Seznam sopek v Africe

Vlajka Jihoafrické republiky

Used color: National flag | South African Government and Pantone Color Picker

• The Tibesti Mountains in northwestern Chad consist of rugged volcanic peaks, many impressive craters, and hot springs. Near the center of the photograph is Tousside Peak, which rises more than 10 710 feet (3265 meters) above sea level, the westernmost volcano of this high mountain range. The peak is almost centered within the black shape that has tentacle-shaped lava flows extending down the western flank. The volcano’s base measures approximately 55 miles (90 kilometers) in diameter. The light brownish area surrounding the peak shows a distinctive radial drainage pattern that is quite common for stratovolcanoes as the terrain falls away from the main peak. The depression southeast of the volcano measures approximately 5 miles (8 kilometers) in diameter and 3300 feet (1000 meters) in depth. The white base is caused by an accumulation of carbonate salts, creating this soda lake of Tibesti. With the exception of small vents that emit gasses and a few hot springs that continue to deposit minerals at the surface of the crater floor, little volcanic activity presently occurs in this region.
  Image number STS052-73-14

Original NASA caption, for a version similarly cropped to show just Marion Island:

"A dusting of ice graced the summit of Marion Island in early May 2009 as waves breaking against the island’s shore formed a broken perimeter of white. Like its smaller neighbor, Prince Edward Island, Marion Island is volcanic, rising above the waves of the Indian Ocean off the southern coast of Africa. Prince Edward and Marion are part of South Africa’s Western Cape Province. (Both islands appear in the large image.)

"The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite acquired this natural-color image on May 5, 2009. Sunlight illuminates the northern slopes of the volcanic island, leaving southern slopes in shadow. More than 100 small, reddish volcanic cones dot the island, some of the most conspicuous in the north and east. The island reaches its highest elevation, 1,230 meters (4,040 feet), near the center. Vegetation is generally sparse on Marion Island. Lichens live near the summit, and mosses and ferns grow elsewhere on the boggy surface, but trees don’t grow on the island.

"Occurring at the juncture between the African Continental Plate and the Antarctic Plate, Marion Island has been volcanically active for 18,000 years. The first historical eruption was recorded in November 1980 when researchers recorded two new volcanic hills and three lava flows. Researchers observed another small eruption in 2004.

• This spectacular range of basaltic cinder cones and associated lava flows covers a 55 x 90 km area, and flows reached the Red Sea along a broad front.
• The vents of the Assab volcanic field were constructed along a broad E-W-trending line that extends to the coastal city of Assab, out of view to right.

The image is averaged from 58 Landsat 8-scenes, provided by NASA. Bands 4, 3, 2 and 8 were combined into an RGB image. Panchromatic sharpening, conversion to radiance, weighted averaging, and rescaling to extrema of the scenes was done in R with the package RStoolbox. JPEG-encoded with Guetzli.

Images acquired in the range 18. července 2013 – 2. března 2021, each at mean 10:05, range 10:04–10:07. The sun position range: azimuth 86°–155°, average 133°; elevation 38°–69°, average 52°.

Resolution: 15m.

Projection: UTM 31 N, WGS84.

Center: 769590, 2574870.

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