Hydrothermal mineralization in the Iceland rift zone (Tectonic control of the formation of mineral concentrations)

摘要

Distribution, timing, and sequence of hydrothermal mineralization in the Iceland rift zone are discussed. Vein and pore mineralization in basalts confined to the fissure-dike swarm is considered. Intermittent formation of siliceous and other hydrothermal minerals is established at a sufficiently prolonged existence of hydrothermal system. Formation of parallel-layered smectite-zeolite segregations in the course of extension and origination of open fissures and groundwater level fluctuations is analyzed. Local concentration of silica in the plateau basalt-hosted fissures and cavities, as well as accumulation of banded siliceous segregations (onyxes), is ascribed to the multiple intermittent inputs of solutions into the basalt mineralization zone. (PUBLICATION ABSTRACT)