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Department of Geology, Laval University, Ste-Foy, Quebec, Canada G1K 7P4
The layered ultramafic and mafic rocks forming the early plutonic assemblage of the Troodos ophiolite are crosscut by intrusive bodies of poikilitic perioditite. These late intrusions of lherzolitic composition congregate near the base of the crust and rim the diapiric mantle dome (Mount Olympus) of harzburgite which outcrops in the core of the plutonic complex. Their parental magma consisted of extensively melted mantle peridotite with addition of basaltic melt. This mixture or crystal-liquid suspension of high ‘yield strength’ is assumed to have been generated in a mantle diapir within the subduction zone environment. The mantle diapir has reached the base of the Troodos crust, deformed the crust and released crystal mushes resulting in the intrusion of peridotite bodies into the crust.
