[ad. F. vulcanisme, var. of volcanisme VOLCANISM.] Volcanic action or condition.
1877. Le Conte, Elem. Geol., III. (1879), 93. The sun may be regarded as a globe in an earlier and more active stage of vulcanism.
1883. Nature, XXVII. 280. The … strata which have been deposited … under the combined influences of internal vulcanism and external atmospherical influences.
