NASA Earth Observatory images by Lauren Dauphin, using Landsat data from the U.S. “The two effects together mean that the lake will disappear over time.” Also, sediments that have eroded from the hills and channels are filling the lake. “This is the best-case scenario for this type of situation, releasing the water slowly and progressively with time,” Petley said. In the vicinity of this particular lake, erosion of the earthen dam is slowly lowering the lake level. The whole way that the environment is operating has changed.” It is not just that buildings and infrastructure are damaged. “This is the frequently forgotten effect of an earthquake. The epicentre was about 82 kms (50.95 miles) from the nearest border with China and the earthquake was. “The people have to deal with these effects, and they are profound and dangerous,” Petley said. Tajik authorities said there was no sign of the lake being disturbed by the earthquake. And huge amounts of sediment were mobilized. It is located in the Naval Air Weapons Station China Lake. You can see it for yourself by entering the coordinates into Google Maps in Satellite mode. The earthquake caused the kinds of changes to slopes and channels that can last for years or decades, according to Dave Petley of the University of Sheffield. For those who haven’t seen this image, it’s at China Lake near the epicenter of the California 7.1 earthquake. These images were acquired before the start of the rainy season, so the image sequence likely represents the longer-term effects of an earthquake on the landscape. Water levels can fluctuate over the course of a year, especially after large rainfall events. The second image shows the same area on April 2, 2018, after water levels have lowered. The first image shows the lake on April 28, 2016, when water levels were still relatively high. The change is visible in this image pair, acquired with the Operational Land Imager (OLI) on Landsat 8. Ten years later, the lake’s water level has dropped. The earthen dams caused water levels to rise and spawned more than 20 “quake lakes.” A series of satellite images published in 2008 showed the growth of one such lake in Beichuan County, one of the most severely affected quake regions. The quake triggered deadly landslides, some of which blocked the flow of rivers. On that day, a magnitude 7.9 temblor-known as the Great Sichuan or Wenchuan earthquake-caused destruction to areas near and far from the epicenter, about 80 kilometers west-northwest of Chengdu. Downstream from the lake, residents were evacuated overnight as. 45 days after the quake, at 7pm on October 9, 1933, powerful aftershocks burst the barrier lake. The water in the lake stretched back more than 12 kilometers, and at its widest point it was two kilometers across. More than half of Chinas counties have mountainous areas. The quake injured nearly 362,000 people and new aftershocks toppled 420,000 houses, many already uninhabitable, on Tuesday. Eleven days after the earthquake a lake had appeared high up in the gorge. On May 12, 2008, the mountainous landscape of south-central China was profoundly changed. Hills, mountains and plateaus cover two-third of the population.
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