Juxtaposition of different-grade metamorphic rocks in an ancient orogen: Evidence from the Chengde Complex of the Trans-North China Orogen, North China Craton

Juxtaposition of different-grade metamorphic slices is a typical feature Phanerozoic orogens but relatively scarce in Precambrian orogens. Here, we focus on the Chengde Complex at northern segment late Paleoproterozoic Trans-North China Orogen, North Craton as case, to explore how orogeny-related metamorphism was juxtaposed The Orogen collisional orogen and records abundant information about orogeny. High-pressure (HP) mafic granulite two types amphibolite samples were collected from Complex, conducted combined study involving litho-structural assemblage investigation, petrology, geochronology decipher their P-T−t history. HP occur enclaves or dikes within felsic gneisses. clockwise P-T paths with isothermal decompression (ITD) segments, peak conditions are 13.0−14.9 kbar/790−830 °C. Peak retrieved garnet-bearing 8.3 kbar/675 °C, whereas garnet-free 4.0−5.5 kbar/500−510 Zircon U-Pb dating yield different prograde (1914−1871 Ma), (1869−1816 retrograde (ca. 1830 Ma) ages, all these data indicate that rocks diachronously transferred depths subduction channel subsequently exhumed shallower crustal levels. Therefore, conclude composed imbricate grades such an unordered juxtaposition diverse could also be