bluuebunny/crossref_metadata_2025 huggingface dataset:
Évolution d'un milieu littoral et remontée du niveau relatif de la mer à l'Holocène supérieur au nord de l'île du Cap-Breton, Nouvelle-Ecosse
Authors: Vernal A. de , Lortie G. , Larouche A. , Scott D. B. , Richard P. J. H.
Published: October 2017

The sedimentary sequence in a coastal pond on Cape Breton Island was examined by various analyses (pollen, plant macrofossils, diatoms, and rhizopods). The results allow for the reconstruction of different phases in the evolution of the pond in conjunction with relative sea-level rise during the late Holocene. Throughout the period studied the microflora and microfauna indicate that the pond was mainly freshwater, isolated from the sea by a continuous sand and gravel bar. Three phases in the pond evolution have been identified: (1) the lowermost part of the sequence is characterized by mineral detrital deposits and some marine fossils related to the reworking of bar sediment by storms and high tides washing over the rock sill; (2) this was followed by a rapid filling of the basin by organic detritus provided by shore washing processes; (3) a marsh evolving into a shallow lake completes the sequence up to the interruption by human occupation. The lake-level rise is linked to the formation of the bar, which was controlled by the highest storm-beach level. A submersion rate of 18 cm/century has been calculated using the beginning of the lacustrine phase, which was dated at 2680 years BP (UQ-616).
The last glaciation of west-central Ellesmere Island, Arctic Archipelago, Canada
Authors: Hodgson D. A.
Published: October 2017

Locally abundant ice-marginal landforms lie in a 500 km long zone with a distal margin 10–60 km west of the margins of modern ice caps on central Ellesmere Island. Much of this drift belt, at the heads of the fiords, was deposited by the oscillating margin of a coalesced predecessor of the modern ice caps between 9000 and 7000 BP. The ice continued to retreat east of the present margin, and readvanced to its modern limit in a middle and late Holocene cooler climate. Unweathered but undated till and striations at the base of the drift suggest that the belt does not mark the western limit of central Ellesmere Island ice in the last glaciation. The limit lies an unknown distance downfiord; glaciers in the fiords may have floated. No reliable evidence was found for a complete ice cover of western Ellesmere Island and Eureka Sound in the last glaciation; nevertheless much of central and southern Ellesmere Island and Devon Island may have been glaciated by a regime that left few erosional or depositional landforms. Alternatively, emergence of an unglaciated Eureka Sound, underway by 9000 BP, may have followed combined peripheral glacioisostatic depression by encircling ice caps, whereas at the drift belt emergence was less and later, controlled only by central Ellesmere Island ice.
Geothermal energy potential in the Hinton–Edson area of west-central Alberta
Authors: Lam H.-L. , Jones F. W.
Published: October 2017

The Hinton–Edson area, located about 200 km west of Edmonton in Alberta, coincides with a geothermal anomaly of relatively high average geothermal gradient (~36 °C/km). The anomaly was discovered by Lam et al. during a study of a large number of bottom-hole temperatures. The high gradient and the thick sedimentary section in the area (4–6 km) provide a possible low-grade geothermal energy source for the growing population centres and industry. A survey of petroleum exploration data in the area has been made to determine if aquifers exist from which hot water may be recovered with reasonable flow rates and salinities for low-grade geothermal use. The results show that aquifers with prospective geothermal potential exist in the porous carbonate rocks of the Mississippian and Upper Devonian. Also, water movement is inferred from formation-water analyses, and this supports the suggestion that the geothermal anomaly is caused by the movement along fault planes of water that has been heated at depth.
Pre-Vashon fossil Coleoptera of Fraser age from the Fraser Lowland, British Columbia
Authors: Miller R. F. , Morgan A. V. , Hicock S. R.
Published: October 2017

Samples of organic silt from post-Coquitlam Quadra sand at Port Moody and Mary Hill, British Columbia (dated at 18 300 and 18 700 years BP, respectively) were examined for insect remains and yielded small assemblages of beetles.At Port Moody species of the family Staphylinidae, whose members are often associated with moss or leaf litter, are the most abundant fossils present. Other specimens included open-ground beetles of the family Carabidae, as well as weevils (Curculionidae) and bark beetles (Scolytidae), which inhabit conifers. The assemblage appears to represent an open forest-floor community. Some of the species in this site have distribution ranges that do not include the Port Moody area today, but do occur in the interior of British Columbia and at higher altitude near the coast. One of the most numerous species, Micropeplus laticollis Mäklin, occurs in duff of conifers including Picea engelmannii, Abies lasiocarpa, Pinus ponderosa, and Pinus contorta. These trees are characteristic of the subalpine forest. The insect assemblage suggests an in situ deposit, subalpine in nature, probably in a cool but dry environment that developed during the short episode when this part of the Fraser Lowland was ice free between the Coquitlam and Vashon ice advances.The beetle assemblage from Mary Hill Quadra sediments probably indicates that a bog environment existed at that time; however, the lack of specific identifications precludes detailed paleoclimatic interpretation.
Paleomagnetism of the komatiitic basalts of the Ottawa Islands, N.W.T.
Authors: Buchan K. L. , Baragar W. R. A.
Published: October 2017

