Although added that the loss due to a slight rise due to plate tectonic activity was balanced.
In addition, still need to analyze satellite images of the region where the summit is more known Everest.
However, today still discussing how high that hill really.
“The height is lost mainly a strip of between 80 and 100 Langtang Himal kilometers (northwest of the Nepalese capital Kathmandu), “said Richard Briggs, a research geologist at the US Geological Survey (USGS, for its acronym in English).
That is precisely one regions 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 Himalayas could 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 the Everest is in the east of the area which trembled.
The experts say 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 beyond the limit of the plate, 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 processes Earthquake data sent by the satellite Sentinel-1a.
Images before and after
The scientists of the Center for Earth Observation DLR compared two images of the same region sent by the satellite, one before the earthquake and the other later.
“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 TV and it’s lower now, “explains Minet
.” But with this result we can not assert that specific mountain is now a meter and 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 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 behavior Normal geological 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 in the 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 are sinking, “he adds.
” Most of the fault slip occurred just north of Kathmandu, by what the mountains north of the capital are most sank in this particular case. “
Normally the height of the Himalayas increases due to plate tectonics colisió between India and Eurasia.
But during large earthquakes the process is reversed, experts say.
“Between earthquakes Nepal is being crushed and the nearest part to the great failure (including Kathmandu) carried by the plate india. And the most remote areas are rising (…) “added Wright.
” Now, during the earthquake that happened is the opposite, “he says.” The party was dragged down because was trapped in the fault 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 still are busy with the rescue and rehabilitation.
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