Kebira Crater

Kebira Crater (Arabic: فوهة كبيرة) is the name given to a circular topographic feature that was identified in 2007 by Farouk El-Baz and Eman Ghoneim using satellite imagery, Radarsat-1, and Shuttle Radar Topography Mission (SRTM) data in the Sahara desert.

Based solely on their interpretations of the remote sensing data, they argue that this feature is an exceptionally large, double-ringed, extraterrestrial impact crater.

[10] After the existence of a possible impact structure was announced, in early March 2006 an expedition traveled through the site and informally published their findings: "[C]ontinued north .

The circular shape appears to be pure coincidence, the whole feature is the result of drainage patterns and subsequent eolian erosion, there is nothing to suggest its impact origin."

After analyzing the presence/absence of several geologic features associated with impact craters, such as target rocks, breccias, pseudo-shatter cones, and circular morphology, the authors concluded: "[T]here are [sic] no clear and unequivocal evidence supporting the impact origin of the circular structures in Glif Kebir region; until substantial evidence is produced, it's necessary to identify the origin of the craters in others [sic] endogenic geological processes."

They proposed the most likely alternative source of the crater to be a hydrothermal vent, although they went on to say: "However, even this hypothesis is not fully satisfactory: probably these complex and peculiar features are the result of interaction between different geological process.

Anyway, the lacking of clear evidences of a meteoritic impact and the geological framework of the investigated area, lead us to confirm the hydrothermal-volcanic hypothesis.

Instead of proposing that Libyan desert glass was ejected from this feature by an impact, they hypothesized that it was transported from it by an Oligocene-Miocene Gilf River system that contained the Kebira Crater within its drainage basin.

[12] Most recently, Longinelli and others studied the oxygen isotope and chemical composition of Libyan desert glass and samples of sands and sandstone from its proposed source areas.