bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation Into the Relationship Between Adolescents’ Perceived and Actual Fundamental Movement Skills and Physical Activity
Authors: McGrane Bronagh , Powell Danielle , Belton Sarahjane , Issartel Johann
Published: October 2017

Objectives: To explore the relationship between fundamental movement skill (FMS) competence, perceived FMS competence, and physical activity (PA) in adolescents. Methods: The Test of Gross Motor Development (TGMD), the TGMD 2nd Edition (TGMD-2), and the Victorian Skills manual were used to assess FMS competence (locomotor, object control, and stability). The Physical Self Confidence scale was used to assess perceived FMS competence (locomotor, object control, and stability). Moderate-to-vigorous intensity PA (MVPA) was measured via accelerometry. Multi-level modelling analyses was used to examine (i) actual FMS as the predictor and perceived FMS as the outcome, (ii) perceived FMS as the predictor and MVPA as the outcome, and (iii) actual FMS as the predictor and MVPA as the outcome. All analyses were completed for each subtest of FMS (locomotor, object control, and stability). Results: A total of 584 adolescents (boys n = 278) aged 12.82–15.25 years (M = 13.78, SD = .42) participated in this study. Actual stability was associated with perceived stability (p < .01) and MVPA (p < .05) in boys. This was not found true for girls; however, actual locomotor skills were associated with MVPA (p ≤ .05). Boys scored significantly higher than girls for FMS proficiency, perceived FMS, and MVPA (p < .05). Discussion: Gender differences may exist due to cultural gender differences in sport participation norms. Considering the magnitude of physical and psychological changes occurring during adolescence, it is recommended to track young people over time to better understand the relationship between perceived and actual FMS, as well as PA participation.
Effectiveness of Salted Ice Bag Versus Cryocompression on Decreasing Intramuscular and Skin Temperature
Authors: Ostrowski Jennifer , Purchio Angelina , Beck Maria , Leisinger JoLynn
Published: October 2017

Context: Rest, ice, compression, and elevation are commonly recommended immediately after injury. Traditionally, ice bag (IB) with elastic wrap compression has been utilized; however, recently intermittent cryocompression units are being used. Limited research has evaluated tissue temperature decreases with intermittent cryocompression units. Objective: Evaluate magnitude of muscle and skin cooling. Design: Repeated-measures counterbalanced study. Setting: University research laboratory. Patients or Other Participants: Twelve healthy college-aged participants (4 males and 8 females; age = 23.08 [1.93] y; height = 171.66 [9.47] cm; mass = 73.67 [13.46] kg; subcutaneous thickness = 0.90 [0.35] cm) without compromised circulation or injury. Intervention(s): Salted IB, GameReady (GR), and PowerPlay-ice bag (PP-ice) were applied to the posterior aspect of the nondominant calf for 30 minutes; participants underwent each treatment in counterbalanced order. Main Outcome Measure(s): Muscle temperature measured via 21-gauge catheter thermocouple; skin temperature measured via a surface thermocouple. Temperatures were recorded at baseline and during a 30-minute treatment. Correlations were evaluated between muscle and skin temperatures. Results: Nonsignificant treatment × time interaction and nonsignificant main effect of treatment for intramuscular cooling. Mean Decrease From Baseline: IB, 6.4°C (±2.8); GR, 5.4°C (±1.1); PP-ice, 4.8°C (±2.8). Nonsignificant treatment × time interaction for skin cooling (F20,200 = 1.440, P = .65, , and observed β = 0.773), but significant main effect for treatment (F10,100 = 5.279, P = .03, , and observed β = 1.00). Mean Decrease From Baseline: IB, 17.0°C; GR, 16.4°C; PP-ice, 14.6°C. No significant correlation between intramuscular and skin temperatures in any condition at any time point. No significant correlation between adipose tissue thickness and maximum temperature decrease with any modality. Conclusions: Salted IB with elastic wrap compression, GR, and PP-ice produced equivalent intramuscular temperature decreases during the treatment period.
Ricky and Stick Icky: Marijuana, Sport, and the Legibility/Illegibility of Black Masculinity
Authors: Dickerson Nikolas
Published: October 2017

In this article, I examine the ways the popular press, and two sport documentaries construct narratives of Ricky Williams’ marijuana use, early retirement, and return to the National Football League. I argue that all of the texts in question, work to produce a dominant reading of Williams, as someone who is difficult to define, and it is because of inability to put Williams’s identity into a box, that his marijuana use, “strange” personality, and early retirement is used to shoe-horn him into tropes of the bad black athlete. Nonetheless, this paper draws on Mark Anthony Neal’s concept of illegible and legible black masculinity to argue that a re-scripting of these narratives can be used to imagine alternative forms of black masculinity the emphasizes empathy, sensitivity, emotional maturity, and a rejection of domination and material wealth. This analysis is situated within the changing landscape of marijuana legislation and the racial inequity in arrest rates for marijuana.
Problematizing the Pursuit of Personal Development and Performance Success: An Autoethnography of a Canadian Elite Youth Ice Hockey Coach
Authors: Preston Cassidy , Fraser-Thomas Jessica
Published: October 2017

