The tsunami that struck Sulawesi Island Indonesia caused by an earthquake late September has brought into being an ongoing slow-motion natural disaster. Hundreds of thousands of people have been affected. The floodwater from the tsunami has receded but the destruction rages on. Some unbelievable imagery has been captured through surveillance from outer space that presents the drastic situation of the country’s land, literally, liquefying!
Earthquake-prone areas without a solid bedrock foundation are susceptible to liquefaction, especially if the soil is saturated, be that by rain or high water table. Furthermore, the shaking of an earthquake can increase water pressure in the soil and cause loose, sandy soil to become semi-fluid, like lava.
When the earthquake struck, it loosened the soil beneath the coastal city of Palu. This lead to landslides that began melting the city away. The ground has completely liquefied. Horrifying imagery caught by satellite’s hovering above the Earth was sent back to a team on the ground working on recovery efforts.
Among the most shocking scenes was one shared by Sutopo Purwo Nugroho, a member of Indonesian National Board for Disaster Management. The scene was composed of data from Digital Globe’s Worldview blends before and after (current) imagery to show how an entire chunk of countryside near Palu liquefied and slid downslope.
Video surveillance on land shows another perspective of liquefaction and some of it is quite bizarre! At the human-scale, the imagery consists of houses collapsing and even full buildings gliding by, riding the fluid soil like how an ice-cube would slide along a smooth surface.
On news regarding the locality’s current situation, a countless number of people have lost their homes and the death toll has risen to 1,763 people with around 5,000 still missing within the rubble. Search and rescue efforts are being done primarily by hand since heavy machinery has yet to reach the area. A large mass grave (10 meters by 100 meters) for the burial of bodies is being dug that can hold 300 victims and can be enlarged if needed. This is but a temporary measure necessary to stop the spread of disease. To top it off, the structural damage to prisons has allowed for a massive prison break with 1,425 prisoners now missing from jails across the area. Indonesia has confirmed it will accept international assistance for the disaster putting out calls for help. So far, Australia and Thailand have offered support.