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The Midcontinent Rift System of North America is a ~1.1 Ga large igneous province comprising mainly flood basalts and intrusive rocks. We present new data for the Pillar Lake Volcanics and Inspiration Sill from the northern edge of the Midcontinent Rift in the northwestern Nipigon Embayment. The Pillar Lake Volcanics comprise a ~20-40 m thick, flat-lying sequence of mafic pillowed and massive flows, pillowed flow breccia, and hyaloclastite breccia. They are characterized by [SiO.sub.2] of 52-54 wt%, [TiO.sub.2] of 1.2-1.3 wt%, and [K.sub.2]O of 0.9-1.1 wt%. They are light rare earth element (LREE) enriched, with La/Smn of 3.0-4.4 with fractionated heavy rare earth elements (HREE) (Gd/[Yb.sub.n] = 1.4-1.7). The Inspiration diabase sill is < 50 m thick and is in direct contact with the underlying Pillar Lake Volcanics. Baddeleyite and zircon data from the Inspiration Sill yield a combined U-Pb upper intercept age of 1105.6 [+ or -] 1.6 Ma. The Inspiration Sill is characterized by uniform [SiO.sub.2] of 52-53 wt%, [TiO.sub.2] of 1.1-1.2 wt%, and [K.sub.2]O of 0.9-1.2 wt%. Inspiration Sill samples are LREE enriched with La/[Sm.sub.n] of 3.2-3.3 and fractionated HREE (Gd/[Yb.sub.n] = 1.6). The Pillar Lake Volcanics are at least 1120 Ma, and perhaps as old as 1130 Ma, and represent an early, thin, and restricted mafic volcanic sequence, largely preserved below the younger Inspiration Sill. The Pillar Lake Volcanics and Inspiration Sill display a marked geochemical similarity, suggesting that they may represent magmatism associated with the earliest stages of Midcontinent rifting. Key words: Pillar Lake Volcanics, Inspiration Sill, Midcontinent Rift, geochemistry, geochronology. Le rift mediocontinental nord-americain est une grande province ignee de ~1,1 Ga comptant de nombreux basaltes de plateau et roches intrusives. Nous presentons de nouvelles donnees sur les roches volcaniques du lac Pillar et le filon-couche d' Inspiration, a la limite nord du rift mediocontinental dans le nord-ouest de l'echancrure de Nipigon. Les roches volcaniques du lac Pillar consistent en une sequence horizontale de ~20-40 m d'epaisseur de coulees mafiques massives et a coussins, de breches de coulees a coussins et de breches de hyalocastites. Elles sont caracterisees par des teneurs en SiO2 de 52-54 % poids, en [TiO.sub.2] de 1,2-1,3 % poids et en [K.sub.2]O de 0,9-1,1 % poids. Elles sont enrichies en terres rares legeres et presentent des rapports La/Smn allant de 3,0-4,4 et des terres rares lourdes fractionnees (Gd/[Yb.sub.n] = 1,4-1,7). Le filoncouche diabasique d'Inspiration fait < 50 m d' epaisseur et est en contact direct avec les roches volcaniques du lac Pillar sous-jacentes. Des donnees sur de la baddeleyite et du zircon du filon-couche d' Inspiration produisent un age U-Pb d'intersection superieure de 1105,6 [+ or -] 1,6 Ma. Le filon-couche d' Inspiration est caracterise par des teneurs uniformes en [SiO.sub.2] de 52-53 % poids, en [TiO.sub.2] de 1,1 a 1,2 % poids et en [K.sub.2]O de 0,9-1,2 % poids. Les echantillons du filon-couche d' Inspiration sont enrichis en terres rares legeres et presentent des rapports La/Smn allant de 3,2-3,3 et des terres rares lourdes fractionnees (Gd/[Yb.sub.n] = 1,6). L' age des roches volcaniques du lac Pillar est d'au moins 1120 Ma, pouvant possiblement atteindre 1130 Ma, et ces roches representent une sequence volcanique mafique precoce mince et de faible etendue, principalement preservee sous le filon-couche d'Inspiration, plus jeune. Les roches volcaniques du lac Pillar et le filon-couche d'Inspiration presentent une similitude geochimique marquee qui donne a penser qu'ils pourraient representer un magmatisme associe aux toutes premieres phases du rifting mediocontinental. [Traduit par la Redaction] Mots-cles: roches volcaniques du lac Pillar, filon-couche d' Inspiration, rift mediocontinental, geochimie, geochronologie., Introduction The Midcontinent Rift System (MRS) of North America comprises ~1500 000 km (3) of flood basalts, flows, and intrusive rocks emplaced in the Lake Superior region during the Mesoproterozoic [...]

