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Unconformity‐related uranium (URU) deposits in the Athabasca Basin, Canada, include the highest grade, large tonnage deposits in the world. Recent studies of the Patterson Lake corridor uranium deposits suggest a deep heat source enhances hydrothermal fluid flow and incursion of basinal brines along brittlely reactivated ductile shear zones. However, the spatial extent of the ore systems and lower crustal features capable of driving the hydrothermal cells remained largely unresolved. Three‐dimensional electrical conductivity models derived from inversion of magnetotelluric data and coincident gravity modeling identified a voluminous conductivity anomaly and corresponding gravity low related to a belt of high‐heat producing intrusions that dips below the deposit. Shallow conductive bodies are identified below the deposits and similarly prospective corridors. The volume and location of the intrusive bodies may have provided a source of radiogenic heat that helped drive remobilization of fluids along reactivated structures, redefining the spatial extent of URU systems. Plain Language Summary: The western Athabasca Basin, straddling the border of Saskatchewan and Alberta in Canada, is home to some of the highest‐grade, large tonnage uranium deposits in the world. Recent studies have suggested a spatial connection between uranium ore systems that are found near the earth's surface and geological processes occurring deep within the crust. However, the processes connecting the lower crust to these shallow deposits is poorly understood. This study used 3D models created from magnetotelluric data, a passive a geophysical technique that measures the earth's natural electric and magnetic fields, to image the earth from surface to a depth of 40 km. We identified a voluminous igneous intrusion that extends from the surface to great depths in the earth's crust. We propose that this intrusion may have contributed to the uranium endowment of the basin, and that radiogenic heat from the large igneous body helped circulate uranium‐bearing fluids through the shallow crust along reactivated geologic structures. The modeling, when combined with other geoscientific datasets, showcases the role of high‐heat producing granitic intrusions in driving the hydrothermal fluid cells that formed the deposits. Key Points: Integrated resistivity—gravity modeling over the Arrow uranium deposit in CanadaMagnetotelluric inversion images deep‐seated thermal source and fluid pathways that formed some of the highest‐grade uranium depositsHolistic ore system model illustrates relationship between crustal ore system and lower crustal resistivity anomalies [ABSTRACT FROM AUTHOR]

Introduction: Improving health services integration through primary health care (PHC) teams for patients with chronic conditions is essential to address their complex health needs and facilitate better health outcomes. The objective of this study was to explore if and how patients, family members, and caregivers were engaged or wanted to be engaged in developing, implementing and evaluating health policies related to PHC teams. This patient‐oriented research was carried out in three provinces across Canada: British Columbia, Alberta and Ontario. Methods: A total of 29 semi‐structured interviews with patients were conducted across the three provinces and data were analysed using thematic analysis. Results: Three key themes were identified: motivation for policy engagement, experiences with policy engagement and barriers to engagement in policy. The majority of participants in the study wanted to be engaged in policy processes and advocate for integrated care through PHC teams. Barriers to patient engagement in policy, such as lack of opportunities for engagement, power imbalances, tokenism, lack of accessibility of engagement opportunities and experiences of racism and discrimination were also identified. Conclusion: This study increases the understanding of patient, family member, and caregiver engagement in policy related to PHC team integration and the barriers that currently exist in this engagement process. This information can be used to guide decision‐makers on how to improve the delivery of integrated health services through PHC teams and enhance patient, family member, and caregiver engagement in PHC policy. Patient or Public Contribution: We would like to acknowledge the contributions of our patient partners, Brenda Jagroop and Judy Birdsell, who assisted with developing and pilot testing the interview guide. Judy Birdsell also assisted with the preparation of this manuscript. This study also engaged patients, family members, and caregivers to share their experiences with engagement in PHC policy. [ABSTRACT FROM AUTHOR]

