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Infrastructure development cannot take place without gravel, which is scarce in the North American Arctic. Conditioning where development can occur, the commodity has become the target of Indigenous actors seeking to secure land and resource bases and their material futures, too. In Alaska, decades of litigation pitting Indigenous surface versus subsurface corporate landholders has contested gravel's legal location. In Canada, contrastingly, Inuvialuit land claims negotiators successfully secured access to granular resources. In both locales, legal processes have resulted in certain Indigenous actors' accumulation of geologic power. Rooted in the subterranean, this power enables them to transform the surface of the Earth. Contributing to research on geologic power and political geology and drawing on fieldwork and a review of court cases, policy documents and reports, this article critiques how gravel has become an Arctic resource lucrative to local communities rather than global markets and a key source of Indigenous political and economic agency. Going forward, struggles over Indigenous rights may concern securing ownership over not only the land base, but the land column., (© 2023. The Author(s) under exclusive licence to Royal Swedish Academy of Sciences.)

Excavating what Jeffrey Cohen [2015. "Stone: An ecology of the inhuman." Minneapolis: University of Minnesota Press] calls "lithic ecomateriality," in this paper we illustrate how rocks have traditionally been conceptualized through three tropes: rocks as insensate; rocks as personified; and rocks as transformative. We take up the concept of inhuman to challenge human-centric taxonomies of rocks and animacy. If rocks are not lifeless, or only considered as "resources" or "threats," to humans, then thinking with rocks as vital extends our ethical and political response. In the final section of the paper, we consider archives, not as a logical form of organizing knowledge, but as material, vital, and affective. We argue that when stones and archives are examined as something more than stable things--as interfactual, transcorporeal, and transmaterial co-compositions--different ethical relatings to the inhuman world become possible.

From the late 1940s to the late 1950s, the Geological Survey of Canada (GSC) turned vigorously to the Arctic archipelago, expanding and confirming the colonial premise that the islands of the High Arctic were an extractive frontier for oil and gas. In this paper, the first of a planned pair, we show how the efforts of the GSC were hugely consequential for subsequent corporate hydrocarbon exploration, but were also intimately entangled with other, concurrent strands of militarization and Arctic colonialism. Numerous histories celebrate GSC geologists as heroic pioneers of extraction and northern field science. Both the militarization of the Arctic in the 1950s and the concurrent, infamous High Arctic Relocations have been discussed at length. This paper has a more precise, interstitial objective: to show that the GSC's fieldwork depended on both the infrastructure of Cold War geopolitics and the labour of Inuit who were moved to the region under duress—particularly to the new community of Qausuittuq (Resolute). Regardless of specific commercial outcomes, the version and vision of the Arctic installed by the GSC continues to foreground certain future geographies of the archipelago, while forestalling or marginalizing others. Key messages: The intensive efforts of the Geological Survey of Canada in the middle of the 20th century solidified the southern understanding of the Arctic archipelago as a potential extractive frontier.This mid‐century geological fieldwork was entangled with Cold War militarization and dependent on the coerced relocation of Inuit to the High Arctic.The practices and productions of this fieldwork continue to shape some versions of the Arctic future while forestalling or marginalizing others. [ABSTRACT FROM AUTHOR]

The productivity of milling circuits is sensitive to the size of mill feed. Uncertainty about the size of caved ore presents unique challenges to forecasting and controlling mill throughput rates. Part I of this paper showed how fragmentation size and hang-up frequency relate to geology, proximity of drawpoints to the cave boundary and the height of draw at the New Afton mine. The second part, presented here, investigates the impact of varying caved fragment size on mill performance. Analysis of historical mine and mill data showed that mill feed size and subsequently mill throughput are sensitive to the areas being mucked within the cave. Fragmentation measurements of drawpoint muck, comminution tests and calibrated mill models were used to assess the impact of variations in feed size and hardness on New Afton mill performance. Image-based size analyses of drawpoint muck and comminution tests showed that coarser material generally contained harder rock. [ABSTRACT FROM AUTHOR]

