Sample records for western canada sedimentary

  1. Assessment of undiscovered conventional oil and gas resources of the Western Canada Sedimentary Basin, Canada, 2012 (United States)

    Higley, Debra


    The U.S. Geological Survey recently completed a geoscience-based assessment of undiscovered oil and gas resources of provinces within the Western Canada Sedimentary Basin. The Western Canada Sedimentary Basin primarily comprises the (1) Alberta Basin Province of Alberta, eastern British Columbia, and the southwestern Northwest Territories; (2) the Williston Basin Province of Saskatchewan, southeastern Alberta, and southern Manitoba; and (3) the Rocky Mountain Deformed Belt Province of western Alberta and eastern British Columbia. This report is part of the U.S. Geological Survey World Petroleum Resources Project assessment of priority geologic provinces of the world. The assessment was based on geoscience elements that define a total petroleum system (TPS) and associated assessment unit(s). These elements include petroleum source rocks (geochemical properties and petroleum generation, migration, and accumulation), reservoir description (reservoir presence, type, and quality), and petroleum traps (trap and seal types, and timing of trap and seal formation relative to petroleum migration). Using this framework, the Elk Point-Woodbend Composite TPS, Exshaw-Fernie-Mannville Composite TPS, and Middle through Upper Cretaceous Composite TPS were defined, and four conventional assessment units within the total petroleum systems were quantitatively assessed for undiscovered resources in the Western Canada Sedimentary Basin.

  2. Biodegradation and origin of oil sands in the Western Canada Sedimentary Basin

    Institute of Scientific and Technical Information of China (English)

    Zhou Shuqing; Huang Haiping; Liu Yuming


    The oil sands deposits in the Western Canada Sedimentary Basin (WCSB) comprise of at least 85% of the total immobile bitumen in place in the world and are so concentrated as to be virtually the only such deposits that are economically recoverable for conversion to oil.The major deposits are in three geographic and geologic regions of Alberta: Athabasca,Cold Lake and Peace River.The bitumen reserves have oil gravities ranging from 8 to 12° API,and are hosted in the reservoirs of varying age,ranging from Devonian (Grosmont Formation) to Early Cretaceous (Mannville Group).They were derived from light oils in the southern Alberta and migrated to the north and east for over 100 km during the Laramide Orogeny,which was responsible for the uplift of the Rocky Mountains.Biodegradation is the only process that transforms light oil into bitumen in such a dramatic way that overshadowed other alterations with minor contributions.The levels of biodegradation in the basin increasing from west (non-biodegraded) to east (extremely biodegraded) can be attributed to decreasing reservoir temperature,which played the primary role in controlling the biodegradation regime.Once the reservoir was heated to approximately 80 ℃,it was pasteurized and no biodegradation would further occur.However,reservoir temperature could not alone predict the variations of the oil composition and physical properties.Compositional gradients and a wide range of biodegradation degree at single reservoir column indicate that the water-leg size or the volume ratio of oil to water is one of the critical local controls for the vertical variations of biodegradation degree and oil physical properties.Late charging and mixing of the fresh and degraded oils ultimately dictate the final distribution of compositions and physical properties found in the heavy oil and oil sand fields.Oil geochemistry can reveal precisely the processes and levels that control these variations in a given field,which opens the

  3. Mass balance and fluid flow constraints on regional-scale dolomitization, Late Devonian, Western Canada Sedimentary Basin

    Energy Technology Data Exchange (ETDEWEB)

    Machel, H.G. [Alberta Univ., Edmonton, AB (Canada); Mountjoy, E.M. [McGill Univ., Montreal, PQ (Canada). Dept. of Earth and Planetary Sciences; Amthor, J.E. [Shell Internationale Research Maatschappij NV, The Hague (Netherlands)


    Flow mechanisms that resulted in regionally pervasive, replacive dolomitization of the Upper Devonian carbonates in the Western Canada Sedimentary Basin (WCSB), were discussed. In critiquing the hydrogeological model proposed by Shields and Brady (1995), these interveners noted three major problems: (1) brine recharge area not isotropic or homogeneous, (2) hydrogeologic model does not match the conceptual geological model, (3) the aspect ratio of the hydrogeologic model is inconsistent with other explanations of brine reflux flushing. While these authors agree that seepage reflux of evaporite brines account for some of the dolomites in the basin, they believe that available geological, petrographic, paragenetic, and geochemical evidence invalidate regional brine reflux as the mechanism of basin-wide pervasive dolomitization, as proposed by Shields and Brady. (A response to this critique from Shields and Brady is presented on pages 572-573 of this issue of the Bulletin). 27 refs., 1 fig.

  4. Implications of Spatial Variability in Heat Flow for Geothermal Resource Evaluation in Large Foreland Basins: The Case of the Western Canada Sedimentary Basin

    Directory of Open Access Journals (Sweden)

    Simon Weides


    Full Text Available Heat flow and geothermal gradient of the sedimentary succession of the Western Canada Sedimentary Basin (WCSB are mapped based on a large thermal database. Heat flow in the deep part of the basin varies from 30 mW/m2 in the south to high 100 mW/m2 in the north. As permeable strata are required for a successful geothermal application, the most important aquifers are discussed and evaluated. Regional temperature distribution within different aquifers is mapped for the first time, enabling a delineation of the most promising areas based on thermal field and aquifer properties. Results of previous regional studies on the geothermal potential of the WCSB are newly evaluated and discussed. In parts of the WCSB temperatures as high as 100–210 °C exist at depths of 3–5 km. Fluids from deep aquifers in these “hot” regions of the WCSB could be used in geothermal power plants to produce electricity. The geothermal resources of the shallower parts of the WCSB (>2 km could be used for warm water provision (>50 °C or district heating (>70 °C in urban areas.

  5. Western Canada SAGD drilling and completions performance

    Energy Technology Data Exchange (ETDEWEB)

    Turchin, S.; Tucker, R. [Ziff Energy Group (Canada)


    In the heavy oil industry, steam assisted gravity drainage (SAGD) is a thermal recovery method used to enhance oil recovery. In 2009, Ziff Energy carried out a study on SAGD drilling and completions performance in Western Canada. This paper presents the methodology used to assess drilling performances and the results obtained. This study was conducted on 159 SAGD well pairs and 1,833 delineation wells in the Western Canadian Sedimentary Basin from late 2004 to fall 2008. The drilling performance assessment was calculated from several aspects including well quality, drilling and completions cost performance and drilling time analysis. This study provided a detailed analysis of drilling and completions costs of SAGD which can help companies to improve their performance.

  6. Sedimentary record from the Canada Basin, Arctic Ocean: implications for late to middle Pleistocene glacial history (United States)

    Dong, Linsen; Liu, Yanguang; Shi, Xuefa; Polyak, Leonid; Huang, Yuanhui; Fang, Xisheng; Liu, Jianxing; Zou, Jianjun; Wang, Kunshan; Sun, Fuqiang; Wang, Xuchen


    Sediment core ARC4-BN05 collected from the Canada Basin, Arctic Ocean, covers the late to middle Quaternary (Marine Isotope Stage - MIS - 1-15, ca. 0.5-0.6 Ma) as estimated by correlation to earlier proposed Arctic Ocean stratigraphies and AMS14C dating of the youngest sediments. Detailed examination of clay and bulk mineralogy along with grain size, content of Ca and Mn, and planktic foraminiferal numbers in core ARC4-BN05 provides important new information about sedimentary environments and provenance. We use increased contents of coarse debris as an indicator of glacier collapse events at the margins of the western Arctic Ocean, and identify the provenance of these events from mineralogical composition. Notably, peaks of dolomite debris, including large dropstones, track the Laurentide Ice Sheet (LIS) discharge events to the Arctic Ocean. Major LIS inputs occurred during the stratigraphic intervals estimated as MIS 3, intra-MIS 5 and 7 events, MIS 8, and MIS 10. Inputs from the East Siberian Ice Sheet (ESIS) are inferred from peaks of smectite, kaolinite, and chlorite associated with coarse sediment. Major ESIS sedimentary events occurred in the intervals estimated as MIS 4, MIS 6 and MIS 12. Differences in LIS vs. ESIS inputs can be explained by ice-sheet configurations at different sea levels, sediment delivery mechanisms (iceberg rafting, suspension plumes, and debris flows), and surface circulation. A long-term change in the pattern of sediment inputs, with an apparent step change near the estimated MIS 7-8 boundary (ca. 0.25 Ma), presumably indicates an overall glacial expansion at the western Arctic margins, especially in North America.

  7. Warm water geothermal and cold energy in western Canada

    Energy Technology Data Exchange (ETDEWEB)

    Peachey, B. [New Paradigm Engineering Ltd., Edmonton, AB (Canada)]|[Petroleum Technology Alliance Canada, Calgary, AB (Canada)


    The Petroleum Technology Alliance of Canada's low carbon futures study was discussed along with a study in which scenarios were developed for three resources, notably bitumen in carbonate reservoirs; conventional heavy oil; and warm water geothermal energy from operating oil wells. The presentation provided an overview of geothermal systems including hot dry rock; dry steam resources; hot water resources; warm water resources; and low temperature systems. A warm water geothermal study for the Western Canada Sedimentary Basin (WCSB) was also presented. Although high quality geothermal energy sources are rare in Canada, there are large warm water geothermal reservoirs, ranging in temperature from 50 to 180 degrees C in the WCSB. This presentation focused on the potential for recovery of the warm water geothermal energy already being brought to surface from the WCSB's oil wells. Several energy approaches were also presented, such as warm geothermal or produced water being used for heating an oil reservoir; using produced mechanical energy for field pumping; and producing renewable electricity from binary plants with propane. Illustrations were also provided for the organic Rankine cycle; low pump geothermal power; and no pump geothermal system. Combined geothermal and oil production were also discussed. Other topics that were presented included industrial cooling; municipal cooling; mined oilsands barriers and tailings; containment of in-situ oilsands; and rural freeze desalination. The report concluded with discussions of the Canadian minerals industry; cold Arctic construction; and ice roads in the North. It was concluded that there is potential for warm water geothermal in existing oilfield operations in Canada. tabs., figs.

