Evidence of a pre-tectonic origin for the auriferous vein-type mineralization of the Dolgellau gold belt, North Wales

摘要

Quartz-sulphide veins that cut Middle to UpperCambrian sedimentary and intrusive rocks in coastal exposures atFriog, south of Fairbourne, Gwynedd, Wales, show featuresconsistent with Acadian deformation, including folds, boudins andcleavage. In the closely adjacent Dolgellau gold belt abundantquartz-sulphide veins, some of which are auriferous, occur at thesame stratigraphic level. Field examination of the gold-belt veinshas revealed deformational features similar to those exhibited atFriog. The textural and mineralogical similarities of the twooccurrences of veining indicate that they are both part of a regionalset of veins that are pre-tectonic with respect to Acadiandeformation-not post-Acadian, as was previously considered.