magnetotelluric technique is used to obtain the apparent resistivity of a profile across a groundwater-fed river in the Ordos Plateau, China. Based on the variations in apparent resistivity of the Cretaceous sandstone aquifer, the basin-bottom hydraulic trap below the river has been detected for the first time, and its size is found to be large enough for possible deposition of large ore bodies. The boundaries between local and regional flows have also been identified, which would be useful for groundwater exploration and calibration of large-scale groundwater models. Key Points The hydraulic trap with higher TDS has been identified for the first time The continuous boundaries of local and regional flow systems have been mapped The magnetotelluric method is useful for large-scale flow system studies ©2014. American Geophysical Union. All Rights Reserved.
Li H.,Ningxia Institute of Geological Survey |
Ma X.,Ningxia Institute of Geological Survey |
Li M.,Ningxia Institute of Geological Survey |
Liang Z.,Ningxia Institute of Geological Survey |
Huang S.,Ningxia Institute of Geological Survey
Acta Seismologica Sinica | Year: 2014
Xiangshan northern margin active fault zone, mainly characterized by sinistral strike-slip faults with a little dip-slip component in the Holocene, is one of the important active faults of arc structural belt in the northeast margin of Tibetan Plateau. The fault zone consists of nine discontinuous secondary faults and is divided into eastern and western segment by the Yiwanquan discontinuity. Based on the field survey, the study on active intensity of the eastern segment of the fault zone since the Late Pleistocene has been conducted in different periods. The results show that the active intensity of the east segment since the Late Pleistocene is not strong because the average horizontal displacement rates are 1.44, 0.53 and 1.01 mm/a in early-middle stage of Late Pleistocene, late stage of Late Pleistocene, and Holocene, respectively. The sinistral strike-slips of the faults distribute inhomogeneously along the strike, and the location of the maximal slip (the center of the activation) displaced eastward, resulting in the Jiangou-Liugangjing secondary fault being the most active part up to now.
Huang X.-N.,China Earthquake Administration |
Zhang J.-S.,Ningxia Institute of Geological Survey |
Li T.-B.,Ningxia Institute of Geological Survey |
Liu F.,China Earthquake Administration |
Feng J.,National Earthquake Response Support Service
Dizhen Dizhi | Year: 2012
The recent researches of active faults related to the north segment of the eastern boundary of GTSR(the great triangular seismotectonic region of Central Asia), including the north part of the North-South Seismic Belt and central Mongolia, are summarized based on their geological background and seismic activities at present. The north segment of the eastern boundary of the GTSR is composed by a series of terminal structures, lateral structures of large sinistral strike-slip faults, and transtensional graben fault systems between the large sinistral strike-slip faults. From south to north, the fault systems, which compose the north segment of the eastern boundary of GTSR, include: (1)Liupanshan arcuate fault zone, which is the eastern terminal compression structure of the Haiyuan Fault zone and Zhongwei-Tongxin Fault zone; (2)Zhuozishan-Helanshan Fault system, which is a transtensional graben fault systems between the Zhongwei-Tongxin Fault zone and the Yabulaishan-Bayanxiboshan Fault zone; (3)Langshan-Sertengshan piedmont fault system, which is the eastern relaxing structure of the Yabulaishan-Bayanxiboshan Fault zone; (4)Dalandzadgad Fault system, which is the eastern terminal compression structures of the Gobi-Tienshan Fault zone and Gobi-Altay Fault zone; (5)Mogod Faults system, the possible eastern terminal compressional structures of the North Hangay Fault zone; and (6)Hovsgol rift system, which is the extensional lateral structures of the Tunka Fault zone. The nature of the seismic structures of the north segment of the eastern boundary of the GTSR is the re-activation of the pre-existing faults that locate beside or on the terminations of giant strike-slip fault zones in the present regional stress field, controlled by the northward pushing of the Indian-Eurasia collision and local upper mantle material flow or significant anisotropies deep in the upper mantle.
