Geochronology and Geological Implications of Paleoproterozoic Post-Collisional Monzogranitic Dykes in the Ne Jiao-Liao-Ji Belt, North China Craton

Hardly any previous studies have focused on the granitic dykes which intrude into Paleoproterozoic Liaohe Group in Liaodong Peninsula, northeast of North China Craton. In situ zircon U-Pb dating, Lu-Hf isotopic and geochemical analyses three representative monzogranite were taken this study. These relatively high content SiO2 (72.20%–74.78%) K2O (2.83%–6.37%), characteristics high-K calc-alkaline to shoshonite series. Two dyke samples I-type granite features Sr/Y ratios positive Eu anomalies, showing an adakitic feature. Another has a ratio Ga/Al, but low Zr saturation temperature, differs from typical A-type granite. Zircon grains these magmatic zoning CL images yield consistent ages ~1859–1852 Ma, are interpreted as crystallization dykes. Hf mainly negative εHf(t) values TDM2 2782–2430 similar those 2.2–2.1 Ga granitoids meta-sedimentary rocks (the Group), indicating monzogranitic may been sourced melting rocks. The generated under post-collisional geological setting after Jiao-Liao-Ji orogeny process.