Performance success and positive development are goals of youth sport coaching that need not but often do find themselves in conflict with each other, yet there is a dearth of research that has inquired into the tensions between these 2 goals for sport coaches. Adopting an autoethnographic research design, this study explored the first author’s coaching experiences with a focus on his attempts to facilitate players’ personal development and the team’s performance success in a Canadian elite minor ice hockey context. Framed in a positive-youth-development approach, the first author’s philosophy and behaviors were informed by key tenants of achievement goal theory and self-determination theory. Three key areas were problematized: pursuing personal development and performance success, creating a task-oriented environment, and implementing autonomy-supportive behaviors. Practical implications for elite youth coaches and coach educations programs are discussed.
SwiftandNuSTARobservations of GW170817: Detection of a blue kilonova
Authors: Evans P. A. , Cenko S. B. , Kennea J. A. , Emery S. W. K. , Kuin N. P. M. , Korobkin O. , Wollaeger R. T. , Fryer C. L. , Madsen K. K. , Harrison F. A. , Xu Y. , Nakar E. , Hotokezaka K. , Lien A. , Campana S. , Oates S. R. , Troja E. , Breeveld A. A. , Marshall F. E. , Barthelmy S. D. , Beardmore A. P. , Burrows D. N. , Cusumano G. , D’Aì A. , D’Avanzo P. , D’Elia V. , de Pasquale M. , Even W. P. , Fontes C. J. , Forster K. , Garcia J. , Giommi P. , Grefenstette B. , Gronwall C. , Hartmann D. H. , Heida M. , Hungerford A. L. , Kasliwal M. M. , Krimm H. A. , Levan A. J. , Malesani D. , Melandri A. , Miyasaka H. , Nousek J. A. , O’Brien P. T. , Osborne J. P. , Pagani C. , Page K. L. , Palmer D. M. , Perri M. , Pike S. , Racusin J. L. , Rosswog S. , Siegel M. H. , Sakamoto T. , Sbarufatti B. , Tagliaferri G. , Tanvir N. R. , Tohuvavohu A.
Published: October 2017

GROWTH observations of GW170817

The gravitational wave event GW170817 was caused by the merger of two neutron stars (see the Introduction by Smith). In three papers, teams associated with the GROWTH (Global Relay of Observatories Watching Transients Happen) project present their observations of the event at wavelengths from x-rays to radio waves. Evanset al.used space telescopes to detect GW170817 in the ultraviolet and place limits on its x-ray flux, showing that the merger generated a hot explosion known as a blue kilonova. Hallinanet al.describe radio emissions generated as the explosion slammed into the surrounding gas within the host galaxy. Kasliwalet al.present additional observations in the optical and infrared and formulate a model for the event involving a cocoon of material expanding at close to the speed of light, matching the data at all observed wavelengths.

Science, this issue p.1565, p.1579, p.1559; see also p.1554
Light curves of the neutron star merger GW170817/SSS17a: Implications for r-process nucleosynthesis
Authors: Drout M. R. , Piro A. L. , Shappee B. J. , Kilpatrick C. D. , Simon J. D. , Contreras C. , Coulter D. A. , Foley R. J. , Siebert M. R. , Morrell N. , Boutsia K. , Di Mille F. , Holoien T. W.-S. , Kasen D. , Kollmeier J. A. , Madore B. F. , Monson A. J. , Murguia-Berthier A. , Pan Y.-C. , Prochaska J. X. , Ramirez-Ruiz E. , Rest A. , Adams C. , Alatalo K. , Bañados E. , Baughman J. , Beers T. C. , Bernstein R. A. , Bitsakis T. , Campillay A. , Hansen T. T. , Higgs C. R. , Ji A. P. , Maravelias G. , Marshall J. L. , Bidin C. Moni , Prieto J. L. , Rasmussen K. C. , Rojas-Bravo C. , Strom A. L. , Ulloa N. , Vargas-González J. , Wan Z. , Whitten D. D.
Published: October 2017

Photons from a gravitational wave event

Two neutron stars merging together generate a gravitational wave signal and have also been predicted to emit electromagnetic radiation. When the gravitational wave event GW170817 was detected, astronomers rushed to search for the source using conventional telescopes (see the Introduction by Smith). Coulter
et al.
describe how the One-Meter Two-Hemispheres (1M2H) collaboration was the first to locate the electromagnetic source. Drout
et al.
present the 1M2H measurements of its optical and infrared brightness, and Shappee
et al.
report their spectroscopy of the event, which is unlike previously detected astronomical transient sources. Kilpatrick
et al.
show how these observations can be explained by an explosion known as a kilonova, which produces large quantities of heavy elements in nuclear reactions.

Science
, this issue p.
1556
, p.
1570
, p.
1574
, p.
1583
; see also p.
1554
Electromagnetic evidence that SSS17a is the result of a binary neutron star merger
Authors: Kilpatrick C. D. , Foley R. J. , Kasen D. , Murguia-Berthier A. , Ramirez-Ruiz E. , Coulter D. A. , Drout M. R. , Piro A. L. , Shappee B. J. , Boutsia K. , Contreras C. , Di Mille F. , Madore B. F. , Morrell N. , Pan Y.-C. , Prochaska J. X. , Rest A. , Rojas-Bravo C. , Siebert M. R. , Simon J. D. , Ulloa N.
Published: October 2017

Photons from a gravitational wave event

Two neutron stars merging together generate a gravitational wave signal and have also been predicted to emit electromagnetic radiation. When the gravitational wave event GW170817 was detected, astronomers rushed to search for the source using conventional telescopes (see the Introduction by Smith). Coulter
et al.
describe how the One-Meter Two-Hemispheres (1M2H) collaboration was the first to locate the electromagnetic source. Drout
et al.
present the 1M2H measurements of its optical and infrared brightness, and Shappee
et al.
report their spectroscopy of the event, which is unlike previously detected astronomical transient sources. Kilpatrick
et al.
show how these observations can be explained by an explosion known as a kilonova, which produces large quantities of heavy elements in nuclear reactions.