From the late 19th to the late 20th century, the cities and industries of the world became increasingly reliant on fireproof materials made from asbestos. In focusing on the town of Asbestos, Canada, this paper will show how this process of market boom and bust shaped a fierce local culture rooted in working and living on a rapidly changing environment. By analyzing the successive expansions of the giant mine located in the centre of Asbestos, this paper will highlight how unique understandings of self and place develop in mining communities and form a complex culture rooted in a constantly changing environment. [ABSTRACT FROM AUTHOR]

• New carbon-sequestration geosystem paradigm proposed for screening CO 2 repositories. • Deposition, burial history 1st-order controls on repository attributes, traps, etc. • Genetic understanding of geology enables property prediction away from data control. • Case-study application to heavily industrialized region of onshore Canada. In this paper, I propose a new geoscience paradigm for evaluating potential carbon-sequestration targets. I introduce the term carbon-sequestration geosystem to study and describe portions of sedimentary basins where all the geologic components necessary for the safe and long-term storage of CO 2 are present. The purpose of this type of analysis, most appropriately applied at a basin-screening stage, is to derive a holistic, genetic, and predictive understanding of the geology – the depositional systems, structural setting and other factors that are direct controls on storage, injectivity, potential for induced seismicity, and other critical factors. To illustrate the concepts, I present a re-evaluation of the geologic carbon-sequestration options in Southern Ontario (Canada) where business and environmental needs, mostly associated with hard-to-abate industries, require urgent action. Legacy wireline-logs, core, and outcrop data are the main data sources available in this onshore setting. The results of this new, independent study are broadly similar to those of previous studies: the Cambrian section, a saline aquifer, is the most likely candidate to be a CO 2 repository. However, the methodology used identified several issues (e.g., stratigraphic heterogeneity, proximity to basement) that will need addressing by targeted data collection and/or analysis before site-selection for a test should be undertaken. [ABSTRACT FROM AUTHOR]

Nova Scotia possesses a varied and complex geology with many distinct formations in a distinct metallogeny containing many metallogenic units, some of which have a rich and diverse mineral endowment. One such unit would be the Meguma Zone that contains several active mines and prospects with gold and associated minerals of economic interest including several prospects either planned or about to enter production. This paper relates some of the experiences and observations completed during a 15-year period as the provinces' geochemist. My duties included supervising and designing several geochemical databases to assess this rich mineral endowment for economic potential. Several geochemical surveys completed at different scales and in different media facilitate a review of the gold potential within the Meguma Zone lithologies with new areas identified for additional consideration for exploration work presented in the accompanying talk. Presently much interest is held in the traditional Meguma targets of saddle reef quartz-vein systems now eclipsed by the more recent interest in sediment-hosted targets with a similar geology to the Moose River deposit of Atlantic Gold. Another gold environment makes up the three potential target areas in the Meguma - that of shear zone-hosted deposits within the intrusive granitic suites. Several case history examples are given for cost-effective methods for exploration in the Meguma Zone, including soil, till, vegetation, and lake sediments ranging in scale from reconnaissance to prospect scale studies. [ABSTRACT FROM AUTHOR]

