Atlantic Geoscience Society ABSTRACTS
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Atlantic Geoscience Society ABSTRACTS 43rd Colloquium & Annual General Meeting 2017 FREDERICTON, New Brunswick The 2017 Colloquium & Annual General Meeting was held at the Fredericton Inn, Fredericton, New Brunswick, on February 10th and 11th. On behalf of the society, we thank Colloquium organizers David Lentz, Dave Keighley, Chris McFarlane, Anne Timmermans, Robin Adair, Jim Walker, Susan Johnson, and Mike Parkhill, as well the numerous student volunteers and judges, for facilitating an excellent meeting with a record 110 abstracts. AGS acknowledges support from the corporate sponsors of the meeting: the University of New Brunswick Fredericton, New Brunswick Branch of the Canadian Institute of Mining, Metallurgy and Petroleum, Engineers and Geoscientists New Brunswick, New Brunswick Department of Energy and Resource Development, New Brunswick Department of Environment, Wolfden Resources Corporation, AMEC Foster Wheeler, Dillon Consulting, Mining Matters, Avalon Advanced Materials Incorporated, Potash Corporation of New Brunswick, and Pretium Resources Incorporated. In the following pages, we are pleased to publish the abstracts of oral and poster presentations from the meeting, which included a Symposium on “The Northern Appalachian Orogen: Correlations and Conundrums” and five Special Sessions: (1) Museum and University Geology/Paleontology Collections” – in memory of Don Reid, ONS (1922–2016); (2) Magmas and Metals; (3) Environmental Geoscience in the Atlantic Provinces and Beyond; (4) Advances in Carboniferous Geology in the Atlantic Provinces – in memory of Dr. Wouter van de Poll (1932–2017); (5) Where on Earth?: Education, Integration and Development of Earth Science for Social Benefit in Atlantic Canada, as well as General Sessions on “Current Research in the Northern Appalachians and North Atlantic Margin.” Gesner Medal 2017 recipient, Rebecca Jamieson, presented the Geological Association of Canada, Howard Street Robinson Lecture “How do large hot orogens work? Lessons from the middle crust”. Stephen Piercey presented his GAC Hutchison Lecture on “The importance of magmatism in the genesis of the Wolverine volcanogenic massive sulphide (VMS) deposit, Yukon, Canada: constraints from lithogeochemical, Nd-Hf isotope, and in situ U-Pb-Hf isotope data” in the special session on Magmas and Metals on Saturday afternoon. Also included with the conference was a half-day workshop on “pXRF applications in Geologic Research and Exploration” by David Lentz (University of New Brunswick). A two-day teacher’s workshop and an evening Earth Science Café, organized by Anne Timmermans and Catherine O’Connell-Cooper (University of New Brunswick, Quartermain Earth Science Centre), were also part of the weekend. The guest speaker at Saturday evening’s banquet and social was Randy Miller (Emeritus New Brunswick Museum, UNB Adjunct) who gave an enlightening talk on the history of the New Brunswick Museum, its collections, and early New Brunswick Geologists, titled “Maybe I could try geology”. The Editors ATLANTIC GEOLOGY 53, 127 - 184 (2017) doi: 10.4138/atlgeol.2017.006 Copyright © Atlantic Geology 2017 0843-5561|17|00127-184 $9.70|0 Atlantic Geology Volume 53 .. 2017 128 forward modelling of variations in dyke orientation, and Inferring post-Jurassic movement of the Oak Bay depth to top across the fault constrained by measurements Fault through acquisition and modelling of magnetic of remnant magnetization, magnetic susceptibility, profiles across the MinistersI sland Dyke in Brooks and dyke width available from previous studies. Cove, Maine, USA* 1 1 2 *Winner of the AGS Rob Raeside Award for best Jennifer Adam , Karl Butler , and John Evangelatos undergraduate student poster 1. Department of Earth Sciences, University of New Brunswick, 2 Bailey Drive, Fredericton, New Brunswick E3B 5A3, Canada <[email protected]> ¶ Diagenetic effects and fluid flow along erosional 2. Department of Earth Sciences, Dalhousie University, 1355 boundaries and unconformities in the Triassic Wolfville Oxford Street, Halifax, Nova Scotia B3H 4R2, Canada Formation at Rainy Cove, Nova Scotia, Canada The Ministers Island Dyke in southwestern New Brunswick trends ENE-WSW from eastern Maine across Erin D. Anderson and Grant D. Wach the St. Croix River, St. Andrews peninsula, Ministers Island and beyond into Passamaquoddy Bay. The dyke Basin and Reservoir Lab, Department of Earth Sciences, Dalhousie is a quartz tholeiite, approximately 180 Ma in age, and it University, Halifax, Nova Scotia B3H 4R2, Canada crosses the near-perpendicular Oak Bay Fault beneath <[email protected]> the St. Croix River. An aeromagnetic survey acquired in 2001 revealed a kink in the trend of the strong linear Rainy Cove lies along