Mexico comes to its senses after the recent devastating earthquake, and a strange phenomenon has been seen on its streets. The video shows a piece of asphalt covering, rising and falling in front of the amazed audience, like a large animal breathes somewhere near Mexico City. Local resident Rigoberto Lechuga Silva drew attention to this phenomenon on September 19, when the tremors trembled the neighborhood.
Silva, like many others, rushed to the street, trying to move away from the staggering buildings. He saw a swaying lamppost and took out his phone to write it down, when suddenly noticed the ascending and descending asphalt.
— Preston Phillips (@PrestonTVNews) 21 сентября 2017 г.
After the man posted his video on the Internet, it quickly spread over various resources.
On the pages of “Twitter” scientists who watched the movie, began to offer theory about the source of this movement. Geophysicist Mika McKinnon suggested that liquefaction might be behind this phenomenon. In her message, she noted that Mexico was built in a sedimentary basin, so it is not surprising that unusual geological events follow intense seismic activity.
Hundreds of years ago in Mexico City there was much more watery terrain. In the XIV century, on the island, located in the heart of a marshy landscape, the Aztec city Tenochtitlan was built. While the territory was later drained by the Spaniards, the loose sediment that once supported these waterways is now locked up under the eleventh most populous city in the world. Most of this loose sediment is still saturated with water or interrupted by air pockets.
When seismic waves, for example from an earthquake, pass through an area, sedimentary particles can then oscillate as a liquid in a process known as liquefaction. After watching the video, Susan Hugh, a USGS seismologist, said that liquefaction is a likely explanation for the asphalt rise: “During major earthquakes, you can get sandy soils rising to the surface in the form of impulses. The thing here is that we have a pavement above the ground. ” She added that an exact reason will be established as soon as the Mexican authorities can inspect the land under the road.
Mexico is not the only place where you can see how roads are liquefied after a major seismic event. Video from Japan, taken after the earthquake in 2011, shows a crack on the sidewalk, which opens and closes.
Согласно отчету USGS, большие части Сан-Франциско очень восприимчивы к сжижению. Сжижение часто усугубляет ущерб от землетрясений, ослабляя почву, на которой строятся высокие городские структуры. В худшем случае оно может вызвать оползни и разрушения.