Single zircon ages from high-grade rocks of the Jianping Complex, LiaoningProvince, NE China

The high-grade rocks of the Jianping Complex in Liaoning Province, NE China , belong to the late Archaean to earliest Proterozoic granulite belt of the North China craton. Single zircon ages obtained by the bb-bo evaporation m ethod and SHRIMP analyses document an evolutionary history that began with deposition of a cratonic supracrustal sequence some 2522-2551 Ma ago, follo wed by intrusion of granitoid rocks beginning at 2522 Ma and reaching a pea k at about 2500 Ma. This was followed by high-grade metamorphism, transform ing the existing rocks into granulites, charnockites and enderbites some 24 85-2490 Ma ago. The intrusion of post-tectonic granites at 2472 Ma is assoc iated with widespread metamorphic retrogression and ends the tectono-metamo rphic evolution of this terrain. A similar evolutionary sequence has also b een recorded in the granulite belt of Eastern Hebei Province. We speculate that the Jianping Complex was part of an active continental margin in the l ate Archaean that became involved in continental collision and crustal thic kening shortly after its formation. There is a remarkable similarity betwee n the similar to 2500 Ma North China granulite belt and the equally old gra nulite bell of Southern India, suggesting that the two crustal domains coul d have been part of the same active plate margin in latest Archaean times. (C) 1998 Elsevier Science Ltd. All rights reserved.