G) Paleomagnetism:

        In eastern Tibet, paleomagnetic data indicate high amounts of clockwise rotation in the eastern Himalayan syntaxis which is consistent with right-lateral simple shear and associated oroclinal bending. For creation of this deformation pattern, some authors have suggested kinematic models implying NE extrusion of Tibetan plateau. However, paleomagnetic data obtained from Tertiary red sedimentary rocks of Tarim and Qiadam basins show no significant Neogene vertical-axis rotation in northern Tibet (Dupont-Nivet et al. 2002)(figure 20). These results contradicts with extrusion models implying clockwise rotation of Qiadam basin at rates approaching 1 degree / m.y. This difference in vertical-axis rotations may result from highly localized active shearing along Altyn-Tagh and Kunlun faults and from contrasting lithospheric properties between Qiadam, Tarim basins (strong) and northern Tibet (weak). It is worth noting that these data are coming from Guillaume Dupont-Nivet's Ph.D. work and he has still lots of things waiting to be published.
 

Figure 20.  Paleomagnetic declinations measured along northern and eastern
Tibetan plateau [Dupont-Nivet et al. 2002].
 
 
 

 

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A) Tectonics & Geology

B) Seismicity

C) GPS

D) Seismic profiles & Tomography

E) Gravity

F) Anisotropy

G) Paleomagnetism

H) Geochemistry

I) MT studies

 

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Introduction

Paleotectonic Evolution

Recent Deformation

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References

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