Kinematics of the Greater Himalayan sequence, Dhaulagiri Himal ...

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during Eohimalayan deformation and initial imbrication of the supracrustal northern margin of
India (Godin, et al. 1999a), as a result of shear related to top-to-the-north sense Neohimalayan
displacement across the STDS (Burchfiel et al. 1992), or due to reorientation during partial
coupling with a southward extruding viscous mid-crust (Kellett et al. in review). These folds are
transposed at lower structural levels by a moderately north-dipping pervasive foliation related to
motion along the STDS (Godin et al. 1999b).
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3.2 South Tibetan detachment system
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The STDS, locally comprising the Annapurna detachment (Kali Gandaki valley; Brown
& Nazarchuk 1993; Godin et al. 1999a), the Deurali and Macchapuchhare detachments (Modi
valley; Hodges et al. 1996;), and the Chame and Phu detachments (Nar valley; Coleman 1996;
Searle & Godin 2003; Gleeson & Godin 2006; Godin et al. 2006b) in central Nepal, crops out in
the Daulagiri Himal as a plastic-brittle normal-sense fault that juxtaposes the Tethyan
sedimentary sequence in its hanging wall against the Greater Himalayan sequence in its footwall
(Brown & Nazarchuk 1993; Godin et al. 1999b). The STDS is a 1500 m thick high-strain zone
that predominantly affects the upper greenschist facies Larjung Formation (Figure 2), but also
extends structurally downwards in the Greater Himalayan sequence and structurally upwards into
the lowermost Tethyan rocks (Godin et al. 1999b; Godin 2003). The lower boundary of the
STDS, comprising the Chame, Annapura, Deurali detachments, was active in central Nepal prior
to ~22 Ma (Guillot et al. 1994; Harrison et al. 1995; Hodges et al. 1996; Godin et al., 2001),
coincident with motion along the MCT (Godin et al. 2006a). Displacement across the upper
boundary of the STDS, the Macchapuchhare and Phu detachments, ceased in central Nepal by
~16 Ma (Godin et al. 2006b).
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