Tectonic Landform of Quaternary Lakes and Its Implications for Deformation in the Northern Qinghai-Tibet Plateau

The Hohxil region in the northern Qinghai-Tibet Plateau is occupied by numerous plateau lakes, which have long been inferred as being tectonic products. However, so far little evidence has been found to support this tentative inference. Field survey and morphotectonic analysis of TM satellite images in the eastern segment of the Hohxil region revealed that Kusai Lake and Yelusu Lake are S- shaped pull-apart basins, which were dominated by left strike-slip master faults trending WNW-ESE. The pull-apart distances of the two lakes are analyzed to be 〈15-20 km and 15 km respectively. Based on studies of the faulting rate, the initiation ages of the pull-apart basins are suggested to be approximately in the Early Pleistocene. The pull-apart basin tectonics is further regarded as a common mechanism for the widely distributed large lake basins in the northern Qinghai-Tibet Plateau. Regional distribution of these pull-apart basins and their substantial intra-block slip suggest that a sinistral shear stress, which is independent of the distinguished strike-slip faults, has been imposed on across the northern Qinghai-Tibet Plateau. Thus, the intra-block slip may be an important expression of the eastward extrusion of the Plateau crustal material in accommodating the ongoing continent-continent convergence between India and Eurasia. The revelation of pull-apart tectonics within the Plateau hinterland provides field evidence and a possible style of deformation for the newly proposed continuous deformation by the global positioning system （GPS） measurement across the northern Qinghai-Tibet Plateau. A model, with respect to systematic tectonic landform development, for pull- apart basins is finally proposed.

微生物基因检测技术在鄂尔多斯盆地神府南气田勘探中的应用

针对鄂尔多斯盆地构造复杂,储层分布差异大,气藏富集规律不明等问题,本文采用微生物基因检测技术的荧光定量PCR法测量研究区样品中油气指示基因的丰度,同时利用高通量基因测序法检测样品中的烃类微生物种群类型,分析认为,本区主要有东北部、西部、南部三个烃类异常带,展布特征与沉积认识吻合,且西部、南部有亲缘关系,东北部与二者无亲缘关系,可能与致密气、煤层气不同层系烃的逸散有关。实钻表明,本技术对于鄂尔多斯盆地致密气和煤层气混源区的含油气性评价方面具有较好的适用性,为油气有利区带筛选提供参考依据。

青藏高原东北缘清水河流域地貌特征及其构造意义

新生代以来,受印度板块与欧亚板块剧烈碰撞汇聚的影响,青藏高原快速隆起,其构造变形不断向北东扩展、挤出,造就了清水河流域及其周缘独特的构造地貌格局。通过对清水河流域构造地貌的研究,可以揭示新生代晚期以来青藏高原东北缘变形机制和地貌演化过程。本文基于30 m分辨率DEM数据,利用ArcGIS 10.2软件对清水河流域地貌参数进行提取,精确计算了22条子流域的河长坡降指标(SL)及Hack剖面、面积-高程积分(HI)、流域不对称度(AF)以及盆地延伸率(Re)这4种地貌形态指数,定量获取了清水河流域的地貌形态特征,再结合4个参数求得各子流域的相对活动构造指数(Iat),对研究区的相对构造活动性程度进行分析。得到以下结论:(1)研究区SL值分布在70.1~353.9之间,表明整个流域内构造活动性存在区域差异且整体活动变形程度较高;(2)受海原断裂带和香山-天景山断裂带的影响,研究区西岸流域HI和AF指数的平均值大于东岸,Re指数的平均值小于东岸,表明西岸构造活动性大于东岸;(3)研究区相对活动构造指数(Iat)处于第一、二级的面积达到80%,主要分布在西岸,表明整个流域的构造活动性强烈,且展现由东向西活动性逐渐增强的趋势。同时结合相关地质资料综合评估流域构造活动状态,并据此对河流发育阶段以及构造运动进行分析。

Quantifying spatial scale of positive and negative terrains pattern at watershed-scale:Case in soil and water conservation region on Loess Plateau

