14 DAY TRIAL // A satellite image released by NASA scientists earlier this week shows the remains of a billion-year-old collapsed volcano towering over landscapes in South Africa's Pilanesberg National Park.
The view, obtained this past June towards the end of the month, was delivered by the space agency's Landsat 8 satellite, launched into Earth's orbit a couple of years back, in February 2013.
The volcano's remains are a collection of concentric circles
When collapsing, this volcano that huffed and puffed in South Africa a billion years ago left behind a collection of concentric circles made up of valleys criss-crossed by rocky hills.
“Seen from above, the concentric rings of hills and valleys make a near perfect circle, with different rings composed of different types of igneous rock,” NASA researchers explain.
The odd terrain is now known as the Pilanesberg caldera. Of the structures that comprise it, some rise an impressive 1,640 feet (roughly 500 meters) over their surroundings. Others are merely 330 feet (100 meters) tall.
As for the Pilanesberg caldera's tallest point, it goes by the name the Matlhorwe Peak and geologists say it stands 5,118 feet (approximately 1,560 meters) above sea level.
The volcano that created this arrangement of hills and valleys in South Africa is believed to have been active for about one million years before the movement of continental plates left it without its hotspot, shutting it down.
Lakes and streams sometimes emerge in the Pilanesberg caldera
The Landsat 8 satellite imaged the Pilanesberg caldera during the dry season and so the terrain appears barren in this view. However, researchers say the area is not always so arid.
During the wet season, i.e. between October and April, many streams form and flow nestled between the caldera's rocky hills and valleys. Mind you, people living in the area have even engineered dams to create watering holes for their animals.
