SHRIMP U–Pb in zircon geochronology of the Chor granitoid: evidence for Neoproterozoic magmatism in the Lesser Himalayan granite belt of NW India

Exact timing of granulite metamorphism in the Namche-Barwa, eastern Himalayan syntaxis: new constrains from SIMS U–Pb zircon age

“…U-(Th)-Pb ion microprobe analyses show that the inherited core of the HP granulite from the eastern Himalaya gives an apparent 206 Pb/ 238 U age of 1,806 Ma, which is in accord with the ages of detrital zircons from the Lower Himalayan sequence (e.g., DeCelles et al 2000;Singh et al 2002;Martin et al 2005) Int J Earth Sci (Geol Rundsch) (2012) 101: 239-252 247 and implying that the these rocks has an affinity with the Lower Himalaya sequence. The features described here from mineralogy, geochemistry, and 206 Pb/ 238 U zircon dating show that inner zonal zircons within the HP granulites preserve an oscillatory zoning pattern and have relatively high Th/U ratios, indicating that these inherited detrital zircons are of magmatic origin.…”

Position of South China in configuration of Neoproterozoic supercontinent

“…Bimodal magmatic rocks of middle Neoproterozoic ages occur in Madagascar of Africa [27 30] and India [31,32] . Granitoid having SHRIMP U-Pb age of 823 5Ma is also identified in the Lesser Himalayan granite belt in NW India [33] . It appears that the bimodal magmatic rocks in Seychelles, Madagascar and India can be compared with those in the northern margin of the South China Block with respect to both mid-Neoproterozoic ages and low 18 O values.…”

Tectonic interleaving along the Main Central Thrust, Sikkim Himalaya

“…These orthogneiss ages are consistent with similar meta-igneous intrusion ages from the Greater Himalayan Sequence elsewhere in the Himalaya. These include an event at c. 500 Ma (Bhargava 1995;Marquer et al 2000;Miller et al 2001;Ghosh et al 2005;Richards et al 2005) and an earlier Neoproterozoic event at c. 800 Ma (DiPietro & Isachsen 2001;Singh et al 2002;Ghosh et al 2005;Richards et al 2006;Spencer et al 2012). A widespread Cambro-Ordovician tectonic event has been documented across the Greater Himalayan Sequence (Argles et al 1999;Marquer et al 2000;Gehrels et al 2003Gehrels et al , 2006.…”