The positive and negative terrains(P-N terrains) widely distributed across China's Loess Plateau constitute the dual structure characteristic of loess landforms. Analysis of loess P-N terrains at the watershed scale can serve to elucidate the structural characteristics and spatial patterns of P-N terrains, which benefits a better understanding of watershed evolution and suitable scales for loess landform research. The Two-Term Local Quadrat Variance Analysis(TTLQV) is calculated as the average of the square of the difference between the block totals of all possible adjacent pairs of block size, which can be used to detect both the scale and the intensity of landscape patches(e.g., plant/animal communities and gully networks). In this study, we determined the latitudinal and longitudinal spatial scale of P-N terrain patterns within 104 uniformly distributed watersheds in our target soil and water conservation region. The results showed that TTLQV is very effective for examining the scale of P-N terrain patterns. There were apparently three types of P-N terrain pattern in latitudinal direction(i.e., Loess Tableland type, Loess Hill type, and Transitional Form between Sand and Loess type), whereas there were both lower and higher values for P-N terrain pattern scales in all loess landforms in the longitudinal direction. The P-N terrain pattern alsoclearly presented anisotropy, suggesting that gully networks in the main direction were well-developed while others were relatively undeveloped. In addition, the relationships between the first scales and controlling factors(i.e., gully density, nibble degree, watershed area, mean watershed slope, NDVI, precipitation, loess thickness, and loess landforms) revealed that the first scales are primarily controlled by watershed area and loess landforms. This may indicate that the current spatial pattern of P-N terrains is characterized by internal force. In selecting suitable study areas in China' Loess Plateau, it is crucial to understand four control variables: the spatial scale of the P-N terrain pattern, the watershed area, the main direction of the watershed, and the loess landforms.

Geomorphic features of Quaternary glaciation in the Taniantaweng Mountain, on the southeastern Qinghai-Tibet Plateau

We present geomorphological evidence for multiple glacial fluctuations during the Quaternary in the Taniantaweng Mountain, which is situated at the transition zone of the southeastern Qinghai-Tibet Plateau and the Yunnan-Guizhou Plateau. To reconstruct the history of glacial evolution during the Quaternary Glaciation, we present a ~13000 km^2 geomorphologic map(1:440,000) for the Quaternary glaciations, as well as three electron spin resonance(ESR) ages and three optically stimulated luminescence(OSL) ages from the landforms. By integrating these with ages from previous studies, four major glacial advances are identified during marine oxygen isotope stages(MIS) 6, 3, 2 and 1. This glacial chronology is in reasonable agreement with existing glacial chronologies from other parts of the Hengduan Mountains and surrounding mountains. Glaciers had extended to the Yuqu River during the glacial maximum advance(MIS 6), but became successively more restricted from MIS 3 to MIS 1. The glacial distribution show that precipitation brought by the south Asian monsoon might play a primary role in driving glacial advances during the last glacial period in the southeastern Qinghai-Tibet Plateau.

Planation Surfaces on the Tibet Plateau,China

A planation hypothesis is proposed to explain landform evolution of the Tibet Plateau.A denudation threshold(T),the maximum potential denudation rate for a certain type of rock,is introduced to explain the combined effects of lithology and tectonics on landform evolution.If the tectonic uplifting rate(U)is equal to or less than the threshold rate(U≤T),the tectonic uplifting and terrain denudation are in dynamic equilibrium,and landforms are in a steady state.The end product should be planation surfaces whether the original landforms are flat plains or deeply dissected mountains.If U>T,uplift and denudation are not able to reach a dynamic equilibrium state.The plateau surface is mostly underlain by soft rocks,such as the Mesozoic epimetamorphic argillites and Tertiary sedimentary rocks,while the mountain ranges comprise hard rocks,such as granite,gneiss and limestone.In soft rock regions,hills are low with a relative relief of mostly less than 100m and the slopes are gentle at a gradient of <20o.In contrast,hills can maintain steep slopes in hard rock regions.The Tibet Plateau has been under an equilibrium condition between tectonic uplifting and denudation except for the mountain ranges.The plateau might have reached the present altitudes before the Quaternary.