This article presents a history of the development of U–Pb geochronology with emphasis on the role of Canadian researchers and some of its applications to Canadian geology. Modern U–Pb dating is the result of work by many individuals over the past 60 years, but the most important was Tom Krogh, who established methods that allowed determination of precise ages (<0.1% errors) on zircon using isotope dilution thermal ionization mass spectrometry. This was followed by the introduction of new analytical approaches by others, notably secondary ion mass spectrometry and laser ablation inductively coupled plasma mass spectrometry that allow intracrystal domains to be dated. U–Pb geochronology is now an indispensable tool for understanding the Earth. In collaboration with field mapping, it has vastly improved our understanding of the geological history of Canada as well as important geological events such as mass extinctions, secular changes in geological processes, and the birth of the solar system. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Climate change poses a significant threat to Arctic freshwater biodiversity, but impacts depend upon the strength of organism response to climate‐related drivers. Currently, there is insufficient knowledge about Arctic freshwater biodiversity patterns to guide assessment, prediction, and management of biodiversity change.As part of the Circumpolar Biodiversity Monitoring Program's first freshwater assessment, we evaluated diversity of diatoms, benthic macroinvertebrates, and fish in North American Arctic rivers. Alpha diversity was assessed in relation to temperature, water chemistry, bedrock geology, and glaciation history to identify important environmental correlates. Biotic composition was compared among groups to evaluate response to environmental gradients.Macroinvertebrate α‐diversity declined strongly with increasing latitude from 48°N to 82°N, whereas diatom and fish diversity peaked around 70°N without a clear latitudinal decline. Macroinvertebrate diversity was significantly positively related to air temperature. Diatom diversity was related to bedrock geology and temperature, whereas fish diversity was related to glaciation history.Fish and macroinvertebrate assemblages differed between sites in western Canada, where invertebrate composition was more variable, and Alaska, where fish composition was more variable. In sites with both diatom and macroinvertebrate data, diatom composition was distinct in Alaska, where richness was highest in former glacial refugia. Macroinvertebrate composition was distinct in lowest‐latitude eastern and high‐latitude western Canadian sites where temperature was highest.Temperature, precipitation, geology, calcium, and substrate size were important environmental correlates for diatoms and macroinvertebrates, although the relative importance of each correlate differed. Diatom taxa were most strongly associated with water chemistry, whereas benthic invertebrate composition related most strongly to precipitation and temperature.This large‐scale study provides the most substantial integration and analysis of river diatom, macroinvertebrate, and fish data from the North American Arctic to date. Findings suggest that macroinvertebrates will show the strongest response to climate‐related shifts in temperature, whereas diatoms and fish are more likely to respond to climate‐induced shifts in nutrients and hydraulic connectivity. However, significant gaps in data coverage limited our ability to reliably evaluate spatial patterns and detect change. These gaps could be reduced by improving collaborative efforts between the U.S.A. and Canada to harmonise future monitoring. [ABSTRACT FROM AUTHOR]

This thematic issue is in memory of Thomas Kurtis Kyser who died tragically in 2017. Kurt's contribution to our understanding of the geochemistry of uranium deposits and the application of stable and radiogenic isotope studies to uranium ore systems is incalculable. His research on uranium deposits included the world-class unconformity-related uranium deposits from Canada, Australia, and Russia, and several other major types of uranium deposits worldwide such as Na-metasomatic deposit of Kurupung (Guyana) and Valhalla (Australia), volcanic-hosted deposits of Peru (Macusani), and vein-type uranium deposits from Beaverlodge district (Canada). He was the first to develop methods to use secondary dispersion of pathfinder elements to vector towards deeply buried uranium ore systems. These new geochemical and isotopic approaches are still successfully applied today. Kurt has been a pioneer in applying stable isotopic systems to characterize the paleofluid events associated with ore systems and to distinguish between barren and mineralized fluid pathways. Kurt was a prolific author with over 400 publications and over a hundred articles on uranium deposits. Kurt wrote three short courses for the Mineralogical Association of Canada dedicated to uranium deposits: Fluids and Basin Evolution (2000), Recent and not-so-Recent Developments in Uranium Deposits and Implications for Exploration (2008, in partnership with SGA), and Geology and Geochemistry of Uranium and Thorium Deposits (2015). However, his true legacy is the large number of undergraduate and graduate students, post-docs, and researchers that he taught, supervised, and mentored; most of whom are now working in industry, academia, and government institutions across the globe. He will be missed. [ABSTRACT FROM AUTHOR]

