胶东地区早白垩世崂山期花岗岩

Early Cretaceous Laoshan Granite in Jiaodong Area

摘要:

崂山期花岗岩是胶东地区广泛分布的中生代花岗岩之一，形成年龄为108～118Ma。崂山期花岗岩形成于弧后拉张环境，是中国东部中生代构造体制转换结束期岩浆事件的产物，受区域构造控制，为地壳深部岩浆沿NE向断裂上侵就位。该期花岗岩具有高硅、富碱，贫Fe、Mg、Al，贫Sr、Ba、Ti、P，并具有显著的负Eu异常，Ga/Al比值高，是中国东部中生代早白垩世晚期下地壳重熔型花岗岩——A型花岗岩，属弱过铝质高钾钙碱性岩。崂山期花岗岩超动侵入伟德山期花岗岩和早白垩世陆相沉积地层，常与伟德山期花岗岩伴生构成IA型复式杂岩体。

Abstract:

Laoshan graniteis is one of Mesozoic granites widely distributed in Jiaodong area with a formation age of 108~118Ma. It was formed in a backarc tensional environment,which was the product of the magmatic event at the end of the Mesozoic tectonic system transformation，Affected by regional structural control, magma in the deep crust is invaded along the NE trending fault. Laoshanperiod granite is characterized by high silicon, rich alkali, poor in Fe, Mg, Al, poor in Sr, Ba, Ti, and P, and has a significant negative Eu anomaly, and high Ga/Al. It is a lowcrust remelting granite——A type granite of the late Early Cretaceous Mesozoic in eastern China, which belongs to weak peraluminous, highpotassiumcalcalkaline rock.Laoshan period granite intruded into Weideshan period granite, Linglong period granite, ancient metamorphic basement and early Cretaceous continental sedimentary strata, it is often associated with Weideshanperiod granite to form ⅠA type compound complex.