基于DEM的白龙江流域构造活动定量分析  

APPRAISAL OF ACTIVE TECTONIC IN BAILONGJIANG BASIN BASED ON DEM DATA

作　　者：常直杨[1] 王建[1,2] 白世彪[1,2] 张志刚[1] 

机构地区：[1]南京师范大学地理科学学院,南京210023 [2]南京师范大学虚拟地理环境教育部重点实验室,南京210023

出　　处：《第四纪研究》2014年第2期292-301,共10页Quaternary Sciences

基　　金：国家自然科学基金项目(批准号:40871010);南京师范大学全国优秀博士论文培养项目(批准号:2012BS0005)共同资助

摘　　要：白龙江流域地处青藏高原向黄土高原过渡的斜坡急剧变形带,是我国泥石流、滑坡灾害最为严重的地区之一,由于流域受多条断裂带的影响,内部相对构造活动强度存在差异,因此对该地区构造活动程度的研究显得尤为重要。本文基于SRTM3-DEM数据,利用GIS技术提取了白龙江流域33个子流域的面积高程积分(HI)、河流阶梯指数(SL)、流域盆地不对称度(AF)、流域形状指数(BS)、谷底宽度与谷肩高度比(VF)等5种地貌参数。然后对5种地貌参数进行分级,求取5种地貌参数分级值的算术平均值,作为评价研究区的构造活动程度(Iat),分为弱、中等、较强和强四类。研究结果表明,白龙江流域中上游地区构造活动程度为中等至强(Iat≤2),这与该地区受青藏高原隆升效应及断裂带走滑作用相一致。下游地区构造活动程度相对弱(Iat>2),地貌差异不明显,这与该地区主要断裂带第四纪以来活动性弱有关。研究结果与区域的地质背景相一致,该研究对利用地貌参数进行流域的活动构造量化分析具有借鉴意义。Geomorphic indexes are useful tools for studying different spatial intensity of tectonic activity.Bailongjiang drainage basin with an area about 31808km2 is located in the transition zone between the Tibetan Plateau and the Loess Plateau where it＇s one of the most serious debris flow,landslide disaster area.It originates from Guo＇ermang Mountain and is the largest tributary of the upper reaches of Jialingjiang.The main stream drains from northwest to southeast with the relief more than 2500m,and the length is 576km.Tributaries develop along the main stream such as Baishuijiang,Dalagou,Lazigou,Minjiang and so on.It＇s important to study the tectonic activity due to the impact of different activity faults and the different tectonic activity.Based on the SRTM 3-DEM data and the technique of GIS,several tectonic geomorphic indexes which include stream-gradient index （SL）,hypsometric integral （HI）,drainage basin asymmetry （AF）,drainage basin shape （BS）,valley floor width-valley height ratio （VF） are extracted from 33 sub-basins of Bailongjiang drainage basin.These indexes were combined to yield the relative tectonics index （Iat） using geographic information system.Iat is an index of relative active tectonics,which is obtained by the average of the different classes of geomorphic indexes to access the relative tectonic activity.Based on Iat values,the study area was divided into four parts：Class 1 （very high relative tectonic activity,5.5％ in area,1463km2）; Class 2 （high,54％,14343km2）; Class 3 （moderate,24.1％,6417km2）; and Class 4 （low,16.4％,4363km2）.It shows that the value of Iat （Iat≤2） in upstream and midstream is classified into high and very high,this is due to the impact of uplift of Tibetan Plateau and the activity faults in this region.The downstream of Bailongjiang basin has low activity,and the faults in this region have low activity too.The results are consistent with the geological background.It provides a new perspective for discussing the relati

关 键 词：白龙江流域 地貌参数 数字高程模型(DEM) 构造活动程度 

分 类 号：P931.2[天文地球—自然地理学] P542