ON THE CHARACTERISTICS OF NEOTECTONIC ACTIVITIES IN BAIKAL RIFT SYSTEM

The history of faulting of the Baikal rift system is esentially coincident with the associated sedimentary processes.The evolution of the rift system can be broadly divided into two stages:Primary stage ranging in age from middle-late Eocene to early Pliocene (E₂^2-3-N₂¹)and main stage from middle late pliocene to Quaternary(N₂^2-3-Q). The former is characterized by plastic deformation with no significant relief and weak fault activity, while the latter by brittle deformation with sharp relief and strong fault activity.
The Baikal depression is the earlist and the largest undewater depression of the Baikal rift system, where occurred notable neotectonic activities with an vertical movement from southwest to north-east.There are indications of a broadtilting from the west to the east in the area and the surrouding block mountains and basins.There have occurred bending and doming of a large number of planation surfaces and alluvialpluvial fans.The combination of different trend and mechanical properties suggests a NE-SW compression.