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Journal of Coal Science & Engineering(China) 2011年第2期17卷 157-162页

作者： ZHU Hong-qing LIU Xing-kui ZHANG Ru-ming ZHANG Sheng-zhu Faculty of Resource and Safety Engineering China University of Mining ＆ Technology （Beijing） Beijing 100083 China State Key Lab of Coal Resources and Safe Mining China University of Mining ＆ Technology （Beijing） Beijing 100083 China

The influence of gas drainage on float coal spontaneous combustion in the work face with ＂U＂ style ventilation was studied. Numerical simulation was used to compare the mutative law of steady flow and density field in the gob area under different drainage conditions by solving the equation set, including mass, momentum, and component transition. Consequently, the sequence of drainage effect and safety was obtained. The result manifests that the more effective the drainage pattern is, the easier float coal spontaneous combustion is caused due to air being guided into the depth of the gob area when the drainage position is arranged in the gas accumulation area. If the widened scope of oxidation zone exceeds the upper limit of the work face advancing speed, nitrogen injection should be applied to decrease the probability of spontaneous combustion. Then, the pipe laying drainage in the upper angle is most economical and safe compared with other drainage patterns when only the situation of gas accumulation is controlled in the upper angle. Finally, drainage pressure must not be too great. Otherwise the drainage density will decrease even if hazard is caused by back flow possibly happening in the return outlet when the drainage position is arranged near the work face.

关键词： gas drainage float coal spontaneous combustion numerical simulation drainage pattern drainage effect and safety

Tectonic control on the drainage system in a piedmont region in tectonically active eastern Himalayas

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Frontiers of Earth Science 2012年第1期6卷 29-38页

作者： Chandreyee GOSWAMI Dhruba MUKHOPADHYAY Bikash Chandra PODDAR Asutosh College Saltlake CityKolkata 700026India Raman Center for Applied and Interdisciplinary Sciences Saltlake CityKolkata 700075India BE 267 Saltlake CityKolkata 700064India

The impact ofneotectonic activity on drainage system has been studied in a large alluvial fan in the eastern Himalayan piedmont area between the Mal River and the Murti River. Two distinct E-W lineaments passing through this area had been identified by Nakata （1972, 1989） as active faults. The northern lineament manifested as Matiali scarp and the southern one manifested as Chalsa scarp represent the ramp anticlines over two blind faults, probably the Main Boundary Thrust （MBT） and the Himalayan Frontal Thrust （HFT）, respectively. The fan surface is folded into two antiforms with a synform in between. These folds are interpreted as fault propagation folds over the two north dipping blind thrusts. Two lineaments trending NNE-SSW and nearly N-S, respec- tively, are identified, and parts of present day courses of the Murti and Neora Rivers follow them. These lineaments are named as Murti and Neora lineaments and are interpreted to represent a conjugate set of normal faults. The rivers have changed their courses by the influence of these normal faults along the Murti and Neora lineaments and their profiles show knick points where they cross E-W thrusts. The overall drainage pattern is changed from radial pattern in north of the Matiali scarp to a subparallel one in south due to these conjugate normal faults. The interfluve area between these two rivers is uplifted as a result of vertical movements on the above mentioned faults. Four major terraces and some minor terraces are present along the major river valleys and these are formed due to episodic upliftment of the ground and subsequent down- cutting of the rivers. The uppermost terrace shows a northerly slope north of the Chalsa scarp as a result of folding mentioned above. But rivers on this terrace form incised channels keeping their flow southerly suggestingthat they are antecedent to the folding and their downcutting kept pace with the tectonism.

关键词： alluvial fan drainage pattern thrust normalfault active tectonic

Human settlement and changes in the distribution of river systems in the Minqin Basin over the past 2000 years in Northwest China

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Ecosystem Health and Sustainability 2017年第11期3卷 2-13页

作者： Yaowen Xie Qiang Bie Chansheng He School of Earth and Environmental Science Lanzhou UniversityLanzhouChina The Key Laboratory of Western China’s Environmental Systems Ministry of Education(MOE)LanzhouChina Center for Dryland Water Resources Research and Watershed Science Lanzhou UniversityLanzhouChina