Morphology and formation mechanism of sand shadow dunes on the Qinghai-Tibet Plateau

The formation and development of dunes depend on wind-blown sand movement which is affected by the characteristics of sand material, topography, wind regimes and other factors. In this paper, we investigated two sand shadow dune groups in Shigatse and Za＇gya Zangbo of Tibet and an individual dune in Da Qaidam of Qinghai, and analyzed their topographies and morphologies, and the physical characteristics of the sand, wind regime and sand transport. Formed under harsh conditions behind hills, these mature sand shadow dunes are hundreds of meters long, have significant ridges and crescent dunes downwind, and have a hill pass on one or both sides. Wind tunnel experiments revealed that the hill gap and wind velocity are important factors in the formation of these dunes Sand shadow dunes formed only when the gap spacing is two-thirds of the hill height. When wind velocities are 20 m/s, the sand body is divided into two parts. The hill pass allows the transport of sand by wind, creating a ＂nar- row-pipe effect＂, which causes the transported material to gradually accumulate in the center of the shadow zone. We observed that the following are needed for sand shadow dunes to form： （1） strong winds, sufficient sand, suitable obstacles and a dry climate; （2） one or both sides of the obstacle forming the shadow zone must have a hill pass; and （3） the windward side of the obstacle must have a wide, flat area, providing adequate spacing for wind flow and transport of material and the leeward side must have a sufficiently broad, flat area to allow the release of the transported material. Research results on these newly discovered dunes on the Qinghai-Tibet Plateau could contribute to the understanding of dune geomorphology.

Definition of the Quaternary Qiangtang Paleolake in Qinghai-Tibetan Plateau, China

Since the Quaternary, many lakes have been present in the Qinghai-Tibetan Plateau. As peculiar geological processes in the evolution of the uplifting of Qinghai-Tibetan Plateau, the distributions and evolutions of the Quaternary paleolakes in the Qinghai-Tibetan Plateau have been the focus of interest among the international geosciences circle. Comparisons of the newly obtained and existing data from field surveys, remote sensing images, characteristics of tectonic landforms and distribution of the lacustrine strata, the author have, for the first time, defined a large-sized Quaternary Qiangtang Paleolake. The paleolake starts from the east-westerly direction at Rutog in western Tibet, passing through Gerze, and finally ends at Nagqu in eastern Tibet. Its length is approximately 1,200 kin; it is about 420 km at its widest point （north-southerly）. The Paleolake forms an E-W （or NWW） ellipsoid with an estimated area of 354920 km2. The Paleolake is bordered by the Mts. Gangdise and Nyainqentanglha to the south and the Karakorum Pass-Toze Kangri-Zangbagangri- Tanggula Pass to the north. It generally appears as a basinal landform with low mountains and valleys in the central part （altitudes of 4400 m） and higher altitudes （5000 m） in the peripheries. The formation and development of the Paleolake was controlled by the nearly E-W trending structures. There are three east-westerly extending tectonic sutures inside the Paleolake area, from north to south： （1） the Shuanghu Suture; （2） the Bangong Co-Nujiang River Suture; （3） the Shiquanhe-Lhari Suture. These three sutures have generally controlled the spreading features of the Paleolake and act as the first grade lake-controlling structures. In the southern Paleolake basin, there are a series of south-northerly rift basins, which are controlled by the normal faults and exist as a series of south-northerly grabens and semi-graben faulted basins. The south- northerly rift zones have clearly exerted control over the south margin of the Paleolake as well as the distribution of the residual lake basins after the Paleolake＇s break up. They are the secondary lake- controlling tectonics. Discoveries of the lacustrine strata inside the Plateau, especially the successive discoveries of many high-stand lacustrine strata, are direct evidence supporting the existence of the paleolakes in the Plateau. The dating results of the lake-eroded travertine in the Dong Co in the hinterland of the Quaternary Qiangtang Paleolake have revealed that the lake-eroded travertine is of Late Pleistocene sediments. By considering the analysis of the lacustrine strata as well, the researchers have revealed that the Quaternary Qiangtang Paleolake begins its embryonic form in the Early Pleistocene, successively develops till the Middle Pleistocene, and reaches its full blossom in the middle stage of the Late Pleistocene; it further shrinks and separates by the end of the Late Pleistocene, and finally ceases its whole life as the paleolake. After the Holocene, the huge Late Pleistocene Qiangtang Paleolake no longer exists, leaving a series of widely distributed smaller lakes on the Qiangtang Plateau. These smaller, isolated water systems receive the Holocene lacustrine sediments.

