Relationship Between the Movement of Ordos and Tarim Blocks and Strong Continental Earthquakes

Abstract eng:
On the basis of comprehensive analyses of geology, paleomagnet, GPS data and seismicity, the relationship between the movement of Ordos and Tarim blocks and strong continental earthquakes is discussed. Both Ordos and Tarim blocks are the old intact solid block with simple inner structures, and fault depression zones or orogens around the two blocks are fractural and the inner structures are complex. Whole translational movement to the east and anticlockwise rotation of the Ordos block control the strike-slip fault and earthquake occurrence around the Ordos block, and the movement to the north, clockwise rotation and underthrusting of the Tarim block under orogens result in faulting and earthquake occurrence around the Tarim block. For example, the M≧6 earthquakes in the border of the Tarim block and Tianshan orogens are possibly affected mainly by the motion of the Tarim block although Tianshan is a well-known seismic zone. The traditional stable block like Ordos and Tarim blocks is truly the intact solid active block, which is the main contributor to strong earthquakes on the border. It is difficult for strong earthquakes to occur within tectonic active zones such as fault depression zones and orogens around the integrated solid block because it is not easy for these zones to accumulate big stress due to strong fracture and deformation. It is pointed out that the whole motion of the intact solid block like Ordos and Tarim blocks plays a crucial role in strong earthquake occurrence around its border.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket