Abstract: This work was made on the basis of data on the interpretation of false color den-site slicer, the fracture profiles, tectonite, fault gouge obtained from the investigations along the middle and southern segments of Tancheng-Lujiang fault zone as well as the studies of Quaternary active faults. Part of data cited here came from previous works on regional geology and geophysics. Some topics, such as the extension, deep geological features, tectonic movement, evolution history and current activity of these segments of the fault zone concerned in which the interest is growing, are dealt with in this paper.From our research results we come to a preliminary idea that the Tancheng-Lujiang fault zone in East China is a complex fault zone which has been undergoing a long tectonic activity and following intense reformation and that it is one of the main fault zones controlling the occurrence of strong earthquakes in East China. The constitution and deformation characteristics of both bottom and cover of this fault zone are sharply different each other on its opposing sides.The oldest trace showing the activity of this fault zone can be found in the Archaean Taishan Group being occurred in the host whithin this zone.The schitosity of Taishan complex along this zone shows an obvious local left-lateral drag which is also found in the Dabie Group (metamorphic series of rocks) along the SE foothills of Mt. Dabieshan. This explains the significant horizontal displacement along this fault zone during the Pre-Sinian period.From the Sinian period up to the Late Triassic period, in the Yangtse block fault running on the eastern side of this fault zone deposited marine sediments, while the north Jiangsu-east Shandong region was uplifting for a long time. From Late Protero-zoic to Early Cenozoic in the vast area west of this fault zone were developed North China type of marine sediments which were followed by the continental sedimentation.In the Mesozoic time the activity of this fault zone only occurred from the Indo-Chinese to the Yanshanian ages with the dominance of the latter. Judging by the met- amorphic series of rocks found on the northern foothills of Dabieshan and Jiaonan County, we can eatimate that the amount of displacement here is 520km in total. In fact it can be regarded as a resultant amount of displacements from lots of tectonic movements in the geological history, partly belonging to the Proterozoic, partly to the Hercy-nian and Indo-Chinese left-lateral strike-slip.The Himalayan movement probably caused the change of Tancheng-Lujiang fault zone activities in nature, from left-lateral displacement into right-lateral with thrusting movement. There ia an evidence that this fault zone was active in Cenozoic and shows a clear lineament on the satellite images with contrast shade. The other evidences are .as follows: the development of fault gouge with new stria and schistose texture and clastic materials. In addition, the geomorphological features and gravity anomaly also .show its tectonic activity during the Cenozoic period.The Cenozoic right-lateral strike-slip along this fault can be followed obviously, particularly on the Malingshan western slope, Tancheng County. And the right-lateral reversed phenomenan along this fault can be observed in the place where the small co-ombes run through the fault with the offset reaching 25m. As a result, the diabase vein formed in the Late Tertiary was offsetted and dragged by this fault. The solution of mechanism of earthquake also reveals the fact that the fault is still subjected to the right-lateral strike slip.The left-lateral, right-lateral as well as tensile and compressive displacements along the fault imply that throughout the long history of the Tanlu fault, the fault has had larger displacement. This may explain why the fault is such a prominent feature. This change of displacement as a function of time along major faults may de characteristic of intraplate deformation.

摘要： 本文根据卫星影像、断层泥的分布和特征、重力资料、地震分布和震源机制资料以及其他某些地质资料,讨论了郯庐断裂带前震旦亚代以来的活动情况和现代活动性,并认为沿此断裂带现存达几百公里的左旋走滑位移量,应是地史上历次断裂运动的最终结果。指出了值得继续研究的课题。