Chapter 3.5 Eoarchean Rocks and Zircons in the North China Craton

Publisher Summary This chapter discusses the various aspects of Eoarchean rocks and zircons in the North China Craton (NCC). Anshan, located in the northeastern part of the Eastern Block, is the area of the oldest rocks in the NCC outcrop. In this area, three different types of 3.8 Ga rocks have been discovered: the Baijiafen mylonitized trondhjemitic rocks, the Dongshan banded trondhjemitic rocks, and the Dongshan meta-quartz diorite. Situated in the Dongshan park in Anshan, the Dongshan complex extends in a nearly E–W direction with a strike length of >1000 m and is commonly less than 10 m wide, between the 3.1 Ga Lishan trondhjemite and 3.0 Ga Tiejiashan granite. The Caozhuang rock series is distributed in the vicinity of Huangbaiyu in the southern part of the Qi’an gneiss dome in eastern Hebei Province. It consists of amphibolite, biotite-plagioclase gneiss, banded iron formation (BIF), fuchsite quartzite, impure marble, biotite schist, and barium-adularia-bearing gneiss. It is found that the Precambrian basement exposed in the Dengfeng–Lushan–Xinyang area in the southern segment of the Trans-North China Orogen is Paleoproterozoic to Neoarchean in age.