  8. Managing the Cumulative Impacts of Land Uses in the Western Canadian Sedimentary Basin: A Modeling Approach

    Directory of Open Access Journals (Sweden)

    Richard, R. Schneider


    Full Text Available This case study from northeastern Alberta, Canada, demonstrates a fundamentally different approach to forest management in which stakeholders balance conservation and economic objectives by weighing current management options from the point of view of their long-term effects on the forest. ALCES®, a landscape-scale simulation model, is used to quantify the effects of the current regulatory framework and typical industrial practices on a suite of ecological and economic indicators over the next 100 yr. These simulations suggest that, if current practices continue, the combined activities of the energy and forestry industries in our 59,000 km2 study area will cause the density of edge of human origin to increase from 1.8 km/km 2 to a maximum of 8.0 km/km2. We also predict that older age classes of merchantable forest stands will be largely eliminated from the landscape, habitat availability for woodland caribou will decline from 43 to 6%, and there will be a progressive shortfall in the supply of softwood timber beginning in approximately 60 yr. Additional simulations involving a suite of "best practices" demonstrate that substantial improvements in ecological outcome measures could be achieved through alternative management scenarios while still maintaining a sustainable flow of economic benefits. We discuss the merits of our proposed approach to land use planning and apply it to the Western Canadian Sedimentary Basin.

  9. Sedimentary processes and depositional environments of the Horn River Shale in British Columbia, Canada (United States)

    Yoon, Seok-Hoon; Koh, Chang-Seong; Joe, Young-Jin; Woo, Ju-Hwan; Lee, Hyun-Suk


    The Horn River Basin in the northeastern British Columbia, Canada, is one of the largest unconventional gas accumulations in North America. It consists mainly of Devonian shales (Horn River Formation) and is stratigraphically divided into three members, the Muskwa, Otterpark and Evie in descending order. This study focuses on sedimentary processes and depositional environments of the Horn River shale based on sedimentary facies analysis aided by well-log mineralogy (ECS) and total organic carbon (TOC) data. The shale formation consists dominantly of siliceous minerals (quartz, feldspar and mica) and subordinate clay mineral and carbonate materials, and TOC ranging from 1.0 to 7.6%. Based on sedimentary structures and micro texture, three sedimentary facies were classified: homogeneous mudstone (HM), indistinctly laminated mudstone (ILM), and planar laminated mudstone (PLM). Integrated interpretation of the sedimentary facies, lithology and TOC suggests that depositional environment of the Horn River shale was an anoxic quiescent basin plain and base-of-slope off carbonate platform or reef. In this deeper marine setting, organic-rich facies HM and ILM, dominant in the Muskwa (the upper part of the Horn River Formation) and Evie (the lower part of the Horn River Formation) members, may have been emplaced by pelagic to hemipelagic sedimentation on the anoxic sea floor with infrequent effects of low-density gravity flows (turbidity currents or nepheloid flows). In the other hand, facies PLM typifying the Otterpark Member (the middle part of the Horn River Formation) suggests more frequent inflow of bottom-hugging turbidity currents punctuating the hemipelagic settling of the background sedimentation process. The stratigraphic change of sedimentary facies and TOC content in the Horn River Formation is most appropriately interpreted to have been caused by the relative sea-level change, that is, lower TOC and frequent signal of turbidity current during the sea

  10. Stress Map 2.0: Updating the Stress Map of the Western Canadian Sedimentary Basin (United States)

    Mallyon, D.; Schmitt, D. R.; Currie, C. A.; Gu, Y. J.; Heidbach, O.


    The greatest horizontal compression in much of the Western Canada Sedimentary Basin appears to uniformly trend NE-SW. Beyond this, major gaps remain in our knowledge of stress magnitudes and even faulting regimes. This lack of quantitative information impedes a proper understanding of seismic events that appear to be linked to hydraulic fracturing stimulations. Apart from this immediate concern, such seismicity could impact long term green-house gas sequestration and geothermal energy development. As part of the Helmholtz-Alberta geothermal collaboration, we are developing a program to update this crustal stress state information. The program consists of more immediate studies related to conventional analysis of borehole image logs, core fractures, and transient pressure records as can be made available. Data sets analyzed to date include logs to 3.5 km depth from areas experiencing induced seismicity, from 2.5 km depth within the Precambrian craton in NE Alberta, and to 400 m depth within a large carbonate platform. All these data largely confirm the NE-SW stress directions. In some cases, the configurations of drilling induced tensile fractures and borehole breakouts allow the faulting regime to be constrained. The addition of new seismometers to the region is also allowing for the refinement of earthquake focal mechanisms. Finally, a dramatic contrast in lithosphere thickness, composition and geothermal gradient exists at the contact between the Cordillera and the North American craton; therefore, lithosphere-scale numerical models are also being developed to quantify the relative contribution of geodynamic processes, such as mantle flow and contact geometry, to the observed stress regime within the basin.

  11. Distinguishing phosphate from fertilizers and wastewater treatment plant effluents in Western Canada using oxygen isotope measurements (United States)

    Fau, Veronique; Nightingale, Michael; Tamburini, Frederica; Mayer, Bernhard


    The successful application of oxygen isotope ratios as a tracer for phosphate in aquatic ecosystems requires that different sources of phosphate are isotopically distinct. The objective of this study was to determine whether the oxygen isotope ratios of phosphate from fertilizers and effluents from wastewater treatment plants in Western Canada are isotopically distinct. Therefore, we carried out oxygen isotope analyses on phosphate in effluent from five different wastewater treatment plants (WWTP) in the Bow River watershed of Alberta, Canada. Samples were collected directly from the final effluent (post-UV) in Banff and Canmore upstream of Calgary, and from effluents of Calgary's WWTPs at Bonnybrook, Fish Creek and Pine Creek. We also carried out oxygen isotope analyses on a variety of phosphate-containing fertilizers that are widely used in Western Canada. Historically, most of the phosphate contained in manufactured fertilizers sold in Alberta came from two distinct deposits: 1) a weathered Pliocene igneous carbonatite located in eastern Canada, and 2) the Permian Phosphoria Formation in the western USA. Phosphate (PO43-) contained in the water or the fertilizer was concentrated and quantitatively converted to pure silver phosphate (Ag3PO4). The silver phosphate was then reduced with carbon in an oxygen free environment using a TC/EA pyrolysis reactor linked to a mass spectrometer where 18O/16O ratios of CO were measured in continuous flow mode. Preparation of samples for δ18OPO4 analyses was conducted using the Magnesium Induced Coprecipitation (MAGIC) method. Expected oxygen isotope ratios for phosphate in equilibrium with water (δ18Oeq) were calculated using the Longinelli and Nuti equation: T (° C) = 111.4 - 4.3 (δ18Oeq - δ18Owater). Measured δ18O values of phosphate for fertilizer samples varied from 8 to 25 oÈ®n average, fertilizer samples of sedimentary origin had higher δ18O values (15.8) than those of igneous origin (11.5). Phosphate isotopic

  12. Compositions and greenhouse gas emission factors of flared and vented gas in the Western Canadian Sedimentary Basin. (United States)

    Johnson, Matthew R; Coderre, Adam R


    A significant obstacle in evaluating mitigation strategies for flaring and venting in the upstream oil and gas industry is the lack of publicly available data on the chemical composition of the gas. This information is required to determine the economic value of the gas, infrastructure and processing requirements, and potential emissions or emissions credits, all of which have significant impact on the economics of such strategies. This paper describes a method for estimating the composition of solution gas being flared and vented at individual facilities, and presents results derived for Alberta, Canada, which sits at the heart of the Western Canadian Sedimentary Basin. Using large amounts of raw data obtained through the Alberta Energy Resources Conservation Board, a relational database was created and specialized queries were developed to link production stream data, raw gas samples, and geography to create production-linked gas composition profiles for approximately half of the currently active facilities. These were used to create composition maps for the entire region, to which the remaining facilities with unknown compositions were geographically linked. The derived data were used to compute a range of solution gas composition profiles and greenhouse gas emission factors, providing new insight into flaring and venting in the region and enabling informed analysis of future management and mitigation strategies. Accurate and transparent determination of environmental impacts of flaring and venting of gas associated with oil production, and potential benefits of mitigation, is severely hampered by the lack of publicly available gas composition data. In jurisdictions within the Western Canadian Sedimentary Basin, frameworks exist for regulating and trading carbon offset credits but current potential for mitigation is limited by a lack of standardized methods for calculating CO2 equivalent emissions. The composition and emission factor data derived in this paper

  13. Drought causes reduced growth of trembling aspen in western Canada. (United States)

    Chen, Lei; Huang, Jian-Guo; Alam, Syed Ashraful; Zhai, Lihong; Dawson, Andria; Stadt, Kenneth J; Comeau, Philip G


    Adequate and advance knowledge of the response of forest ecosystems to temperature-induced drought is critical for a comprehensive understanding of the impacts of global climate change on forest ecosystem structure and function. Recent massive decline in aspen-dominated forests and an increased aspen mortality in boreal forests have been associated with global warming, but it is still uncertain whether the decline and mortality are driven by drought. We used a series of ring-width chronologies from 40 trembling aspen (Populus tremuloides Michx.) sites along a latitudinal gradient (from 52° to 58°N) in western Canada, in an attempt to clarify the impacts of drought on aspen growth by using Standardized Precipitation Index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI). Results indicated that prolonged and large-scale droughts had a strong negative impact on trembling aspen growth. Furthermore, the spatiotemporal variability of drought indices is useful for explaining the spatial heterogeneity in the radial growth of trembling aspen. Due to ongoing global warming and rising temperatures, it is likely that severer droughts with a higher frequency will occur in western Canada. As trembling aspen is sensitive to drought, we suggest that drought indices could be applied to monitor the potential effects of increased drought stress on aspen trees growth, achieve classification of eco-regions and develop effective mitigation strategies to maintain western Canadian boreal forests. © 2017 John Wiley & Sons Ltd.

  14. Electrical conductivity in the precambrian lithosphere of western canada (United States)

    Boerner; Kurtz; Craven; Ross; Jones; Davis


    The subcrustal lithosphere underlying the southern Archean Churchill Province (ACP) in western Canada is at least one order of magnitude more electrically conductive than the lithosphere beneath adjacent Paleoproterozoic crust. The measured electrical properties of the lithosphere underlying most of the Paleoproterozoic crust can be explained by the conductivity of olivine. Mantle xenolith and geological mapping evidence indicate that the lithosphere beneath the southern ACP was substantially modified as a result of being trapped between two nearly synchronous Paleoproterozoic subduction zones. Tectonically induced metasomatism thus may have enhanced the subcrustal lithosphere conductivity of the southern ACP.

