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. Tla v rudišču so danes pokrita z do dva metra debelo plastjo poplavnih sedimentov (volumen 680 m 3 ). Rudišče seka več naravnih votlin in s sigo zapolnjenih razpok, kakor tudi podorno dvorano v apnencu, katere izvor ni jasen. Iz ocene prostornine izkopa smo določili, da so v rudniku nakopali približno 1100 ton čistega železa. Mineraloške (rentgenska difrakcija) raziskave so pokazale, da je ruda pretežno goethitno-limonitna z opazno vsebnostjo hematita. Geokemične (rentgenska fluorescenca) analize pa kažejo na zelo čist goethite, z vsega enim odstotkom nečistoč. Med elementi v sledovih so najbolj pogosti W (248 ppm), As (168 ppm) in Co (124 ppm) vseh ostalih pa je manj kot 37 ppm. Prejšnje raziskave so pokazale da se ruda razteza na površini ACTA CARSOLOGICA 37/2-3 - 2008 242 show the highest concentrations, with all others < 37 (Ba) ppm. Former prospecting results show that the deposit has a spatial extent of 300 x 200 m with a maximal thickness of about 10 m. Textural, mineralogical and geochemical criteria suggest that the ore body could be of speleogene origin, i.e. deposited in a hypogene, deep phreathic setting, possibly before regional uplift or even prior to the maximal burial depth. A possibly similar ore-body is for example described from the gigantic Lower Cretaceous and sand-filled cave of Wülfrath (North RhineWestphalia, Germany) (Drozdzewski et al. 1998).

Problem statement: Al-Harida volcano is located in the Jordanian parts of the Harrat Al-Shaam plateau and contains considerable amounts of mantle xenoliths within its pyroclastic successions. Approach: These xenoliths are reported for the first time for this area. Mineralogical investigations show that they are composed of olivine, orthopyroxene, clinopyroxene, spinel and phlogopite. Results: The xenoliths range in size from 5-30 cm with an average of 10 cm. They are classified as Type I and belong to the Cr-diopside group and are characterized by high contents of MgO, Cr and Ni. The occurrence of hydrous mineral phases and the enrichment of incompatible elements such as Sr, Rb and Ba indicate a considerable mantle metasomatism. Conclusion/Recommendations: Thermobarometry of the studied xenoliths indicates a temperature ranging from 960-1040°C and pressure ranging from 11-13 Kbar which corresponds to a depth of origin of about 43 km

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