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The Bazman granitoid complex (BGC), including a large zoned pluton, intrudes into the upper Paleozoic sedimentary cover of the Lut block. It crops out on the southern slope of the Bazman volcano in Baluchestan Province of Iran. The intrusive rocks range from gabbro to various metaluminous to weakly peraluminous granites, and they are classified as I-type magmatic series. They display geochemical characteristics of typical volcanic arc magmatism at continental margins. Major- and trace-element variation diagrams show that fractional crystallization was the major process and crustal contamination, a subordinate process during the evolution of the BGC. The decrease in CaO, MgO, Al2O3, Fe2O3, TiO2, P2O5, and Sr, as well as the increase of K2O and Rb with increasing silica, are possibly related to the fractionation of plagioclase, hornblende, apatite, and titanite, whereas the increasing K, Rb, Cs, Pb, and light rare earth elements (LREEs) can be explained by crustal contamination. The BGC rocks are enriched by large ion lithophile elements (e.g., Rb, K, Cs) and the LREEs with respect to the high field strength elements (e.g., Zr, Hf, Nb, Ta, Y) and heavy rare earth elements. New ID-TIMS U-Pb dating performed on zircon and titanite extracted from the granitic samples indicates that the BGC was emplaced during the late Cretaceous period at 83-72 Ma by subduction of the Neo-Tethyan oceanic crust beneath the Eurasian continent. Subsequently, the complex became part of the Lut block when it probably rotated counter-clockwise with respect to the Sanandaj-Sirjan zone and the Urumieh-Dokhtar volcano-plutonic belt. [ABSTRACT FROM AUTHOR]

Mahour polymetal ore deposit is located in the eastern margin of Lut block, 130 Km west of Nehbandan. The supergene mineralization mainly occurs as a north-south trend in the Tertiary altered volcanic rocks. The supergene minerals mainly occur as iron hydroxide, Cu-carbonates, Cu and Pb sulfates and Cu sulfides. Goethite, malachite, azurite, chalcosite, covellite, linarite and atacamite are common supergene minerals in the Mahour ore deposit that were formed by oxidation of the hypogene sulfides. Some of these minerals were analyzed by electron probe microanalyses (EPMA). Ag content is considerable in most of these minerals. Covellite from the Mahour has high Pb, Zn and Ag contents. The chemistry of the supergene minerals and the way of their formation will be discussed in this paper. [ABSTRACT FROM AUTHOR]