Science
, this issue p.
1556
, p.
1570
, p.
1574
, p.
1583
; see also p.
1554
Degree of saturation with respect to CaCO3, CaMg(CO3)2, and CaSO4 for some thermal and mineral springs in the Southern Rocky Mountains, Alberta and British Columbia
Authors: Everdingen R. O. van
Published: October 2017

Comparison of ion-activity products and equilibrium constants for solution of CaCO3, CaMg(CO3)2, and CaSO4 indicates that water from Fairmont Hot Springs and Banff Hot Springs, and from thermal springs in British Columbia, on Lussier River, Ram Creek and near Fording Mountain, are super-saturated with respect to CaCO3 and, to a lesser extent, with respect to CaMg(CO3)2. At other springs saturation occurs after water is discharged from the springs. In the case of hot springs this is caused by the rise in pH that accompanies loss of excess CO2 and, to a lesser degree, by evaporation; cooling of the water tends to lower the degree of saturation somewhat. At cold springs, increase in water temperature after discharge increases the degree of saturation. Only near-saturation with respect to CaSO4 is indicated for Miette Hot Springs, Fairmont Hot Springs, and Fording Mountain Springs; precipitation of CaSO4 may occur here owing to evaporation of part of the water; the effect of temperature on the degree of saturation is small.
Aiyansh lava flow, British Columbia
Authors: Brown A. Sutherland
Published: October 2017

The Aiyansh alkali basalt lava flow is one of the youngest volcanic features of British Columbia, about 220 years old. It issued from a vent area (55° 7′ N, 128° 54′ W) in a narrow tributary valley of the Tseax River, flowed 14 miles (22.5 km) to the Nass Valley, and there spread out in a lava plain 6 miles (9.7 km) long, forcing the river to the northern margin of the valley. The Aiyansh flow has an area of about 15 miles2 (38.8 km2) and a volume of about 0.1 mile3 (0.455 km3).The lava flow is a single cooling unit. Its surface consists of pahoehoe, slab, and block lava in a pattern related to slope, with low slopes favoring preservation of level pahoehoe. Piping and collapse were important about the margins of the lava plain. The eruption must have terminated with a series of lava fountains and explosions in the vent area which built one main and several small cones of bombs and cinders.The Aiyansh flow is entirely a fresh black alkali basalt varying only slightly in crystallinity and texture. Holocrystalline specimens from the interior of the lava plain consist of about 50% plagioclase (An55±5), 10% olivine (Fa35), 30% pyroxene, and 10% opaques. A new chemical analysis confirms that it is a high-iron, low-magnesium, alkali basalt.
Wisconsin Environment of Interior Alaska: Pollen and Macrofossil Analysis of a 27 Meter Core from the Isabella Basin (Fairbanks, Alaska)
Authors: Matthews Jr. John V.
Published: October 2017

Information on the Wisconsin environment of interior Alaska has been obtained from study of pollen as well as the plant and animal macrofossils contained in sediments of a 27 m core at Isabella Creek, near Fairbanks, Alaska. The pollen assemblages indicate three major zones.Zone A (35 000 to 32 000 BP) represents a mid-Wisconsin interstadial during which spruce treeline was lower in elevation than at present though not nearly as low as during early and late Wisconsin time. Zone B represents a late Wisconsin interval of severe arctic climate. Forests disappeared from interior Alaska or were greatly diminished and much of the region was characterized by steppe-tundra vegetation. Steppe conditions may have been favored by rapid deposition of primary and reworked loess. Zone C shows that spruce forests and some of the associated boreal biota had returned to interior Alaska by 8500 years BP. A fluctuation of alder percentages within Zone C may result from mid-Holocene warming.Plant macrofossils from the Isabella sequence show that some species now having a boreal or taiga distribution survived the late Wisconsin of interior Alaska in a steppe-tundra environment. Other plants that were growing at Isabella during mid-Wisconsin time apparently became extinct in Alaska during the late Wisconsin.
Igneous Activity at the Birth of an Ocean Basin in Eastern Greece
Authors: Hynes Andrew
Published: October 2017

A sequence of varied igneous rocks, of Triassic age, occurs in a complex stack of thrust sheets in the Othris Mountains of eastern Greece. The igneous rocks, which are picritic basalts, diabases, keratophyric tuffs, and pillow lavas, are conformably overlain by marine sediments typical of continental margins, and tectonically overlain by several thrust sheets of ophiolitic rock. The igneous rocks are undersaturated with silica. They are similar in chemistry to igneous rocks erupted on the margins of the Red Sea, which are located on a young, accreting plate margin. The igneous rocks of the Othris Mountains are interpreted as evidence of the development of an accreting plate margin in eastern Greece in Triassic time. The ophiolites overlying them probably came from an ocean basin created at that margin.In contrast to the rocks on the margins of the Red Sea, igneous rocks on many other modern oceanic margins are saturated with silica. This contrast is tentatively related to the speed with which an accreting plate margin develops. Silica-saturated igneous rocks are probably erupted at rapidly separating continental margins, whereas silica-undersaturated igneous rocks are probably erupted in the early stages of activity at plate boundaries which begin to spread only slowly.
Paleomagnetism of Anorthosite in and around the Charlevoix Cryptoexplosion Structure, Quebec
Authors: Hargraves R. B. , Roy D. W.
Published: October 2017