  15. A Brief Review of Bovine Coccidiosis in Western Canada (United States)

    Radostits, O. M.; Stockdale, P. H. G.


    Coccidiosis of beef cattle, in both its enteric and nervous forms, seen in feedlots in Western Canada is discussed. Cases of coccidiosis accompanied by nervous signs, occasionally up to 30% of those affected enterically, are most common during the coldest winter months. The pathogenesis of the nervous form of the disease is unknown. Clinical management of disease outbreaks using various chemotherapeutics is described. The importance of using anticoccidial drugs before the onset of clinical signs in cattle in contact with sick animals is discussed. PMID:7000331

  16. High resolution model studies of transport of sedimentary material in the south-western Baltic (United States)

    Seifert, Torsten; Fennel, Wolfgang; Kuhrts, Christiane


    The paper presents high resolution model simulations of transport, deposition and resuspension of sedimentary material in the south-western Baltic, based on an upgrade of the sediment transport model described in the work of Kuhrts et al. [Kuhrts, C., Fennel, W., Seifert, T., 2004. Model studies of transport of sedimentary material in the Western Baltic. Journal of Marine Systems 52, 167.]. In the western Baltic, a grid spacing of at least 1 nautical mile is required to resolve the shallow and narrow bathymetry and the associated current patterns. A series of experimental model simulations is carried out with forcing data for the year 1993, which include a sequence of storms in January. Compared to earlier model versions, a more detailed description of potential deposition areas can be provided. The study quantifies the influence of enhanced bottom roughness caused by biological structures, like mussels and worm holes, provides estimates of the regional erosion risks for fine grained sediments, and analyses scenarios of the settling and spreading of material at dumping sites. Although the effects of changed bottom roughness, as derived from more detailed, re-classified sea floor data, are relatively small, the sediment transport and deposition patterns are clearly affected by the variation of the sea bed properties.

  17. Alberta, Western Canada and the FTA/NAFTA: 1988-95

    Energy Technology Data Exchange (ETDEWEB)

    Janzen, S.S.; Chambers, E.J.


    The sharp improvement in the export performance of Western Canada in recent years was discussed. In 1995, British Columbia ranked first among western provinces in the value of exports, and Alberta ranked second. Shipments from Alberta increased 15.4 per cent in value over 1994. The two provinces account for approximately 80 per cent of Western Canada`s total. A summary was provided of the increased value of exports for certain categories (meat, vegetables, energy, plastics, wood, electrical machinery, furniture, precision instruments); all of these meet the criteria defined for `sustained growth` and `export foothold`. Western Canada`s trade with Mexico was also discussed. All exports from Western Canada were itemized,along with export and U.S. market shares data from 1988 to 1995. 11 tabs.

  18. Fault activation by hydraulic fracturing in western Canada (United States)

    Bao, Xuewei; Eaton, David W.


    Hydraulic fracturing has been inferred to trigger the majority of injection-induced earthquakes in western Canada, in contrast to the Midwestern United States, where massive saltwater disposal is the dominant triggering mechanism. A template-based earthquake catalog from a seismically active Canadian shale play, combined with comprehensive injection data during a 4-month interval, shows that earthquakes are tightly clustered in space and time near hydraulic fracturing sites. The largest event [moment magnitude (MW) 3.9] occurred several weeks after injection along a fault that appears to extend from the injection zone into crystalline basement. Patterns of seismicity indicate that stress changes during operations can activate fault slip to an offset distance of >1 km, whereas pressurization by hydraulic fracturing into a fault yields episodic seismicity that can persist for months.

  19. Long-distance induced tremor observed off western Canada (United States)

    Schultz, Colin


    Using seismic observations made near the Queen Charlotte Margin (QCM), a seismically active region off the western coast of Canada, Aiken et al. add to the growing body of research on how large earthquakes can cause tectonic plates to slip half way around the world. Reaching north from the intersection of the Juan de Fuca ridge, the Cascadia subduction zone, and the Queen Charlotte Fault, QCM underlies the islands of Haida Gwaii and was the site of a magnitude 7.7 earthquake in October 2012. Drawing on seismic readings collected from 1990 to 2012 and using a database of major worldwide earthquakes, the authors identified three earthquakes that induced tremors in QCM: the 2002 magnitude 7.9 Denali earthquake, the 2004 magnitude 9.2 Sumatra quake, and the 2011 magnitude 9.1 Tohoku earthquake. The authors observed the induction not of conventional earthquakes but of deep tectonic tremors, slips of tectonic plates with epicenters located far beneath the surface.

  20. Time dependent seismicity along the western coast of Canada

    Directory of Open Access Journals (Sweden)

    Evangelos V. Christou


    Full Text Available Decelerating generation of intermediate magnitude earthquakes (preshocks in a narrow region (seismogenic region and accelerating generation of relatively larger such earthquakes in a broader region (critical region has been proposed as an appropriate model for intermediate-term earthquake prediction. We examined the seismic activity which preceded the Mw=7.7 (October 28, 2012 thrust event that occurred off the west coast of Haida Gwaii, Canada (formerly the Queen Charlotte islands, by applying the decelerating-accelerating seismic strain model. We found that this mainshock was preceded by a pronounced accelerating seismic sequence with the time to the mainshock, as well as by an equally easily identifiable decelerating seismic sequence. Both precursory seismic sequences occurred in different space, time and magnitude windows. The behavior of previous mainshocks that occurred close to the 2012 earthquake was also examined by the time and magnitude predictable regional model. An attempt was also made to identify such seismic strain patterns, which may also be related to the generation of strong mainshocks along the western coast of Canada.

  1. Glacier and hydrology changes in future climate over western Canada (United States)

    Winger, Katja; Sushama, Laxmi; Marshall, Shawn


    Glaciers are frozen fresh water reservoirs that respond to changes in temperature and snowfall. Concern is growing about the impact that changes in glaciers may have on water resources in regions such as western Canada that derive a lot of their summer streamflow from glacier melt. Given that RCM projections are an important tool and are increasingly being used in assessing projected changes to water resources, particularly due to its high resolution compared with GCMs, realistic representation of glaciers in RCMs is very important. Currently, glaciers are only represented in an extremely simplified way in the fifth generation Canadian Regional Climate Model (CRCM5). This simple approach of representing glaciers as static glacier masks is appropriate for short-term integrations, where the response of glacier to changing atmospheric conditions might still be small due to glacier response times and therefore the feedback of changing glacier extent on large-scale atmospheric flow conditions might be negligible. A new dynamic glacier scheme has been developed for use within CRCM5, based on volume-area relationships. Simulations have been performed with this glacier model and Land Surface Scheme CLASS for the 2000-2100 period over a domain covering western Canada. These simulations were driven by outputs from a CRCM5 transient climate change simulation driven by CanESM2 at the lateral boundaries, for RCPs 4.5 and 8.5. Preliminary results suggest significant decreases to glacier fractions in future climate. Though the glacier contribution to streamflows is found to dramatically decrease in future climate, the total streamflows did not show any dramatic decreases due to the increase in precipitation for these regions.

  2. Tourism Standards: Western Canada. Certification Field Test. Final Report. Formative Evaluation. (United States)

    Alberta Tourism Education Council, Edmonton.

    The Tourism Standards Consortium (TSC) is a partnership of the governments of Canada's western provinces (Alberta, Manitoba, Saskatchewan, and British Columbia), the provinces' tourism industries, and the Pacific Rim Institute of Tourism in British Columbia. In an effort to increase professionalism in Western Canada's tourism industry, the TSC…

  3. Echinococcus multilocularis and Echinococcus canadensis in wolves from western Canada. (United States)

    Schurer, Janna M; Gesy, Karen M; Elkin, Brett T; Jenkins, Emily J


    Echinococcus species are important parasites of wildlife, domestic animals and people worldwide; however, little is known about the prevalence, intensity and genetic diversity of Echinococcus tapeworms in Canadian wildlife. Echinococcus tapeworms were harvested from the intestines of 42% of 93 wolves (Canis lupus) from five sampling regions in the Northwest Territories, Manitoba and Saskatchewan, and visually identified to genus level by microscopic examination. Genetic characterization was successful for tapeworms from 30 wolves, and identified both Echinococcus canadensis and Echinococcus multilocularis in all sampling locations. Mixed infections of E. canadensis/E. multilocularis, as well as the G8/G10 genotypes of E. canadensis were observed. These findings suggest that wolves may be an important definitive host for both parasite species in western Canada. This represents the first report of wolves naturally infected with E. multilocularis in North America, and of wolves harbouring mixed infections with multiple species and genotypes of Echinococcus. These observations provide important information regarding the distribution and diversity of zoonotic species of Echinococcus in western North America, and may be of interest from public health and wildlife conservation perspectives.

  4. The potential for western Canada to become a leader in electrically powered land transport

    Energy Technology Data Exchange (ETDEWEB)

    Perl, A.; Gilbert, R. [Simon Fraser Univ., Burnaby, BC (Canada)


    Canada's western provinces are among the most oil-intensive jurisdictions in the world. Per capita consumption in 2007 was 70 percent higher than that of eastern Canada. While western Canada will be buffered as a producer of oil, predicted swings in oil prices may disrupt the fiscal capacity of producer provinces. The price of crude oil in western Canada is the same price established in world markets. This paper examined some of the opportunities available for western Canada to move away from oil consumption by becoming a leader in electric traction. Methods of replacing oil-based transportation with the use of electric vehicles were discussed. Western Canada's capacity to produce electricity from renewable resources was evaluated. Economic opportunities related to the electrification of land transport were also examined. The report concluded by stating that a clear vision and policy framework for supporting new technologies for surface transport across western Canada are needed. 72 refs., 4 figs.

  5. Geophysical anatomy of counter-slope scarps in sedimentary flysch rocks (Outer Western Carpathians) (United States)

    Tábořík, P.; Lenart, J.; Blecha, V.; Vilhelm, J.; Turský, O.


