Tehran, the capital of Iran, was found hit by a large ground subsidence and found to be unpredictable

By Gilbert Sopakuwa

In Tehran, the capital city of Iran where about 15 million people live, it has been found by investigation using artificial satellites that ground subsidence that the height of the ground lowers in the center of the city and plain areas in the suburbs.

Tehran's drastic sinking exposed by satellite data
https://www.nature.com/articles/d41586-018-07580-x

Tehran's drastic sinking exposed
(PDF) https://www.nature.com/magazine-assets/d41586-018-07580-x/d41586-018-07580-x.pdf

Tehran Is Sinking Dramatically, And It May Be Too Late to Recover
https://www.livescience.com/64235-tehran-is-sinking.html

According to the data measured from the artificial satellite, the ground level of the whole town is said to have sudden ground subsidence occurring in Tehran as much as 10% of the area, and its value reaches as much as 25 cm per year Thing. In the map below, the place with the most subsidence is shown in red color.

This survey was conducted by a team of geologists Mahdi Motagh and Mahmud Haghshenas Haghighi of the German Earth Science Research Center (GFZ) of the German Research Center Helmholtz Institute . Based on the satellite data from 2003 to 2017, we investigated the situation of the ground subsidence throughout the city.

In Tehran recently, sudden changes such as "Sink Hole" suddenly opening hole on the ground and sudden rupture of huge ground appear frequently. The two researchers have proceeded to investigate their present condition and cause.

It turned out that the greatest cause of ground subsidence is still "reduction of groundwater" to say. Drought occurred due to less rain, furthermore the dam was built upstream of the river, the supply of water decreased, and the groundwater level suddenly dropped due to the excavation of an illegal well, one after another the ground There is a situation in which it sinks.

To make matters worse, I heard that this phenomenon has already reached a level that can not be reversed. The Tehran authorities have taken measures such as reducing the number of wells where there were 100,000 bottles to 30,000, but the supply of groundwater itself was lost due to the decrease in precipitation and so on, Returning is a tough situation. As the settlement continues, the risk of seriously affecting gas pipes, water pipes, railroads, roads and pier will continue to increase.