Geochemical Characteristics and Zircon U-Pb Isotope Age of the High-pressure Basic Granulite in the Xiyanghe Area of the North China Craton

The high-pressure granulite exposed in the north-central part of north China is of great significance to the study of the Neo-Archaean-Palaeoproterozoic structural evolution of the north China craton. This thesis researched and discussed the geological, geochemical, metamorphic and U-Pb isotope ages of zircon in high pressure basic granulite, which newly discovered in the huaian complex in the xiyanghe area of huaian county. Though it, we concluded that the high pressure basic granulite was determined to be a basic magmatic source(gabbro or basalt), which has the geochemical characteristics of MORB type basalt, and its formation age was earlier than 2 162Ma. The rock has mainly undergone the geological transformation of high-pressure granulite facies metamorphism in the peak period and metamorphism in the later period, and with metamorphic ages of 1 925 Ma and 1865 Ma respectively, which reflected the Neoarchean-Palaeoproterozoic collision orogenic process and provided new evidence for studying the structural evolution of the North China Craton.