Grenville anorthosite more than 20 km away from the center of the Charlevoix structure appears unaffected by the deformation, and the mean remanent vector from five sites, after demagnetization, is D = 128, I = 57, k = 49, α95 = 11; pole = 7 °N Lat., 32 °W Long., δp = 12°, δm = 16°. Progressive rotation of the NRM at three sites between 15 and 20 km of the structure center is compatible with central doming; the vectors from three sites within 15 km are anomalous, possibly reflecting modification (reversal?) of the primary vector, plus considerable tectonic rotation. The NRM at one site in 'impactite' (?), radiometrically dated at 350 m.y., is n = 3, D = 337, I = 40, k = 22, α95 = 27.
Description and origin of banded deformation structures. I. Regional strain, local perturbations, and deformation bands
Authors: Cobbold P. R.
Published: October 2017

Most natural deformations are variable in intensity throughout a given region. If the variations are evenly distributed and sufficiently numerous, it is useful to consider a measure of average strain for the region. In this paper, the average deformation and average strain for a region are defined in terms of the local deformation gradients at each point. The definition is compatible with calculations based on the boundary shapes of the region before and after deformation. Using the average deformation as a threshold value, local variations are expressed as deviations from the average, i.e. perturbations. It is demonstrated that the perturbations are independent of the regional strain and that their mathematical form is limited by certain constraints.If the perturbations have the form of straight-sided bands, it is shown that they must result from a differential simple shear, a differential simple shortening, or combinations of these. This distinction forms the basis of a classification proposed for banded perturbations: those formed by simple shear are S-bands; those by simple extension, P-bands; those by combined action, PS-bands. Many natural structures resulting from deformation in rocks (e.g. kinks, pressure-solution seams, shear zones, similar folds) are band-like in form and can be classified as above.
The Gow Lake impact structure, northern Saskatchewan
Authors: Thomas M. D. , Innes M. J. S.
Published: October 2017

Gow Lake, in the Precambrian Shield of Saskatchewan, is circular, 4 km in diameter, and has a large central island. Granites and quartzofeldspathic gneisses are exposed around the perimeter of the lake, whereas the island is formed largely of brecciated equivalents. Most of the breccias are composed entirely of clastic material, but at one locality fine-grained felted matrices form a significant component of the breccias, and coronas of clear glass surround quartz grains. The latter breccias also contain microscopic features characteristic of shock metamorphism, among which multiple sets of planar deformation structures in quartz are particularly diagnostic. Similar shock metamorphic features have been widely reported from terrestrial meteorite craters; accordingly, Gow Lake is interpreted as a deeply eroded impact crater and the felted matrices as impact melts.A local negative gravity anomaly with an amplitude of 3 mGal centered on the lake is attributed mainly to highly fractured basement rocks underlying the lake, which model studies indicate may extend to a depth of 900 m. A provisional minimum age of 100 Ma is proposed for the crater.
Brittle deformation of hornblende in a mylonite: a direct geometrical analogue of ductile deformation by translation gliding
Authors: Allison Iain , Tour Timothy E. La
Published: October 2017

Hornblende in a mylonitic rock from the Grenville front has deformed by fracture and slip on a parting subnormal to the c crystallographic axis. Rotation of the fragments during progressive deformation produced a preferred orientation of poles to the slip plane. When this slip plane had rotated close to the plane of the foliation, slip occurred on a second plane. This process is envisaged as being analogous to translation gliding in crystals.
Les volcaniclastites du complexe rhyolitique du Cap d'Ours, Rouyn-Noranda, Québec : exemples des mécanismes de fragmentation et de mise en place dans le volcanisme felsique
Authors: Tassé Normand , Gauthier Nicole , Lajoie Jean , Gélinas Léopold
Published: October 2017

The Cap d'Ours Complex in the Rouyn area, previously named the Glenwood Rhyolite, includes three types of rhyolitic volcanoclastites. Pyroclastites make up approximately half of the volcanoclastites; they are characterized by deposits with poor stratification and massive appearance, by aphanitic or pumiceous porphyric rhyolite blocks and lapilli, and by an association with variable proportions of pumice and shards. They seem to result from accumulated laminar flows similar to debris flows. The alloclastites form about one third of the volcanoclastites; they show several features common to the pyroclastites (stratified appearance, graded bedding, mixed source materials). However, some key parts of the outcrop indicate fragmentation in place, supporting the interpretation of a dome fragmented in situ and partially reworked. The autoclastites make up the remaining volcanoclastites. They are represented by flow breccia characterized by a progressive transition from a fragmented to a massive rhyolite. The Cap d'Ours Complex rhyolites form an arrangement of volcanoclastic components much more complex than described previously. In a single site occupying less than [Formula: see text], there are at least three types of volcanoclastites formed by different volcanic processes as varied as the eruption of pyroclastic and magmatic flows, and the injection and destruction of a dome or a spine. [Journal Translation]
Description and ecology of Recent endolithic biota from the Gulf Islands and banks in the Strait of Juan de Fuca, British Columbia
Authors: Henderson C. M. , Styan W. B.
Published: October 2017

