Detection of Hydrothermal potential zones using remote sensing satellite data in Ramand region, Qazvin Province, Iran

Abstract

Ramand region is a part of Qazvin province located in South West of Buin-Zahra. In this region, hydrothermal alterations have been extended within magmatic occurrences and therefore are mostly detectable by remote sensing techniques. Altered facies could be well enhanced after applying Selective Principle Component Analysis (SPCA), Least Squares Fitting method (LS-Fit) and Spectral Angel Mapper (SAM) techniques on ASTER images. Remotely sensed photomaps can be created from such bands for detecting argillic and Fe-oxide overlapped alterations as unique but important traces of hypogenic environments. SPCA result showed that Ramand alteration spectrum reflects an orange to yellowish color that is casually indicated to mineralization potential surrounded by clayey and Fe-oxide aggregate halos. Also an advanced Silicification process has been detected within igneous units and subsequently suggested for more prospects according to satellite images. Our research has been introduced to identification of mineralization by using an expert SPCA technique issued by Crosta. Also we have verified PCA results with applying LS-Fit and SAM techniques respectively. These techniques not only realized the post-magmatic alterations but are suitable for spatial prognosis of ore-bearing mineralization respect to their paragenetic appearances. Finalized photomaps have been improved by mathematical algorithms before targeting Ramand alterations for fast field observations due to economical (minimal) sampling in performances.