The komatiitic basalts of the Ottawa Islands in eastern Hudson Bay are on strike with and believed to form a continuation of similar units of the Cape Smith Belt 150 km to the northeast. Units sampled in the Ottawa Islands all dip gently to the west and hence are not suitable for an internal fold test of their age of magnetization. However, before correcting for the tilt of the lavas, the dominant magnetization direction (D = 207.6°, I = 61.9°, k = 168, α95 = 3.7°) does not differ significantly from the uncorrected magnetization direction reported from the steeply dipping, northwest-facing units at Cape Smith (D = 218°, I = 60°, k = 47, α95 = 4°). This negative fold test suggests that the remanence at both locations was acquired after folding. Comparison with the North American Precambrian apparent polar wander path implies that overprinting is related to the Hudsonian Orogeny.A second stable magnetization directed to the west with a shallow inclination is superimposed on the dominant component at a number of sampling sites. Its direction is poorly defined and no fold test is possible. However, magnetic evidence suggests that this component was probably acquired as an overprint after the dominant magnetization, perhaps during a mild reheating associated with the Elsonian Orogeny.
Late Cretaceous to early Tertiary magnetostratigraphy of a continental sequence: Red Deer Valley, Alberta, Canada
Authors: Lerbekmo John F. , Coulter Kenneth C.
Published: October 2017

The Red Deer Valley exposes a conformable 350 m thick late Campanian to Early Paleocene fluvial–deltaic coal-bearing sequence named the Edmonton Group. Systematic sampling and paleomagnetic analysis of the dominant lithologies (mudstones, sandstones, and shales) were carried out over five sections correlated by coal seams to provide some 500 sites (stratigraphic levels). Primary detrital remanent magnetization directions after alternating field cleaning produce a polarity reversal pattern correlatable to sea-floor magnetic anomalies 29–33.The Campanian–Maastrichtian boundary, based upon the first appearance of Wodehouseia, and the Maastrichtian–Paleocene (Cretaceous–Tertiary) boundary, based upon an Ir anomaly associated with dinosaur and Cretaceous palynofloral extinctions, correlate closely magnetostratigraphically with the marine foraminiferal section at Gubbio, Italy. Radiometric dating of bentonites has indicated the ages of these boundaries to be approximately 71 and 64 Ma, respectively.
Paleomagnetic evidence for displacement from the south of the Coast Plutonic Complex, British Columbia
Authors: Irving E. , Woodsworth G. J. , Wynne P. J. , Morrison A.
Published: October 2017

The mid-Cretaceous Spuzzum and Porteau plutons of the Coast Plutonic Complex of British Columbia have two magnetizations, A and B. The A magnetization (eight sites, 83 specimens, D = 30.3°, I = 56.7°, α95 = 4.9°, paleolatitude = 37 ± 5°N, paleopole 65.0°N, 14.9°W, A95 = 6.2°) is considered to have been acquired in the age range 105–90 Ma. This result differs from the field established for cratonic North America in this time range. The difference could be caused either by previously undetected tilting about a horizontal axis of the plutons, or by their rotation about a vertical axis and lateral displacement relative to the craton. Previously observed mid-Cretaceous magnetizations from other rock units from the western Canadian Cordillera and the Cascades of Washington, United States, are similarly discordant with respect to the craton. This similarity over such a large area indicates that, although local undetected tilting could be partly responsible, it is unlikely to be the prime cause, and we argue therefore that lateral displacement and rotation have occurred. It would seem that much of the western part of the Canadian Cordillera has moved north by about 2400 km and rotated clockwise since the mid-Cretaceous. The paleolatitude of the southern Coast Plutonic Complex of British Columbia is statistically identical to that recently observed (39 ± 3°N) for three plutons from the Central Sierra Nevada of California, which raises the possibility that the two complexes were much closer together at the time of their emplacement than at present. The second magnetization called B (four sites, 27 specimens, D = 5.1°, I = 67.6°, α95 = 4.7°, paleopole 86.5°N, 51.2°W) is parallel to the mid-Tertiary field, as previously determined from nearby intrusions, and is considered to be an overprint acquired during regional heating and low-grade metasomatism. Some earlier paleomagnetic studies of mid-Cretaceous rocks from the Coast Plutonic Complex indicated either an absence of displacement or uncertain evidence for it, and we attribute this to the nonrecognition, in this earlier work, of similar magnetically stable overprints of Tertiary age. Overprints in several Triassic rock units in the western Cordillera are parallel to the A magnetization, indicating that the mid-Cretaceous and the mid-Tertiary probably were periods of severe magnetic overprinting in British Columbia. Mid-Cretaceous and Late Triassic results from the western Cordillera of British Columbia are systematically different, indicating that movements relative to the craton occurred between these times.
Cambrian volcanism in Nova Scotia, Canada
Authors: Murphy J. B. , Cameron K. , Dostal J. , Keppie J. Duncan , Hynes A. J.
Published: October 2017

Cambrian volcanic rocks in Nova Scotia occur in small grabens or half grabens in the Avalon Zone (Composite Terrane) as part of a thin sequence of continental to shallow-marine Cambro-Ordovician rocks. In the northern Antigonish Highlands, the volcanic rocks occur mainly in the Lower Cambrian McDonalds Brook Group. In southern Cape Breton Island, they occur predominantly in the Middle Cambrian Bourinot Group. The chemistry of these volcanic rocks indicates that they are bimodal (basalts–rhyolites) and within plate. The basalts are alkalic in the Antigonish Highlands and tholeiitic in Cape Breton Island. The rising basaltic magma is postulated to have produced the felsic magma by anatexis of the crust. It is proposed that the Antigonish Highlands volcanic rocks erupted in a small pull-apart basin. A similar structural setting is probable in southern Cape Breton Island, but there the bounding faults are poorly exposed. These basins probably formed during a period of transpression in the last stages of the late Hadrynian Cadomian deformation.
Analysis of the trace-element content of coals from the Carboniferous Cumberland Group, near Joggins, Nova Scotia, Canada
Authors: Kaplan Sanford S. , Donahue Jack , Carr James D. , Kelter Paul B.
Published: October 2017