Eleven endolithic forms were distinguished from skeletal fragments collected near the Gulf Islands and from banks in the Strait of Juan de Fuca, British Columbia. The vast majority of studies dealing with endoliths are from tropical regions; however, the abundance of boring organisms described herein demonstrates their importance as sedimentological agents in mid-latitudes as well.Although some, if not most, of the borings occurred after the substrate organism was dead, the order of infestation was indeterminant. Fungal borings are densely distributed when in close proximity to algae. Although the nature of this biological association remains undefined, this relationship suggests that fungi prefer utilizing algae as an energy source. The observed decreased infestation of algal endoliths in shallow environs (less than 30 m) compared with that in deeper water might be attributed to less exposure in a high energy regime or to a freshness factor of the shells. Algal endoliths were observed in several shell substrates obtained from below the photic zone (defined as 45 m on the basis of the deepest occurrence of encrusting red algae). This distribution of endolithic microphytes indicates that any bathymetric zonation that may have been initially present was disturbed by the lateral transport of substrate particles. Furthermore, this suggests that algal borings should not be used independently of other environmental information to determine paleobathymetry.
Glaciotectonic structures as useful ice-movement indicators in glacial deposits: four Canadian case studies
Authors: Hicock Stephen R. , Dreimanis Aleksis
Published: October 2017

Glaciotectonic deformation structures are useful directional indicators of ice movement but are rarely reported by North American authors. Being three-dimensional, they are commonly conspicuous in cleaned sections. Measuring just a few of them can provide accurate ice-movement directions at a site, and they assist in deciphering the interaction of past glaciers and their substrata. This paper concentrates on structures (generally less than 10 m long) in unconsolidated sediments that were induced by overriding glacial ice. Examples and interpretations of various types of structures are presented in four new Canadian case studies from British Columbia and southern Ontario that illustrate different deformational circumstances in sediments of various ages.
Sr isotopic study of Helikian sediment and diabase dikes in the Athabasca Basin, northern Saskatchewan
Authors: Armstrong Richard Lee , Ramaekers Paul
Published: October 2017

The Athabasca Group overlies 1.8 Ga or older basement of the Churchill Province and predates uranium mineralization at 1.3 Ga. Cross-cutting diabase dikes have been dated by Rb–Sr mineral isochrons at 1.31 ± 0.07 Ga at Diabase Peninsula, Cree Lake, and 1.16 ± 0.04 Ga at Lazy Edward Bay, Cree Lake. Initial 87Sr/86Sr ratios for these dikes are 0.7040 ± 0.0005 and 0.7036 ± 0.002, respectively. Clastic sedimentary rocks of the Athabasca Group normally show limited variation in Rb/Sr and variable initial 87Sr/86Sr. Sedimentary rocks in two areas near the northern margin of the Athabasca Basin scatter about isochrons of 2.6 Ga, reflecting Archean provenance of detrital material and lack of Sr isotopic homogenization since deposition. Sediment of the tuffaceous Wolverine Point Formation, near Rumpel Lake, is much more variable in Rb/Sr and enriched in Rb relative to Sr and defines a 1.43 ± 0.03 Ga isochron with a 0.7057 ± 0.0005 initial ratio. This is possibly the age of deposition of the Athabasca Group.
The subsidence of the Williston Basin
Authors: Fowler C. M. R. , Nisbet E. G.
Published: October 2017

A detailed comparison between the pre-Cretaceous stratigraphic record in the Williston Basin and the available information about Phanerozoic sea-level changes indicates that most stratigraphic breaks in the basin reflect eustatic control. The basin appears to have been subsiding continuously and steadily about the same centre for most of the Phanerozoic above a thick (55 km) continental crust. Deposition kept up with subsidence, and most of the sedimentary record was laid down close to sea level. Erosional breaks in the stratigraphic record may represent periods of removal of strata during episodes of low sea level. A possible explanation of this essentially steady, nonexponential subsidence record is that a mafic subcrustal body is undergoing transformation to eclogite.
Allochthonous Permian micro- and macrofauna, Kamloops area, British Columbia
Authors: Nelson Samuel J. , Nelson Eric R.
Published: October 2017

The first waagenophyllid coral to be described from the Western Hemisphere has been found in Permian rocks of the "Harper Ranch Group," near Kamloops, southern British Columbia. It is Parawentzelella?(Miyagiella) johnstonae sp. nov., associated with the tabulate coral Multithecopora?larushi sp. nov., numerous brachiopods, and other fossils. The containing rocks are considered to be allochthonous, originating in the western part of the Paleopacific Tethyan Ocean or in an island-arc complex farther to the north.The outcrop yielding the fossils appears to be a stratigraphic misfit, both in age and origin. Fusulinids from adjacent areas are of Early Permian (Wolfcampian) age but those associated with the fossils indicate a Late Permian (Guadalupian) age. These conflicting dates cannot, at present, be reconciled. The Tethyan origin of the fauna also contrasts with that of surrounding rocks, which are "non-Tethyan."
Scauménellisation de l'Acanthodii Triazeugacanthus affinis (Whiteaves) de la formation d'Escuminac (Dévonien supérieur de Miguasha, Québec) : révision du Scaumenella mesacanthi Graham-Smith
Authors: Béland Pierre , Arsenault Marius
Published: October 2017

Scaumenella mesacanthi (Graham-Smith, 1935) from the Escuminac Formation (Upper Devonian, Miguasha, Quebec) was originally described tentatively as a chordate, probably a vertebrate. It was later variously considered to be a larval ostracoderm or some early form of prochordate, the latter being the commonly accepted interpretation. We present a new description while associating it with the subclass Acanthodii, namely, Triazeugacanthus affinis (Whiteaves). We show that "Scaumenellas" are the remains of T. affinis that have undergone a degradation during fossilization, which we name scaumenellization.
Behaviour of dissolved iodine in the upper St. Lawrence Estuary
Authors: Takayanagi Kazufumi , Cossa Daniel
Published: October 2017

