奥维地图遥感影像在威信地区1:5万地质填图中的应用

Application of remote sensing image based on the Ovi map to 1:50,000 geological mapping in the Weixin area

滇东北威信一带位于云贵川三省交界附近,构造样式上属侏罗山式褶皱区,以沉积地层为主,因岩石力学性质和风化程度不同,各地层岩石组合和地质地貌的遥感影像特征具有显著差异。以本区不同年代的岩石地层、地貌类型及线性构造为研究对象,利用奥维地图不同比例尺的遥感影像数据进行解译,并结合地质填图过程中的实地验证,明确本区特定地层、岩石和构造的影像特征,并以此为基础,实现了填图路线的合理布局、岩性变化的预判、岩溶地貌类型的划分和地质图的成图处理等工作。通过奥维地图遥感影像的解译工作,地质体界线定位精度较高,可满足1∶50 000区域地质填图要求。

The Weixin area is located in northeastern Yunnan, near the junction of Yunnan, Guizhou and Sichuan provinces,hosting Jurassic mountain-type folds. The rocks in the area are dominated by sedimentary rock formations which host the backbone of the Jurassic mountain-type folding structures. Because of distinct mechanical properties and weathering degree of the rocks, there are obvious differences in the manifestation of the rock assemblages on re mote sensing imagery. The purpose of this paper is to explore the feasibility of applying Ovi remote sensing images and their interpretation to geological mapping in special geomorphic areas. Taking lithostratigraphic units, geomorphic types and linear structures of different ages into account, we use the Ovi remotely sensed data of different scales to con ducted geological interpretation. Moreover, the remote sensing image characteristics of specific strata, rocks and struc tures in this area were then validated through field observation. Based on the results from the imagery interpretation, we could reasonably perform the layout of mapping routes, prediction of lithological changes, division of karst landform types and the preparation of geological maps. This work demonstrates that using the interpretation of remote sensing images on the Ovi map permits to delineate high-precision geological boundaries which can meet the requirements of 1∶50,000 regional geological mapping.