    A multidisciplinary geophysical survey, consisting of electrical resistivity tomography (ERT), ground penetrating radar (GPR), shallow seismic refraction (SSR) and gravity survey (GS), was used to investigate the counter-slope scarps, one of the typical manifestations of the relaxed zones of rock massifs, and the possible initial stages of deep-seated landslides (DSLs). Two upper parts of the extensive DSLs within the Moravskoslezské Beskydy Mountains (Outer Western Carpathians - OWC) built by the sedimentary flysch rock were chosen as the testing sites. A combined geophysical survey on the flysch rocks was performed on both localities to enhance our present findings. The survey revealed that the ERT is able to reliably detect underground discontinuities, which are manifested at the ground surface by one of the typical landforms (tension cracks, trenches, pseudokarst sinkholes, double-crested ridges and counter-slope scarps). Previous studies suggested that bedrock discontinuities should be depicted by high-resistivity features within ERT surveying. According to SSR and GS, expected zones of weakened rock massif were not confirmed directly underneath the superficial landforms, but they were shifted. Based on the SSR and GS measurements, the depicted high-contrast transitions between high- and low-resistivity domains within the ERT profiles were newly identified as possible manifestation of bedrock discontinuities. The results of GPR measurements give only limited information on the sedimentary flysch rocks, due to shallow penetrating depth and locally strong signal attenuation. The combined results of multidisciplinary geophysical surveying confirmed an importance of employing more than one geophysical technique for integrated interpretations of measured data. Integrated interpretations of the measured geophysical data provided a new insight into massif disintegration and the geomorphic origin of the landforms related to the DSL.

  6. Sedimentary Basins in the Western White Nile, Sudan, as Indicated by a Gravity Survey

    Institute of Scientific and Technical Information of China (English)


    An academic geophysical research as a regional gravity survey was made during 1994 in the Western White Nile to infer the shallow crustal structures in the area. The result of the survey was compiled as a Bouguer anomaly map with a contour interval of 2 ×10-5m/s2. It is found that the negative residual anomalies are related to the Upper Cretaceous sediments (Nubian Sandstone Formation) filling all depressions in the Basement complex surface while the positive residual anomalies are attributed to the relatively shallow or outcropping Basement rocks and the steep gravity gradients are resulting from the sharp contacts between the sedimentary infill and the Basement rocks. To define the geological structures in the area, 9 profiles were studied. For each of the profiles, measured and computed Bouguer gravity anomalies, crustal density model, subsurface geology evaluation were performed. A G-model computer program was applied in the gravity modeling, which is based on the line-integral method of gravity computation. A geological/structural map was proposed showing inferred sedimentary basins, faulting troughs and uplifted Basement block and tectonic trends. The basins are believed to be fault-controlled which developed by extensional tectonics (pull-apart mechanism). As for the mechanism and cause of faulting, the area is considered as a part of the Central Sudan rift system which had been subjected to several tectonic events since Early Cambrian to Tertiary times which resulted in the formation of several fracture systems associated with block subsidence, rifting and basin formation.

  7. Geochemical Analysis for Sedimentary Emerald Mineralization in Western Emerald belt, Colombia (United States)

    Nino Vasquez, Gabriel Felipe; Song, Sheng-Rong


    1Gabriel Felipe Nino Vasquez and 1Sheng-Rong Song 1Department of Geosciences, National Taiwan University Colombia hosts a large quantity of mineral resources due to its complex tectonic arrangement, and emerald deposits are one of the most representatives for the country. Emeralds in Colombia occur mainly in black shale, and are located in eastern Andes Cordillera with two parallel belts separated by approximately 130 Km: the Western belt (WB) and the Eastern belt (EB). The geological, mineralogical and tectonic features from these belts are quite similar (Buenaventura 2002). Previous researchers concluded that emeralds in Colombia came from hydrothermal sedimentary processes without any magmatic influence, and suggested that the source of Cr, V and Be (which are important components of the beryl) was the host rock. According to their results, the process which allowed the shale to release these cations was the metasomatism (albitization and carbonization), which was resulted from the interaction between the rocks and the alkaline brines. Fractures and fault planes originated by these tectonic movements were fulfilled by enriched fluids, which they allowed emeralds and the other minerals precipitation with decreasing alkalinity and pressure (Giuliani et al. 1994). However, there were several pitfalls of conclusions drawn from previous researches. Firstly, Cr and V were widely distributed and come from mafic and ultramafic rocks, and Be was mostly found in pegmatites, finding these elements in sedimentary rocks suggest that probably the ultramafic rocks occurred not far from the deposits. Secondly, there was an inconsistency in the estimated temperatures of emeralds formation, i.e. temperature of hydrothermal sedimentary deposits was only 200° C, while laboratory analysis showed that the formation of emeralds was higher than 300° C. Therefore, there might still be an allocthonus influence on emerald formation that significantly increases the temperature. This

  8. Baseline (1961-1990) average air temperature (degree C) for Alaska and Western Canada. (United States)

    Arctic Landscape Conservation Cooperative — Baseline (1961-1990) average air temperature (degree C) for Alaska and Western Canada. Baseline results for 1961-1990 are derived from Climate Research Unit (CRU)...

  9. Sage-grouse Management Zones in the Western U.S. and Canada - DRAFT (United States)

    U.S. Geological Survey, Department of the Interior — This data set depicts a preliminary version of the management zone boundaries for Greater and Gunnison sage-grouse in the western United States and Canada. These...

  10. Baseline (1961-1990) average air temperature (degree F) for Alaska and Western Canada. (United States)

    Arctic Landscape Conservation Cooperative — Baseline (1961-1990) average air temperature (degree F) for Alaska and Western Canada. Baseline results for 1961-1990 are derived from Climate Research Unit (CRU) TS...

  11. Reconstructing a mid-Cretaceous landscape from paleosols in western Canada (United States)

    Ufnar, David F.; Gonzalez, Luis A.; Ludvigson, Greg A.; Brenner, Richard L.; Witzke, B.J.; Leckie, D.


    The Albian Stage of the mid-Cretaceous was a time of equable climate conditions with high sea levels and broad shallow epeiric seas that may have had a moderating affect on continental climates. A Late Albian landscape surface that developed during a regression and subsequent sea-level rise in the Western Canada Foreland Basin is reconstructed on the basis of correlation of paleosols penetrated by cores through the Paddy Member of the Peace River Formation. Reconstruction of this landscape refines chronostratigraphic relationships and will benefit future paleoclimatological studies milizing continental sphaerosiderite proxy records. The paleosols developed in estuarine sandstones and mudstones, and they exhibit evidence of a polygenetic history. Upon initial exposure and pedogenesis, the Paddy Member developed deeply weathered, well-drained cumulative soil profiles. Later stages of pedogenesis were characterized by hydromorphic soil conditions. The stages of soil development interpreted for the Paddy Member correlate with inferred stages of pedogenic development in time-equivalent formations located both basinward and downslope (upper Viking Formation), and landward and upslope (Boulder Creek Formation). On the basis of the genetic similarity among paleosols in these three correlative formations, the paleosols are interpreted as having formed along a single, continuous landscape surface. Results of this study indicate that the catena concept of pedogenesis along sloping landscapes is applicable to ancient successions. Sphaerosiderites in the Paddy Mem ber paleosols are used to provide proxy values for meteoric ??18O values at 52?? N paleolatitude in the Cretaceous Western Interior Basin. The meteoric ??18O values are used to refine existing interpretations about the mid-Cretaceous paleolatitudinal gradient in meteoric ?? 18O values, and the mid-Cretaceous hydrologic cycle. Copyright ?? 2005, SEPM (Society for Sedimentary Geology).

  12. Sedimentary Markers : a window into deep geodynamic processes Examples from the Western Mediterranean Sea (United States)

    Rabineau, Marina; Aslanian, Daniel; Leroux, Estelle; Pellen, Romain; Gorini, Christian; Moulin, Maryline; Droz, Laurence; Bache, Francois; Molliex, Stephane; Silenzario, Carmine; Rubino, Jean-Loup


    Deep Earth dynamics impact so strongly on surface geological processes that we can use sediment palaeo-markers as a window into the deeper Earth. Derived from climatic and tectonic erosive actions on the continents, and related to eustasy, subsidence and isostasy, the sediment in a deep basin is the main recorder of these processes. Nevertheless, defining and quantifying the relative roles of parameters that interact to give the final sedimentary architecture is not a simple task. Using a 3D-grid of seismic and wide-angle data, boreholes and numerical stratigraphic modelling, we propose here a quantification of post-rift vertical movements in the Provençal Basin (Western Mediterranean) involving three domains of subsidence: seaward tilting on the platform and the slope and purely vertical subsidence in the deep basin (Rabineau et al., 2014 ; Leroux et al., 2015). These domains fit the deeper crustal domains highlighted by previous geophysical data (Moulin et al., 2015 ; Afilhado et al., 2015). Post-break-up sedimentary markers may therefore be used to identify the initial hinge lines of the rifting phase, to quantify sedimentation rates and isostatic rebound (Rabineau et al., 2014) and redefine the subsidence laws. Similar work and results are obtained in the Valencia Basin (Pellen et al., 2016). This Western Mediterranean Sea is a natural laboratory with very high total subsidence rates that enable high sedimentation rates along the margin with sediments provided by the Rhône and Ebro rivers flowing from the Alps, the Pyrennees and Catalan chains, which in turn archives the detailed record of climate/tectonic evolution during the Neogene. The Western Mediterranean Sea could therefore further probe deep-earth and surface connections using deep drillings of this land-locked ocean basin transformed into a giant saline basin (Rabineau et al., 2015). Leroux, E., Aslanian, D., Rabineau, M., M. Moulin, D. Granjeon, C. Gorini, L. Droz, 2015. Sedimentary markers: a

  13. Late Miocene sedimentary environments in south-western Amazonia (Solimões Formation; Brazil). (United States)

    Gross, Martin; Piller, Werner E; Ramos, Maria Ines; Douglas da Silva Paz, Jackson


    In Miocene times a vast wetland existed in Western Amazonia. Whereas the general development of this amazing ecosystem is well established, many questions remain open on sedimentary environments, stratigraphical correlations as well as its palaeogeographical configuration. Several outcrops located in a barely studied region around Eirunepé (SW Amazonas state, Brazil) were investigated to obtain basic sedimentological data. The observed deposits belong to the upper part of the Solimões Formation and are biostratigraphically dated to the Late Miocene. Vertically as well as laterally highly variable fine-grained clastic successions were recorded. Based on the lithofacies assemblages, these sediments represent fluvial deposits, possibly of an anastomosing river system. Sand bodies formed within active channels and dominant overbank fines are described (levees, crevasse splays/channels/deltas, abandoned channels, backswamps, floodplain paleosols). Lacustrine environments are restricted to local floodplain ponds/lakes. The mollusc and ostracod content as well as very light δ(18)O and δ(13)C values, measured on ostracod valves, refer to exclusively freshwater conditions. Based on palaeontological and geological results the existence of a long-lived lake ("Lake Pebas") or any influx of marine waters can be excluded for that region during the Late Miocene.

