基于ETM+和CBERS数据的甘肃北山音凹峡地区镁铁超镁铁岩体识别

Lithological Discrimination of the Mafic-ultramafic Complex,Yin' aoxia,East Beishan,Gansu,Using ETM+and CBERS Data

镁铁—超镁铁质小岩体易被地质填图遗漏,严重制约了该类型矿化的发现。以甘肃北山音凹峡地区为研究区,首先利用比值法、最小噪声分离法处理ETM+数据增强镁铁—超镁铁质岩体;对于规模较小的小岩体,采用ETM+和中巴资源卫星02BHR数据进行分辨率融合后进行解译、识别。通过将上述3种方法处理结果综合分析后共解译出6处镁铁—超镁铁岩体集中区。经野外检查,6处区域均与遥感分析结果吻合,证实了方法的有效性。该方法可以为西部地区地质填图和镁铁—超镁铁岩相关矿产资源勘查提供借鉴。

Small mafic-ultramafic intrusions were often omitted because of their small sizes and the large distance between two adjacent routes for geological mapping,which has seriously restricted the discovery of the relevant mineralization.This research takes Yin' aoxia,east Beishan,Gansu,as the study area.First,band ratio and minimum noise fraction were adopted to enhance and identify the mafic-ultramafic rocks using ETM+data.Then,ETM+data and CBERS 02BHR were fused to identify and interpret small intrusions.The results were compared with the geological map and conformed to be consistent with the geological map of the study area.Six new regions for mafic-ultramafic intrusions were identified by synthetic analysis of remote sensing results and geological data.Through ground inspections,all the six regions were consistent with the remote sensing results.These methods are recommended for geological mapping and small intrusion-type mineral resources targeting in the sparsely vegetated arid region of northwestern China.