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A large‐scale high‐pressure granulite belt (HPGB), more than 700 km long, is recognized within the metamorphic basement of the North China craton. In the regional tectonic framework, the Hengshan‐Chengde HPGB is located in the central collision belt between the western block and eastern block, and represents the deep crustal structural level. The typical high‐pressure granulite (HPG) outcrops are distributed in the Hengshan and Chengde areas. HPGs commonly occur as mafic xenoliths within ductile shear zones, and underwent multipile deformations. To the south, the Hengshan‐Chengde HPGB is juxtaposed with the Wutai greenstone belt by several strike‐slip shear zones. Preliminary isotopic age dating indicates that HPGs from North China were mainly generated at the end of the Neoarchaean, assocaited with tectonic assembly of the western and eastern blocks.

Abstract The Archaean lower crust represented by granulite facies rocks, which is rare in China, is found to be exposed in the Shanxi‐Hebei‐Inner Mongolia border region. Studies of the regional structure and deformation and metamorphism of the region indicate that there occurred at least two phases of deformation and metamorphism in the region. Early‐phase nearly E‐W‐directed deformational structure is well preserved in the Zhangjiakou‐Xuanhua area. Observations of the features of the geological structure from north to south (in the Hengshan metamorphic terrain) have revealed a possible exposed cross‐section through the Archaean lower crust. The structure was superimposed by a NE‐SW‐trending high‐temperature ductile shear zone in the Datong area in the late phase, thus reworking the Archaean sequence.

The ultra‐long electromagnetic wave remote sensing technique developed by Peking University is one of new future techniques, which can detect the submarine geological information from the depth of 20 to 10000 m below the surface by receiving natural ultra‐long electromagnetic waves (n Hz to n 100 Hz). The new remote sensor is composed of three parts: a main instrument with a portable computer, an antenna with an amplifier and an external power.