U-Pb zircon ages for the Luzhenguan Complex in northern part of the eastern Dabie orogen

• 作 者: JIANG Laili Wolfgang Siebe CHE
• 机 构: Geological Survey of Anhui Province,Institut für Geowissenschaften,Institute of Geology and Geophysi
• 出 处: 中国科学D辑
• 发表日期: 2004年期
• 关键词: Dabie orogen Luzhenguan Complex U-Pb zircon age Neoproterzoic
• 基金项目: 国家自然科学基金;国家重点基础研究发展计划(973计划)

The study presents U-Pb zircon ages for granitic gneiss and amphibolite from the Luzhenguan Complex (LZC) in northern part of the eastern Dabie Orogen and their geological significance. Two granitic gneisses and one amphibolite give protolith zircon U-Pb ages of 740 Ma and 725 Ma, respectively. The ages show that the LZC is composed mainly of Neoproterzoic acid and basic igneous rocks, suggesting that there is no Paleozoic active continental marginal rock association in the southern margin of the North China Block in northern part of the eastern Dabie Mountain. Based on the ages and combining the geological and geophysical analyses, the middle-low grade metamorphic rocks in the North Huiyang Belt (NHB) can be divided into three parts, which are the LZC composed mainly of the Neoproterzoic acid and basic igneous rocks, the Neoproterzoic Xianrechong Formation and Xiangyunzhai Formation and the Devonian Zhufoan Formation and Pangjialing Formation of the Foziling Group, and the suture zone between the Yongtze Block and the North China Block is inferred to be thrust under the NHB.