- journal_title：Bulletin de la Societe Geologique de France
- Contributor：Khadidja Abbou-Kebir ; Shoji Arai ; Ahmed Hassan Ahmed ; Georges Ceuleneer
- Publisher：Societe Geologique de France
- Date：2013-03-01
- Format：text/html
- Language：en
- Identifier：10.2113/gssgfbull.184.3.261
- journal_abbrev：Bulletin de la Societe Geologique de France
- issn：0037-9409
- volume：184
- issue：3
- firstpage：261
- section：Invited Paper
Peculiar dunitic veins almost or totally free of spinels crosscut a podiform chromitite ore body in the Wadi Rajmi, northern Oman ophiolite. They probably originated from a komatiitic melt which was oversaturated in Fo<sub>≤94sub> olivines and which evolved to precipitate simultaneously both chromian spinels, with Cr# ranging from 0.6 to 0.8, and Fo<sub>91-93sub> olivines. The absence or the low modal amounts of spinels are possibly governed by a Cr-undersaturation state of the involved melt which crystallized under relatively low cooling rates to generate the spinel-free and the spinel-poor dunites. A shallow and highly depleted mantle source for this komatiitic melt was envisaged during a converging tectonic regime, initiated earlier in the dynamic history of the Oman ophiolite.