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A review of information from Statistics Canada and the Council of Chairs of Canadian Earth Science Departments examined the geoscience workforce in Canada over the last two decades through economic cycles and environmental transitions. After a period of growth in Canada (2006 to 2011), geoscientist numbers in the labour market declined by 11% from 2011 to 2021, whereas the numbers of geological engineers grew by 56%. The combined total for both classifications remained fairly constant. By Census 2021 Canada had about 11,000 geoscientists (including oceanographers) and about 4,000 geological engineers. Professional, scientific and technical services, mining, quarrying and oil and gas extraction are the major employment sectors. Employment for geoscientists is cyclical and tied to economic and commodity-price cycles. Alberta experienced the largest decline in geoscientist numbers (-34.5%), correlated with reduced oil- and gas-development investments from 2014 to 2020. Growth in other provinces (e.g. British Columbia, Ontario) partly offset the decline in Alberta. Nearly 30% of geoscientists are immigrants, as defined by their countries of birth. The university education supply pipeline shows that enrolment in core geoscience and geological engineering undergraduate programs dropped significantly (50% decline from 2015 to 2022) with a corresponding drop in graduations. However, enrolments in Earth Science programs related to aspects beyond core geoscience and geological engineering (e.g. environmental science in its broadest sense) tripled between 2007 and 2022. If these trends continue, the majority of students will be enrolled in these associated programs rather than graduating with core geoscience knowledge and skills. There is a need for more comprehensive and up-to-date data to represent the characteristics of the geoscience workforce accurately and to inform policy decisions and individual career choices. The current situation implies that shortages of qualified geoscience professionals could develop in future years.

Une traduction française du North American Stratigraphic Code, publiée en 1986, concerne le Code de 1983, qui, après complète révision, donna le Code de 2005, lui-même mis formellement à jour au cours des années et republié en 2021*. Nous présentons ici une nouvelle version française du Code. Elle inclut également les révisions formelles des Articles 7 et 20 publiées dans deux rapports officiels (2023 et 2024, respectivement). À la demande de la North American Commission on Stratigraphic Nomenclature (NACSN) nous présentons une nouvelle version française du North American Stratigraphic Code pour le bénéfice des géologues de langue française dans la communauté internationale.Le North American Stratigraphic Code avait été traduit en français par le Ministère de l’Energie et des Ressources du Québec et publié en 1986. Cette traduction reste disponible, mais elle ne reflète pas les changements conceptuels qui ont guidé les révisions successives du Code et l’expansion de son contenu, conduisant ainsi à la publication du Code de 2005. Plusieurs articles de ce Code ont été formellement émendés depuis afin de refléter l’évolution plus récente des concepts stratigraphiques. Ces émendations, publiées dans Stratigraphy, le journal scientifique de la NACSN, ont été intégrées dans une version récente, légèrement révisée du Code, et publiée en 2021. Près de quarante ans se sont donc écoulés entre la traduction française de 1986 et le code actuel, ce qui justifie amplement notre nouvelle version.La traduction que nous proposons est aussi fidèle que possible au texte anglais, ainsi que l’a demandé la NACSN. Toutefois, il n’a pas toujours été possible d’honorer ce souhait et en même temps de satisfaire les règles de la syntaxe et grammaire françaises. Nous espérons avoir concilié les deux langages tout en respectant la signification du texte anglais. Nous nous sommes éloignées de ce texte dans deux cas importants. Nous avons traduit le terme « sequence », utilisé dans tout le texte anglais, par « succession » parce que « sequence » a acquis un usage commun et précis en stratigraphie séquentielle, alors que « succession » reste un terme générique. Par ailleurs, nous avons traduit « rock unit » et « body of rock », mots composés qui décrivent l’unité de base de la nomenclature stratigraphique dans le Code lui-même, par « ensemble de terrains », une expression qui, nous le pensons, exprime plus clairement et efficacement le sens de « rock unit » et « body of rock » que ne le feraient des idiomes tels que « unité de roche », « unité rocheuse », ou « corps rocheux ».Plusieurs articles du Code de 2021 ont été formellement émendés au cours des deux dernières années, et leurs révisions formelles ont fait l’objet des Rapports 15 et 16. Nous avons incorporé nos versions des textes émendés des Articles 20, 61 et 62 qui formalisent les unités chimiostratigraphiques dans le Rapport 15. Le Rapport 16, qui concerne le respect des traditions culturelles des peuples vivant dans des régions d’importance géologique, comprend une traduction en français. Cette dernière fait appel à la traduction de 1986 pour les Articles 7 et 20 alors que la traduction des émendations de ces articles a été effectuée par le Bureau de la Traduction, Services publics et Approvisionnement Canada. Nous avions déjà incorporé les Articles 7 et 20 dans notre version quand le Rapport 16 a été soumise pour publication, de sorte que nous utilisons nos textes dans un souci d’homogénéité stylistique. Pour la même raison nous avons modifié les textes émendés. *North American Commission on Stratigraphic Nomenclature, 2021, North American Stratigraphic Code: Stratigraphy, v. 18, p. 153–204.