  14. Regional hydrogeology of the Silurian and Ordovician sedimentary rock underlying Niagara Falls, Ontario, Canada (United States)

    Novakowski, Kentner S.; Lapcevic, Patricia A.


    Due to concern over the potential for widespread groundwater contamination in the sedimentary rock underlying the Niagara Falls area, this study was done to investigate the hydrogeology of the Silurian and Ordovician stratigraphy underlying the Upper Niagara River and the Eastern Niagara Peninsula. Seven boreholes (up to 150 m deep) were drilled, instrumented with multiple packer casing, tested for permeability, sampled for inorganic and organic solutes and monitored for hydraulic head to provide data for a conceptual model of regional groundwater flow. Results show that there are at least three distinct groundwater flow regimes in the bedrock. The uppermost regime consists of fracture zones in the Guelph and Lockport Formations, within which hydraulic conductivity, hydraulic head measurements and geochemical analyses indicate active groundwater circulation primarily discharging towards the Niagara Gorge and Escarpment. Underlying the Lockport Formation are an overpressured (high hydraulic head) regime in the Clinton-Upper Cataract-Lower Queenston Formation and an underpressured (low hydraulic head) regime in the Lower Cataract-Upper Queenston Formation. In both regimes, geochemical analyses and permeability measurements indicate very old and saline groundwater which probably has undergone minimal migration since pre-Pleistocene time. The implication based on the study so far, is that potential groundwater contamination below the bottom of the Lockport Formation is probably not significant in the Niagara Falls area except adjacent to the Niagara Gorge where vertical permeability in the lower flow regimes may be enhanced.

  15. Statistical Analysis of Seismicity Associated with Hydraulic Fracturing in Western Canada (United States)

    Shcherbakov, R.; Ghofrani, H.; Kothari, S.; Atkinson, G. M.; Cheadle, B.; Eaton, D. W. S.; Tiampo, K. F.


    The unconventional extraction of shale oil or gas is typically carried out by the subsurface injection of large volumes of fluids. The fluids are used in the process of hydraulic fracturing and subsequent wastewater injection into high volume disposal wells. These operations are usually accompanied by various levels of seismic activity and sometimes result in the occurrence of moderate to large earthquakes. It is suggested that the increase in seismic activity within the central U.S. in the last decade or so is primely associated with large-scale disposal of wastewater. The Western Canada Sedimentary Basin (WCSB) is an active exploration area for the extraction of oil and gas. The average rate of seismicity is lower than in the central U.S., however, there are several active clusters, where in the last 8-10 years, there has been an increase in the occurrence of moderate earthquakes. In this study, we analyze the statistical properties of seismicity associated with the WCSB. We find that the increase in seismicity rate is mostly associated with the hydraulic fracturing operations in several well defined spatial zones. Hydraulic fracturing involves high-pressure injections of fluids and is performed in multiple stages. This is done along horizontal wells which are drilled at average depths of 2 to 3 km. The triggering of large earthquakes is mostly due to injection of fluids into nearby tectonic faults which are close to failure. To model the rate of the occurrence of earthquakes we introduce a modified version of the Epidemic Type Aftershock Sequence model. The earthquake occurrence rate associated with several prominent clusters is characterized by bursts of activity associated with specifics of hydraulic fracturing operations. The proposed model can be used in the probabilistic assessment and mitigation of the risks associated with hydraulic fracturing.

  16. Sedimentary processes in High Arctic lakes (Cape Bounty, Melville Island, Canada): What do sediments really record? (United States)

    Normandeau, Alexandre; Lamoureux, Scott; Lajeunesse, Patrick; Francus, Pierre


    Lacustrine sedimentary sequences can hold a substantial amount of information regarding paleoenvironments, hydroclimate variability and extreme events, providing critical insights into past climate change. The study of lacustrine sediments is often limited to the analysis of sediment cores from which past changes are inferred. However, studies have provided evidence that the accumulation of sediments in lacustrine basins and their distribution can be affected by a wide range of internal and external forcing mechanisms. It is therefore crucial to have a good knowledge of the factors controlling the transport and distribution of sediments in lakes prior to investigating paleoenvironmental archives. To address this knowledge gap, the Cape Bounty Arctic Watershed Observatory (CBAWO), located on southern Melville Island in the Canadian High Arctic, was initiated in 2003 as a long term monitoring site with the aim of understanding the controls over sediment transport within similar paired watersheds and lakes. The East and West lakes have been monitored each year since 2003 to document the role of hydro-climate variability on water column processes and sediment deposition. Moorings recording water electrical conductivity, temperature, density, dissolved oxygen and turbidity, as well as sediment traps were deployed during the active hydrological period (generally May-July). These data were analyzed in combination with hydrological and climatic data from the watersheds. Additionally, a high-resolution bathymetric and sub-bottom survey was completed in 2015 and allowed imaging the lake floor and sub-surface in great detail. This combination of process and lake morphological data are unique in the Arctic. The morphostratigraphic analysis reveals two highly disturbed lake floors, being widely affected by subaqueous mass movements that were triggered during the last 2000 years. Backscatter intensity maps and the presence of bedforms on each delta foresets indicate that

  17. Cenozoic uplift of the Tibetan Plateau: Evidence from the tectonic–sedimentary evolution of the western Qaidam Basin

    Directory of Open Access Journals (Sweden)

    Yadong Wang


    Full Text Available Geologists agree that the collision of the Indian and Asian plates caused uplift of the Tibet Plateau. However, controversy still exists regarding the modes and mechanisms of the Tibetan Plateau uplift. Geology has recorded this uplift well in the Qaidam Basin. This paper analyzes the tectonic and sedimentary evolution of the western Qaidam Basin using sub-surface seismic and drill data. The Cenozoic intensity and history of deformation in the Qaidam Basin have been reconstructed based on the tectonic developments, faults growth index, sedimentary facies variations, and the migration of the depositional depressions. The changes in the sedimentary facies show that lakes in the western Qaidam Basin had gone from inflow to still water deposition to withdrawal. Tectonic movements controlled deposition in various depressions, and the depressions gradually shifted southeastward. In addition, the morphology of the surface structures in the western Qaidam Basin shows that the Cenozoic tectonic movements controlled the evolution of the Basin and divided it into (a the southern fault terrace zone, (b a central Yingxiongling orogenic belt, and (c the northern fold-thrust belt; divided by the XI fault (Youshi fault and Youbei fault, respectively. The field data indicate that the western Qaidam Basin formed in a Cenozoic compressive tectonic environment caused by the India–Asia plate collision. Further, the Basin experienced two phases of intensive tectonic deformation. The first phase occurred during the Middle Eocene–Early Miocene (Xia Ganchaigou Fm. and Shang Ganchaigou Fm., 43.8–22 Ma, and peaked in the Early Oligocene (Upper Xia Ganchaigou Fm., 31.5 Ma. The second phase occurred between the Middle Miocene and the Present (Shang Youshashan Fm. and Qigequan Fm., 14.9–0 Ma, and was stronger than the first phase. The tectonic–sedimentary evolution and the orientation of surface structures in the western Qaidam Basin resulted from the Tibetan

  18. Climatic Redistribution of Canada's Water Resources (CROCWR): An analysis of spatial and temporal hydrological trends and patterns in western Canada (United States)

    Bawden, A. J.; Burn, D. H.; Prowse, T. D.


    Climate variability and change can have profound impacts on the hydrologic regime of a watershed. These effects are likely to be especially severe in regions particularly sensitive to changes in climate, such as the Canadian north, or when there are other stresses on the hydrologic regime, such as may occur when there are large withdrawals from, or land-use changes within, a watershed. A recent report of the Intergovernmental Panel on Climate Change (IPCC) stressed that future climate is likely to accelerate the hydrologic cycle and hence may affect water security in certain locations. For some regions, this will mean enhanced access to water resources, but because the effects will not be spatially uniform, other regions will experience reduced access. Understanding these patterns is critical for water managers and government agencies in western Canada - an area of highly contrasting hydroclimatic regimes and overlapping water-use and jurisdictional borders - as adapting to climate change may require reconsideration of inter-regional transfers and revised allocation of water resources to competing industrial sectors, including agriculture, hydroelectric production, and oil and gas. This research involves the detection and examination of spatial and temporal streamflow trends in western Canadian rivers as a response to changing climatic factors, including temperature, precipitation, snowmelt, and the synoptic patterns controlling these drivers. The study area, known as the CROCWR region, extends from the Pacific coast of British Columbia as far east as the Saskatchewan-Manitoba border and from the Canada-United States international border through a large portion of the Northwest Territories. This analysis examines hydrologic trends in monthly and annual streamflow for a collection of 34 hydrometric gauging stations believed to adequately represent the overall effects of climate variability and change on flows in western Canada by means of the Mann-Kendall non

  19. Skills required of dairy veterinarians in western Canada: A survey of practicing veterinarians


    Luby, Christopher D.; McIntyre, Katelyn; Jelinski, Murray D.


    This study determined skills required of entry-level veterinarians for dairy practice in western Canada and compared mixed and dairy practitioners in the skills that they perform. We surveyed western Canadian veterinarians involved in dairy practice, focusing primarily on clinical activity of respondents. Response rate was 39.4% (281/714). Respondents were classified as either mixed practitioners ( 75% time in dairy practice). For both gr...

