Granodiorite pipelike bodies occur in meladiorites of Guernsey in the Channel islands. They average about three inches in diameter, connect downwards with an acid vein system or layer, and are all similarly inclined. Genesis probably involved formation of a leucodiorite, intrusion of vein material, intrusion of meladiorite, rise of vein material as pipes into the meladiorite magma, relative movement of rocks above and below the meladiorite, fissure formation and filling with acid magma from the vein system, and westward tilting of the layers through 20 degrees before solidification of the pipes.

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