Extraction and Analysis of Gully Head of Loess Plateau in China Based on Digital Elevation Model

In China′s Loess Plateau area, gully head is the most active zone of a drainage system in gully areas. The differentiation of loess gully head follows geospatial patterns and reflects the process of the loess landform development and evolution of its drainage system to some extent. In this study, the geomorphic meaning, basic characteristics, morphological structure and the basic types of loess gully heads were systematically analysed. Then, the loess gully head′s conceptual model was established, and an extraction method based on Digital Elevation Model(DEM) for loess gully head features and elements was proposed. Through analysing the achieved statistics of loess gully head features, loess gully heads have apparently similar and different characteristics depending on the different loess landforms where they are found. The loess head characteristics reflect their growth period and evolution tendency to a certain degree, and they indirectly represent evolutionary mechanisms. In addition, the loess gully developmental stages and the evolutionary processes can be deduced by using loess gully head characteristics. This study is of great significance for development and improvement of the theoretical system for describing loess gully landforms.

青藏高原东南缘金沙江下游新生代构造与地貌演化

青藏高原东南缘发育数十万平方千米的广阔地貌过渡带与大面积低起伏地貌面,独特的地貌提供了解读高原构造拓展与地表隆升时间、过程以及机制的理想窗口。为揭示青藏高原东南缘新生代构造变形响应和地貌演化过程,通过构造解析、构造地貌以及低温热年代学数据分析对金沙江下游流域进行综合研究。结果表明青藏高原东南缘早在始新世即已处于北西向为主的区域性挤压条件下而发生广泛褶皱变形。尽管始新世存在区域性变形响应,但青藏高原东南缘金沙江下游地区在古近纪为低海拔丘陵地貌,地表隆升幅度极为有限。晚渐新世—早中新世研究区总体处于长期的低剥蚀速率环境,促进了低海拔平缓地貌的形成。晚新近纪以来,青藏高原东南缘发生区域性缩短变形与显著地表隆升,大型水系同步下蚀,共同塑造形成现今较高海拔的低起伏地貌面与深切峡谷并存的特征性地貌。研究结果支持青藏高原东南缘晚新近纪以来的隆升与地壳构造缩短及增厚密切相关,而中下地壳塑性流动增厚机制并非必不可少。

高原型喀斯特主要丘陵类型、形成机制与贵州喀斯特地貌分区刍议

喀斯特地貌类型和分区受气候、构造、地质背景等多种因素影响,仅以峰林、峰丛等形态组合为基础的地貌分区,难以完全反映贵州复杂的喀斯特地貌。以往的分区工作忽略了除典型锥峰、塔峰外大量分布的“馒头山”丘陵(穹丘)的重要性,其形态特征、空间分布以及形成演化机制等尚不清楚。本文根据贵州喀斯特地貌野外考察结果,结合室内资料综合分析,探讨了贵州不同喀斯特丘陵类型的空间分布规律、形成机制以及与气候、地质(岩性和岩相)等环境背景的内在联系,并结合已有石漠化分区方案,初步提出贵州高原喀斯特地貌分区方案。主要认识如下:(1)锥峰、塔峰、穹丘喀斯特丘陵和常态山非喀斯特丘陵是贵州高原主要的四种丘陵类型。(2)锥峰、塔峰的形成受表层岩溶带溶蚀机制控制,穹丘坡地形态与土壤蠕移有关。(3)贵州除非喀斯特区外,喀斯特区分为锥峰、塔峰喀斯特地貌区,穹丘喀斯特地貌区和喀斯特峡谷地貌区三个大区。(4)锥峰、塔峰喀斯特地貌区包含黔中西部北亚热带浅碟型峰丛(锥峰)洼地区和黔南南亚热带漏斗型峰丛(锥峰、塔峰)洼地区两个亚区。(5)穹丘喀斯特地貌区包含黔东北中亚热带褶皱构造穹丘槽谷区,黔北中亚热带不纯碳酸盐岩穹丘洼地区,黔西北暖温带穹丘洼地、盆地区,黔西西南季风常态山、穹丘洼地、盆地区,黔中东部北亚热带不纯碳酸盐岩穹丘-常态山洼地区五个亚区。(6)喀斯特峡谷地貌区为北盘江深切峡谷多丘陵形态立体分布区。本研究可为喀斯特地区生态建设、区域经济社会高质量可持续发展等提供科学依据。

光伏助推高原乡村振兴的实践探索

以云南省禄劝彝族苗族自治县马鹿塘乡普德村为例,结合当地突出用能问题,探讨光伏发电技术在高原乡村生活用能、基础设施建设和农业发展领域的应用,并分析了所产生的经济、环保和社会效益.