Several lacustrine carbonate beds, each a metre‐thick interval of densely packed Mn‐rich sideritic micro‐spherulites or Mn‐rich ferroan calcite micro‐spherulites, are recorded for the first time within strata of the Lower Cretaceous McMurray Formation of the northern Athabasca Oil Sands deposit, western Canada. A lower McMurray lacustrine carbonate deposit is characterised by a metre‐thick bed fabric of Mn‐rich siderite micro‐spherulites. The middle and upper interval McMurray beds developed fabrics of Mn2+‐rich ferroan calcite micro‐spherulites. These carbonate beds represent saline lacustrine depositional environments that resulted from the lake bottom sediments ingressed from below by Mn2+‐Fe2+‐rich carbonate‐saturated brines. These up‐section migrations of Devonian formation water were sourced from dissolution trends developed in limestone and halite‐anhydrite beds of the underlying Devonian Prairie Evaporite during Cordilleran deformation of the Alberta Basin foreland. These brines ascended to the overlying McMurray Formation sediments along dissolution‐collapse structures such as breccia pipes, sinkholes and margins of differentially subsided Upper Devonian fault blocks. The up‐section migration of a sulphate‐saturated Fe2+ and Mn2+‐rich brine resulted in the ingress of a lower McMurray lacustrine bottom sediment at a site associated with the development of a peat mire terrain. Microbial redox of the lake bottom sediment resulted in a carbonate bed of micro‐spherulitic fabrics of Mn‐rich siderite interwoven with pyrite laminae. Subsequent salt dissolution events and up‐section migrations of Devonian brine during deposition of the middle and upper McMurray intervals resulted in similar carbonate‐saturated but sulphate‐poor chemistry. These saline flows also ingressed lacustrine bottom sediments below, and resulted in limestone beds of densely packed spherulitic fabrics of Mn‐ferroan calcite, not siderite. These deposits provide insight into largely unknown dispositions of voluminous brine resulting from salt dissolution trends below the Athabasca Oil Sands and further our understanding of controversial McMurray depositional processes. [ABSTRACT FROM AUTHOR]

The McMurray Formation in McMurray Depocentre, Canada, is typically subdivided into stratigraphic units based on regionally mappable marine mudstones, the bases of which define flooding surfaces (bottom to top: Lower McMurray, C2, C1, B2, B1, A2, A1 depositional unit). However, the McMurray Formation comprises a variety of palaeoenvironments, with the north‐eastern Firebag Tributary hosting significant delta‐plain deposits in the Lower McMurray and B1 depositional units. Facies analysis of 60 cores and 4763 wireline logs was used to resolve the palaeoshoreline trajectory and stratigraphic architecture in Firebag Tributary. Of 14 identified facies, three delta‐plain facies reveal: (1) eluviated palaeosols, interpreted as shrublands and woodlands formed during base‐level fall; (2) gleyed palaeosols, interpreted as tidal marshes; and (3) coals formed in coastal mires, the two latter facies are interpreted to accumulate during base‐level rise. Eluviated palaeosols occur below the Lower McMurray coal seam, implying valley incision and a maximum regressive surface. Gleyed palaeosols underlying the coal seam atop the B1 depositional unit do not record base‐level fall. Wetting‐upward coals overlying either palaeosol facies indicate base‐level rise (i.e. major flooding surface). B1 depositional unit coals and gleyed palaeosols are overlain by shallow‐marine facies or are eroded by wave ravinement during transgression. Consequently, the tops of coals or gleyed palaeosols correlate to the bases of regional marine mudstones elsewhere in McMurray Depocentre. Stratigraphic cross sections showcase palaeoshoreline regression and transgression. During the Lower McMurray and B1 depositional units, widespread coals and palaeosols indicate the palaeoshoreline resided near the western edge of Firebag Tributary. Regression during C2 through B2 depositional units and A2 and A1 depositional units resulted in palaeoshorelines near the Alberta–Saskatchewan border. To complement a previously dated Lower McMurray ash (121.39 ± 0.2 Ma), a new high‐confidence maximum depositional age from ash in the B1 coal seam (115.09 ± 0.16 Ma) allows an estimate to be made of depositional duration, indicating depositional units represent ca 0.16 Myr. [ABSTRACT FROM AUTHOR]

Meteorite impact‐induced mobilization of a volcanic ash tuff resulting in 100s of m long lithified clastic dikes is a novel mechanism in the geologic record. The Paleogene Eagle Butte impact event in southeastern Alberta, western Canada, resulted in a 10–17 km diameter central peak crater, now partially eroded and buried without expression at the surface. Impact shock waves, degraded to elastic waves, mobilized sediment 10s of km beyond the crater and resulted in a cluster of 100s of m long, 10–20 cm thick, dikes consisting of volcanic ash. It is not well understood how effective meteorite impact‐induced waves would be as triggers for sediment mobilization at areas 10s of km distant from an impact crater. Emplacement of the Manyberries dike cluster provides insight into this issue and confirms that shock waves, degraded to elastic waves, can indeed liquefy and mobilize sediments at distances as much as 5 crater radii beyond an impact site. These impact‐induced waves triggered liquefaction and mobilization of a shallowly buried Campanian‐Maastrichtian deposit of volcanic ash and injected the tuff sediment along impact‐induced faults. The lithification of the dike tuff, consisting of the cristobalite–tridymite groundmass, resulted from partial dissolution of glass shards and precipitation of opaline cement. These weathering resistant dikes of indurated tuff sediment extend for as much as 800 m on recessive Campanian‐Maastrichtian shale ridges of the badlands topography. [ABSTRACT FROM AUTHOR]