The concentrations of dissolved total iodine and iodate were determined in the water samples collected from various depths at 14 stations located in the upper St. Lawrence Estuary. The concentrations of total iodine and iodate ranged from undetectable (< 0.008 μM) to 0.40 μM and from undetectable to 0.36 μM, respectively, and salinities ranged from 0 to 33.9‰. The concentrations of total iodine and iodate increased with increasing salinity, and they correlated linearly with salinity. This implies that both total iodine and iodate behave conservatively in the estuary. The concentration of iodide, calculated as the difference in the concentrations of total iodine and iodate, was low throughout the estuary. Iodate was the major species of dissolved iodine in the upper St. Lawrence Estuary.
Transpression in slates along the margin of an Archean gneiss belt, northern Ontario—magnetic fabrics and petrofabrics
Authors: Borradaile G. , Sarvas P. , Dutka R. , Stewart R. , Stubley M.
Published: October 2017

Archean slates along the northern boundary of the Quetico subprovince of the Superior Province show marked variations of the structural facing direction within coplanar primary cleavage surfaces. These are interpreted as being due to sheath folds near the faulted east–west boundary of the slates with the metavolcanic Wabigoon Belt. Sheath folds with axial traces nearly parallel to the belt boundary are macroscopic, primary, and isoclinal and are believed to result from pervasive dextral transpression of the northern margin of the Quetico subprovince. Magnetic fabrics confirm the presence of a single penetrative flattening tectonic microfabric and considerable north–south shortening on the scale of hand specimens and outcrops. The magnetic fabric is due to the alignment of metamorphic sheet silicates, with a subordinate contribution due to the preferred dimensional orientation of detrital magnetite grains. In some low-strain environments at the hinges of sheath folds and at the sandy bases of graded beds relict sedimentary magnetic fabrics are preserved. However, a tectonic magnetic fabric is usual, with flat susceptibility ellipsoids parallel to axial planes and with variably oriented maximum susceptibility directions. To the south, farther into the interior of the Quetico subprovince, the primary folds become more homoaxial and the metamorphic grade rises rather steeply, and still farther south, small-scale polyphase deformation becomes evident especially where the rocks are remobilized.
Jura-Cretaceous (Oxfordian to Cenomanian) stratigraphy of the north-central Bowser Basin, northern British Columbia
Authors: Cookenboo H. O. , Bustin R. M.
Published: October 2017

Three new formations of Late Jurassic and Early to mid-Cretaceous age are defined for a 2000 m thick section of Jura-Cretaceous rocks exposed in the north-central Bowser Basin. The Currier Formation (Oxfordian to Kimmeridgian or Tithonian) consists of 350–600 m of interbedded shales, siltstones, sandstones, coals, and carbonates. The McEvoy Formation (Barremian to as young as Albian) consists of 400–800 m of siltstones and shales with minor sandstones, thin coals, limestones, and conglomerates. The Devils Claw Formation (in part mid-Albian to Cenomanian) consists of 300–600 m of strata characterized by thick pebble and cobble conglomerates, with associated coarse sandstones and minor siltstones and shales.Two successive coarsening-upward sequences are identified in the study area. The first begins with Middle Jurassic marine shales of the Jackson unit grading upwards to coarser Upper Jurassic facies of the Currier Formation. The Currier Formation is conformably or unconformably overlain by siltstones and shales of the Lower Cretaceous McEvoy Formation, which forms the base of a second coarsening-upward sequence. Conglomerates appear with increasing frequency in the upper McEvoy and are the dominant lithology of the overlying Devils Claw Formation. The contact between the McEvoy and Devils Claw formations is gradational. The Devils Claw Formation forms the top of the second coarsening-upward sequence.The Currier Formation (Late Jurassic) is equivalent to the upper units of the Bowser Lake Group. The McEvoy and the Devils Claw formations (Barremian to Cenomanian) are coeval with the Skeena Group (Hauterivian? to Cenomanian). A probable unconformity separating the Upper Jurassic Currier Formation from the Lower Cretaceous McEvoy Formation correlates with a hiatus in the southern Bowser Basin and probably represents a regional unconformity.
Microspherules in Devonian sediments: origins, geological significance, and contamination problems
Authors: Wang K. , Chatterton B. D. E.
Published: October 2017

We have studied various microspherules (<0.5 mm across) that were found in Devonian sediments from Canada and China during our micropaleontological studies (e.g., conodont picking). These spherules are similar in appearance, but they are quite different in origin. A combined scanning electron microscope, energy dispersive X-ray, X-ray microdiffraction, and electron microprobe analysis enables us to determine their probable origins: phosphatic conodont pearls of biological origin; silicate glass microtektites of terrestrial meteorite-impact origin; and black, magnetic iron spherules of probable extraterrestrial origin. We also observed some contaminant spherules (glue spatters and steel slag) of artificial origins. Studies of natural spherules in sediments can provide important geological information that may be otherwise undetectable.
Stratigraphy and U – Pb zircon geochronology of Kidd Creek: implications for the formation of giant volcanogenic massive sulphide deposits and the tectonic history of the Abitibi greenstone belt
Authors: Bleeker Wouter , Parrish Randall R.
Published: October 2017