ABSTRACT The Lower Coverdale intrusion near Moncton, New Brunswick, has been intersected in drill holes at depths of 100-200 m below unconformably overlying Carboniferous sandstone, conglomerate and, locally, limestone of [...]

The provenance of sedimentary strata that accumulate in foreland basins record the growth and denudation of the adjacent orogen. We use U-Pb geochronology of detrital zircon and monazite, Sm-Nd isotope geochemistry, trace- and rare earth element geochemistry, and petrographic data from synorogenic clastic sedimentary rocks in the Cordilleran foreland basin of southwestern Alberta to provide new perspectives on the evolution of the orogen. Foreland basin clastic rocks comprise three major pulses of sediment delivery: (1) upper Fernie Formation-Kootenay Group (154-142 Ma), (2) Blairmore Group (115-103Ma), and (3) Milk River Group-Porcupine Hills Formation (78-58 Ma). Nd isotope data are dominated by [[epsilon].sub.Nd] values of -7 to -12, interpreted to represent a well-mixed provenance from Devonian through Triassic strata and subordinate contributions from thrust-imbricated pre-Devonian strata of the Cordilleran miogeocline. Significant deviations to less negative (more juvenile) values between -5 and +1 represent periods when the foreland was flooded by juvenile detritus from oceanic arc sources such as Quesnel terrane and from syndepositional continental magmatic arcs of mid- and Late Cretaceous ages. Detrital zircon and monazite from the Fernie-Kootenay clastic pulse (pulse 1) indicate derivation from Triassic-Ordovician sandstones imbricated within the thrust-and-fold belt, consistent with the Nd tracer results and petrography. U-Pb zircon ages from the Blairmore Group (pulse 2) confirm a provenance from Triassic and Jurassic arc rocks of Quesnel terrane with only minor contributions from older miogeoclinal rocks; they also record the presence of syndepositional magmatic material. The upper part of the Blairmore Group shows a transition to less juvenile Nd isotopic signatures and the reappearance of detrital zircons of miogeoclinal derivation. A similar pattern occurs in the Milk River-Porcupine interval (pulse 3) with juvenile material occurring early in the sequence, accompanied by zircon grains from syndepositional volcanic sources and by more continental material in the upper part of the sequence. Pulse 1 records the erosion of thrust-imbricated miogeoclinal rocks during the creation and erosion of the foreland thrust-and-fold belt with no detectable material derived from the deeper parts of the hinterland. A significant unconformity of ~27 m.y. duration led to redistribution of the foreland basin fill and erosion of the adjacent thrust-and-fold belt and corresponds to a period of magmatic and tectonic quiescence in the southern Canadian Cordillera. Renewed contraction within the erosionally modified thrust wedge led to development of out-of-sequence thrust structures which allowed juvenile terranes (Quesnel terrane) to become the dominant source for tbreland (pulse 2) to the exclusion of miogeoclinal material. Reappearance of the miogeoclinal signature in upper pulse 2 is interpreted to record eastward propagation of the thrust-and-fold belt into miogeoclinal strata. The third pulse of sediment records significant input of windblown ash from juvenile sources in the Coast Belt mixed with bedload components derived from more local sources in the eastern Cordillera. The youngest deposits in the basin (ca. 58 Ma) are characterized by a cosmopolitan provenance that likely records cannibalization of older parts of the foreland as previously deposited foreland strata became important components of the thrust wedge. Keywords: Cordillera, orogen, foreland, provenance, tectonics, isotopes.