Xu G.-P.,Ningxia Institute of Geological Survey |
Zhang X.-D.,Ningxia Institute of Geological Survey |
Ai N.,Ningxia Institute of Geological Survey |
Meng F.,Ningxia Institute of Geological Survey |
And 4 more authors.
Northwestern Geology | Year: 2011
Weining North Mountain area lies in the east of Hexi Corridor Fe-Mo-Fluorite-Salt-Attapulgitepetroleum metallogenic belt, where is one of the most important perspective regions of the mineralization of metallic minerals in Ningxia, having many significant metallic minerals such as gold, sliver, and copper. For a long time, the understanding about iron ore mineralization in the area are much different. We discuss the regional mineralization law of iron ore in the area from the way of typical deposit and the regional deposit, obtaining a primary conclusion about the regional mineralizing law of iron ore including genetic type. We also believe that the iron ore mineralization of Weining north mountain area mainly occurred in Carboniferous-Permian, which is characterized by the sedimentary mineralization in the early stage and by the tectonic-hydrothermal activities in the late; the stratum and lithofacies and lithology are the main control factors of iron ore mineralization and the geologic structure's function is minor because major mineralization is deposition, though it plays a certain positive role in mineralization; the exploration direction of iron deposits in the area should focus on the deposition's siderite first, and then hematitelimonite which is formed by superimposition transformation of deposition siderite seam and tectonic (faults).
He X.,Wuhan University |
Lu Z.,Wuhan University |
Weng P.,Ningxia Institute of Geological Survey |
Li H.,Ningxia Institute of Geological Survey |
And 2 more authors.
Diqiu Kexue - Zhongguo Dizhi Daxue Xuebao/Earth Science - Journal of China University of Geosciences | Year: 2014
Fossil caddisfly (Insecta: Trichoptera) larval cases have been recently discovered in the Early Cretaceous lacustine deposits (Madongshan Formation and Naijiahe Formation) in Liupanshan basin, Ningxia. The arrays of caddisfly larval cases occur as superimposed layers of vertically oriented cases. The fossils are gregarious, dense, parallel to each other and closely packed. The single larval case is conical and similar in size (generally 13 mm in length and averagely 2.5 mm in diameter). The wall of the caddisfly larval cases is divided into three layers, including internal, external dark organic matter layers which have micrite structures and are composed of lime muds, and the middle layer of cemented aphanitic particles composed of organic pellets. The calcified organic pellets are orbicular, spheroidicity and ovate, with its size ranging from 0.10 to 0.15 mm wide by averagely 0.3 mm long. The pellets are in regular arrangement, and their long axes are mostly perpendicular to the growth direction of the caddisworm cases. The larval cases in Liupanshan basin are attributed to Coprindusia in ichnology according to the pellets along the walls of the cases. By comparing the features of various tube-maker organism in morphology and bionomy, and the habitat, size and shape of cases, the composition of case-building particles, and case construction way, combining the analysis to insect body fossil from the same layers in which the caddisfly cases preserved, it seems like that the caddisfly larval cases in Liupanshan basin are Ningxiapsyche fangi from Ningxiapsychidae.
Mi C.,Tianjin University |
Ma A.,Linyi Bureau of Land and Resources |
Zhang X.,NingXia Institute of Geological Survey |
Jiang L.,Linyi Bureau of Land and Resources
WIT Transactions on Information and Communication Technologies | Year: 2014
PCA is the method based on the relativity of variables, which express multivariable using several factors without losing information as far as possible. In the multispectral images or hyper-spectrum images, there is much redundant information because of relativity of the data in different band. Employing PCA most information of the RS images can be expressed with fewer bands, it not only reduces data size but also eliminates redundant information. PCA method is always used to data preprocessing in order to depress data and enhance image. Article on the PCA in remote sensing image processing examples demonstrate the practical application of applied research. © 2014 WIT Press.