title of the thesis - Department of Geology - Queen's University

1996; Godin et al., 2001; Harris et al., 2004). Motion along the STDS terminated by ~16 Ma in
central and eastern Nepal (Godin et al., 2006b; Cottle et al., 2009a,b), implying that extrusion of
the GHS had also ceased.
2.3.1.2 Orogen-parallel extension
Orogen-parallel extension has been active from middle Miocene up to present day
throughout the Himalaya and Tibetan plateau (see Fig.2.2 from Styron et al., 2011 for
comprehensive review). Extensional deformation is commonly manifested throughout Tibet as
east-west to ESE-WNW oriented strike-slip faults and north-striking rifts (Fig. 2.2a; Armijo et al.,
1986, 1989; Taylor et al., 2003; Taylor and Yin, 2009). The majority of these structures are
located within central to southern Tibet and restricted to the upper crust (Armijo et al., 1986,
1989; Taylor et al., 2003; Taylor and Yin, 2009). Within the Himalaya, extensional deformation
is expressed as orogen-perpendicular normal faults, orogen-parallel strike-slip faults, and
migmatite-cored gneiss domes (Fig 2.2a; Nakata, 1989; Murphy et al., 2002; 2009; Murphy and
Copeland, 2005; Thiede et al., 2006; Jessup et al., 2008; Li and Yin, 2008; Jessup and Cottle,
2010). Three Himalayan gneiss domes (Leo Pargil, Gurla Mandhata, and Ama Drime – Fig.
2.2a,b) exhume rocks of upper amphibolite to granulite metamorphic facies in settings
kinematically linked to orogen-parallel extension (Murphy et al, 2002, 2009; Thiede et al., 2006;
Jessup and Cottle, 2010). Structures related to orogen-parallel extension initiated between ~ 16 -
11 Ma (Fig 2.2; see Fig. 2 from Styron et al., 2011 for a comprehensive age review).
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