A combined team of researchers from the University of Lausanne in Switzerland and Wageningen University in The Netherlands has found that a canyon in the eastern part of the Himalayas is moving slowly northward due to pressure from tectonic lift. Previously, scientists believed that erosion was the main driver of the migration. But turns out, it’s not. With a new mineral-dating technique called optically stimulated luminescence (OSL) thermochronometry, they were able to confirm that it was due to tectonic shifting.
According to researchers, their new technology can measure electrons that have been trapped inside a material such as quartz or feldspar, which in turn provides precise measurement of rock movements. Measuring the electrons trapped inside the rock, they can measure how recently the rock was moved to its current location and gather information about changes to the landscape due to tectonic shifting. Their new technology is able place the age of rocks to approximately 200,000 years ago.
For the study, researchers gathered samples from five different locations along an eastern part of the Himalayan region known as Namche Barwa. Prior study showed that increasing exhumation rates within the past million years at the northeast end of the Namche Barwa–Gyala Peri dome forced it to migrate towards north. Although both factors – propagation of erosion in the Parlung River and tectonic lift – contribute to changes in the landscape, results indicate that tectonic lift plays a far more important role in ‘topological deformation’ in the area.
- Source: Phys
- Reference: Northward migration of the eastern Himalayan syntaxis revealed by OSL thermochronometry – Science