Trace-element concentrations including Mg, Cr, Mn, Ni, Cu, Zn, Cd, and Pb are reported for six coal beds located in the Cumberland Group (Westphalian B or Lower Pennsylvanian) at the Joggins section, Nova Scotia, Canada. The coal beds were deposited on small flood plains. The higher than usual heavy-metal trace-element concentrations in the coals may have been derived in the exposed Cobequid Massif, located south of the Joggins area.
Crandallite group minerals in the Helikian Athabasca Group in Alberta, Canada
Authors: Wilson John A.
Published: October 2017

Members of the crandallite group of aluminous hydroxy phosphates are present in trace amounts in every formation of the Athabasca Group in Alberta. The minerals of the group present in Alberta form a solid-solution series with end members goyazite (SrAl3(PO4)OH5), crandallite (CaAl3(PO4)OH5), and gorceixite (BaAl3(PO4)OH5). These minerals are present as cubes and subhedral grains, 2–20 μm across, in isolation or in clusters interstitially in the Athabasca Group sandstones, siltstones, and tuffs. Petrographic study indicates an authigenic origin for the crandallite-group minerals in the Athabasca Group. Their presence, locally, beneath quartz overgrowths and early diagenetic fluorapatite suggests formation very early in the post-depositional history of the rock. The presence of the crandallites within the regolith beneath the Athabasca Group and within a metamorphic rock fragment incorporated into the sandstone suggests more than one origin for the minerals and possibly a detrital component.
Compositional variability of Mazama tephra magnetites
Authors: Osborn Gerald
Published: October 2017

Magnetites of anomalous composition found in association with known Holocene tephras in Banff and Jasper national parks were originally thought to represent a new tephra of unknown origin, but were later associated with Mazama tephra at two other sites in Alberta. New data from Alberta, British Columbia, and Montana confirm the compositional variability of Mazama tephra. The range of magnetite compositions presumably was produced by an inhomogeneous magma chamber, for which there is evidence in the case of the Mazama eruption.
Osteology and relationships of Chirostenotes pergracilis (Saurischia, Theropoda) from the Judith River (Oldman) Formation of Alberta, Canada
Authors: Currie Philip J. , Russell Dale A.
Published: October 2017

A partial skeleton of a small theropod found in the Judith River Formation of Dinosaur Provincial Park (Alberta) shows that Chirostenotes pergracilis is the same animal as "Macrophalangia canadensis" and probably "Ornithomimus elegans." New information on the skeleton suggests that Chirostenotes is closely related to Elmisaurus and Oviraptor and that these animals are derived from dromaeosaurid stock. Both robust and gracile forms are known from Alberta, and it is suggested that these correspond to the two "species" of Caenagnathus and represent sexual dimorphism. Microvenator from the Lower Cretaceous of Montana may represent an early caenagnathid. Specializations in the pelvic girdle and hind limb may indicate wading habits.
Transpression in an Archean greenstone belt, northern Minnesota
Authors: Hudleston P. J. , Schultz-Ela D. , Southwick D. L.
Published: October 2017

Weakly metamorphosed Archean sedimentary and volcanic rocks of the Vermilion district, northern Minnesota, occupy an east–west-trending belt between gneisses of the Vermilion granitic complex to the north and the Giants Range batholith to the south. All the measured strain, a foliation, and a mineral lineation in this belt are attributed to the "main" phase of deformation (D2). Foliation strikes parallel to the belt and dips steeply, and the mineral lineation plunges moderately to steeply east or west and is parallel to the maximum stretching direction, X, and subparallel to fold hinges. An earlier, possibly nappe-forming, event (D1) left little evidence of fabric in the Vermilion district.A number of features indicate that the D2 deformation involved a significant component of dextral strike-slip shear in addition to north–south compression. They include ductile shear zones with sigmoidal foliation patterns, shear bands, asymmetric pressure shadows, and the fact that the asymmetry of the F2 folds is predominantly Z. Other features are more simply explained by a deformation involving simple shear. The S2 cleavage is locally folded, and a new spaced cleavage developed in an orientation similar to that of the old cleavage away from the folds. We consider this the result of a process of continuous shear, with perturbations of flow resulting in folding of S2 and the development of a new foliation axial planar to the folds. The same type of perturbation can lead to the juxtaposition of zones of constrictional and flattening strains, a distinctive feature of the rocks of the Vermilion district otherwise hard to account for. The strain pattern requires a north–south component of shortening in addition to shear. The D2 deformation in the Vermilion district can therefore be characterized as one of transpression: oblique compression between two more rigid lithospheric blocks to the north and south.
A radiometric age for the Cretaceous–Tertiary boundary based upon K–Ar, Rb–Sr, and U–Pb ages of bentonites from Alberta, Saskatchewan, and Montana
Authors: Baadsgaard H. , Lerbekmo J. F. , McDougall I.
Published: October 2017

Bentonites associated with coal seams at the North American Cretaceous–Tertiary (K–T) boundary in the Red Deer Valley of Alberta, in the Frenchman Valley of Saskatchewan, and near Hell Creek, Montana, were dated by the K–Ar, Rb–Sr, and U–Pb methods. Based upon palynological stratigraphic correlation and the presence of a sharp iridium anomaly, the three sampled bentonite horizons all occur less than 1 m above the established K–T boundary. There is evidence of possible systematic errors giving dating results outside nominal statistical error values. Despite possible constant errors, the weighted mean of nine average dates is calculated as 64.3 ± 1.2 Ma (2σ standard deviation). An unweighted averaging produces a grand mean age of 64.4 ± 1.2 Ma.
A faster method for erosion and dilation of reservoir pore-complex images
Authors: Parker J. R.
Published: October 2017

