甘肃北山白峡尼山地区多源遥感岩性制图研究

甘肃北山地区地质构造复杂，岩浆活动强烈，该区工作程度较低，已有1：20万、1：5万地质图对区内岩性（如中酸性侵入岩）圈定较为笼统，且界线不够准确。以甘肃北山白峡尼山地区为研究区，利用彩色空间变换（IHS）、Brovey等方法对ETM多光谱图像与资源三号（ZY3）全色波段高分辨率图像进行空间分辨率融合，获得兼具ETM光谱分辨率与资源三号空间分辨率之长的高分辨率图像。再对原始影像进行比值、主成分分析及假彩色合成等增强处理，突出其岩性差异，将各种方法处理的影像与数字高程模型（DEM）数据结合构建三维影像，进行综合解译。对解译结果进行野外验证、样品薄片鉴定及反射光谱特征分析，据此对结果进行修正，获得了研究区遥感解译地质图。结果表明：对于西部基岩露头较好地区，利用多源遥感数据融合可更新现有地质图，为后续填图、找矿工作提供参考。

Study on Multi-Source Remote Sensing Lithologic Mapping in Baixiani Mountain Area of Beishan,Gansu Province

The geological structure of Beishan area in Gansu Province is complex， and the magmatic activity is intense. Due to the low level of work in this area， the 1∶200 000 and 1∶50 000 geological maps have been used to delineate the lithology （such as medium-acid intrusive rocks） of the Beishan， Gansu， but the boundaries are not accurate enough. Taking Baixiani Mountain in Beishan as the research area， the ETM multi-spectral image and the ZY3 panchromatic high spatial resolution image were fused by color spatial transformation （IHS）， Brovey and other methods to obtain the high-resolution image with both ETM spectral resolution and ZY3 spatial resolution. Then the raw image was enhanced by ratio， principal component analysis and false color synthesis to highlight the lithological differences. The images processed by various methods were combined with Digital Elevation Model（DEM） data to construct 3D images for comprehensive interpretation. Based on the field verification of the interpretation results， sample thin section identification and reflection spectrum characteristic analysis， the results are modified to obtain the geological map of remote sensing interpretation in the study area. The results show that the existing geological maps can be updated by using multi-source remote sensing data fusion in western areas with good outcrop of bedrock， which can provide reference for subsequent mapping and ore-prospecting.