Publisher © Czech Geological Survey, ISSN: 2336-5757 (online), 0514-8057 (print)
Peculiar lamprophyric rock from Dobré, Orlické hory Piedmont
Abstract
An ultrapotassic lamprophyric rock from NE vicinity of Dobré displays some textural features typical of plutonic vaugnerites and other 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 albiteand quartz. The following hydrothermal stage of evolution resulted in quartz and calcite infilling of vughs and in a pervasive hydrothermal alteration of the whole rock (namely albitization and formation of hydrobiotite).
