• Home

Scientists analyse rocks in Hajjar Mountains

AL AIN — Professor Benjamin R. Jordan of the Department of Geology at the UAE University said that with the exception of the south-western Ruus Al Jibal, the rocks exposed within the Hajjar Mountains in the country differ markedly from those that contain deeply buried oil and gas fields in the west and beneath the southern Gulf.

He highlighted that the origin of the sub-surface rocks that underlie the greater part of the emirates is known in relatively simple terms, but the geology of the mountains is less well known and its interpretation is controversial. This mountain area is the location of the world’s largest and most intact ophiolite complex.

“Ophiolites are pieces of the oceanic plates that have been thrust onto the edge of a continental plate. They are made up of assemblages of mafic and ultramafic lavas and hypabyssal rocks,” added Professor Benjamin. One school of thought favours an origin in an intra-oceanic arc setting for the development of the Semail ophiolite; the other believes that the rocks of the ophiolite were created at a mid-oceanic ridge. He added that these two models have different implications for the mineral-deposit potential of the region. The ophiolitic rock of this area is cut by numerous silicic dikes. Evolved silicic rocks often form pegmatitic minerals containing concentrations of elements in economically mineable quantities.