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Geological Anomaly of China 被引量:3
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作者 Zhao Pengda(Faculty of Earth Resources,China University of Geosciences, Wuhan 430074)Wang Jinggui Rao Minghui Li Haochang(Department of Geology, East China College of Geology, Fuzhou 344000) 《Journal of Earth Science》 SCIE CAS CSCD 1995年第1期97-106,共10页
Geological anomaly is a geological body or geological body combination different from its surroundings in composition, structure, or genetic sequence. If there is a value (value interval ) that works as a valve repres... Geological anomaly is a geological body or geological body combination different from its surroundings in composition, structure, or genetic sequence. If there is a value (value interval ) that works as a valve representing the background field, exceeding or lower than the valve value,it is called a geological anomaly. Geological anomalies can be divided into high geological anomaly and low geological anomaly .The former shows the area that is more complex in composition, Structure or genetic sequence than its surroundings; while the latter just gives an opposite indication, i. e. much simpler. According to their distribution and delimitation markers, geological anomalies can be classified into (1)global geological anomaly; (2)regional geological anomaly; (3) local geological anomaly; (4) minor geological anomaly and (5)micro-geological anomaly .The methods for delimiting geological anomalies include (1)crustal elevation-subsidence coefficieat (G value ) determination; (2) geological complex coefficient (C value ) determination; (3) entropy (H value ) determination; (4) geological similarity coefficient (S value ) determination and (5 ) geological correlation coefficient (R value ) determination. As the result of the movements of Eurasian, Pacific and Indian Plates, the Chinese geological anomalies, including 11 regional ones and 32 main local ones, most Paleozoic in age, are distributed in strip on the margin or the outer and inner folded zones in the east and west arcs of the block symmetric arc tectonic system (BSATS), which controls the distribution of various minerals in China. Thus, geological anomaly theory is of great significance in searching for large, super-large and very large ore deposits. 展开更多
关键词 geological anomaly delimitation of geological anomaly distribution of geological anomaly block symmetic arc tectonic system genetic analysis metallogenic analysis.
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Analysis of the negative effects of groundwater exploitation on geological environment in Asia 被引量:1
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作者 ZHANG Jian-kang WEN Xue-ru +2 位作者 GAO Yun YUE Chen YI Qing 《Journal of Groundwater Science and Engineering》 2015年第2期202-212,共11页
This paper summarizes the negative effects on geological environment caused by groundwater exploitation and its distribution. There are seven main types of the geological environment negative effects, which are genera... This paper summarizes the negative effects on geological environment caused by groundwater exploitation and its distribution. There are seven main types of the geological environment negative effects, which are generally as follows:(1) Constant decrease of groundwater level is mainly distributed in China(East Asia), India(South Asia), Tajikistan(Central Asia) and Saudi Arabia(West Asia);(2) land subsidence occurs mainly in eastern plains of East Asia and west Siberian Plain of North Asia;(3) seawater intrusion occurs mainly in China, Japan and South Korea in East Asia, Philippines and Indonesia in Southeast Asia, the Indian coastal areas in South Asia;(4) groundwater level decline caused by groundwater exploitation in oil fields;(5) mining collapse is mainly in 50° to 70° north latitude band;(6) the total area of karst collapse in China of East Asia is as much as 197.05 km^2; and(7) ground fracture is mainly distributed in the North China Plain, Fenwei Plain and the Yangtze River Delta. Asia can be divided into 6 zones in terms of the geological environment negative effect caused by groundwater exploitation. According to analysis, with the increasing intensity of human activities, geological environment issues become more and more serious, therefore it is vital to control the human activities within the scope of 5× 10~5 people/km^2 to 9.9× 10~5 people/km^2 for the effective control of the size of the affected area by geological environment problems. 展开更多
关键词 ASIA Groundwater development geological environment negative effect and distributed regions Severity of geological environment problems
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The Origin of Spirula spirula (Linne, 1758)
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作者 E. O. Heyfetz 《Journal of Life Sciences》 2018年第1期30-46,共17页
The article presents evidence regarding the origin of Spirula from spiral-shelled forms. The geological age of the species is revised from the Miocene to the Jurassic. The causes of the reorientation of the shell are ... The article presents evidence regarding the origin of Spirula from spiral-shelled forms. The geological age of the species is revised from the Miocene to the Jurassic. The causes of the reorientation of the shell are elucidated. The mode of life of the mollusk is specified. The influence of the theory on facts perception is shown. 展开更多
关键词 BUOYANCY CHAMBERS distribution and geological age GUARD keels mode of life ORIGIN orientation of the shell phragmacone proostracum Spirula L.
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