Studies of thin sections of reservoir rock have been conducted for some time with the goal of understanding flow behavior and estimating physical properties. These sections are essentially two dimensional, but it has always been assumed that the results obtained can be extrapolated to the third dimension. Computer image-processing techniques are often used in this sort of analysis because of the large amounts of data contained in a single digitized section image. One of the methods used to process these images is erosion–dilation, wherein layers of each pore are stripped off (erosion) and then replaced (dilation). This results in a smoothing of the pore perimeters and can be used to estimate pore radii, volume, and roughness. Because of the size of each image, erosion–dilation of images of the pore complex of reservoir rocks is a time-consuming process. A new method called global erosion is much faster, with no increase in memory requirement or decrease in accuracy. This should permit the processing of larger images or a greater number of small images than does the standard method.
Lead- and strontium-isotope geochemistry of Paleozoic Sicker Group and Jurassic Bonanza Group volcanic rocks and Island Intrusions, Vancouver Island, British Columbia
Authors: Andrew Anne , Godwin Colin I.
Published: October 2017

Whole-rock and galena lead-isotope analyses have been obtained from the Sicker Group Paleozoic island-arc volcanic package and from a Jurassic island-arc represented by the Bonanza Group volcanics and Island Intrusions. Galena lead-isotope analyses from the volcanogenic ore deposits at the Buttle Lake mining camp in the Sicker Group provide estimates of the initial lead ratios for the Sicker Group. Lead-isotope signatures are uniform within each of the major orebodies, but the Myra orebody is less radiogenic than the older H–W orebody. This has major significance in terms of ore genesis for these important deposits.There are significant differences in isotopic composition between the Sicker Group and Devonian island-arc type rocks in the Shasta district, California, which rules out direct correlations between the rock units of these two areas. Relatively high initial values of 207Pb/204Pb (> 15.56) and 208Pb/204Pb (> 38.00) suggest that large quantities of crustal lead must have been involved in the formation of the Sicker Group volcanic rocks. Thus it is proposed that the trench related to the Paleozoic island arc had a substantial input of continental detritus and may have lain near a continent.The Jurassic island arc is characterized by low 207Pb/204Pb ratios (< 15.59), suggesting a more primitive arc environment than for the Paleozoic arc. Bonanza Group volcanic rocks contain lead that is less radiogenic than lead in the Island Intrusions. Present and initial lead-isotope ratios of both the Bonanza Group volcanics and Island intrusions follow the same trend, supporting the hypothesis that they are comagmatic. Lead isotopes from a galena vein within the Island Copper porphyry deposit plot with the initial ratios for Bonanza Group volcanics and Island Intrusions. This confirms the hypothesis that this mineralization is related to the Jurassic island-arc volcanic event.Initial lead-isotope ratios for the Jurassic rock suite form a linear array on both 207Pb/204Pb versus 206Pb/204Pb and 208Pb/204Pb versus 206Pb/204Pb plots. If interpreted as due to isotopic mixing, the more radiogenic end member has a composition that is lower in 207Pb/204Pb and higher in 206Pb/204Pb than typical upper continental crust. Assimilation of Sicker Group material during the emplacement of the Jurassic arc can explain the mixing trend.
Lead- and strontium-isotope geochemistry of the Karmutsen Formation, Vancouver Island, British Columbia
Authors: Andrew Anne , Godwin Colin I.
Published: October 2017

Lead-isotope whole-rock ratios of the Triassic flood basalts of the Karmutsen Formation are heterogeneous, with 206Pb/2MPb = 18.72–21.51, 207Pb/204Pb = 15.56–15.77, and 208Pb/204Pb = 38.16–40.15. Whole-rock lead initial ratios are coincident with galena analyses having 206Pb/204Pb = 18.1–19.0, 207Pb/204Pb = 15.53–15.60, and 208Pb/204Pb = 38.2–38.6. Lead, uranium, and thorium concentrations are greater than for mid-ocean-ridge basalts, less than for island arcs, but similar to those in ocean-island and continental flood basalts. Isotopic similarities exist between the Columbia River – Chilcotin continental flood basalts and the Karmutsen Formation, suggesting similar origins for these basalts. The heterogeneity in whole-rock ratios can be explained in terms of isotopic mixing between a lead-rich average crustal lead type and an ocean-island basalt-type mantle source. Thus the Karmutsen Formation displays evidence for sediment contamination of the mantle.
Pattern of apparent total strain in the bedded anhydrite cap of a folded salt wall
Authors: Schwerdtner W. M. , Torrance J. G. , Berkel J. T. van
Published: October 2017

The dense anhydrite cap of the southern Muskox Ridge salt wall participated in the large-scale buckling of Mesozoic clastic strata at the western boundary of the Tertiary Eureka Sound fold belt on Axel Heiberg Island, Canadian Arctic. This Carboniferous anhydrite is an aggregate of strained diagenetic nodules and contains relict limestone beds that mark the paleohorizontal plane. The well-exposed cap provides an excellent example of fold decollement and redeformation of foliated rocks.The horizontal pattern of the nodule-shape fabric was delineated within folded and straight segments of the cap. Maps for a well-exposed folded segment show systematic variations in the intensity of apparent total strain (r) and the prolateness factor (k). If the nodule fabric pattern of adjacent straight walls represents the prefold structural state of all walls in the area, then the pattern of folding strain can be reconstructed in the southern Muskox Ridge cap. Here, the preflattened anhydrite was deformed by flexural shear in most localities, but was shortened passively near its contact with competent clastic rock.
Evolution of an Archean subprovince boundary: a sedimentological and structural study of part of the Wabigoon–Quetico boundary in northern Ontario
Authors: Devaney Jonathan R. , Williams Howard R.
Published: October 2017