Although alkalic porphyry Au--Cu deposits are much less common than their calc-alkalic counterparts, they represent attractive exploration targets both due to their occurrence as, locally concealed, clusters and their high Au contents. In this paper, the geology of the Mt. Milligan Au--Cu deposit, Canada, and its geophysical footprint on magnetic and AEM data is used as a case-study for the exploration and discovery of concealed alkalic porphyry Au--Cu deposits. The Cole-Cole parameters in the AEM data are extracted using an improved Airborne Induced Polarization (AIP) mapping algorithm. We propose that the subtle electromagnetic signatures of disseminated sulfides around the intrusive porphyry stocks at Mt. Milligan could be mapped by the m τ product, where m is AIP apparent chargeability, and τ the Cole-Cole time-constant, provided that the depths of the alteration zone does not exceed 75 m. The product is called Tau-Scaled Chargeability or TSC. In order to improve the exploration success in the search for concealed alkalic porphyry Au--Cu deposits, we propose to: (1) concentrate the exploration on known and well-endowed mineral districts; and (2) apply innovative digital data-processing techniques capable of extracting weak and subtle signatures from airborne geophysical data and, subsequently, to utilize DCIP ground surveys in the follow-up of anomalies, ideally in combination with enzyme-leach soil sampling. • Alkalic porphyry Au-Cu deposits are attractive exploration targets due to their high Au contents. • They occur in clusters, typically above fractionating magma chambers in the upper crust. • AIP mapping can define pyrite halos around concealed intrusive stocks at Mt. Milligan. • AIP mapping can be used as a vectoring tool. [ABSTRACT FROM AUTHOR]

Understanding Hadean (>4 Ga) Earth requires knowledge of its crust. The composition of the crust and volatiles migrating through it directly influence the makeup of the atmosphere, the composition of seawater, and nutrient availability. Despite its importance, there is little known and less agreed upon regarding the nature of the Hadean crust. By analyzing the 87Sr/86Sr ratio of apatite inclusions in Archean zircons from Nuvvuagittuq, Canada, we show that its protolith had formed a high (>1) Rb/Sr ratio reservoir by at least 4.2 Ga. This result implies that the early crust had a broad range of igneous rocks, extending from mafic to highly silicic compositions. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Salt marshes are highly effective carbon (C) sinks and have higher rates of soil C burial (per square meter) than terrestrial ecosystems. Marsh reclamation and anthropogenic impacts, however, have resulted in extensive losses of salt marshes. Restoration of marshes drained and “reclaimed” for agriculture (referred to in Canada as dykelands) and degraded marshes can generate C credits, but only if C burial is reliably quantified. To date, studies reporting on C burial rates have been limited primarily to restored marshes which are more than 10 years old. Here we report on a study which assessed C burial six years after the return of tidal flooding to a section of dykeland in Aulac, New Brunswick on Canada’s Bay of Fundy. The C burial rate in the restored marsh averaged 1 329 g C m-2 yr-1, more than five times the rate reported for a nearby mature marsh. Carbon density in the recovering marsh was relatively consistent with depth and although salt marsh cordgrass (Spartina alterniflora) became established in 2012, the bulk of the C in the new marsh deposit is assumed to be allochthonous. Financial constraints are a barrier to marsh restoration projects and C markets could provide a considerable source of funding for restoration work in the future. For marsh restoration projects to be recognized in C crediting systems, however, it must also be demonstrated that the allochthonous C would not otherwise have been sequestered; the potential for this is discussed. [ABSTRACT FROM AUTHOR]

