基于多源遥感数据的高山峡谷区岩性信息提取研究——以新疆乌什县北山1:50000填图试点为例

新疆乌什县北山1∶50000填图试点项目位于塔里木盆地西北边缘和西南天山交接部位,海拔较高,地形切割较深,属于典型的高山峡谷区。利用ASTER、SPOT6、GF-2等多源遥感数据,基于典型岩性光谱吸收特征,进行岩性差异信息增强与提取研究,总结出一套基于多源遥感数据进行岩性单元边界划分的方法。以ASTER数据、ASTER与SPOT6协同数据、ASTER与GF-2协同数据等为基础影像数据,并选择最佳波段组合进行RGB彩色合成,从而增强影像差异,结合已有研究区地质资料,初步圈定不同影像单元边界;继而利用矿物丰度指数、SMACC端元丰度提取等方法识别研究区内主要岩性的分布位置和范围;最后结合野外实际调查数据,依据实际地质背景和影像质量进行筛选,获得最终的岩性单元解译图。研究结果为该区进一步进行地层优化划分及对比提供了参考资料。

LITHOLOGICAL INFORMATION EXTRACTION IN MOUNTAIN CANYON REGION BASED ON MULTI-SOURCE REMOTE SENSING DATA: A CASE STUDY OF 1: 50000 PILOT GEOLOGICAL MAPPING IN BEISHAN AREA IN WUSHI, XINJIGAN

The location of 1:50000 pilot geological mapping program in Beishan, Wushi County, lies at the junction point of north-west margin of Tarim basin and south-west of Tianshan. According to the geomorphic characteristics of high altitude and deep negative relief, the study area belongs to alpine valley region. Based on the typical lithology spectral absorption characteristics, we carried out some research on the enhancement and absorption of lithologic differences information, and summarized a series of methods to divide the lithological units margins according to multi-source remote sensing data. On the foundation of ASTER, ASTER and SPOT6 cooperative data, ASTER and GF-2 cooperative data, we choose the best wave combination to synthesize RGB color and enhance the difference between images. And we preliminarily mark the boundaries of different image units according to the known geological data of study area. Then, the final lithology units can be interpreted by combining field survey data, realistic geological background, and geomorphic images. Thus, the study results provide reference for further optimized stratum division and comparison.