Magmatic outgassing

Staudigel H., Hart S. R., Schmincke H. U., and Smith B. M. (1989) Cretaceous ocean crust at DSDP sites 417 and 418 Carbon uptake from weathering versus loss by magmatic outgassing. Geochim. Cosmochim. Acta 53, 3091-3094. 

The display of dates in Fig. 4.9 also demonstrates that the whole-rock K-Ar dates of the Priestley Schist are lower than those of the Priestley Slate and that they overlap the K-Ar and Rb-Sr dates of biotite of the Granite Harbor Intrusives of the Terra-Nova-Bay area. This observation confirms the hypothesis that the rocks of the Priestley Schist were outgassed during the magmatic activity that accompanied the Ross Orogeny. The Granite Harbor Intrusives and the Priestley Schist subsequently cooled at about the same rate until the Middle Ordovician at about 450 Ma. 

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