Architecture of Gold Mineralization at Anomaly A of the Clarence Stream Deposits, Southern New Brunswick

摘要

The Anomaly A area of the Clarence Stream gold deposits in southwestern New Brunswick contains mineralized structures that bear geometrical relationships to regional folding events. The four mineralized zones of Anomaly A (AD, MW, 93, and Murphy) are hosted by turbiditic gray-wacke, quartzose wacke, siltstone, and argillite sequences of the Kendall Mountain Formation. A regional scale structural analysis reflects at least four deformational events, three of which appear to control the folded geometry of Anomaly A (D_2, D_3, and D_4). F_2 and F_3 folds are coaxial and are refolded into a dome and basin geometry by F_4 folds. The mineralized zones are subparallel to axial surfaces of F_2 folds. Structural analysis of a mineralized zone exposed at surface indicates that gold mineralization is hosted by a quartz-vein system that comprises veins generated during both D_2 and D_3. Three-dimensional representations of Anomaly A created using drill-core data and ~RGoCAD suggest that the quartz-vein system was emplaced in fault structures during D_2 as well as within brecciated dilation zones during D_3. Three of the four zones that make up Anomaly A have F_2 hinge surfaces that can be linked through a geometry compatible with the style of F_3 and F_4 folds. The apparent continuity of these three zones indicates the potential for kilometer-scale mineralized structures at Anomaly A.