Results of integrated geological-geophysical examination of Makhtesh Ramon area (southern Israel) on diamond-bearing associations

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Larson in 1991 put forward a hypothesis on the extremely high development of diamond-bearing kimberlites in the Mid-Cretaceous period. In Israel, the Cretaceous magmatic activity is well known in the central Negev. The first microdiamond in Israel was found in northern Negev and the authors associated its origin with an extraterrestrial event. An integrated analysis of several geological and geophysical factors enables us to select for detailed investigations the area of Makhtesh Ramon canyon situated near the town of Mizpe-Ramon (nothern Negev). Data of aero- and land magnetic surveys as well as self-potential method were analyzed using modern interpreting methods. Application of geochemical/geophysical ion-selective analysis testifies to presence of kimberlite-like bodies located at a small depth. Performed mineralogical analyses of subsurface geological associations allowed to identifying a variety of minerals of diamondiferous association: chrome-diopside, orange garnet, bright-crimson pyrope, picroilmenite, black spinel, olivine, anatase, tourmaline, aggregates of perovskite, yttrium phosphate, moissanite and corundum. The recent geochemical analyses signify to discovering of quasi-kimberlite rock -- meimechite, traces of REE and some platinum group elements also testify presence of diamondiferous associations. Finally, five diamonds (with a size exceeding 1 mm) and more than 400 microdiamonds (< 1 mm) have been discovered in this area. Thus, we can unambiguously concluding that the Makhtesh Ramon area contains typical products of kimberlite pipe destruction.