Petrogenesis and mineralization potential of a granite porphyry intrusion beneath the Baishan Mo deposit, Eastern Tianshan, NW China

•The granite porphyry beneath the Baishan Mo deposit was intruded at about 228 Ma.•The granite porphyry has an adakitic signature and originates from crust with a high degree of fractional crystallization.•The granite porphyry hints on the existence of a porphyry Cu mineralization system at depth.

The Baishan molybdenum deposit is located in the eastern section of the Jueluotage tectonic belt, Eastern Tianshan. There is a granite porphyry intrusion beneath the Baishan Mo ore bodies discovered by recent exploration drilling, and the Cu–Mo minerals are widely distributed in the porphyry. The zircon LA-ICPMS U–Pb age of the granite porphyry intrusion is 228.1 ± 8.0 Ma, which is in coincidence with the age of Mo mineralization (227.7 ± 4.3 Ma). The granite porphyry intrusion is calc-alkaline and peraluminous. The magma was derived from a lower crustal source, it experienced distinct crystal fraction during its evolution, and the magma intruded in a Triassic compressional background, and was probably influenced by far-field effects of the Tethys system to the south. Based on the geological, geochemical and geochronological characteristics of the granite porphyry intrusion, we propose that there is probably a porphyry Cu deposit beneath the Baishan high-Re Mo deposit.