青藏高原东南缘新生代的三期构造隆升——来自河流纵剖面分析的证据

青藏高原东南缘新生代期间经历了多阶段隆升过程,但其主要隆升阶段、时代及其在地貌上的响应等仍不清晰。本文针对金沙江上游流域(石鼓以上),对青藏高原东南缘新生代期间构造隆升的响应过程及特征进行研究,利用数字高程模型,提取分析了金沙江上游段的河流纵剖面形态、集水区坡度和陡峭指数(ksn)等构造地貌指标,发现金沙江上游存在三个主要裂点,将金沙江干流由NW至SE分为曲麻莱、玉树、沙东和奔子栏四个具有不同河道参数的河段。除曲麻莱段外,各段支流河道也可划分为不同的河段,剖面以及河道参数呈现不同的特征,其中上游河段陡峭指数、河道坡度值均为南部大,北部小;中上游与中下游河段,陡峭指数、河道坡度值南北部差异不大;下游河段,地貌上表现为陡峭指数与河道坡度值北部较大,南部较小。此外,在对裂点的成因进行分析后发现,青藏高原东南缘的构造隆升过程是该区河流地貌特征的主控因素。结合前人的热年代学数据,研究认为,金沙江上游的三个区域性裂点的形成可能指示或响应了青藏高原东南缘在新生代以来发生的三期构造隆升事件,且隆升时间从早到晚分别在20~30 Ma、9~15 Ma、3~6 Ma间,这表明构造地貌分析对于揭示区域构造隆升具有重要意义。

青藏高原纳木错异常高湖面重建工作研究进展与展望

青藏高原的许多湖泊发育有湖岸线、侵蚀阶地和高湖面沉积物,这些地貌和沉积单元是反映地质历史时期湖面变化的直接地貌和岩性证据。它们不仅反映了湖泊水文变化历史,还可作为揭示区域乃至全球环境变化的重要载体。在青藏高原众多湖泊中,纳木错最具典型性和代表性。纳木错湖岸最高古湖相沉积物位于现代湖面之上约150 m,高出当今溢流垭口约123 m。至今,有关纳木错异常高湖面的发育时代、湖侵-湖退过程、异常高湖面的形成机制、与其他湖泊之间的水文联系等科学问题仍不清楚或存在很大争议。本文以纳木错异常高湖面的特征、时代、期次和成因问题为主题,综述了一个多世纪以来国内外学者对纳木错湖面变化重建的研究成果,尤其对目前纳木错古湖面重建研究中存在的问题进行了总结,并对未来的工作重点进行了展望。此外,基于初步的调查结果,认为纳木错高湖面沉积可能形成于全新世中晚期,并指示了一次湖侵-湖退过程。南支槽的异常振荡及其导致的冬半年降水增加可能是引起湖面变化的主要驱动因素。

基于SBAS-InSAR技术的西大滩—昆仑垭口地区多年冻土形变分析

多年冻土活动层内部冰-水相变会导致多年冻土地表出现季节性的冻胀和融沉,而其上限处地下冰融化将引起地表的长期沉降,因此揭示地表形变的季节和长期变化规律可为多年冻土变化研究提供新的视角和方法。本文以青藏高原多年冻土区北界(西大滩—昆仑垭口)为研究区,利用C波段降轨Sentinel-1数据,采用SBAS-InSAR技术获取该地区多年冻土2014—2020年的地表形变时间序列结果,并基于长期形变速率和季节性形变量探讨了该地区的多年冻土形变规律。结果表明:在多年冻土北界西大滩沟谷地区,不连续多年冻土区形变空间差异较大,多年冻土区的长期沉降速率和季节性的形变量高于季节冻土区。此外,高温多年冻土地表沉降比低温多年冻土更为显著,形变空间分布特征与地貌单元紧密联系。与西大滩谷地相比,昆仑山垭口地区和楚玛尔河高平原区域的长期形变速率与季节性形变量都明显增大。同时热融湖塘的形成过程与地表形变有着直接的关联,在热融湖塘发展早期,地下冰融化使得区域季节性形变量增大,随着热融湖塘扩张,区域长期沉降速率加剧,热融湖塘进一步发展后,区域季节性形变量可能降低。

