Application of Crosta technique for porphyry copper alteration mapping, using ETM+ data: A case study of Meiduk and SAR Cheshmeh areas, Kerman, Iran  H. Ranjbar Department of Mining Engineering, Shahid Bahonar University of Kerman, Iran, Post box No. 76135-133, Tel and Fax: +98-341-2112764, E-mail: hranjbar64@yahoo.com M. Honarmand, Z. Moezifar Department of Geology, Shahid Bahonar University of Kerman, Iran G. S. Roonwal Department of Geology, Delhi University, Delhi-110007, India, E-mail: gsroonwal@hotmail.com Abstract: Many of the known porphyry copper deposits are situated in the Central Iranian volcanic Belt. The area under study is located in the southern part of this belt and covers an area of about 2600 sq. kms. The climate in the area is a semi arid type. Given the poor soil development but abundant outcrops, the arid/semiarid part of the belt is suitable for remote sensing study. ETM+ images have been used for alteration mapping. Crosta method was found useful for enhancing the areas with hydroxyl and iron oxide minerals. Crosta method has been used on selected 4 and 6 bands. The areas with iron oxide and hydroxyl minerals are enhanced by this method. However the areas with higher grade of alteration are enhan ced by using six bands of ETM+ images. |