Geochemical characters of the gabbroic rocks in ophiolite sequences of North Hatta Area, United Arab Emirates

The ophiolite sequences of UAE, as a part of Oman ophiolite, represent both, mantle section and crustal section. The crustal part of the ophiolite sequences, consists of a layered series (cumulate peridotites and gabbros). This paper aims to overview geochemical character and some mechanical and physical features of the gabbroic rocks. The gabbros comprise troctolite, olivine gabbro, normal gabbro, gabbronorite, and uralitized gabbros. Geochemical features indicate that they are tholeiitic and are formed in an arc-related tectonic setting. On NMORB normalized pattern of gabbros, the HFS-elements (P, Zr, Sm, Ti, and Y) show a flat pattern parallel to NMORB. In contrast, the LIL-elements (Rb, Ba, Th, Sr) are relatively more enriched than NMORB. The enrichment of LIL-elements over the HFS-elements and the depletion of Nb relative to other HFS-elements suggest involvement of subduction component in the depleted mantle source, and suggest that these rocks were formed in a supra-subduction zone tectonic setting.