Monzogranitic porphyries at Tongkuangyu Cu deposit were emplaced ca. 2180 Ma.
They formed by remelting of ∼2.7 Ga diorite with minor juvenile mantle material.
Low ƒO2s (ΔFMQ −1.5) make them unsuitable for porphyry type mineralization.
A new geodynamic model (2.7–2.2 Ga) is proposed for the Zhongtiao Mountain.