Wabar craters
21.5025550.47408Koordinaten: 21 ° 30 '9 "N, 50 ° 28' 27" E
The Wabar crater (Arabic وابر, Wabar DMG ) are caused by a meteorite impact on the earth's surface visible impact crater in Saudi Arabia.
The discovery
The vast desert in the south of Saudi Arabia, also known as the Empty Quarter, or under the Arabic name Rub al Khali is one of the most desolate places on earth. In 1932, British researchers examined the Harry St. John " Abdullah " Philby, father of the spy Kim Philby, after the city of Ubar, of which the Quran is that it had been destroyed by God because the residents had opposed the Prophet Hud. Philby translated erroneously as Ubar Wabar. After the area roams a month, he was held in February 1932 a patch of ground, about half a square kilometer in size, the covered chunks white sandstone of black glass and pieces of iron meteorites war.Dort were two large pits, some of which were filled with sand. An analysis of the iron chunk was found that the piece of 90% was made of iron, the nickel content was 5 %, the remainder containing different elements, including copper and cobalt, and 0.0006 % (6 ppm) - an unusually high concentration - of iridium.
The location
The Wabar area covers an area of about 500 by 1,000 meters, the latest maps show three striking, almost circular crater; two of which have already been observed by Philby, one with a diameter of 116, the other of 64 meters, the third crater has a diameter of 11 meters and was discovered in the 1990s during the second Zahid expedition. All impact craters have a background of "instant rock ", which had been formed by the impact from the existing sand. Today, all three craters are almost completely filled with sand.
Was on the surface in part of the above-described " instant rock " or Impaktit similar to a sandstone, besides, she was covered with black floss and glass beads. The Impaktit had the form of coesite, a high-pressure modification of quartz. Since the impact was not penetrated to basement, but was held back from the sand, the Wabar area is very valuable for the research.
Also, the presence of iron fragments pointed to a meteorite impact, especially since there is no iron deposits in the area. The iron had the form of fist-sized balls broken and smooth weathered by sand fragments on the surface. The largest piece was salvaged in 1965, it has a mass of 2.2 tonnes. It is known as the " camel hump" and was exhibited at the King Saud University in Riyadh; today it is in the new National Museum of Saudi Arabia.
The appearance of the impact area suggests that the celestial body is wrapped in a shallow angle, but moves with the typical speed of 40.000 up to 60.000 km / hr. Its total weight was more than 3,500 tons. Due to the flat angle of the impact resistance was higher than that of air at a steeper angle. Apparently broke the meteorite before impact into four parts.
Dating
A Fission - track analysis of glass fragments revealed that the impact had to have occurred thousands of years ago, however, the fact that the craters were filled since their discovery by Philby considerably with sand, suggest that they are much younger. A thermoluminescence dating by Prescott et al. (2004) suggests that the impact area is not older than 260 years.