The physical and structural features of the Cairnsmore of Fleet granite and its aureole

Abstract

Synopsis The Cairnsmore of Fleet granite is emplaced into Lower Palaeozoic sediments the structure of which is not completely known. The granite exhibits a decrease in biotite content towards the centre, and passes into a biotite-muscovite granite. The outer contact is everywhere sharp and the aureole restricted in width except in the N.E. and S.W. Field evidence indicates steep contacts, but gravity results suggest that at depth they are less steep and that the present outcrop is near the roof of a batholith. The foliation (flow and shear) is generally concordant with the contact except in the S. and S.W. and has the form of a dome structure slightly offset to the S.W. relative to the outcrop. There appears to be no relation between the foliation and the joints and veins in the granite.