A prograded clastic wedge, represented by formation- to group-scale units of metasedimentary strata in the Beardmore–Geraldton Terrane, developed in a transitional zone at the southern margin of a volcanic arc between the Onaman–Tashota Terrane, part of the Wabigoon Subprovince to the north, and the Quetico Subprovince, an accretionary prism to the south. Megasequences or couplets with lower basaltic and upper clastic sedimentary parts are now exposed as regionally metamorphosed mafic volcanic and sedimentary belts, outlining thrust slices. Relatively proximal facies (belts) are juxtaposed on top of more distal ones, forming a regional stratigraphy of repetitive volcanic–sedimentary megasequences produced in an imbricate thrust stack. A variety of minor and regional structural features illustrate accretion and subsequent transpression. Isoclinal folding associated with dip-slip, overthrust shearing was followed by inhomogeneous ductile strain of dextral sense along weak lithologies and existing shear zones. Possible subduction-related accretion added a monotonous sequence of arc-derived wacke turbidites to the underside of the thrust-imbricated arc-margin succession. Post-tectonic melting in the northern section of this tectonically thickened accreted sediment gave rise to S-type granites.
Deep burrowing in the early Palaeozoic deep sea: examples from the Cambrian(?)–Early Ordovician Meguma Group of Nova Scotia
Authors: Pickerill1 Ron K. , Williams Paul F.
Published: October 2017

Enigmatic and heterogeneously deformed burrows are described from the Cambrian?–Early Ordovician Meguma Group of Nova Scotia. Because of their morphological variability and the absence of previously defined morphotypes, the burrows are unnamed yet do provide a cautionary note to the naming of trace fossils, even at the ichnogeneric level, by ichnologists. The traces record the activity of unknown and mobile deposit-feeding organisms that inhabited interchannel or levee areas immediately adjacent to and up to 5 m laterally from a 2 m deep channel developed on a deep-sea, mid–outer submarine-fan complex. Many of the vertically to subvertically oriented systems penetrate up to 40 cm, suggesting that existing models on the depth of early Palaeozoic benthic boundary layers obtained from shelf environments must be utilized with caution.
Solubilité de l'or dans les eaux interstitielles de la latérite coiffant le gîte aurifère de Misséni, au Mali
Authors: Séa Frédéric , Tanguay Marc G. , Trudel Pierre , Bergeron Mario
Published: October 2017

Twenty samples of interstitial waters and pressed saprolite were collected within undisturbed saprolite blocks to determine the actual gold transporting mode in the auriferous laterites of Misséni, Mali. The results of the analyses indicate a very high solubility of gold in the interstitial waters of the Misséni laterites (from <2 to 16.7 ppb Au; Eh, 0.356–0.419 V; pH, 6.7–7.7). The calculated theoretical concentrations of auric chloride ion, [Formula: see text], (0.3 × 10−14 – 32.7 × 10−4 ppm) and thiosulphate ion, [Formula: see text], (2.5 × 10−212 – 6.7 × 10−180 ppm), which are generally inferred to be the ions transporting the gold in a supergene environment, are insignificant in the interstitial waters of the Misséni saprolite. Given the absence of significant concentrations of chloride or thiosulphate ions as measured in the interstitial waters of Misséni (Cl−, 1.5 × 10−4 – 1.2 × 10−2 mol L−1; [Formula: see text], 1.1 × 10−111 – 4.2 × 10−95 mol L−1), the gold monohydroxide, AuOH(H2O)0, could be responsible for the gold mobilization in the studied saprolite. However, its transport could be limited by the conspicuous (Fe, Mn) oxides in the Misséni saprolite, which can act as adsorbents. The calculated concentrtion of humic acid (0.004–0.03%), which can solubilize the gold contained in the analyzed interstitial waters, is 2 to 4 times lower than that of the measured organic matter in the samples of pressed saprolite (from <0.016 to 0.07% in organic carbon). These latter results could indicate that a part of the gold solubility in the Misséni superficial saprolite is linked to the humic acids. [Journal Translation]
Aphebian mafic–ultramafic magmatism in the Labrador Trough (New Quebec): its age and the nature of its mantle source
Authors: Rohon M. -L. , Vialette Y. , Clark T. , Roger G. , Ohnenstetter D. , Vidal Ph.
Published: October 2017

The magmatic events occurring within the two main cycles in the south-central part of the Labrador Trough (New Quebec) have been dated. In cycle 1, a granophyre dike related to the Cramolet Lake gabbro sill, which intrudes the Seward subgroup, has a U–Pb zircon age of 2169 ± 2 Ma. In cycle 2, the tholeiitic basalts of the Willbob (Hellancourt) Formation and the related mafic–ultramafic sills are dated at ca. 1900 Ma by the Pb–Pb method. These data confirm the existence of at least two main magmatic cycles separated by about 270 Ma. The magma source was depleted upper mantle, and the magma did not experience any significant crustal contamination, as indicated by the μ1 ratio (7.9) and [Formula: see text] (+4) for the tholeiitic basalts. The μ1 value for the intrusive rocks (8.03) and the average [Formula: see text] value for the gabbroic rocks of cycle 2 (+2.8) and for the granophyre of cycle 1 (+1.05) could be the result of slight crustal contamination or of mantle heterogeneity. Whatever the cause of these values, the data indicate the prolonged presence of a depleted mantle source.
Burial and exhumation of the Long Range Inlier and its surroundings, western Newfoundland: results of an apatite fission-track study
Authors: Hendriks M. , Jamieson R. A. , Willett S. D. , Zentilli M.
Published: October 2017

