Written in English
Reprinted from Geological Journal (University of Birmingham), Vol. 6, Pt. 2, 1969.
Le M~tour et al. () produced a , geological map of Masirah and described the folded Upper Cretaceous Fayah Formation from the island. Paleomagnetic studies on ophiolites, predomi- nantly on the extrusive members and associated sedi- ments, are widely used for paleogeographic reloca- tion of ancient ocean floor fragments (e.g Cited by: Oman has two ophiolites – the better known late Cretaceous northern Oman (or Semail) ophiolite and the lesser known and smaller, Jurassic Masirah ophiolite located on the eastern coast of the Author: Hugh Rollinson. Oman has two ophiolites – the better known late Cretaceous northern Oman (or Semail) ophiolite and the lesser known and smaller, Jurassic Masirah ophiolite located on the eastern coast of the. Simplified geological map of Masirah Island, Oman (after Peters et al., , Peters and Mercolli, ) showing the Jurassic upper and lower ophiolite nappes and the mid-Cretaceous alkaline basalts and intrusives. Inset map shows the location of Masirah Island and Ras Madrakah in Oman relative to the north Oman Mountains ophiolite.
The gabbros have Late Jurassic-Early Cretaceous ages ( Ma), and the granites have broadly similar ages ( Ma). Because the gabbros are likely to give ophiolite formation ages and the granites ophiolite emplacement ages, it can be concluded that the Masirah ophiolite was emplaced very soon after formation. Kaolin deposits >10 m thick overlie unconformably a Mesozoic ophiolite sequence at Jabal Humr, Masirah Island, Oman. The clay's mineralogical and chemical composition, plasticity and moisture. The upper Cretaceous ophiolite complex of Masirah Island Oman. unconformably overlain by unfolded Eocene limestone and is correlated with the Upper Cretaceous Semail Complex of the Oman. Masirah Island (Arabic: جَزِيْرَة مَصِيْرَة , romanized: Jazīrat Maṣīrah), also referred to as Mazeira Island and Wilāyat Maṣīrah (Arabic: وِلَايَة مَصِيْرَة ), is an island off the east coast of mainland Oman in the Arabian Sea, and the largest island of the is 95 km (59 mi) long north-south, between 12 and 14 km ( and mi.
Masirah is an arid, relatively low-lying island facing the Indian Ocean off the eastern coast of Oman at latitude 21 degrees north. The ophiolite sequence is older than that of northern Oman. The population lives from fishing. Masirah Island lies off the SE coast of Oman and comprises a fully developed, though tectonically disturbed ophiolite, unconformably overlain by early Tertiary limestone. The ophiolite consists of harzburgites, cumulate gabbros, a sheeted dyke complex, and pillow lavas with sediment intercalations. Ophiolites also build Masirah Island, situated over km to the SSE of the Batain area (Figure 1). The uppermost Jurassic/lowermost Cretaceous Masirah ophiolites, however, formed earlier than the mid-Cretaceous Semail ophiolite in the Oman Mountains [Beurrier, ; Immenhauser, ] and. A reconnaissance survey of the Km\(^2\) of Masirah Island, Oman, has revealed a fully-developed ophiolite complex which is believed to represent a fragment of Cretaceous ocean crust and upper mantle generated at a constructive plate margin. The complex consists of mantle serpentinites, plutonic rocks ranging from dunite to trondhjemite, a sheeted dyke complex and pillow lava-sediment.