During the final stages of consolidation of granitic magma the volatile-rich residualsolutions may induce widespread alterations, so that pre-existed minerals are veind or replaced by new ones.
Laumontite and stilbite resulting from these processes occuurs generally in veins cutting plutonic rock masses, and these zeolites are also in association with albite and hydrogrossularite mineralization, especially in granodiorite masses.
The alteration zones along zeolite veins can be a very effective mechanical agent of rock weathering and thus allowing other weathering agencies accese to the interior of the rock is a phenomenon frequently observed.
The significance of these alteration to deeper seated weathering are discussed in this paper.