Geochemistry of granitoid rocks from Zhejiang Province and crustal evolution—I. Phanerozoic granitoid rocks

Abstract

The Phanerozoic granitoid rocks include the Caledonian, Indosinian and Yenshanian granitoid rocks. The existence of Caledonian and Indosinian granites was evidenced by zircon U-Pb ages. The study of the characteristics of major, trace and rare-earth elements, isotopic composition and petrogenesis for the granitoid rocks has been made. The Caledonian and Indosinian granites were derived from partial melting of the Proterozoic basement rocks and the two tectonic activities were weak. The Yenshanian granitoid rocks were derived from mixing of mantle and crustal materials. It implies that the crustal accretion took place in Mesozoic time.