James M. Franklin

Morphology, Distribution, and Estimated Eruption Volumes for Intracaldera Tuffs Associated with Volcanic‐Hosted Massive Sulfide Deposits in the Archean Sturgeon Lake Caldera Complex, Northwestern Ontario

The Archean Sturgeon Lake Caldera Complex (SLCC) comprises a well-preserved, north-facing homoclinal sequence of greenschist facies metamorphosed intrusive, volcanic, and sedimentary strata. This piecemeal caldera complexis at least 25 km in strike length and contains nearly 3000 meters of dominantly subaqueously deposited intracaldera fill. Episodes of subaerial and subaqueous explosive felsic volcanism produced rhyodacitic to rhyolitic tuffs and lapilli tuffs. Progressing stratigraphically upward, the most voluminous are: a) the High Level Lake Tuff (∼16km 3 ); b) the Mattabi Tuff (∼27km 3 ); and c) the Middle L Tuff (∼7km 3 ). The subaerially erupted, subaerially and locally subaqueously deposited High Level Lake Tuff comprises an 80-300 meter-thick unit composed of basal, poorly sorted, massive to normal graded, quartz-phyric, locally spherulitic tuffs and lapilli tuffs (30-150m thick) that are overlain by thin-bedded tuffs (<1-5m thick). The subaqueously erupted and deposited Mattabi Tuff contains up to thirteen individual flow units, each comprising two distinct depositional facies: a) lower, quartz-phyric, poorly sorted, ungraded, massive tuffs and lapilli tuffs (20-250 meters thick); and b) upper, laminated to medium bedded, typically normal graded tuffs (1-13 meters thick). The subaqueously erupted and deposited Middle L Tuff is also characterized by two distinct lithofacies: a) lower graded, quartz- and, rarely, potassium feldspar-phyric tuffs and lapilli tuffs (5-120m thick); and b) overlying, well-sorted, laminated to thickly bedded, normal graded tuffs (<1-5m thick). These three voluminous tuff deposits host all known volcanic-hosted massive sulfide (VHMS) ore bodies in the SLCC. At Sturgeon Lake, VHMS ore deposition appears to be favored by processes associated with the generation of voluminous subaqueous explosive eruptions.

ROV samples vents on Juan de Fuca Ridge

In 1991, the JASON Remotely Operated Vehicle (ROV) successfully performed high-resolution imaging within complex vent fields on the northern Juan de Fuca Ridge. From June 22 to July 16, 1992, a team of Canadian and U.S. scientists and engineers joined in an expedition to develop sampling capabilities for a HYSUB 5000 ROV in a mid-ocean ridge hydrothermal vent environment. Our experience on the Juan de Fuca Ridge is another starting point for pursuing the science capabilities of deep-water ROVs. The Remotely Operated Platform for Ocean Science (ROPOS) was built by International Submarine Engineering and is operated by the Institute of Ocean Sciences in Sidney, British Columbia. The cruise was staged off the National Oceanic and Atmospheric Administrations ship Discoverer, based at NOAAs Pacific Marine Center in Seattle, Wash. Support for the expedition came from the Department of Fisheries and Oceans Canada, the Department of Energy Mines and Resources Canada, the NOAA Vents Program, and the Natural Sciences and Engineering Research Council Canada.

Acceptance of the R. A. F. Penrose Gold Medal for 2014

Thank you, Howard, and to Francois and SEG: It’s a humbling experience to be awarded SEG’s Penrose Medal. I looked at the list of previous winners and realize the exceptional contributions that all of them have made to our profession. I’m honored to join such a distinguished group, and just hope that my continuing activity in our profession comes even close to meeting the standard set by these earlier recipients, both recent and historic. Achieving success in our business requires at least three things: 1. Continuing curiosity about mineralization processes and the attributes of ore deposits will enable us to make new discoveries with greater and greater precision. As seen at this meeting, the researchers and students of today are making enormous strides, using the latest technology along with good, solid fieldwork that involves little more than a hand lens and the compass, to advance our understanding and consequently improve the exploration efficiency of our industry. We have learned at this conference and throughout our careers as geoscientists that the complex, multidimensional problems attendant on ore formation are not easily, if ever, completely solved. We all must accept that our models are somewhat incorrect, that we must never take ourselves too seriously in our pronouncements about solutions to problems attending the processes that …

Geology, Geochemistry and Genesis of the Greens Creek Massive Sulfide Deposit, Admiralty Island, Southeastern Alaska

Cliff D. Taylor and Craig A. Johnson, Editors. U.S. Geological Survey Professional Paper 1763, 429 Pp., 7 plates on CD. ISBN 978-1-4113-2622-4. Available at no cost online, at >. Also available from the editor; e-mail, ctaylor{at}usgs.gov. Documentation of important