典型黄土地貌类型区的地形复杂度分形研究

黄土高原地貌形态与地形复杂度自南向北有序变化,构成了举世瞩目的独特的地理景观。选择陕西省南北剖面六个典型黄土地貌样区为基本实验区,以其1∶1万栅格DEM为数据源,探讨典型黄土地貌类型区的地形复杂度分形与空间分异特征。首先提出的元分维模型方法,以计算得到的DEM元分维值作为特征指标,研究样区的地形复杂度问题。这种通过滑动窗口的扩展分维分析方法,既可以用于分析该区域不同尺度下的地形复杂度变化情况,也可以探讨区域的局部单元复杂程度及其空间分布,从而不再局限于对全区域的单一分维评价。以此为基础,进一步应用元分维谱方法,研究地貌网格单元的元分维分级分布情况。实验结果表明:以绥德和延川为代表的黄土峁状丘陵沟壑区最为复杂,以宜君和甘泉为代表的梁状丘陵沟壑区居中,而以淳化为代表的黄土塬区和以神木为代表的风沙黄土过渡区最为平缓。实验进一步证明了扩展分形方法在黄土地貌研究中的可行性。

黄土高原小流域不同地形下土壤有机碳分布特征

研究了黄土高原小流域尺度塬面、坡地、沟道和梯田4种地形条件下土壤有机碳总量和活性组分的分布、储量及碳库管理指数的差异。结果表明,小流域土壤有机碳和不同活性有机碳的变异系数介于32%—70%之间,表现出中到高度的变异特征。4种地形下各组分有机碳含量和储量以塬面土壤最高,沟道土壤最低,并随土层深度的增加而降低,降低程度随有机碳活性增强而增加。以塬面土壤为对照所获得的碳库管理指数可灵敏指示有机碳对地形条件的响应特征,中活性有机碳库管理指数的指示效果最好。研究结果可部分解释黄土高原土壤有机碳地带性分布特征。

基于DEM的黄土地貌类型提取与制图——以黄土高原丘陵沟壑实验样区为例

以陕北绥德县刘家沟流域为实验样区 ,从地貌成因、形态和土地利用角度出发 ,分析了黄土高原丘陵沟壑区 3种典型地貌类型的区域特征 ;以不同地貌类型的区域特征为基础 ,在地理信息系统平台软件 Arc View的支持下 ,利用数字高程模型 (DEM)自动提取黄土丘陵区 3种基本地貌类型的方法和技术。研究分析结果证明 :利用 DEM自动提取地貌类型是一种快速、高效的技术方法 ,对指导退耕还林。

青藏高原层状地貌特征及其成因初探

青藏高原是全球海拔最高、形成时代最新和面积最广阔的高原,作为青藏高原典型的地貌特征,层状地貌成因研究对高原隆升、环境气候演化过程的认识具有非常重要的作用,通过野外调查和已有观测数据分析,对层状地貌形成进行探讨,重点从高原现今地貌特征分析的角度,提出主平面和山顶面形成于高原隆升过程中。青藏高原是在印度大陆与欧亚大陆俯冲-碰撞的强烈挤压环境下,内外动力地质作用共同作用的结果,其内动力地质作用具有差异性整体隆升的特征。希望能对青藏高原隆升过程的深入研究提供新的思路和依据。

雷达地形测绘DEM用于青藏高原地貌分类

第一次全国地理国情普查工作的一项重要内容就是调查地形地貌。针对在青藏高原等艰险地区开展相应工作仍存在诸多困难,该文基于美国"奋进号"航天飞机获取的SRTM-DEM数据,运用GIS技术提取了青藏高原的8个地貌因子,通过相关性分析最终选取地表粗糙度、高程、地势起伏度、坡度变率及坡向变率5个相关性相对较小的因子,开展宏观地貌类型划分及地貌分布特征分析工作,并基于一种简易模型提取并讨论了对青藏高原生态环境有重要影响的冰缘(冻土)地貌。研究表明:应用SRTM-DEM数据可快速有效地提取青藏高原等艰险地区的地貌因子,但某些因子之间具有极高的相关性,应用中需慎重选择。此外,通过SRTM-DEM数据提取地貌因子以进行宏观地貌类型划分及地貌特征分析的方法简单易行,能够为在青藏高原等艰险地区开展地理国情普查工作提供可靠的基础资料。