  20. Bentonite chemical features as proxy of late Cretaceous provenance changes: A case study from the Western Interior Basin of Canada (United States)

    Fanti, Federico


    Bentonite beds are fairly common in both marine and terrestrial Upper Cretaceous (Campanian-Maastrichtian) deposits of the Western Interior Basin of western Canada and northwestern United States. A detailed stratigraphic, sedimentologic, geochemical (X-ray fluorescence), and mineralogical (X-ray diffraction) study of twenty-one bentonites from the Puskwaskau and Wapiti formations in the Grande Prairie area (west-central Alberta, Canada) is here presented. Major and trace-element concentrations from altered volcanic ashes document the presence in the study area of predominantly trachyandesitic and rhyolitic volcanogenic products, resulted from intense volcanic arc to within-plate pyroclastic activity. Concentration values of high field strength elements (HFSE) and selected large ion lithophile elements (LILE) (e.g. Nb, Zr, Th, and Y) obtained by X-ray fluorescence spectroscopy strongly support the presence of multiple volcanic sources. Integrated paleoenvironmental and geochemical criteria for provenance determination indicate a bimodal occurrence of basic and acid volcanic products interpreted as reflection of source areas characterized by different tectonic setting and magmatic composition. A comparative analysis of geochemical compositions between Grande Prairie bentonites and 30 known volcanic beds from central and southern Alberta, Manitoba and Montana 1. documents a trend toward more acidic and alkali-depleted volcanic products during the late Campanian-early Maastrichtian interval, and 2. suggests a well constrained stratigraphic and geographic subdivision of the non-marine successions of the foreland basin on the basis of geochemical characteristic of volcanic ash beds. Furthermore, geochemical "fingerprints" of several decimeter to meter thick bentonite beds have been coupled with volcanic ash subsurface signature in order to investigate their role as marker beds. This multiple-approach provides a reliable tool for basin-scale identification and correlation

  1. Indigenous knowledge in Canadian science curricula: cases from Western Canada (United States)

    Kim, Mijung


    To enhance Aboriginal students' educational opportunities in sciences, culturally relevant science curriculum has been examined and practiced in Western Canadian science classrooms. This article shares some examples of inclusion of indigenous knowledge in science curricula and discusses the improvement and challenges of culturally relevant science curricula in Canadian contexts.

  2. Peer Collaboration in an English/Chinese Bilingual Program in Western Canada (United States)

    Sun, Maio


    Informed by current notions of dynamic bilingualism and the community of practice (C of P) framework, this study was designed as an ethnographic case study to explore peer collaboration in an English/Chinese bilingual program in a city in Western Canada. The main participants in the study were three Grade 5 English/Chinese bilingual students. The…

  3. The Effect of Climate Change on Optimal Wetlands and Waterfowl Management in Western Canada

    NARCIS (Netherlands)

    Whitey, P.; Kooten, van G.C.


    Warmer temperatures and a decrease in precipitation in the 21st century could severely deplete wetlands in the prairie pothole region of western Canada. In this study, we employ linear regression analysis to determine the casual effect of climate change on wetlands in this region, with temperature,

  4. The Effect of Climate Change on Optimal Wetlands and Waterfowl Management in Western Canada

    NARCIS (Netherlands)

    Whitey, P.; Kooten, van G.C.


    Warmer temperatures and a decrease in precipitation in the 21st century could severely deplete wetlands in the prairie pothole region of western Canada. In this study, we employ linear regression analysis to determine the casual effect of climate change on wetlands in this region, with temperature,

  5. Serologic survey for viral and bacterial infections in western populations of Canada Lynx (Lynx canadensis) (United States)

    Roman Biek; Randall L. Zarnke; Colin Gillin; Margaret Wild; John R. Squires; Mary Poss


    A serologic survey for exposure to pathogens in Canada lynx (Lynx canadensis) in western North America was conducted. Samples from 215 lynx from six study areas were tested for antibodies to feline parvovirus (FPV), feline coronavirus, canine distemper virus, feline calicivirus, feline herpesvirus, Yersinia pestis, and Francisella tularensis. A subset of...

  6. Identification of extreme sedimentary event deposits in Yilan coastal area, Taiwan, and the western coast of Myanmar (United States)

    Tsai, Y. L.; Shyu, J. B. H.; Sawai, Y.; Kunz, A.


    The Yilan Plain in northeastern Taiwan is located west of the Ryukyu Trench. In AD 1771, a M7.4 earthquake occurred near the Ryukyu Trench, and generated a tsunami (the Meiwa Tsunami) with run-up height of more than 30 m on the Ishigaki Island, only 250 km away from the Yilan Plain. Therefore, we suggest that tsunami poses potential threats to the Yilan Plain. Offshore western Myanmar, a M8.5 earthquake occurred in 1762 on the nearby Sunda Trench. The 2004 Sumatra Tsunami also reached approximately 3 m high along the western coast of Myanmar according to local residents. These observations also point out the potential for a future tsunami hazard along the rapidly developing western Myanmar coast. Therefore, we attempted to search for geological record of previous extreme sedimentary events in these two areas in this study. Many previous studies have pointed out that paleo-tsunami deposits are most likely present in inter-ridge lowlands, and have distinctive characteristics such as a coarse sand layer covering soil layers (or other terrestrial facies sediment layers) with a very sharp boundary. Thus we excavated several trenches in our two study areas to observe and record the deposits, collect samples, and use C-14 dating, Cs-137 analyses and diatom analyses to help us understand the age and sedimentary environment of the deposits. In one trench in northern Yilan Plain, we found a 25 cm thick sand layer covering a mud layer with a sharp and horizontal boundary. We infer that this sand layer deposited during a fluvial flooding event. In southern Yilan Plain, we found another sand layer covering a black mud layer with a sharp and irregular boundary. This clearly indicates a high-energy depositional event, but the source of such an event remains unknown. In trenches excavated along the western coast of Myanmar, we found a gray sand layer covering an organic mud layer that has abundant plant debris with a sharp boundary. Thus we infer that the gray sand is also an

  7. Skills required of dairy veterinarians in western Canada: a survey of practicing veterinarians. (United States)

    Luby, Christopher D; McIntyre, Katelyn; Jelinski, Murray D


    This study determined skills required of entry-level veterinarians for dairy practice in western Canada and compared mixed and dairy practitioners in the skills that they perform. We surveyed western Canadian veterinarians involved in dairy practice, focusing primarily on clinical activity of respondents. Response rate was 39.4% (281/714). Respondents were classified as either mixed practitioners ( 75% time in dairy practice). For both groups, individual animal medicine and surgery skills were performed more commonly than herd health skills. The most important skills identified were those required for basic theriogenology, physical examination, treatment of common disorders, and general surgery. These results underscore the continued importance of individual animal skills in food animal practice in western Canada.

  8. Phosphogypsum capping depth affects revegetation and hydrology in Western Canada. (United States)

    Jackson, Mallory E; Naeth, M Anne; Chanasyk, David S; Nichol, Connie K


    Phosphogypsum (PG), a byproduct of phosphate fertilizer manufacturing, is commonly stacked and capped with soil at decommissioning. Shallow (0, 8, 15, and 30 cm) and thick (46 and 91 cm) sandy loam caps on a PG stack near Fort Saskatchewan, Alberta, Canada, were studied in relation to vegetation establishment and hydrologic properties. Plant response was evaluated over two growing seasons for redtop ( L.), slender wheatgrass ( (Link) Malte ex H.F. Lewis), tufted hairgrass ( (L.) P. Beauv.), and sheep fescue ( L.) and for a mix of these grasses with alsike clover ( L.). Water content below the soil-PG interface was monitored with time-domain reflectometry probes, and leachate water quantity and quality at a depth of 30 cm was measured using lysimeters. Vegetation responded positively to all cap depths relative to bare PG, with few significant differences among cap depths. Slender wheatgrass performed best, and tufted hairgrass performed poorly. Soil caps <1 m required by regulation were sufficient for early revegetation. Soil water fluctuated more in shallow than in thick caps, and water content was generally between field capacity and wilting point regardless of cap depth. Water quality was not affected by cap depths ≤30 cm. Leachate volumes at 30 cm from distinct rainfall events were independent of precipitation amount and cap depth. The study period had lower precipitation than normal, yet soil caps were hospitable for plant growth in the first 2 yr of establishment.

  9. Habitat associations with counts of declining Western Grebes in Alberta, Canada

    Directory of Open Access Journals (Sweden)

    Mara E. Erickson


    Full Text Available During the past several decades, numbers of Western Grebes (Aechmophorus occidentalis have declined throughout their breeding and wintering ranges in North America. We estimated Western Grebe abundance and documented habitat factors between 2007 and 2009 from 43 lakes in Alberta, Canada where Western Grebes historically have occurred, to (1 compare Western Grebe abundance with the relative probability of persistence, and (2 identify habitat correlates of grebe abundance. The relative probability of Western Grebe persistence was correlated with abundance in the study area, although only 19% of the variation in persistence probability was explained by abundance. Western Grebe abundance was positively correlated with the shoreline extent of emergent bulrush (Scirpus lacustris, which is consistent with past studies and underlies the importance of protecting emergent vegetation in efforts to conserve Western Grebes. Grebe abundance also was positively correlated with a longer shoreline perimeter, but was inversely correlated with the amount of forested backshore, which occurred on lakes primarily at the northern margins of Western Grebe range. The amount of backshore development was positively associated with Western Grebe abundance, which might reflect a preference for similar lake characteristics by humans and grebes. These relationships are important to consider in the context of implementing and managing recovery of the Western Grebe in Alberta.

  10. P and S Wave Finite-frequency Imaging of the Cordillera-craton Boundary Zone in Western Canada (United States)

    Gu, Y. J.; Chen, Y.; Hung, S. H.


