Abstract:It is known that Mesozoic magmatism generated a series of granitic plutons in the northern segment of the Taihang Mountains. Among others, the Mapeng-Chiwawu pluton just crops out in the central part of the Neoarchean-Paleoproterozoic Fuping Complex, showing I-type calc-alkaline affinity, with low SiO2 and high Al2O3 and alkali content. The pluton consists of quartz diorite, granodiorite and granite from edge to core, and these intrusions yielded LA-ICP-MS zircon U-Pb ages of 126.4±2.4 Ma, 125.4±2.0 Ma and 126.2±2.0 Ma, indicating that the pluton was emplaced in a short time around 126 Ma (Early Cretaceous). The total amount of Al in hornblende is 1.018, 0.880 and 0.871 for quartz diorite, granodiorite and granite, and accordingly the crystallization pressure of hornblende is 0.183, 0.118 and 0.114 GPa, with an average of 0.141 GPa, indicating a depth of ca. 5 km. This is significantly smaller than the thickness of Proterozoic to Jurassic sequences around the Fuping Complex, suggesting a dome-shaped structure for the Fuping Complex before the Early Cretaceous. Combined with other data, an average uplift rate of 0.07~0.08 km/Ma can be obtained for the Taihang Mountains since the Early Cretaceous.