Within the context of a structural–stratigraphic analysis of the giant Kidd Creek Cu–Zn–Ag deposit, precise U–Pb zircon ages have been obtained for five critical rock units associated with the deposit. Massive, flow-banded footwall rhyolite is dated at 2714.3 ± 1.2 Ma, slightly younger than a previously published age of 2717 ± 2 Ma on nearby rhyolite breccia. Extrusive rhyolite in the immediate hanging wall to the main ore lenses is dated at 2711.5 ± 1.2 Ma, leaving an interval of one to several million years for the formation of the deposit. We consider the demonstrated longevity of the Kidd Creek hydrothermal system as a major control on its giant size. Age constraints together with the size of the deposit suggest a time-averaged rate of base-metal sulphide deposition of about 10–100 t/year. Peak rates were likely one to possibly two orders of magnitude above time-averaged rates, hence 100–1000 t/year or higher. Detrital zircon ages on greywackes in the structural footwall to the deposit support structural observations that the metasediments are unrelated and significantly younger than the volcanics that host the deposit. All greywackes near Kidd Creek are younger than 2699 Ma and should be included in the Porcupine Group, which is redefined to include "Keewatin-age" greywacke turbidites that overlie the Krist Fragmental unit, but are themselves overlain by polymict conglomerates at the base of the Timiskaming sequence. The Prosser Porphyry, a quartz–plagioclase-porphyritic granitoid stock northeast of Kidd Creek, is dated at [Formula: see text] Ma, supporting structural observations that it is not a synvolcanic intrusion.
Pétrographie et altération de la matière organiquedu gisement de plomb–zinc–cuivre de tourist–Bou Beker,Maroc nord oriental
Authors: Bouadellah M. , Brown A. C. , Héroux Y.
Published: October 2017

Reflectance measurements and organic petrography were used to study altered organic matter in the dolomitic Middle Jurassic Beddiane sequence hosting the Beddiane lead–zinc deposit. Organic matter occurs in the lower dolostone units of the formation where zinc sulfide mineralization prevails. The upper units, where lead sulfide mineralization is dominant, contain lesser amounts of organic matter. The organic matter in the Beddiane sequence consists of macerals, amorphous kerogen, and solid bitumen, inertinite and vitrinite are ubiquitous. The amount of exinite increases toward mineralized areas but the ratio exinite/kerogen remains constant. Two types of vitrinite are considered on the basis of their reflectance: Vt1 with low reflectance values (0.3–0.5%) and Vt2 with higher values (0.7–1.25%). The ratio Vt1/Vt2 increases and the reflectance values for Vt1 decrease toward the zinc-prevailing units, Organic matter associated with the mineralization exhibits features such as oxidation halos and desiccation cracks, together with a low-fluorescent exinite. The association of the kerogen content, the trend in reflectance values, and the alteration features of the Mississippi Valley-type Beddiane deposit support the hypothesis that the regional flow of hot brines associated with the mineralization process was the cause of anomalous heating, that the occurrence of exinite maceral and its associated gas played a role in the ore deposition, and that the new chemical equilibrium reached by the zinc-dominant host rock after ore deposition is responsible for the suppressed reflectance values within and near the ore deposits.
A Late Cretaceous (Turonian) Ichthyofauna from Lac des Bois,Northwest Territories, Canada, with paleobiogeographic comparisons with Turonian ichthyofaunas of the Western Interior Seaway
Authors: Fielitz Christopher
Published: October 2017

A fish fauna from a Turonian sequence of the Great Bear Basin at Lac des Bois is described. The fauna includes examples of Ichthyodectes, cf. Osmeroides, a euteleost, and several aulopiforrn fishes such as Enchodus, Cimolichthys, and a juvenile that cannot be further identified. The fauna of Lac des Bois most closely resembles other Arctic fish assemblages of the Western Interior Seaway based on a UPGMA (unweighted pair-group method with arithmetic averages) cluster analysis of various North American Turonian localities. There are also slight differences between eastern and western localities along the seaway. The north–south differences of the ichthyofauna can be explained by current patterns distributing the fishes in the seaway, or transgressive events during the Turonian. The east–west differences may be due to changes in water depth from east to west.
Wenlock, Ludlow, and Pridoli? graptolites from Yulin, Guangxi, China
Authors: Lenz Alfred C. , Chen Xu , Ni Yu-Nan
Published: October 2017

Late Wenlock and Ludlow transition graptolites are better developed and more diverse in the Yulin region of Guangxi Province, South China, than elsewhere in China. The upper Homerian (upper Wenlock) graptolites, while moderately diverse, are not amenable to a zonal subdivision because key species such as Colonograptus praedeubeli, Colonograptus deubeli, and Colonograptus ludensis are found to completely overlap in their occurrences. Ludlow graptolites, all probably assignable to the lowest Ludlow nilssoni–colonus Biozone, include Lobograptus progenitor, Colonograptus colonus, Colonograptus gerhardi, and Bohemograptus bohemicus (sensu lato). The single occurrence of Monograptus cf. rectiformis Príbyl is the only species suggestive of Pridoli-age strata. The overall faunal assemblages are composed predominately of cosmopolitan species, but two species, Colonograptus gerhardi and Monograptus cf. rectiformis, provide minor support for the suggestion that the Yunkai Block in which the Yulin region is situated was originally part of Gondwanaland.
Foraminifera and Arcellacea from Porters Lake, Nova Scotia: modern distribution and paleodistribution
Authors: Laidler R. B. , Scott D. B.
Published: October 2017