    The Western Canada Sedimentary Basin (WCSB) marks a boundary zone and a strong seismic lateral velocity gradient in the upper mantle between the Precambrian North American craton and the Phanerozoic Cordillera. While much of the tectonic imprints are buried below thick sediments, seismic data coverage in this region has been greatly improved to unravel the underlying structure, owing to a growing number of regional broadband arrays. In this study we conduct a high-resolution survey of the mantle P- and S-wave velocities in the WCSB using a multi-scale parameterization and the finite-frequency theory. Our models suggest respective increases of 4% and 6% of Vp and Vs velocities across the Cordilleran Deformation Front (CDF) toward the craton interior. This sharp gradient resides to the west of the CDF, which may imply the over-thrusting of the crustal terranes of the Cordillera onto the craton edge. Significant along-strike variation in the lithospheric basal geometry and dip could reflect secular tectonic modifications such as episodic shortening/extension and convective erosion. The results of our finite-frequency tomography indicate vertically continuous high velocities at least down to 200 km beneath the crustal domains of the Precambrian Buffalo Head Terrane (BHT), Hearne craton and Medicine Hat Block (MHB). The lithosphere beneath the southern Hearne province could extend down to 280 km, nearly 70 km deeper than those of its neighboring cratons of similar ages. The velocity anomalies and their intricate variations/reversals within the mantle lithosphere may be evidence for a multi-stage formation of western Laurentia during Precambrian plate convergence. On the other hand, destruction processes since formation, e.g., convective removal and thermomagmatic erosion, may also have played key roles in shaping the mantle lithosphere beneath the western margin of the North American craton.

  11. Petrology and mineral chemistry of sedimentary rocks from the Western Solomon Sea (United States)

    Crook, Keith A. W.


    Sedimentary rocks from the northern margin of the Trobriand Platform, the north wall of the New Britain Trench, and the floor of the Solomon Sea Basin are volcaniclastics, mudrocks, and neritic and bathyal limestones. Arc-volcanic debris from calc-alkaline or high-K magmatic sources is present at each locality. A minor metamorphic component occurs at one site on the Trobriand Platform which yielded Early Eocene to Middle Miocene material, and at the New Britain Trench site, which yielded Miocene or older and post-Miocene samples. Solomon Sea Basin samples are mudrocks which are apparently no older than Late Pliocene.

  12. Climate change in the western and northern forests of Canada: Impacts and adaptations

    Energy Technology Data Exchange (ETDEWEB)

    McKinnon, G. A.; Webber, S. L.; MacKendrick, N. A. [Natural Resources Canada, Canadian Forest Service, Northern Forestry Centre, Edmonton, AB (Canada)


    This report contains summaries of papers presented at the Workshop on Climate Change in the Western and Northern Forests of Canada, held on February 17-19, 2003, in Prince George BC. The workshop provided an opportunity for the exchange of views on the expected impacts of climate change on Canada's western and northern forests, and potential adaptive strategies. Several papers also dealt with the implications of climate change on environmental, social, and economic values of the forest, and institutional barriers to adaptation. Six key topics were addressed in informal 'knowledge cafe sessions': forest fires, insects and disease, forest productivity, forest practices, biodiversity, and non-timber forest values. Another informal series of meetings, dubbed 'open space sessions' centred around managing the various mechanisms, organizations, and stakeholders involved in climate change research and adaptation strategies. Lists containing the names of authors, and of workshop participants are also included.

  13. Small animal deworming protocols, client education, and veterinarian perception of zoonotic parasites in western Canada (United States)

    Stull, Jason W.; Carr, Anthony P.; Chomel, Bruno B.; Berghaus, Roy D.; Hird, David W.


    Questionnaires were mailed to veterinarians in western Canada to determine dog and cat deworming protocols and the association between perceived zoonotic risk and perceived prevalence of endoparasites and deworming protocols. Of the responding veterinarians (545), 13% and 39% recommended deworming protocols consistent with established guidelines for puppies and kittens, respectively. Mixed animal practitioners and high-perceived prevalence of Toxocara cati were associated with increased appropriate kitten deworming (P veterinarians noted an established hospital deworming protocol, although only 78% followed the protocol. Forty-four percent of veterinarians stated they discussed with all clients the zoonotic risk of animal-derived endoparasites, whereas the remainder discussed it only under particular circumstances or not at all. Most small animal deworming protocols recommended in western Canada begin too late to inhibit endoparasite shedding. Increased educational efforts directed at veterinarians are warranted. PMID:17436903

  14. Focal mechanisms and variations in tectonic stress fields in eastern Canada (western Quebec and southern Ontario) (United States)

    Asgharzadeh Sadegh, Parisa

    Earthquakes in western Quebec and southern Ontario present a major contribution to the natural hazards in south eastern Canada due to their proximity to major population centres. However, the seismic characteristics of the events in these regions have not been well documented. Improved knowledge of earthquake distribution and seismic controlling mechanisms provides a great benefit for earthquake hazard analysis in eastern Canada. The available information about the tectonic stress indicators, including focal mechanisms, was compiled for Canada prior to 1994. The present research is concentrated mainly on determination of the focal mechanisms and hypocentre locations of the earthquakes after 1993 with M > 3.5 to characterize the present-day regional and local stress fields in southern Ontario and western Quebec. An attempt was also made to differentiate local zones with comparatively homogeneous tectonic stresses orientation and seismic regimes, thus providing information for future re-assessment of the seismic hazard in each region. Considering seismic parameters such as the trend of the epicentres, focal depths and the state of stress of the events along with their tectonic settings, ten distinct clusters have been proposed for western Quebec and two clusters of events were determined for southern Ontario with comparatively consistent focal mechanisms. The locations and characteristics of seismicity clusters appear to be consistent with the hypothesis that they are near the locations of large historic and prehistoric events, and represent exceptionally persistent aftershocks of past large earthquakes.

  15. Sedimentary pigments in the western Barents Sea: A reflection of pelagic-benthic coupling? (United States)

    Morata, Nathalie; Renaud, Paul E.


    Local pelagic and sympagic primary production are usually the base of the Arctic food webs, and can be the main inputs of organic matter to the benthos. In order to characterize the major sources of production and understand the fate of organic matter to the benthos, water-column, ice, and sedimentary pigments of the Barents Sea were studied by HPLC analysis at 12 stations during the summer 2003, summer 2004, and spring 2005, in the framework of the CABANERA project. Chlorophyll a (chl a) concentration in surface sediments correlated significantly with total chl a integrated throughout the water-column as well as the chl a fluxes measured at 1 and 90 m water depth. This suggests that local water-column and ice-associated algae production are the main sources of fresh organic matter to the benthos. In the sediment, water-column, and ice, the major accessory pigment found was fucoxanthin, the marker pigment of diatoms, particularly dominant in spring. In summer, chlorophyll b, a marker of green algae, was found in stations influenced by Arctic waters, while 19'-hex-fucoxanthin, a marker of prymnesiophytes, was found in stations influenced by Atlantic water. The source of organic matter inputs to the benthos is thus highly dependent of the water masses influences in the summer. The ratio of sedimentary chl a to total phaeopigments (chl a/phaeo) was higher in the spring, and the total of phaeopigments in the sediment was correlated with water-column phaeopigments and with sedimentary phaeophorbide a, a pigment typical of grazing by zooplankton. This suggests that in the summer, organic matter reaching the sediment already has been degraded through grazing, while in spring, more fresh material reaches the sediment. The chl a/phaeo ratio was correlated with benthic oxygen demand measured by other researcher in this project, suggesting the importance of the quality of the organic matter reaching the sediment for benthos activities. Our results confirm a close pelagic

  16. Paleomagnetism of sedimentary strata and the origin of the structures in the western slope of South Urals (United States)

    Golovanova, I. V.; Danukalov, K. N.; Kadyrov, A. F.; Khidiyatov, M. M.; Sal'manova, R. Yu.; Shakurov, R. K.; Levashova, N. M.; Bazhenov, M. L.


    Paleomagnetic data may contribute to studying the formation history of orogens; in particular, these data can promote identifying the pattern and scales of deformations at the final stages of orogeny. We have conducted paleomagnetic studies of the Paleozoic and Neoproterozoic sediments in the western part of the Western Ural Megazone in South Urals. The detailed thermal demagnetization revealed the intermediate temperature magnetization component in most samples. This magnetization has a reversed polarity and has been acquired before folding or at the early stages of the deformations. The directions of this component are narrowly grouped in rocks of a different age in all the segments of the studied part of South Urals, and the regional average direction closely agrees with the reference paleomagnetic direction of 270 Ma for the East European Platform. The results of our study suggest the following conclusions: (1) the main magnetization component in the studied sedimentary rocks has a secondary origin; (2) this component has an age of 270 Ma and has been formed during the Kungur deformations (279-272 Ma ago) of the western part of South Urals; (3) neither a general rotation of the studied part of the Urals relative to the East European Platform nor local rotations of the individual tectonic blocks relative to each other are revealed; (4) the changes in the strike of the structures from NE within the Karatau uplift to the submeridional in the remaining part of the Urals is not an oroclinal bend.

  17. Quaternary volcanic-sedimentary sequences and evolution of the Llancanelo Lake region (Southern Mendoza, Western Argentina) evidenced from geoelectric methods (United States)

    de la Vega, Matias; Lopez, Ernesto; Osella, Ana; Rovere, Elizabeth I.; Violante, Roberto A.


    Llancanelo Lake region (Southern Mendoza Province, Western Argentina) is a key area for investigating the regional evolution of a tectonic basin affected by intense arc- and back-arc volcanism. However, the lack of enough outcrops makes it difficult to perform such reconstructions. In order to solve this problem, and with the aim of depicting the subsurface stratigraphy, 22 geoelectric surveys reaching more than 100 m depth were performed. The applied methodology, that combined geoelectrical measurements and field observations, is a continuation of previous works carried out in the region, and allowed for the first time to establish a near-surface stratigraphy that records the last evolutive stages of the lake. The studied region is mainly composed of Quaternary volcanic and sedimentary sequences. Four units were recognized on the basis of the geoelectrical differences (resistivity signal) supported by field observations where they crop out. Two of them have very high resistivity and are composed of basaltic lava flows, hence indicating the volcanic influence in the region. The other two have very low resistivity and correspond to sedimentary deposits, being the uppermost one composed of lacustrine sediments. The units were named according to the well-known stratigraphic scheme valid for the region. The studied stratigraphic sequence encompasses the time-span from the Pliocene to the present, and its interpretation allowed to establish the main evolutive stages, characterized by a complex interaction among tectonic, volcanic and climatic factors. The damming of the lake by basaltic flows and the consequent reduction of the lake's extension at times of intensive volcanic activity is one of the most significant events in its evolution.