“Geosciences are important for humanity” is the central message of a model presented to promote the geosciences as essential to the development of Canada and the world. Components of the geosciences directly or indirectly address all 17 UN Sustainable Development Goals, and geoscientific knowledge is essential in efforts to address climate change. Despite this broad relevance, many Canadians remain unaware of the importance of the geosciences, partly because the discipline is not consistently offered as a standalone high school course in all provinces and territories. The number of students entering undergraduate geology major programs declined by over 40% between 2015 and 2022, and this creates challenges within Canada’s workforce. Currently, gaps in the workforce are filled through immigration, but the federal government is now starting to limit immigration. The seven components of the proposed model include: public engagement to promote the geosciences in varied settings; engagement with politicians and policy makers; engagement with resource and other industries; development and implementation of strategic plans to promote improved awareness of the geosciences; development of public education, outreach and communication programs; promotion of courses and engagement programs at post-secondary institutions; and coordination with geoscience societies and geological surveys. Hosting the International Geological Congress (IGC) 2028 could unite the Canadian geoscience community by strengthening connections between academic geoscientists and government, advocating for a Canadian Research Chair related to geoscience education and outreach, developing an inventory for geoscience education and outreach programs, and exploring creative ways to develop standalone geoscience courses in high school. If all Canadian geoscientists use the model components to emphasize the importance of the geosciences to humanity, we can collectively work towards better public understanding of the relevance of the geosciences to most aspects of life in Canada and improve the future of our vital discipline.

university professor, and scientific researcher passed away peacefully on October 16, 2024 at

Phenocrysts in porphyritic lava flows are generally considered to have grown under conditions of slow magma cooling within source reservoirs at depth. The matrix (i.e. groundmass) surrounding the phenocrysts is assumed to form under rapid cooling conditions subsequent to eruption of the residual liquids at the surface. Alternatively, it has been demonstrated experimentally that phenocrysts could grow subaerially in basaltic lavas cooled at constant, linear rates. It has been suggested this mechanism could explain the correlation of porphyritic textures with unusually thick canyon-filling flows of Columbia River Basalt. Field and petrographic data supports intratelluric nucleation and growth of plagioclase phenocrysts in three lavas of the Columbia River Basalt Group (CRBG). The distinction is important because the typical basaltic phenocryst paragenesis (plagioclase, followed by olivine, then augite), if produced under surface conditions, cannot be used to test fractional crystallization models in magma reservoirs of the Columbia River Basalt Group or any other lavas. Ideally, to test the hypotheses of subaerial vs. intratelluric (subsurface) growth of phenocrysts, both intrusive (i.e. dykes) and extrusive samples crystallized from the same liquid need to be examined to compare sizes and abundances of phenocrysts. If phenocryst growth occurs only subaerially, then a lava flow should contain more phenocrysts than its intrusive counterpart. In the case of nucleation and growth in both a dyke and its flow, the flow still would contain more phenocrysts due to grains formed in the dyke being added to those formed in the flow. Detailed modal and grain size data were collected for three dyke-flow pairs of CRBG by the author and provide an excellent opportunity to compare intrusive and extrusive textures. These findings along with XRF major and trace element data indicate that the phenocrysts in these lavas must have grown within the magma reservoir and not at the surface. A model is proposed that explains the variation of phenocryst distribution laterally within a lava as an interplay of variations of magma flow and the underlying paleo-topography.

