Publication at Faculty of Science |
2011
Abstract
An ultrapotassic lamprophyric rock from Dobré compositionally corresponding to minette displays some textural features typical of plutonic vaugnerites combined with those typical of subvolcanic rocks. Early plutonic crystallization was suddenly disrupted perhaps due to explosion in a shallow level of the small-volume magma system.
Release in pressure of volatile constituents leading to a strong undercooling is recorded in very fine granophyric and spherulitic crystallization. Subsequently, increasing concentration of water in the residual melt caused late magmatic, relatively coarse crystallization of albite and quartz followed by products of hydrothermal stage.