Assemblages of foraminifera and Arcellacea examined from surficial sediment samples collected in Porters Lake, Nova Scotia, reflect the strong gradient from freshwater to marine water in the four basins of this lake. The only marine connection is a channel 3 m below higher high water. The transition from fully freshwater to marine is abrupt, with no "intermediate" arcellacean fauna, as we have observed in cores from other areas of the Maritimes, Given the present connection is 3 m below higher high water, it has been almost 1500 years since this sill first became tidal (based on 20 cm/100 year sea-level rise from nearby Chezzetcook Met over the last 3000 years); however, the upper fjord-like part of Porters Lake, although connected to the ocean, is still completely freshwater, suggesting at least a 1500 year time lag for marine conditions to penetrate upper reaches of the lake. For the first time, we are provided with a time frame of how long it takes for marine conditions to extend into remote parts of an estuary, which could have implications for interpreting records from other similar fjord-type estuaries, such as Bedford Basin, Nova Scotia. Evolution of the lake through time was studied from three cores: one from the present most marine conditions, one from an intermediate area, and one from the uppermost freshwater part of the lake. Porters Lake has experienced marine transgression for at least the last 3000 years, with one closure between 1500 and 2000 BP. Bottoniset beds from a glaciogenic gravel delta at the head of the lake were dated at 11 750 BP; this is similar to an age on a delta offshore that is now in 70 m of water.
Minturn circles: a new glacial feature
Authors: Appel Peter W. Uitterdijk
Published: October 2017

In Inglefield Land, northwest Greenland, a new glacial feature has been found, consisting of well-defined circles and rings ranging in size from a few metres to about 80 m in diameter and in colour from black to pink. More than 300 circles and rings are known. They are composed of slightly rounded boulders, cobbles, and pebbles frequently overgrown with black lichen. The circles and rings consist of syenite that was picked up by the inland ice under permafrost conditions by a melting–refreezing process. The syenite till was subsequently transported by the inland ice across Ingiefield Land and deposited in cut-off meanders of melt-water streams on the surface of the stagnant ice cap. During melting of the inland ice the circles and rings were deposited on a peneplain consisting of boulder fields and outcrops of Precambrian and Cambrian rocks. These circles are probably quite common features in high-arctic regions, but their recognition requires special conditions.
Permian alkaline basalts associated with formation of the Sverdrup Basin, Canadian Arctic
Authors: Cameron B. I. , Muecke G. K.
Published: October 2017

Permian basaltic rocks of the Esayoo Formation attended lithospheric extension that formed the Sverdrup Basin in the Canadian Arctic. North of Greely Fiord, northern Ellesmere Island, subaerial flows of the Esayoo Formation attain a maximum thickness of 300 m, but thin rapidly westward, where pillow lavas, epiclastic basalt conglomerate, and associated marine sedimentary rocks indicate proximity to an ancient shoreline. Element-mobility studies demonstrate that modifications of many major elements and some of the large ion lithophile elements accompanied low-grade burial metamorphism. Discriminant diagrams involving only the relatively immobile trace elements reveal within-plate alkaline to transitional basalt affinities. Trace element data (mean Th/Ta = 1.7) do not register significant lower crustal contamination. Models utilizing rare earth clement ratios and Ni–Cr relations suggest that variable degrees of partial melting of an enriched garnet lherzolite and minor combined olivine–clinopyroxene fractional crystallization can account for the described compositional diversity. Nb–Ta peaks (mean La/Nb = 0.99) in spider diagrams identical to ocean-island basalts characterize magmas derived from the asthenospheric mantle with minimal subcontinental lithospheric contribution and continental contamination. Small rates of continental extension during the Carboniferous generated small-volume alkaline melts that passed unadulterated through the subcontinental lithosphere and crust during ascent from their asthenospheric mantle source.
Late-glacial flow patterns, deglaciation, and postglacial emergence of south-central Baffin Island and the north-central coast of Hudson Strait, eastern Canadian Arctic
Authors: Manley William F.
Published: October 2017

New georaorphic, sedimentologic, and chronologic data are used to reconstruct late Quaternary ice-sheet flow patterns, deglaciation, and isostatic uplift along the largest marine trough connecting the Laurentide Ice Sheet with the North Atlantic Ocean. The Lake Harbour region was targeted for study given its potential to record flow from several ice-dispersal centers. Striations and sediment provenance indicators define flow patterns. Thirty-four radiocarbon dates constrain a chronology of events. Centuries or millennia(?) before deglaciation, a southeast-flowing ice stream impinged on southernmost Big Island, as recorded by a single striation site and delimited in extent by geomorphic evidence of cold-based ice. During the Cockburn Substagc (9000–8000 BP), the region was scoured by southward to southwestward flow from an ice cap on Meta Incognita Peninsula, as recorded by 60 striation sites along 200 km of coastline. Carbonate erratics are uncommon in till above the marine limit. Where present, they suggest that southward flow reworked older drift. At about 8200 BP, the area was dcglaciated, and the marine limit was established at elevations of 67–141 m above high tide. Iceberg calving and sediment discharge from an ice margin in Ungava Bay, Hudson Bay, or Foxe Basin then blanketed the area with limestone-rich glaciomarinc sediment. Afterward, the region experienced slow but sustained emergence. The data revise the maximum lateral extent of a Late Wisconsinan ice stream in Hudson Strait and emphasize the extent of a late-glacial ice cap on western Meta Incognita Peninsula.