Bryn yr Hen Bobl (NGR SH 5185 6900) is a large Neolithic chambered cairn lying in pasture and parkland on the west side of the Plas Newydd estate, Anglesey. The [...]

Abstract: Aim/Purpose: This phenomenological investigation sought to describe how counsellors (n = 9), residing in Scotland, experience altruistic caring in their personal and professional lives. This study is an extension of a research line of qualitative studies focused on a model of altruism development. The purpose is to focus on practising counsellors’ common experiences as they relate to altruistic caring and to describe the phenomenon that occurs within the context of the Altruism Development Model (ADM) (Curry, Smith & Robinson, 2009). Methodology: This study is a phenomenological research design. The research team obtained permission from the institutional review board (IRB) to conduct in‐depth interviews and record observations. A diverse group of practising counsellors, living in Scotland, were interviewed. Moustaka's (1994) transcendental approach was used to analyse the data, to provide a new perspective from previous studies. More specifically, the research team conducted horizontalisation and developed structural and textural descriptions to describe the phenomenon. Findings: The findings provide support for the ADM. The textural description of participants’ experiences of altruism is that their experiences are complex, and sometimes conflicting. The structural description of participants’ experiences of altruism is that it is a part of themselves. Counsellors in Scotland experience altruism as part of everyday life and view it as an expectation, and counsellors in Scotland recognise that altruism can include wellness and self‐care and that these are important to be an effective counsellor. Research Limitations: All the participants were members of a professional organisation and self‐selected to be a part of the study. Additionally, the researchers’ culture may have influenced the way they analysed the findings. Implications: Altruism is a socially learned attribute, and it is highly regarded in Scottish culture. Therefore, counsellors may want to explore the influence of culture within a client's life, in relation to altruism. Additionally, exploring the constructs of altruism and self‐care for clients may be an important step in a holistic assessment. [ABSTRACT FROM AUTHOR]

High-quality U–Pb (Isotope Dilution-Thermal Ionisation Mass Spectrometry; ID-TIMS) baddeleyite ages were obtained for the Salto do Céu (SC) gabbroic sill (1439 ± 4 Ma) and Nova Lacerda mafic dyke swarm (1387 ± 17 Ma) located ca. 150 km apart in the Jauru terrane (Paleo- to Mesoproterozoic) – SW Amazonia. From a geodynamic perspective, the new ages mark widespread Mesoproterozoic extensional tectonics and associated magmatism (e.g. dolerite dykes and rapakivi suites) in a growing continental margin. The SC sill is coeval with the nearby Rio Branco anorogenic rapakivi granite. Intermittent extensional tectonics (1.44 and 1.39 Ga) is widespread in the central and northern portions of the Amazonian Craton, given by co-magmatic charnockites and rapakivi granites, and mafic–ultramafic complexes. On a global scale, this activity may be coeval with a major intra-continental-related igneous event in Laurentia and Fennoscandia, as well as with mafic dykes in NW West African Craton. This suggests large igneous province (LIP)-scale magmatism. A further aspect is that the 1.4 Ga magmatism is age-equivalent with convergent-margin processes (Alto Guaporé orogen and the related Rio Alegre oceanic remnant) that evolved outboard the active margin of the proto-Amazonian Craton. This may represent a coincidence in time between intraplate rifting, LIP magmatism (plume related) and subduction. Other causal mechanisms are also considered such as pulses of back-arc extension behind the accreting arcs. Our data provide new clues as to the longevity of the Columbia (or Nuna) supercontinent, and are consistent with previously published paleomagnetic poles from Mesoproterozoic intraplate magmatism in Amazonia, Laurentia and Baltica (South America-Baltica model). [ABSTRACT FROM PUBLISHER]