| 试论戈壁面及指相意义 |
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| 引用本文： | 王贵勇,董光荣.试论戈壁面及指相意义[J].中国沙漠,1995,15(2):124-130. |
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| 作者姓名： | 王贵勇 董光荣 |
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| 作者单位： | 中国科学院兰州沙漠研究所 |
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| 摘 要： | 戈壁是荒漠景观的基本类型之一。从沉积相和沉积环境的角度出发，将戈壁定义为干旱大气与砾石堆积体和裸露基岩表面相互作用的界面，由这个面覆盖的区域称作戈壁。在干旱大气环境下，砾石堆积体或基岩表面经历了机械风化作用、盐分风化和盐分微地貌作用、风力作用及荒漠漆发育等外力作用，使其与其它地区的砾石堆积体或基岩表面出现本质的不同。戈壁面特有的地质、地貌特征指示了干旱气候的存在，其中记录的有效信息可为研究干旱区气候、环境变化及新构造运动提供新的途径。
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| 关 键 词： | 戈壁面，干旱气候，环境 |
AN APPROACHING DISCUSSION ON GOBI PLANE AND ITS FACIES SEGNIFICANCE |
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| Wang Guiyong , Dong Guangrong,Li Sen,Chen Huizhong, Wang Yao.AN APPROACHING DISCUSSION ON GOBI PLANE AND ITS FACIES SEGNIFICANCE[J].Journal of Desert Research,1995,15(2):124-130. |
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| Authors: | Wang Guiyong Dong Guangrong Li Sen Chen Huizhong Wang Yao |
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| Abstract: | Gohbi is one of the primary landscapes in desert . Here, from the angle of sedemental facies or environment in gobi area, the gobi plane has been defined as the interface of the interactionbetween the exposed surface of gravel deposit or bedrock and the arid atmosphere. We refer to theareas overlaid by gobi plane as gobi, where the gobi plane developed over the gravel deposit is gravelgobi , and that over the bedrock is rocky gobi.There are a series of geologieal and geomorphological characters on the exposed surface of graveldeposits and bedrock, which have been built up under the exogenic action in arid atmosphere. Firstly, there are a lot of angular gravels on the surface of gobi plane, which were derived from mechanicalweathering due to the large temperature difference there. Secondly, inasmach as the evaporation is farmore than preciptation, the top-strata of gravel deposits enriched a lot of salt.The clastic grain due tosalt weathering is another main origin of the angular gravel over the gobi plane.While the enrichmentof salt,the physical and chemieal-processes of salt resulted in the formation and development ofpolygons regolith, a peculiar type of microlandform. Thirdly, there are remains of the most commonaction in arid atmosphere,including wind erosion and wind accumulation.Deflation,that the windblows out the finer particle (sand, silt etc.) in the clastic sediments while the gravel remains intopstrata, eventually induces the occurrence of armour of stone on the surface of gobi plane. Theabrasion of blown sand forms ventifacts on the top gravel and the surface of boulder or bedrock. Whenthe wind-drift sand is blocked, there would be aeolian sand deposition. All of the underlying surface ofwind agents is one of the gobi plane, Fourthly, although desert varnish was formed under a variety ofsetting, the most typical varnish is on the surfase of gravel and bedroce of arid gobe areas.The desertvarnish grows slowly under the hyperarid climate, where a little increment of moisture wouldaccelerate the formation of varnish.There are a lot of organic matter in humid climate, which blocksthe development of desert varnish.All the geological and geomorphological characters of gobi plane would be used to determine theposition of the gobi plane in the strata, and to identify how many planes of gobi is in field profile, while the gobi plane as an effective carrier of environmental information could be used to date thegravel sediments or conglomerates, and to reconstruct the palaeoclimatic change, channel swing andneotectonics.Therefore,the establishment of the new concept of gobi plane provides a new approachto study the environmental and climatic change in arid land, which would significantly prompt theresearch work in gobi area. |
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| Keywords: | Gobi plane Arid climate Environment |
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