TECTONIC CHARACTERISTICS OF THE CENTRAL SEGMENT OF THE TANCHENG-LUJIANG FAULT ZONE, SHANDONG PENINSULA, EASTERN CHINA

The Tancheng-Lujiang fault zone (TLFZ), in the central segment in the Shandong Peninsula, eastern China, is composed of four major faults, c alled F1-F4 from east to west, forming a. 50-km-wide zone. Detailed fi eld study demonstrates that Neogene volcanic and sedimentary strata, Q uaternary deposits, and topographic surfaces cover the fractured zones of faults F3 and F4 and are not deformed or displaced. The same rocks and surfaces on faults F1 and F2, however, are clearly displaced. The geological and seismological data show that the F1 and F2 are present ly active as a major seismic zone in eastern China, whereas the F3 and F4 have been inactive since the Neogene. Fabrics of foliated cataclas tic rocks generated in the fracture zones show left-lateral strike-sli p on the F3 and F4 between Cretaceous and Neogene time, and high-angle reverse or normal faulting, with a dextral component, on faults F1 an d F2 in late Quaternary time. Field evidence and analysis of the fabri cs of fault-related rocks reveal the changes of shear sense and activi ty of faults F1-F4 of the central segment of the TLFZ from Cretaceous to Quaternary time in the Shandong Peninsula. (C) 1998 Elsevier Scienc e B.V. All rights reserved.