the south shore of the Minas magnetic anomaly associated with the dyke beneath the Basin on mainland Nova Scotia. Outcrops along the beach river, and prompted re-evaluation of an earlier conclusion preserve fluvial barforms and channel deposits of the that all significant movement on the Oak Bay Fault had Wolfville Formation, a member of the Fundy Group. The ceased prior to dyke emplacement. In particular, it has Triassic Wolfville sandstones lie unconformably over the long been questioned whether elevated seismicity in the steeply dipping metasedimentary rocks of the Carboniferous region is a result of recent movement along this fault. Horton Group. Within the Wolfville Formation, there In 2005, University of New Brunswick researchers is a hierarchy of erosional surfaces and unconformities conducted a higher resolution marine magnetic survey in separating lithofacies packages. These range from barform the St. Croix River in an effort to confirm whether faulting surfaces marking small reactivations in fluvial sedimentation has displaced the dyke. This survey delineated the dyke to an intra-Triassic unconformity that incises 10 m into anomaly on the eastern side of the Oak Bay Fault, but previously deposited barforms. The infill is a multi-storied the boat could not travel sufficiently far into the shallow channel complex demonstrating several episodes of cut and waters of Brooks Cove, Maine, to define the dyke anomaly fill. Previous research on the Wolfville Formation has not to the west. In 2016, a shallow-water marine magnetic investigated these erosional surfaces. Heterogeneities in survey was undertaken by kayak to acquire additional porosity and permeability along erosional boundaries could magnetic profiles that follow the coastline more closely. create preferential pathways, baffles, or barriers to fluids in The kayak survey was centered in Brooks Cove and the subsurface. The objective of this study is to investigate spanned approximately 1 km on either side of the cove. A diagenetic variance across the erosional boundaries and the proton precession base station magnetometer was set up potential impacts on fluid flow. Measured sections from the onshore, while the surveying Overhauser magnetometer was outcrop describe the lithofacies changes across the surfaces, aboard the kayak. The surveying magnetometer collected and handheld gamma ray scintillometer/spectrometer readings once every second along lines approximately measurements record changes in radioactive mineral 50 m apart, while a Garmin GPS receiver, carried 2.5 m content to supplement lithologic observations. The Wolfville behind the magnetometer, recorded a position every two Formation at this location is a coarse-grained, subangular to seconds. Preliminary gridding of the data into a magnetic angular red sandstone that is well cemented with carbonate. field map shows dramatic weakening of the anomaly over Petrographic analyses of samples above and below bounding a span of 100 m across the Oak Bay Fault – suggestive of surfaces show that the sandstones have undergone varied demagnetization in the fault zone – as well as curving of paragenetic processes including burial cementation, limited the dyke anomaly on either side of the fault – suggestive mechanical compaction, partial dissolution of unstable of dextral offset of approximately 300 m. This dextral feldspars and cements, and alteration. Cements tend to offset opposes sinistral displacement that has previously be sparry and void filling, which is characteristic of the been inferred for the Oak Bay Fault based on older cross- phreatic zone. Some samples also show bladed grains or cutting relationships. Further investigations will include thin cement rims. Dull cathodoluminescence of the cement Atlantic Geoscience Society 2017 - ABSTRACTS Copyright © Atlantic Geology 2017 Atlantic Geology Volume 53 .. 2017 129 suggests formation in a burial environment with higher related to the nature and type of organic material, source Fe/Mn ratio, and zoning of some cement crystals indicates rock maturity trends and organic richness in the Green multiple phases of diagenesis. Presence of pore-filling River Formation. As a consequence of deposition in low- cement impedes fluid flow within lithofacies packages, energy lacustrine environments, shallow burial, and the which may create preferential pathways along the varied general immaturity of Green River Formation source erosional surfaces. rocks, some sub-millimetre scale sedimentary structures and features have been preserved and might enable further insight into any relationships between the elements of this study. While the influence of microbial communities and Trace-element variation associated with diagenetic organic material on pore-water chemistry is not precisely phosphate and sedimentary organic