The northern Appalachian orogen played a pivotal role in early geological studies of mountain belts. Its 100-year global influence as the “type area” for the Hall-Dana geosynclinal theory aptly changed focus with Tuzo Wilson’s classic 1966 paper that posed (and answered) the question “Did the Atlantic Close and Then Re-open?” and led to the modern view of global tectonics based on the “Wilson Cycle”. In retrospect, these early ideas about mountain-building were much hindered by lack of factual details. The 1978 map of the Appalachian Orogen compiled and hand-drawn by Harold Williams and his students was and remains an outstanding example of geological artwork, although the actual complexity of the orogen that it depicts was barely imagined. However, the tectonic elements and along-orogen correlations that it established still form the essence of our current models, but now supported by an abundance of geological information collected steadily during the last decades of the 20th century and then accelerated by technological advances during the past 25 years. Examples include the Global Positioning System to provide accurate locations, enhanced geochemical and geophysical methods, computers and the Internet in general, and the development of accurate and precise absolute dating techniques, especially U–Pb dating of zircon. Appalachian studies now cover a spectrum from small areas investigated in detail to orogen-wide and global-scale interpretations that track Appalachian components back to their origins. We now know orders of magnitude more about the orogen than anyone could have imagined in 1978. Not surprisingly all that new knowledge has resolved many of the questions that were being asked in the 1970s but also not surprisingly, many more questions have arisen. It seems that every new map, new interpretation, or new model challenges us with new questions. It appears unlikely that geoscientists will ever be able to sit back and say “All done. We understand everything”.

This paper reviews the five Ws (Why, What, Who, When, and Where) of carbon capture and storage in southwestern Ontario. This area is home to nearly one quarter of Canada’s population and approximately three-quarters of one million people work in the manufacturing sector. Fifteen of the province’s top 20 CO2 emission point sources are in this area. The industries responsible for these emissions include steel mills, refineries and petrochemical plants, and cement plants. These industries are part of the hard-to-abate sector, in that CO2 is used or generated as an integral part of the industrial process. As such, eliminating or even reducing emissions from these industries is a difficult task. Carbon capture and storage (CCS) projects aim to sequester that gas in sedimentary basins over periods exceeding several thousand years. To this end, deeply buried (> 800 m) porous and permeable rocks (a repository) must be overlain by impermeable rocks that act as a seal, preventing the upward migration of CO2 into the atmosphere. The possibility that injection activities could trigger seismicity is but one of the additional considerations. When operational, CCS projects have a negative carbon footprint and the desirability of developing and using this technology has been established for over 20 years. True CCS projects differ from carbon capture, utilization, and storage (CCUS) projects in that the former are only designed with sequestration in mind. One type of CCUS project involves using CO2 for enhanced oil recovery (EOR) and this technology has been employed for several decades. Cambrian sandstones are the most suitable injection targets for CCS in southwestern Ontario because previous oil and gas drilling has shown the rocks to have the necessary characteristics. They are buried below 800 m, can be tens of metres thick, and have adequate porosity and permeability. However, the Cambrian section is lithologically and stratigraphically heterogeneous and oil, gas, and brine can all be present in the pore space. The extent to which this complexity will affect CO2 injection has not yet been evaluated.