Genetic links among fluid cycling, vein formation, regional deformation, and plutonism in the Juneau gold belt, southeastern Alaska
Gold-bearing quartz vein systems in the Juneau gold belt formed within a 160-km- long by 5- to 8-km-wide zone along the western margin of the Coast Mountains, Alaska. Vein systems are spatially associated with shear zones adjacent to terrane-bounding, mid-Cretaceous thrust faults. Analysis of vein orientations and sense of shear data define a stress configuration with greatest and least principal axes oriented subhorizontally with northeast-southwest trends and subverticaly, respectively. This local stress configuration is compatible with the far-field plate configuration during Eocene time. Isotopic ages of vein formation indicate that fluid cycling occurred between 56.5 and ≥52.8 Ma, and are consistent with a genetic link between veining and a change in plate motion in early Eocene time. Veining was also synchronous with the latter stages of rapid exhumation and voluminous plutonism immediately inboard of the gold belt. We propose a model in which interacting tectonic events facilitated fault-valve action and vein development along now-exhumed shear zones.
Citation Information
Publication Year | 1994 |
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Title | Genetic links among fluid cycling, vein formation, regional deformation, and plutonism in the Juneau gold belt, southeastern Alaska |
DOI | 10.1130/0091-7613(1994)022<0203:GLAFCV>2.3.CO;2 |
Authors | Lance D. Miller, Richard J. Goldfarb, George E. Gehrels, Lawrence W. Snee |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Geology |
Index ID | 70187597 |
Record Source | USGS Publications Warehouse |