Notably, two historical poems written by separate authors have been found that describe the fall of a fireball over Tarim, Yemen, a town located 620 km south-southwest of the Wabar site (H. While there is some testimony that the fall could be associated with a witnessed event that occurred in 1863, current evidence suggests an earlier fall. From measurements of the rate of infilling of the craters by sand, as well as through TL studies, it is estimated that the fall occurred between 235 and 416 years ago, or an average of 289 (±46) years ago. The impactite distribution pattern indicated to the early investigators that the object arrived from the northwest at a shallow angle. It is estimated that the original mass weighed at least 3,500 tons and that the largest impacting fragment was ~9 m in diameter. (2013) ascertained that the pearls contain the largest component of projectile material, which lowered the melting point and the viscosity of the melt allowing for complete degassing as attested by their lack of vesicles. These pearls are composed of 90% local quartz sand and 10% microscopic particles of meteoritic FeNi-metal. This is consistent with the prevailing wind conditions during the early evening hours in early Spring. Black glass pearls like the one pictured on this page were found about a half-mile northwest of the crater, indicating that a wind was blowing from the southeast at the time of the fall. Wabar is a member of the IIIAB group of irons, a group considered to be closely related to group IIIE (Bishop et al., 2012), and exhibits a medium Thomson (Widmanstätten) structure (Buchwald, 1975). (2013) to conclude that the meteoroid arrived from the south. Examination of the distribution of the craters and the individual regmaglypted fragments led Gnos et al. Additional meteorite remnants uncovered below the sand have been completely weathered to shale. Other surface recoveries include a 210 kg mass and several other multi-kg masses, as well as numerous small, twisted fragments like the 14.1 g specimen pictured above. The largest known mass, which was finally collected in 1965 400 m south-southwest of the largest crater, is a shield-shaped, aerodynamically-oriented, 2,040 kg mass known as the "Camel's Hump". A third immiscible component consists of µm-scale metallic FeNi-spherules (up to sub-mm scale) representing projectile remnants. (2013) reveal that the black impactite is composed of a quenched, vesicular, glassy mixture of two immiscible liquids i.e., an emulsion of one phase enriched in Fe +2 and Ca +2 (derived from the FeNi-metal of the projectile) appearing as nmµm-scale spherules, within a dominant phase enriched in silica (derived from the 20≣0-m-deep target sands). Results of petrography and microchemistry conducted by Hamann et al. Map of the Wabar site (from the book: The Empty Quarter by Philby, 1933)įound dispersed in and around the craters was shock-bleached/-lithified sand, both black and white-greenish, aerodynamically-shaped, vesicular glass bombs (some containing highly shocked silicate phases such as lechatelierite, coesite, and stishovite), black melt droplets referred to as "pearls", and remnants of FeNi-metal spalled from the impacting body (Gnos et al., 2013). The three impact craters are situated on 125 acres of a constantly shifting dune field. The impact site consists of three craters named Philby-A (64 m diameter), Philby-B (116 m diameter), and "11 m crater", all of which since their discovery have experienced repeated infilling and excavation by aeolian sands (Gnos et al., 2013). The Wabar site was known to the local Bedouins for generations, but remained undescribed until visited by the British explorer H. The name Wabar is a transliteration of Ubar, but is not the actual site of the legendary lost city that was rediscovered in 1992 at a site 400 km south of the Wabar site. WABARĪ massive meteoric aerial burst equal to ~12 kilotons lit up the sky over desert sands in the Empty Quarter of the Rub' al Khali, Saudi Arabia, at a site known as Wabar or "Al Hadidah" (= the iron) in Arabic. WABAR PHOTO To display this page you need a browser with JavaScript support.
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