The formation mechanism of the Cona Woka rift in Eastern Himalaya and its influence on the Tethyan Himalayan polymetallic deposits revealed by magnetotelluric imaging

Magnetotelluric Imaging of the Central Himalayan Crust Away From Rift Zones

“…(2018) MT profiles. Although shallow conductive bodies can be generated by graphite films or sulfide minerals (Jones, 1993; Unsworth et al., 2005), the widely distributed conductive layer observed in the northern Himalayas tends to be caused by interconnected fluids or partial melts (Unsworth et al., 2005; Wang et al., 2023; Wei et al., 2001; Xie et al., 2016). According to the analysis of Chen et al.…”

“…The conductive layer CL in the upper crust of the northern Himalayas has also been found in other MT studies (Figures 5a and 5c), such as the INDEPTH Line-100 (Unsworth et al, 2005), and Liang et al (2018) MT profiles. Although shallow conductive bodies can be generated by graphite films or sulfide minerals (Jones, 1993;Unsworth et al, 2005), the widely distributed conductive layer observed in the northern Himalayas tends to be caused by interconnected fluids or partial melts (Unsworth et al, 2005;Wang et al, 2023;Wei et al, 2001;Xie et al, 2016). According to the analysis of Chen et al (2018), the temperature is below 600°C for the conductors shallower than 10 km; therefore, the cause of is likely mainly saline fluids.…”

“…The magnetotellurics data were obtained by the Institute of Geophysical and Geochemical Exploration, Chinese Academy of Geological Sciences. The MT data file (Wang, 2023) for this study can be found online with open access (https://doi.org/10.5281/zenodo.8146389). The matlab code to handle and display the data set can be found at https://github.com/dong-hao/EM3DVP.…”

“…The last important extensional structures in southern Tibet are the north–south trending rifts, which were caused by the east–west extension during the period 23–3 Ma (Bian et al., 2020, 2022; Yin & Harrison, 2000; Zhang et al., 2012). These southern Tibetan rifts are also closely related to the distribution of the Gangdese metallogenic belt (GMB) (Hou et al., 2004, 2015; Tang et al., 2014; Wang et al., 2022) and Tethyan Himalayan polymetallic belt (Guo et al., 2019; Wang et al., 2023). In southern Tibet, the Dingjie‐Shenzha and Yadong‐Gulu rifts are the two largest rifts that cut through the Yarlung‐Zangbo Suture, Southern Tibet Detachment System, and North Himalayan Gneiss Domes from north to south.…”

“…The receiver‐function profile parallel to the HOB showed that the 20‐km‐thick Indian lower crust that underplated Tibet at 88.5–92°E beneath the Yarlung‐Zangbo suture is essentially absent near the Cuona‐Woka (92°E) and Dingjie‐Shenzha (88°E) rifts. Furthermore, MT profiles along the east‐west direction have found large‐scale electrically conductive anomalies underneath the Cuona‐Woka (Wang et al., 2023), Yadong‐Gulu (Wang et al., 2017), and Dingjie‐Shenzha (Sheng et al., 2021) rifts, respectively. Late formed rifts in southern Tibet may have overprinted the HOB dynamics that occurred at an earlier stage; hence, the obtained geophysical results may not be representative of the previous structure and state of the HOB.…”