【摘要】 基于SRTM3-DEM数据,运用ArcGIS技术,采用空间分析、三维地表形态分析和剖面形态分析方法,结合野外调查,对克拉玛依盆地以西、塔城盆地以东的西准噶尔山地的地貌结构进行了初步研究,划分出4级夷平面,讨论了各级夷平面的特征,依据地表特征分析对研究区内的构造地貌区进行了划分。4级夷平面海拔高度分别是2 734~1 760m、1 520~1 200m、1 000~300m和800~660m。参考地表面三维统计得到的拐点(1 320m/1 270m),将1 270m以上地貌面分为2级夷平面:1 760m以上夷平面(Ⅰ)和1 520~1 200m夷平面(Ⅱ),地形起伏度均在500~200m以内。Ⅱ级夷平面可能发育于白垩纪至新近纪,山地剥蚀的后期与新近系昌吉河群相对比。1 000m以下分为两级剥蚀面,其中之一,剥蚀面高度1 000~660m,并一直延伸至300m高度,为一变形的山麓及山前剥夷面(Ⅲ)。该剥蚀面具有埋藏剥蚀面性质,形成于中更新世—晚更新世。另一级山间剥蚀面出现在860~660m高度上(Ⅳ),发育于晚更新世后期至全新世。4级夷平面代表了山地的4次稳定时期与其间的4次快速抬升,第Ⅲ级剥蚀面的变形记录了青藏高原晚第四纪隆升的远程效应。不同分区之间的构造地貌差异为区域构造分析提供了有价值的分区信息,构成区域构造分区中的一个重要因素。区域研究表明,西准噶尔山地的总体构造线方向呈NE向展布,其与东部的准噶尔盆地和西部塔城盆地及以西地区的NW向构造线方向明显不同,受控于数条NE向断裂的南部扎伊尔山地与北部吾尔喀什尔山地的盆-山间列的构造地貌组合构成了区域南、北之间的对比。依据DEM所做的地表特征分析,把研究区分为北部中山与盆地间列区(Ⅰ-1)、南部中低山区(Ⅰ-2)和东南部山缘及山前平原区(Ⅱ)3个构造地貌区。西准噶尔山地(Ⅰ区)属于天山—准噶尔—萨彦—贝加尔构造强变形带和地震活动带的一部分,这里虽未发生过强烈地震,但具备了发震的基本条件,且临近克拉玛依油气资源开发重地,建议进行必要的地震观测和地震预报。更多还原

【Abstract】 By using spatial analysis,three dimensional surface analysis,profile shape analysis and the platform of Arc GIS based on SRTM3-DEM data,and combining with field geological survey,the geomorphologic structures of West Junggar Mountain between the western part of Karamay Basin and the eastern part of Tacheng Basin are studied;the planation surfaces are divided into four levels,and their structural geomorphologic features are discussed;and three subareas of structural geomorphology are divided.There are at least four levels of planation surfaces in the mountain,which appear on 2734-1760m,1520-1200m,1000-300mand 800-660mabove the sea level.Two planation surfaces,at over 1 760mabove the sea level(the levelⅠ)and at between 1520mand 1200mabove the sea level(the levelⅡ)respectively,were detected based on the inflection point obtained in three dimensional statistics for the ground surface(at 1320m/1270m above the sea level),and both undulations of them are of no more than 500-200m.The levelⅡ was shaped in the Cretaceous-Neogene Period,and the later period of denudation coincided with Changjihe Group shaped in the Neogene Period.There are two denudation planes under the inflection point.One of them exits in1000-660mand extends to 300mabove the sea level,and it is a deformed denudation plane existing at the foothill and the front of mountain(the levelⅢ),and it was shaped during the Middle Pleistocene to the Late Pleistocene and buried by the pluvial-alluvial deposits of the Late Pleistocene-Holocene Epoch.The other appears in 860-660mabove the sea level(the levelⅣ),it was shaped during the Late Pleistocene-Holocene Epoch as the pluvial-alluvial deposits of the Late Pleistocene Epoch have been whittled down.The above four level planations represent four stable periods and four rapid uplift periods among planations,but the deformation of levelⅢrecorded a response of the uplift of Qinghai-Tibet Plateau during the Late Quaternary Period.The structural geomorphologic difference in space provides some valuable information for the partition of regional tectonics,which composes one important factor for regional tectonic partition.The research of West Junggar Mountain shows that the direction of structural line lies as a whole on the direction of northeastsouthwest,which is different from the direction of northwest-southeast of Junggar Basin and Tacheng Basin and western part of it,and this makes a contrast between Zaire Mountain of the southern part controlled by several faults in the direction of northeast and the structural geomorphologic constitution of alternatingly distributed basins and mountains in Ur Kashi Mountain of the north part.Three structural geomorphologic subareas were divided according to the DEM ground surface features;they are northern subarea of the alternatingly distributed middle mountains and basins(Ⅰ-1),south subarea of middle-low mountains(Ⅰ-2),and south-eastern subarea of the mountain edges and the frontier plane of the mountain(Ⅱ).The West Junggar Mountain(Ⅰarea)belongs to a part of intense deformation zone of structure and seismic active zone of Tianshan-Junggar-Sayan-Baikal,although there has not been a violent earthquake in history,it possesses some basic conditions of seismic action in future,and it is close to the petro-gas development area in Karamay Basin, so essential seismic observation and seismic forecast is suggested.更多还原