چکیده
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This study uses remote sensing image-processing to enhance
recognition of areas with mineral abundance halo, which can be
associated with porphyry mineralisation of the Urumieh-Dokhtar
Magmatic Belt (UDMB) in western Yazd. Granitoid intrusions of
Oligocene-Miocene age in UDMB hosts the most important
Porphyry Copper Deposits (PCDs) of Iran such as Darezereshk
and Aliabad PCDs. Diagnostic spectral absorption features of six
shortwave infrared (SWIR) and three visible and near-infrared
(VNIR) bands of the Advanced Spaceborne Thermal Emission and
Reflection Radiometer (ASTER) data were applied to determine the
alteration minerals and their abundance. In this research reflectance
data from various representative alteration types throughout
the study area were measured by the FieldSpec-3
spectroradiometer and applied for mapping minerals. Different
remote sensing analytical techniques, including the Principal
Component Analysis (PCA), band ratio, relative absorption band
depth, and MTMF, were applied to enhance mapping the alteration
minerals. Field works including rock sampling, petrography
and field spectroradiometer followed up the alteration mapping.
Field observation implies that, the vein-type mineralisation above
the cupola of this porphyry system is preserved in the western
part, although it was eroded in the eastern area. Consequently,
PCDs potential is expected to be higher in the western area.
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