The Long Range Inlier, a steep-sided plateau underlain mainly by Grenvillian gneisses, is the most prominent topographic feature of western Newfoundland. Apatite fission-track analysis of 31 samples from the Long Range Inlier and its surroundings yielded measured apparent ages of 343–152 Ma. Age versus elevation plots, track-length distributions, and model thermal histories indicate that the region experienced slow cooling in the late Paleozoic, with apparent exhumation rates of 7–9 m∙Ma−1 and cooling rates of 0.08–0.28 °C∙Ma−1. Model thermal histories suggest that the present upper surface of the Long Range plateau cooled below ~120 °C in Ordovician times. The thermal histories are compatible with, but do not require, some exhumation of the Long Range Inlier along Acadian thrust faults. Results from Early Carboniferous sedimentary rocks of the Deer Lake Basin are similar to Long Range Inlier data from similar elevations, implying that at some time between ~350 and 300 Ma, the entire region was buried to depths sufficient to induce total annealing (T > 120 °C) in these samples. Closure ages determined from model thermal histories indicate that regional cooling to temperatures below ~120 °C began before 300 Ma. The Carboniferous sedimentary cover was largely removed by Jurassic time, perhaps in response to lowering of regional base level by rifting associated with the opening of the Atlantic Ocean.
A Silurian U–Pb age for the Cape St. Mary's sills, Avalon Peninsula, Newfoundland, Canada: implications for Silurian orogenesis in the Avalon Zone
Authors: Greenough John D. , Kamo Sandra L. , Krogh Thomas E.
Published: October 2017

Mafic sills from Cape St. Mary's on the Avalon Peninsula of Newfoundland give an U–Pb baddeleyite age of 441 ± 2 Ma. This age corresponds with the earliest ages recorded for the climactic Silurian orogenic event that dominantly affected rocks of the Central Mobile Belt in Newfoundland. The age is consistent with but in no way necessitates that the Avalon and Gander zones were juxtaposed during the Silurian. Because sills tend to form in poorly lithified and undeformed sedimentary rocks, it is unlikely that Cambrian sediments hosting the sills were affected by Ordovician orogenic events that strongly affected central Newfoundland. Negative Nb and Ti anomalies on mid-ocean-ridge basalt normalized diagrams show that the sill geochemistry is consistent with formation in a transpressional tectonic environment. Mafic magmas clearly associated with the Silurian event share these chemical and tectonic affinities. Thus both the age and geochemical data are consistent with but do not require a link between the Gander and Avalon zones during the Silurian. If the two zones were joined prior to the Silurian then the Avalon must have been distal to both the Ordovician and Silurian orogenic activity. Further, considerable post-Silurian movement would have had to occur along the bounding Hermitage–Dover fault to account for contrasts in the intensity of metamorphism, plutonism, and deformation between the Gander and Avalon zones.
Multituberculates of the Lac Pelletier Lower Fauna, Late Eocene (Duchesnean), of Saskatchewan
Authors: Storer John E.
Published: October 2017

Two multituberculate taxa (Mammalia: Allotheria) occur in the Lac Pelletier Lower Fauna, Late Eocene (Duchesnean), Swift Current Plateau, Saskatchewan. Ectypodus lovei is known from Uintan to Chadronian faunas of Wyoming, Montana, and Saskatchewan. All Uintan to Chadronian specimens previously identified as Ectypodus sp. are referred to Ectypodus lovei. A second ?neoplagiaulacid, known only from Lac Pelletier, is the largest reported Middle or Late Eocene multituberculate.
Comparison of the Rainy Ridge analcime phonolite sill and the Crowsnest volcanics, Alberta, Canada
Authors: Goble R. J. , Treves S. B. , Ghazi A. M.
Published: October 2017

A 5–7 m thick analcime phonolite sill occurs in the middle of the Proterozoic Gateway Formation in southwest Alberta. The sill consists of sanidine, aegirine–augite, magnesian hastingsite, melanite with hydrogrossular rims, titanite, and minor biotite, apatite, and opaque minerals. Mineralogical and chemical similarities to the analcime-rich phases of the Cretaceous Crowsnest Formation found some 20 km to the north suggest a genetic relationship. Major differences are the presence of amphibole and hydrogrossular, minerals not reported in the Crowsnest Formation. The presence of amphibole as a primary hydrous phase in the Rainy Ridge sill indicates crystallization from a hydrous magma. Microprobe studies indicate a progressive enrichment of sodium in amphiboles and pyroxenes. An apparent difference in chemical composition and alteration behavior of primary analcime phenocrysts and groundmass analcime is interpreted to reflect crystallization of analcime from a hydrous melt at depth, followed by rapid transport to a shallow depth, and crystallization of the groundmass analcime and hydrogrossular rims.
Syntectonic minor intrusions or synemplacement deformation?
Authors: Gower Charles F.
Published: October 2017

