Post-collisional, Potassic and Ultrapotassic Magmatism of the Northern Tibetan Plateau: Constraints on Characteristics of the Mantle Source, Geodynamic Setting and Uplift Mechanisms

Speculations on the formation of cratons and cratonic basins

“…Tainton and M c Kenzie (1994) used the trace element composition of kimberlites and other alkaline rocks, especially the concentrations of the rare earth elements, to show that their source regions had been strongly depleted by basalt removal. The same approach has been used to estimate the density contrast resulting from composition alone between the source regions of the alkaline rocks and the convecting upper mantle (see Supplementary Material), using melt compositions whose MgO concentration is 6% or more, taken from Allen et al (2013), Gibson (personal communication), Nomade et al (2004), Williams et al (2004) and Guo et al (2006). The resulting values in Fig.…”

“…The approach outlined by Tainton and M c Kenzie was used to model the composition of the potassic melts reported by Nomade et al (2004), Gibson (personal communication), and Guo et al (2006). The locations of the samples are shown in Fig.…”

Petrogenesis of the Early Eocene adakitic rocks in the Napuri area, southern Lhasa: Partial melting of thickened lower crust during slab break-off and implications for crustal thickening in southern Tibet

“…The zircon U-Pb isotopic data are given in Gangdese Batholith (Chung et al, 2003;Gao et al, 2007Gao et al, , 2010Guan et al, 2010Guan et al, , 2012Guo et al, 2006Guo et al, , 2007Hou et al, 2004;Ji et al, 2012;Jiang et al, 2012;Ma et al, 2013a;Wen et al, 2008b;Xu et al, 2010;Zhang et al, 2010a,b;Zhu et al, 2009) ~100-150 μm with length-to-width ratios of 2:1 to 3:1 (Fig. 3).…”

Cenozoic Mg-rich potassic rocks in the Tibetan Plateau: Geochemical variations, heterogeneity of subcontinental lithospheric mantle and tectonic implications

“…India-Asia collision and the resultant Tibetan Plateau provide an outstanding natural laboratory for studying continental orogenic processes, attracting many workers (e.g., Coulon et al, 1986;Turner et al, 1993;Zhao and Nelson, 1993;Coleman and Hodges, 1995;Nelson et al, 1996;Kosarev et al, 1999;Yin and Harrison, 2000;Tapponnier et al, 2001;Blisniuk et al, 2001;Haines et al, 2003;Nomade et al, 2004;Unsworth et al, 2005;Chung et al, 2005Chung et al, , 2009Guo et al, 2006;Klemperer, 2006;Mo et al, 2007Mo et al, , 2008Zhao et al, 2009a;Wang et al, 2010;Zhang et al, 2010). However, the processes responsible for the Cenozoic elevation history of the Tibetan Platean are not well understood.…”

“…The Cenozoic volcanic rocks that are widely distributed on the Tibetan Plateau can significantly contribute to our understanding of uplift mechanisms, and the formation and development of the plateau. Previous research that focused on Cenozoic potassic volcanics has already enhanced our understanding of the processes that operated during India-Asia collision, such as multi-episodic magmatism and various hypotheses that explain the evolution of the Tibetan Plateau during the Cenozoic (e.g., Coulon et al, 1986;Turner et al, 1993Turner et al, , 1996Miller et al, 1999;Tapponnier et al, 2001;Hou et al, 2004;Nomade et al, 2004;Chung et al, 2005Chung et al, , 2009Guo et al, 2006;Gao et al, 2007a;Mo et al, 2007Mo et al, , 2008Zhao et al, 2009a). Nevertheless, the petrogenesis of these Cenozoic magmatic rocks and geodynamic setting remain controversial.…”