Meta-carbonatites in the metamorphic series below the Semail Ophiolite in the Dibba zone, northern Oman Mountains

Abstract

The meta-carbonatites occur as flows, sills or constituents of meta-tuffites. An intimate association with alkaline basaltic meta-pillow lavas, meta-hyaloclastites, meta-pillow breccias, meta-tuffites, meta-radiolarian cherts and meta-siliceous carbonates can be observed. The succession represents a suite of subaerial and subaquatic volcanic rocks deposited together with deep sea sediments. The meta-carbonatites are geochemically characterized by high P2O5 contents and Ce, La and Nd contents between 500 ppm and 15 000 ppm. Initial 87Sr/86Sr ratios between 0.7037 and 0.7043 confirm a mantle source for the analyzed meta-carbonatites. The meta-volcanics associated with the meta-carbonatites are considered to be the metamorphic equivalents to the mid-Triassic non-metamorphic alkaline volcanic rocks from the Haybi complex and the Umar group. -from Authors