The concept of dating deformation using "syntectonic" minor intrusions involves flawed reasoning. At best, the time of a deformational event can only be bracketed, using pre- and postdeformation minor intrusions.
A physical map with yeast artificial chromosome (YAC) clones covering 63% of the 12 rice chromosomes
Authors: Saji Shoko , Umehara Yosuke , Antonio Baltazar A , Yamane Hiroko , Tanoue Hiroshi , Baba Tomoya , Aoki Hiroyoshi , Ishige Naoko , Wu Jianzhong , Koike Kazuhiro , Matsumoto Takashi , Sasaki Takuji
Published: October 2017

A new YAC (yeast artificial chromosome) physical map of the 12 rice chromosomes was constructed utilizing the latest molecular linkage map. The 1439 DNA markers on the rice genetic map selected a total of 1892 YACs from a YAC library. A total of 675 distinct YACs were assigned to specific chromosomal locations. In all chromosomes, 297 YAC contigs and 142 YAC islands were formed. The total physical length of these contigs and islands was estimated to 270 Mb which corresponds to approximately 63% of the entire rice genome (430 Mb). Because the physical length of each YAC contig has been measured, we could then estimate the physical distance between genetic markers more precisely than previously. In the course of constructing the new physical map, the DNA markers mapped at 0.0-cM intervals were ordered accurately and the presence of potentially duplicated regions among the chromosomes was detected. The physical map combined with the genetic map will form the basis for elucidation of the rice genome structure, map-based cloning of agronomically important genes, and genome sequencing.Key words: physical mapping, YAC contig, rice genome, rice chromosomes.
Identification of YAC clones containing the mutable slender glume locus slg in rice (Oryza sativa L.)
Authors: Teraishi M , Hirochika H , Okumoto Y , Horibata A , Yamagata H , Tanisaka T
Published: October 2017

A mutable slender glume gene slg, which often reverts to the wild-type state, was induced by gamma-ray irradiation of seeds of the japonica rice cultivar 'Gimbozu'. The final goal was to understand whether the slender glume mutation was associated with the insertion of a transposable element, utilizing map-based cloning techniques. The RFLP (restriction fragment length polymorphism) analysis revealed that the slg locus was located between two RFLP loci, XNpb33 and R1440, on chromosome 7 with recombination values of 3.1% and 1.0%, respectively. Using these two RFLP loci as probes, five YAC (yeast artificial chromosome) clones containing either of these two loci were selected from a YAC library. Subsequently, both end fragments of these YAC clones, amplified by the inverse PCR (IPCR) method, were used to select new YAC clones more closely located to the slg locus. After repeating such a procedure, we successfully constructed a 6-cM YAC contig, and identified four overlapping YAC clones, Y1774, Y3356, Y5124, and Y5762, covering the slg locus. The chromosomal location of the slg was narrowed down to the region with a physical distance of less than 280 kb between the right-end fragments of Y1774 and Y3356.Key words: Oryza sativa, mutable gene, slender glume mutation, YAC contig.
Random amplified polymorphic DNA diversity of marginal and central populations inPinus contortasubsp.latifolia
Authors: Fazekas Aron J , Yeh Francis C
Published: October 2017

Fifteen populations of lodgepole pine (Pinus contorta subsp. latifolia) were surveyed for diversity across 52 random amplified polymorphic DNAs (RAPDs). The objective was to compare single-locus and multilocus structures in four marginal, three intermediate, and eight central populations. Single-locus estimates indicated average observed and expected heterozygosity to be 0.19 and 0.17, respectively. When these estimates were split into population categories, a clear trend of increasing diversity was detected in the direction of marginal to central populations. F-statistics indicated an excess of heterozygotes, with FISranging from -0.08 for marginal populations to -0.15 for central populations and averaging -0.12 over 15 populations. The estimates of FSTdecreased towards the margins of the species range, indicating increased population differentiation. Forty-nine of 52 RAPDs tested neutral in the Ewens-Watterson analysis. Multilocus analysis showed significant two-locus and high-order gametic disequilibria in all 15 populations. The most prominent components of the two-locus analysis were the variance of disequilibrium (VD, 46.2%) and the multilocus Wahlund effect (31.9%). This high value for VD indicated that founder effects could explain much of the observed multilocus associations. When analyzed by population categories, the VD showed a decreasing trend indicating that variation due to founder effects was more prominent in marginal populations. The two-locus Wahlund effect (WC) that is characteristic of strong population subdivision was highest in the central populations. This indicated significant levels of gene flow between populations with different allelic combinations.Key words: multilocus genetic structure, central and marginal populations, RAPD, Pinus contorta subsp. latifolia.
The porcine gonadotropin-releasing hormone receptor gene (GNRHR): Genomic organization, polymorphisms, and association with the number of corpora lutea
Authors: Jiang Zhihua , Gibson John P , Archibald Alan L , Haley Chris S
Published: October 2017

The interaction of gonadotropin-releasing hormone (GNRH) and its receptor (GNRHR) is critical in the endocrine regulation of reproduction. The gene (GNRHR) encoding the receptor has been mapped to porcine chromosome 8. There is evidence for three quantitative trait loci (QTL) influencing ovulation rate on this chromosome. We obtained an almost complete sequence (3993 bp, excluding intron 1) of the porcine GNRHR gene using PCR-based comparative genomic walking and inverse genomic walking approaches. Twelve polymorphisms were detected by sequencing of pooled DNA of Chinese Taihu and European Large White pigs, including 7 base substitutions and 5 insertions-deletions (indels). A F2population of Meishan × European Large White pigs was genotyped for a TG indel in the promoter region, and a C/G substitution in the 3' UTR (untranslated region). A significant association of the C/G substitution with number of corpora lutea at first parity was observed.Key words: porcine GNRHR, genomic organization, polymorphisms, association, corpora lutea.
Characterization of euploid backcross progenies derived from interspecific hybrids betweenOryza sativaandO. eichingeriby restriction fragment length polymorphism (RFLP) analysis and genomic in situ hybridization (GISH)
Authors: Yan Huihuang , Liu Guoqing , Cheng Zhukuan , Min Shaokai , Zhu Lihuang
Published: October 2017

