The Himalayas were sunk after earthquake in Nepal, why? – Terra Colombia

The loss of height of the Himalayas of Nepal earthquake

A strip of the mountains of the Himalayas lost around one meter in height as a result of the devastating earthquake in Nepal, which occurred on April 25, according to scientists.

The loss of height will be balanced by a slight elevation of the plates as a result of tectonic activity, experts say.

Photo: BBCMundo.com

although they add that the loss thanks to a slight elevation of the plates due to tectonic activity was balanced.

They must still analyze satellite images of the region in which the most famous peak, Mount Everest is located.

But today still discussing how high that hill really.

“The height is lost mainly a strip of between 80 and 100 kilometers of Langtang Himal (northwest of the Nepalese capital Kathmandu),” said Richard Briggs, a research geologist United States Geological Survey (USGS, for its acronym in English).

Scientists have yet to analyze satellite images of the region in which the most famous peak, Mount Everest is located.

Photo: AP in Spanish

That is precisely one of the areas where locals and hikers are still missing, presumed dead, after avalanches and landslides caused by the earthquake of magnitude 7.8 on the Richter scale.

Doubts Everest

Scientists believe that a handful of peaks of the Himalaya mountain range might have missed height, including the Ganesh Himal in the west of Langtang stretch.

The satellite images analyzed by the experts are the center of the country, the area most affected by the quake.

And Everest is in the east of the area which trembled.

Experts say that if the highest peak in the world lost centimeters high or not will have to be confirmed by analysis of the soil, with a GPS or from an air mission.

“But from what we saw after evaluating the data is that beyond the plate boundary in northern the capital city of Kathmandu, you can clearly identify the region sank 1.5 meters, “says Christian Minet, a geologist at the German Aerospace Center (DLR), which processes the data sent by the earthquake Sentinel-1a satellite.

Images before and after

Scientists at the Center for Earth Observation DLR compared two images of the same region sent by the satellite, one before the earthquake and the other after.

“The positive values ​​that we receive (on the satellite image) after the earthquake mean that the area (the mountains of the Langtang region and vicinity) is farther from the satellite and is lower now, “Minet said.

“But this result can not say that a specific mountain is now a meter and a lower peak, is the general area that we can evaluate,” he adds.

According to the expert, satellite images showed a decrease in the height of the mountain range between 0.7 and 1, 5 meters.

The study also found that certain areas including the capital, Kathmandu, and the southern Himalayas rose because of the quake.

“and the negative values ​​received from the post-earthquake images mean that some areas (Kathmandu and surrounding areas) are now closer to the satellite, which means there was an elevation” says Minet.

Before this, scientists make clear that the elevations and depressions are normal geological behavior during an earthquake of this scale.

frontal collision

“The fault slipped under Kathmandu under the bark of the south, where flattened, and stretched toward the north end, “says Tim Wright, satellite geodesy professor at the University of Leeds, UK.

“In the flattened part, more or less below Kathmandu, we have the lift. And where is reached in the high mountains north of the capital, in this case, we have the sinking, “he adds.

“Most of the fault slip occurred just north of Kathmandu, so the mountains north of the capital are the ones that sank in this particular case.”

Normally the height of the Himalayas increases due to tectonic collision between India and Eurasia plates.

But during large earthquakes the process is reversed, experts say.

“Between earthquakes Nepal is being crushed and the nearest large part to the failure (including Kathmandu) carried by the Indian plate. And the most remote areas are rising (… ), “adds Wright.

“Now, during the earthquake that happened is the opposite,” he says. “The party was dragged down because he was trapped in the fault he slipped free and bounced up, and the party was being crushed sank”.

In this connection, the authorities in Nepal say they are yet to assess the impact of the earthquake in the Himalayas, as they are still busy with the rescue and rehabilitation.