Lateral effect of Altyn fault strike-slip movement on Qaidam basin
The Altyn fault because of its huge size and strike-slip quantity,is considered by many scholars that has the significant lateral effect and the deformation mechanism of inverse S-fold-thrust belt in the northwest Qaidam basin is attributable to this,but this view lacks experimental basis.Physical simulation is the effective method for the study of tectonic deformation mechanism,the author through three groups of 3 dimensional model study of the range and the way in the Qaidam basin tectonic deformation influenced by the Altyn fault strike-slip,gets a result which shows that: ①The Altyn fault whether the strike-slip or the extruded strike-slip,has an extrusion effect on Qaidam basin,but the range of extrusion stress and the movement velocity of terrane are difference: The front edge of influence range of extrusion-type strike-slip is straight line with slow velocity decreasing,compared to arc of strike-slip and sharp velocity decreasing;②The deformation strength of near the north-south contraction in Qaidam basin far outweighs the deformation caused by the sinistral strike-slip of the Altyn fault,which changes the movement direction caused by the strike-slip traction of the terrane closed to the Altyn fault;③The influences of the Qaidam basin tectonic deformation by the Altyn fault strike-slip focus on the southwest of the basin,which is inconsistent to the area of inverse S-fold-thrust belt development and it negative to the view that the formation of inverse S-fold-thrust belt is controlled by the Altyn fault.