A stretch of the mountain range of the Himalayas lost about one meter in height as a result of the devastating earthquake in Nepal, which occurred on April 25, according to scientic.
Although added that the loss due to a slight rise due to plate tectonic activity was balanced.
They must still analyze satellite images of the region where is the best known summit Everest.
However, 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 at the US Geological Survey (USGS, for its acronym in English).
Scientists have yet to analyze satellite images of the region where the summit is known, Everest.
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.
QUESTIONS WITH EVEREST
Scientists believe that a handful of peaks Himalaya mountain range might have lost height, including the Ganesh Himal in the west of Langtang section.
The satellite images analyzed by the experts are the center of the country, the area most affected by the earthquake.
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 the north of the capital Kathmandu, you can clearly identify the region sank 1.5 meters, “says Christian Minet, a geologist at the German Aerospace Center (DLR), which Earthquake processes data sent by the satellite Sentinel-1a.
IMAGES BEFORE AND AFTER
Scientists at the Center for Earth Observation DLR comparing two images of the same region sent by the satellite, one before the earthquake and the other for later.
” Positive values received (on the satellite image) after the earthquake mean that the area (the mountains of the Langtang region and vicinity) is farther from the TV and it’s lower now, “Minet said.
“But with this result we can not say that a particular mountain is now a meter and peak lower; 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 increase,” says Minet.
Before this, scientists make clear that the elevations and depressions are normal geological behavior during an earthquake of this scale.
Collision
“The fault slipped under Kathmandu under the bark of the south, where it was crushed, and stretched toward the north end” says Tim Wright, professor of satellite geodesy at the University of Leeds in the UK.
“In the flattened part, more or less below Kathmandu, we lift . And where is reached in the high mountains north of the capital, in this case, we are 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. “
The authorities in Nepal say it is still assessing the impact of the earthquake in the Himalayas, as they are still busy with the rescue and rehabilitation.
Normally the height of the Himalayas increases due to the colisió between the tectonic plates of India and Eurasia.
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 (…) “added Wright.
” Now, during the earthquake that happened is the opposite, “he says.” The part that was pulled down because it was trapped in the fault slipped free and bounced up, and the party was being crushed sank. “
In this connection, Nepalese officials say they are still evaluating the impact of the earthquake in the Himalayas, as they are still busy with the rescue and rehabilitation.
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