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[Display omitted] • Two fundamental types of collisional orogens have been proposed. • Cold orogens are characterized by brittle fault systems and limited magmatism. • Hot orogens are characterized by ductile flow and widespread partial melting. • MVT Pb–Zn and orogenic gold deposits can occur in both cold and hot orogens. • Porphyry Cu deposits are only associated with hot orogens. It is commonly believed that the thermal regime of collisional orogens evolves from cold to hot with time. Here, we compare the Alpine and Himalayan-Tibetan orogens in terms of their thermal regimes recorded in metamorphic rocks, volcanic suites and related xenoliths, and main mineralization types. The results highlight the fact that the Alpine orogen mostly remained in a relatively cold regime from oceanic subduction to post collision stages. In contrast, most of the Himalayan-Tibetan Plateau rapidly reached and was maintained in a relatively hot regime during the whole course of the collision, except for narrow plate boundary domains. We therefore propose that the thermal regime of collision is inherent to a given geodynamic setting, and that the Alpine and Himalayan-Tibetan orogens represent two fundamental types of collisional orogens, cold and hot, respectively. The main mineral deposit types within collisional orogen include Mississippi Valley type Pb–Zn, orogenic gold, and porphyry Cu deposits. The Mississippi Valley type Pb–Zn and orogenic gold deposits can occur in both cold and hot orogens but porphyry Cu deposits are only associated with hot orogens. Major factors that influence the thermal regime of collisional systems include the rate of continental subduction, the rheology of the underlying lithospheric mantle, the thickness of the overlying lithosphere and radiogenic heat production. Here we propose the removal of suborogenic mantle lithosphere and upwelling of asthenosphere also plays an important role on the thermal structure of collision zones. These processes disturbe the thermal balance of the orogens and cause widespread partial melting of the crust, resulting in the formation of magma-related deposits (i.e., granite-related W-Sn deposits and porphyry Cu deposits). We further give a brief overview of other examples around the globe, such as Pyrenees and Caledonides that reperesent cold orogens versus Variscan and Zagros-Iranian Plateau exemplifying hot orogens. [ABSTRACT FROM AUTHOR]

Porphyry Cu (Mo–Au) deposits in the Himalayan–Tibetan orogen formed during the Late Triassic, Early Cretaceous, Eocene, Oligocene, and Miocene and can be classified into different metallogenic belts according to their petrologic features, mineralization ages, and tectonic settings. A close spatial relationship to regional strike–slip faults is evident in all five belts. Porphyry Cu (Mo–Au) deposits exist in a wide range of tectonic environments, including island arc, syn-collision, post-collisional convergence, and continental-transform plate boundaries. Porphyry Cu deposits cluster in the southernmost part of the Yidun–Zhongdian Belt, along the N–S-trending Gaze River dextral strike–slip fault. Porphyry Cu deposits in the Lijiang–Jinping Belt lie along the Ailaoshan–Red River continental–transform shear zone and the associated strike–slip faults. The Yulong–Malasongduo porphyry belt is controlled by the Cesuo Fault, a NNW-trending regional dextral transcurrent fault that is associated with Palaeogene westward continental oblique subduction along the Jinsha suture. In the Gangdis Belt, Miocene porphyry Cu deposits are localized along N–S-trending normal faults, which were produced by transpression within the regional NW–SE-trending Karakoram–Jiali fault zone (KJFZ). A close spatial relationship between porphyry Cu deposits and strike–slip faults also exists for the Bangong–Nujiang Belt. [ABSTRACT FROM PUBLISHER]