Introduction:Arid area is an important base for human settlement,however,long and drastic human activities have altered the drainage patterns in the arid watersheds significantly,causing serious ecological *** study,through a case study of the Minqin Basin,a microcosm of the artificial oases in the arid northwest China,used the multitypes of data to recover the spatial distribution of human settlement and drainage patterns during historical period and analyze the relationship between them over the past 2000 ***:Before the Han Dynasty(121 BC),the utilization of water resources in the Minqin Basin was in the primitive stage and the drainage pattern maintained the natural *** the Han(121 BC-220)to the Wei-Jin Dynasties(220-316),the utilization of water resources intensified unprecedentedly,but the natural shape of the river systems was still *** the following 1,000 years or so,the drainage pattern was in the state of“following its own course”due to the small human *** the Ming Dynasty(1368-1644),with the alteration of the main rivers,the water resource utilization increased obviously,but the human reclamations were mainly confined to the southern part of the *** the Qing Dynasty(1644-1911),the reclamation of the Liulin Lake area significantly changed the drainage patterns,resulted in the drastically northward expansion of human *** the foundation of the People’s Republic of China(PRC)in 1949,the artificial water system completely replaced the natural water system and intensified the ecological problems in the ***:The changes over the past 2000 years show the drastic impacts of human activities on the alterations of the drainage patterns and related ecological problems in the arid Northwest ***:Rehabilitation of such ecological impairments requires both ecological restoration projects and changes in human paradigm and behavior over multiple temporal and spatial scales.

关键词： Minqin Basin Chinese Dynasties human settlement utilization of water resources drainage pattern

Three-dimensional Evolutionary Models of the Qiongxi Structures,Southwestern Sichuan Basin,China:Evidence from Seismic Interpretation and Geomorphology

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Acta Geologica Sinica(English Edition) 2009年第2期83卷 372-385页

作者： JIA Qiupeng JIA Dong LUO Liang CHEN Zhuxin LI Yiquan DENG Fei SUN Shengsi LI Haibin Department of Earth Sciences Nanjing University Nanjing Jiangsu 210093 China Research Institute of Petroleum Exploration and Development PetroChina Company Limited Beijing 100083 China China Development Bank Beijing 100037 China

Fold terminations are key features in the study of compressional fault-related folds. Such terminations could be due to loss of displacement on the thrust fault or/and forming a lateral or oblique ramp. Thus, high-quality seismic data would help unambiguously define which mechanism should be responsible for the termination of a given fault-related fold. The Qiongxi and Qiongxinan structures in the Sichuan Basin, China are examples of natural fault-propagation folds that possess a northern termination and a structural saddle between them. The folds/fault geometry and along-strike displacement variations are constrained by the industry 3-D seismic volume. We interpret that the plunge of the fold near the northern termination and the structural saddle are due to the loss of displacement along strike. The fault geometry associated with the northern termination changes from a flat-ramp at the crest of the Qiongxinan structure, where displacement is the greatest, to simply a ramp near the northern tip of the Qiongxi structure, without forming a lateral or oblique ramp. In this study, we also use the drainage pattern, embryonic structure preserved in the crest of the Qiongxinan structure and the assumption that displacement along a fault is proportional to the duration of thrusting to propose a model for the lateral propagation of the Qiongxinan and Qiongxi structures. Specifically, we suggest that the structure first initiated as an isolated fault ramp within brittle units. With increased shortening, the fault grows to link with lower detachments in weaker shale units to create a hybridized fault-propagation fold. Our model suggests a possible explanation for the lateral propagation history of the Qiongxinan and Qiongxi structures, and also provides an alternative approach to confirming the activity of the previous Pingluoba structure in the southwestern Sichuan Basin in the late Cenozoic.

关键词： fault-propagation fold fold termination embryonic structure drainage pattern Sichuan

Analysis of Morphometric Parameters and Radioactive Characteristics Using Remote Sensing Data and GIS Techniques in the Wadi Wizr Basin Area, Central Eastern Desert, Egypt

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Journal of Geoscience and Environment Protection 2023年第6期11卷 197-219页

作者： Sameh Anwar Ibrahim Hammouda Soliman Abu Elatta A. Mahmoud Nuclear Materials Authority Cairo Egypt

The purpose of this study is to demonstrate how modern technologies such as geographic information systems (GIS) and digital elevation models can help in the creation of a geographic database for the Wadi Wizr basin in Egypt’s Central Eastern Desert, in addition to examining and analysing the radioactive properties of various rocks. This was accomplished with the help of a digital elevation model (DEM) with a 30 metre accuracy and GIS software in 10.8 Arc Map. The RS-230 was also used to measure uranium and thorium concentrations. GIS softwares and digital elevation models have been shown to be more effective than the traditional method. This was demonstrated by the flexible and quick working method, the accuracy of the parameters used, and the results of the morphometric analysis of the basin river network. In addition to, the main drainage pattern from subtype to tree type, where the branching ratio was (1.59). This basin could also cause flooding. Similar studies, according to the results of this study, should make greater use of geographic information system technology and modern data sources. Wadi Wizr also has a radioactive anomaly, with uranium equivalent concentrations reaching 70 ppm in some fault parts.

关键词： Wadi Wizr Basin Morphometric Analysis drainage pattern Radioactive Characteristics Remote Sensing Geographic Information System