STUDY ON THE NEOTECTONIC ACTIVITY OF THE FRENCH CENTRAL PLATEAU
法国中央高原的新构造活动研究

The French Central Plateau Massif, dipping very gently to the northwest, is located in the west of the Rhone River and between two NNE-tren-ding deep faults. The elevation of its top is 1200m above sea-level. There are many Cenozoic pyroclastic volcanic layers and various NW-SE or N-S grabens in the massif. Also exist are a large number of NW tensile structures and a few NE compressive structures; or a few NW compressive structures and NE tensile structures in the Oligocene of the massif. They were formed respectively in the Pyrenessian type of S-N compressive stress field and the Alpesin E-W compressive stress field. The former played the dominant role during the Cenozoic. The activity of the massif was very strong at the southeast edge, with faults of great vertical displacement and different mechanical behavior and polyperiodic activity. The plateau has experienced intermittent upwarping as a result of successive intensive marginal faulting with the maximam upwarping occurring during and ofter the Middle Pleistocene.