Coiled tubing corrosion was investigated for 16 field water samples (S5 to S20) from a Canadian shale gas field. Weight loss corrosion rates of carbon steel beads incubated with these field water samples averaged 0.2 mm/yr, but injection water sample S19 had 1.25±0.07 mm/yr. S19 had a most probable number of zero acid-producing bacteria and incubation of S19 with carbon steel beads or coupons did not lead to big changes in microbial community composition. In contrast other field water samples had most probable numbers of APB of 102/mL to 107/mL and incubation of these field water samples with carbon steel beads or coupons often gave large changes in microbial community composition. HPLC analysis indicated that all field water samples had elevated concentrations of bromide (average 1.6 mM), which may be derived from bronopol, which was used as a biocide. S19 had the highest bromide concentration (4.2 mM) and was the only water sample with a high concentration of active bronopol (13.8 mM, 2760 ppm). Corrosion rates increased linearly with bronopol concentration, as determined by weight loss of carbon steel beads, for experiments with S19, with filtered S19 and with bronopol dissolved in defined medium. This indicated that the high corrosion rate found for S19 was due to its high bronopol concentration. The corrosion rate of coiled tubing coupons also increased linearly with bronopol concentration as determined by electrochemical methods. Profilometry measurements also showed formation of multiple pits on the surface of coiled tubing coupon with an average pit depth of 60 μm after 1 week of incubation with 1 mM bronopol. At the recommended dosage of 100 ppm the corrosiveness of bronopol towards carbon steel beads was modest (0.011 mm/yr). Higher concentrations, resulting if biocide is added repeatedly as commonly done in shale gas operations, are more corrosive and should be avoided. Overdosing may be avoided by assaying the presence of residual biocide by HPLC, rather than by assaying the presence of residual surviving bacteria. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT Current models for unconformity-associated uranium deposits predict fluid flow and ore deposition along reactivated faults in >1.76 Ga basement beneath Mesoproterozoic siliciclastic basins. In frontier regions such as the Thelon Basin in the Kivalliq region of Nunavut, little is known about the sub-basin distribution of units and structures, making exploration targeting very tenuous. We constructed a geological map of the basement beneath the unconformity by extrapolating exposed features into the subsurface. The new map is constrained by detailed geological, geophysical, and rock property observations of outcrops adjacent to the basin and by aeromagnetic and gravity data over the geophysically transparent sedimentary basin. From rock property measurements, it is clear that the diverse magnetic and density characteristics of major rock packages provide quantitative three-dimensional constraints. Gravity profiles forward modelled in four cross sections define broad synforms of the Amer Belt and Archean volcanic rocks that are consistent with the structural style outside the basin. Major lithotectonic entities beneath the unconformity include: supracrustal rocks of the Archean Woodburn Lake group and Marjorie Hills meta sedimentary gneiss and associated mixed granitoid and amphibolitic gneiss; the Amer Mylonite Zone and inferred mafic intrusions oriented parallel and sub-parallel; other igneous intrusions of 2.6 Ga, 1.83 Ga, and 1.75 Ga vintage; and the <2.3 Ga to >1.84 Ga Amer Group. Four main brittle regional fault arrays (040°-060°, 075°-90°, 120°, and 150°) controlled development and preservation of the basin. The reactivated intersections of such faults along fertile basement units such as the Rumble assemblage, Marjorie Hills assemblage, Nueltin igneous rocks, and Pitz formation are the best targets for uranium exploration. [ABSTRACT FROM AUTHOR]

Seasonal distribution of adult Atlantic sturgeon was examined using pop-up satellite archival tags (PSATs) and ultrasonic transmitters deployed in the Saint John River, New Brunswick, Canada. Seven MK10 PSATs programmed for release in June 2012 and seven MiniPAT PSATs programmed for release in February and April 2013 were deployed in August 2011 and 2012, respectively. Eleven of 14 PSATs surfaced and transmitted depth and temperature data archived for the duration of their deployment (121–302 days). Among these eleven PSATs, five were recovered and 15-sec archival data was downloaded. Following exit from the Saint John River in the fall, tagged fish occupied a mean monthly depth of 76.3–81.6 m at temperatures as low as 4.9˚C throughout the winter before returning to shallower areas in the spring. The majority of ultrasonic detections occurred in the Bay of Fundy, but fish were detected as far as Riviere Saint-Jean, Quebec, approximately 1500 km from the Bay of Fundy (representing long-distance migratory rates of up to 44 km/day). All PSATs were first detected in the Bay of Fundy. Tags that released in February and April were found 5–21 km offshore of the Saint John Harbour, while tags that released in June were first detected in near shore areas throughout the Bay of Fundy. The substrate at winter tag release locations (estimated from backward numerical particle-tracking experiments) consisted primarily of moraines and postglacial mud substrate with low backscatter strength, indicative of soft or smooth seabed. Based on the proximity of winter tag release locations, the consistent depths observed between fish, and previous research, it is suspected that a winter aggregation exists in the Bay of Fundy. This study expands the understanding of the marine distribution and range of Atlantic sturgeon on the east coast of Canada. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)