Previous Issues

Department of Geology. University of Kuwait

ABSTRACT

Fresh spinel-lherzolite xenoliths were found in the Quaternary alkaline olivine basalts from Shihan Volcanic Cone, central Jordan. Mineralogically, they consist of forsterite, Fe-enstatite, chrome-diopside and chrome-spinel set in a protogranular texture. Two generations of these minerals can be traced. Phlogopitisation of olivine is a common feature, especially for generation I forsterite. The enclosing basalt is highly contaminated by detached mineral fragments from the xenoliths. Fissure eruption dolerites exposed in nearby areas are tholeiitic and are not the feeders for Shihan basalts. It is possible that the mono-xenoliths in Shihan basalts were derived from the upper mantle and that the central volcano type eruption accompanied transcurrent faults rather than norma1 faults