Restriction fragment length polymorphism (RFLP) analysis and GISH (genomic in situ hybridization) were performed on euploid plants derived from crosses between Oryza sativa (2n = 24, AA) and two brown planthopper-resistant accessions of O. eichingeri (2n = 24, CC). After screening with 164 RFLP markers, 60 of the 67 euploid plants were identified as introgression lines, each carrying 16 small O. eichingeri segments integrated on chromosomes 1, 2, 6, or 10. In the somatic chromosome preparations of F1hybrid, O. eichingeri chromosomes, fluorescing greenish-yellow in the sequential GISH, appeared to be longer and to contain more heterochromatin than O. sativa ones, and this karyotypic polymorphism can be used to detect some introgressed O. eichingeri segments in euploid plants. In addition, GISH identification presented direct evidence for the transfer of small segments from O. eichingeri to O. sativa chromosome(s) which were subsequently recognized according to their condensation pattern, arm ratio, and chromosome length. The present results would contribute to the molecular mapping and selection of O. eichingeri - derived brown planthopper-resistant gene and positive yield QTLs.Key words: Oryza sativa, Oryza eichingeri, introgression lines, RFLP, genomic in situ hybridization (GISH).
Sau3A in situ digestion of human chromosome 3 pericentromeric heterochromatin. I. Differential digestion of α-satellite and satellite 1 DNA sequences
Authors: Buño I , Fernández J L , López-Fernández C , Díez-Martín J L , Gosálvez J
Published: October 2017

In situ digestion with the restriction endonuclease (RE) Sau3A (Sau3A REISD) uncovers a polymorphism for the pericentromeric heterochromatin of human chromosome 3, which can be positively stained (3+) or not (3), and has proven useful to differentiate donor and recipient cells after sex-matched bone marrow transplantation and to analyze the so-called hemopoietic chimerism. The aim of the present investigation was to obtain insight into the molecular basis of such polymorphism to optimize its use for chimerism quantification using methodological approaches other than REISD. To this end, fluorescence in situ hybridization (FISH) assays using probes for the satellite DNA sequences that mainly constitute chromosome 3 pericentromeric heterochromatin (α-satellite and satellite 1 DNA) were performed on control and Sau3A-digested chromosomes. The results obtained suggest that chromosome 3 α-satellite DNA is digested in all individuals studied, irrespective of the karyotype obtained by Sau3A REISD (3++, 3+, 3--), and thus it does not seem to be involved in the polymorphism uncovered by Sau3A on this chromosome. Satellite 1 DNA is not digested in any case, and shows a polymorphism for its domain size, which correlates with the polymorphism uncovered by Sau3A in such a way that 3+ chromosomes show a large domain (3L) and 3 chromosomes show a small domain (3S). It seems, therefore, that the cause of the polymorphism uncovered by Sau3A on the pericentromeric region of chromosome 3 is a difference in the size of the satellite 1 DNA domain. Small satellite 1 DNA domains fall under the resolution level of REISD technique and are identified as 3.Key words: heterochromatin, α-satellite DNA, classical satellite DNA, satellite 1 DNA, restriction endonucleases, FISH.
An efficient method for the physical mapping of transgenes in barley using in situ hybridization
Authors: Salvo-Garrido H , Travella S , Schwarzacher T , Harwood W A , Snape J W
Published: October 2017

The genetic transformation of crops by particle bombardment and Agrobacterium tumefaciens systems have the potential to complement conventional plant breeding programmes. However, before deployment, transgenic plants need to be characterized in detail, and physical mapping is an integral part of this process. Therefore, it is important to have a highly efficient method for transgene detection by fluorescence in situ hybridization (FISH). This study describes a new approach, which provides efficient control of probe length and labelling, both of which play an important role in in situ hybridization of transgenes. The approach is based on reducing the size of the plasmid prior to labelling by nick translation, rather than using the whole or linearized plasmid, or varying the amounts of DNaseI in the nick translation mixture. This provided much more efficient labelling of the probe, which yielded optimal hybridization, minimal fluorescent background, and accurate physical location of the transgene.Key words: barley, transformation, FISH, transgene detection, probe design.
Pattern of X-Y chromosome pairing in the Taiwan vole, Microtus kikuchii
Authors: Mekada K , Harada M , Lin L K , Koyasu K , Borodin P M , Oda S -I
Published: October 2017

Pairing of X and Y chromosomes at meiotic prophase and the G- and C-banding patterns and nucleolar organizer region (NOR) distribution were analyzed in Microtus kikuchii. M. kikuchii is closely related to M. oeconomus and M. montebelli, karyologically and systematically. The formation of a synaptonemal complex between the X and Y chromosomes at pachytene and end-to-end association at diakinesis  metaphase I are only observed in three species in the genus Microtus; M. kikuchii, M. oeconomus, and M. montebelli. All the other species that have been studied so far have had asynaptic XY chromosomes. These data confirm that M. kikuchii, M. oeconomus, and M. montebelli are very closely related, and support the separation of asynaptic and synaptic groups on the phylogenetic tree.Key words: Microtus kikuchii, Microtus phylogeny, karyotype, synaptic sex chromosomes, synaptonemal complex.