  18. Projected deglaciation of western Canada in the twenty-first century (United States)

    Clarke, Garry K. C.; Jarosch, Alexander H.; Anslow, Faron S.; Radić, Valentina; Menounos, Brian


    Retreat of mountain glaciers is a significant contributor to sea-level rise and a potential threat to human populations through impacts on water availability and regional hydrology. Like most of Earth’s mountain glaciers, those in western North America are experiencing rapid mass loss. Projections of future large-scale mass change are based on surface mass balance models that are open to criticism, because they ignore or greatly simplify glacier physics. Here we use a high-resolution regional glaciation model, developed by coupling physics-based ice dynamics with a surface mass balance model, to project the fate of glaciers in western Canada. We use twenty-first-century climate scenarios from an ensemble of global climate models in our simulations; the results indicate that by 2100, the volume of glacier ice in western Canada will shrink by 70 +/- 10% relative to 2005. According to our simulations, few glaciers will remain in the Interior and Rockies regions, but maritime glaciers, in particular those in northwestern British Columbia, will survive in a diminished state. We project the maximum rate of ice volume loss, corresponding to peak input of deglacial meltwater to streams and rivers, to occur around 2020-2040. Potential implications include impacts on aquatic ecosystems, agriculture, forestry, alpine tourism and water quality.


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    Full Text Available The Rosso Ammonitico of the Montagna Grande area is very interesting because of the great diversification in facies and thickness in three very closely situated sections. The Jurassic succession in this area is that typical of the Trapanese Domain. It starts with a thick pile of platform limestones (Inici Formation: Hettangian - Sinemurian that are overlain by typically condensed and commonly nodular pelagic limestones (Rosso Ammonitico: Middle Jurassic - lowermost Cretaceous. The good exposure of this succession in active quarries allows observation of sedimentological and palaeontological details and to improve the understanding of the Jurassic tectono-sedimentary evolution. The Rocca chi Parra quarry shows a stepped surface, with a relief of some metres, incised in the Inici Formation. It is covered by lenticular or wedge-shaped lithosomes a few metres-thick of highly condensed Rosso Ammonitico. It is interpreted as a slide scar along which a thin but extensive block of lithified platform limestones was detached and slid downslope. The Poggio Roccione quarry shows neptunian sills and collapse structures in the middle part of the Rosso Ammonitico that on the whole is thicker (about 12 m than at Rocca chi Parra. They indicate sea-floor instability probably due to seismic shocks with brittle to plastic behaviour of sediments depending on their coherence. The Montagna Grande outcrop shows an even thicker succession which includes a wedge of cherty limestones about 10 m thick intercalated between a lower and an upper Rosso Ammonitico calcareous unit. The features described in these three sections document a highly irregular sea-floor topography which in turn was controlled by several phases of extensional tectonics during Mid and Late Jurassic pelagic sedimentation. Structurally higher sectors closer to fault scarps were affected by a very condensed sedimentation, the opening of subvertical dykes and the triggering of large slides. Structurally

  20. Volcano-sedimentary processes operating on a marginal continental arc: the Archean Raquette Lake Formation, Slave Province, Canada (United States)

    Mueller, W. U.; Corcoran, P. L.


    The 200-m thick, volcano-sedimentary Raquette Lake Formation, located in the south-central Archean Slave Province, represents a remnant arc segment floored by continental crust. The formation overlies the gneissic Sleepy Dragon Complex unconformably, is laterally interstratified with subaqueous mafic basalts of the Cameron River volcanic belt, and is considered the proximal equivalent of the turbidite-dominated Burwash Formation. A continuum of events associated with volcanism and sedimentation, and controlled by extensional tectonics, is advocated. A complex stratigraphy with three volcanic and three sedimentary lithofacies constitute the volcano-sedimentary succession. The volcanic lithofacies include: (1) a mafic volcanic lithofacies composed of subaqueous pillow-pillow breccia, and subaerial massive to blocky flows, (2) a felsic volcanic lithofacies representing felsic flows that were deposited in a subaerial environment, and (3) a felsic volcanic sandstone lithofacies interpreted as shallow-water, wave- and storm-reworked pyroclastic debris derived from explosive eruptions. The sedimentary lithofacies are represented by: (1) a conglomerate-sandstone lithofacies consistent with unconfined debris flow, hyperconcentrated flood flow and talus scree deposits, as well as minor high-energy stream flow conglomerates that formed coalescing, steep-sloped, coarse-clastic fan deltas, (2) a sandstone lithofacies, interpreted as hyperconcentrated flood flow deposits that accumulated at the subaerial-subaqueous interface, and (3) a mudstone lithofacies consistent with suspension sedimentation in a small restricted lagoon-type setting. The Raquette Lake Formation is interpreted as a fringing continental arc that displays both high-energy clastic sedimentation and contemporaneous effusive and explosive mafic and felsic volcanism. Modern analogues that develop along active plate margins in which continental crust plays a significant role include Japan and the Baja California

  1. Seismic velocities within the sedimentary succession of the Canada Basin and southern Alpha-Mendeleev Ridge, Arctic Ocean: evidence for accelerated porosity reduction? (United States)

    Shimeld, John; Li, Qingmou; Chian, Deping; Lebedeva-Ivanova, Nina; Jackson, Ruth; Mosher, David; Hutchinson, Deborah


    The Canada Basin and the southern Alpha-Mendeleev ridge complex underlie a significant proportion of the Arctic Ocean, but the geology of this undrilled and mostly ice-covered frontier is poorly known. New information is encoded in seismic wide-angle reflections and refractions recorded with expendable sonobuoys between 2007 and 2011. Velocity-depth samples within the sedimentary succession are extracted from published analyses for 142 of these records obtained at irregularly spaced stations across an area of 1.9E + 06 km2. The samples are modelled at regional, subregional and station-specific scales using an exponential function of inverse velocity versus depth with regionally representative parameters determined through numerical regression. With this approach, smooth, non-oscillatory velocity-depth profiles can be generated for any desired location in the study area, even where the measurement density is low. Practical application is demonstrated with a map of sedimentary thickness, derived from seismic reflection horizons interpreted in the time domain and depth converted using the velocity-depth profiles for each seismic trace. A thickness of 12-13 km is present beneath both the upper Mackenzie fan and the middle slope off of Alaska, but the sedimentary prism thins more gradually outboard of the latter region. Mapping of the observed-to-predicted velocities reveals coherent geospatial trends associated with five subregions: the Mackenzie fan; the continental slopes beyond the Mackenzie fan; the abyssal plain; the southwestern Canada Basin; and, the Alpha-Mendeleev magnetic domain. Comparison of the subregional velocity-depth models with published borehole data, and interpretation of the station-specific best-fitting model parameters, suggests that sandstone is not a predominant lithology in any of the five subregions. However, the bulk sand-to-shale ratio likely increases towards the Mackenzie fan, and the model for this subregion compares favourably with

  2. Seismic velocities within the sedimentary succession of the Canada Basin and southern Alpha-Mendeleev Ridge, Arctic Ocean: evidence for accelerated porosity reduction? (United States)

    Shimeld, John; Li, Qingmou; Chian, Deping; Lebedeva-Ivanova, Nina; Jackson, Ruth; Mosher, David; Hutchinson, Deborah R.


    The Canada Basin and the southern Alpha-Mendeleev ridge complex underlie a significant proportion of the Arctic Ocean, but the geology of this undrilled and mostly ice-covered frontier is poorly known. New information is encoded in seismic wide-angle reflections and refractions recorded with expendable sonobuoys between 2007 and 2011. Velocity–depth samples within the sedimentary succession are extracted from published analyses for 142 of these records obtained at irregularly spaced stations across an area of 1.9E + 06 km2. The samples are modelled at regional, subregional and station-specific scales using an exponential function of inverse velocity versus depth with regionally representative parameters determined through numerical regression. With this approach, smooth, non-oscillatory velocity–depth profiles can be generated for any desired location in the study area, even where the measurement density is low. Practical application is demonstrated with a map of sedimentary thickness, derived from seismic reflection horizons interpreted in the time domain and depth converted using the velocity–depth profiles for each seismic trace. A thickness of 12–13 km is present beneath both the upper Mackenzie fan and the middle slope off of Alaska, but the sedimentary prism thins more gradually outboard of the latter region. Mapping of the observed-to-predicted velocities reveals coherent geospatial trends associated with five subregions: the Mackenzie fan; the continental slopes beyond the Mackenzie fan; the abyssal plain; the southwestern Canada Basin; and, the Alpha-Mendeleev magnetic domain. Comparison of the subregional velocity–depth models with published borehole data, and interpretation of the station-specific best-fitting model parameters, suggests that sandstone is not a predominant lithology in any of the five subregions. However, the bulk sand-to-shale ratio likely increases towards the Mackenzie fan, and the model for this subregion compares

  3. The first deep heat flow determination in crystalline basement rocks beneath the Western Canadian Sedimentary Basin (United States)

    Majorowicz, Jacek; Chan, Judith; Crowell, James; Gosnold, Will; Heaman, Larry M.; Kück, Jochem; Nieuwenhuis, Greg; Schmitt, Douglas R.; Unsworth, Martyn; Walsh, Nathaniel; Weides, Simon


    Heat flow (Q) determined from bottom-hole temperatures measured in oil and gas wells in Alberta show a large scatter with values ranging from 40 to 90 mW m-2. Only two precise measurements of heat flow were previously reported in Alberta, and were made more than half a century ago. These were made in wells located near Edmonton, Alberta, and penetrated the upper kilometre of clastic sedimentary rocks yielding heat flows values of 61 and 67 mW m-2 (Garland & Lennox). Here, we report a new precise heat flow determination from a 2363-m deep well drilled into basement granite rocks just west of Fort McMurray, Alberta (the Hunt Well). Temperature logs acquired in 2010-2011 show a significant increase in the thermal gradient in the granite due to palaeoclimatic effects. In the case of the Hunt Well, heat flow at depths >2200 m is beyond the influence of the glacial-interglacial surface temperatures. Thermal conductivity and temperature measurements in the Hunt Well have shown that the heat flow below 2.2 km is 51 mW m-2 (±3 mW m-2), thermal conductivity measured by the divided bar method under bottom of the well in situ like condition is 2.5 W m-1 K-1, and 2.7 W m-1 K-1 in ambient conditions), and the geothermal gradient was measured as 20.4 mK m-1. The palaeoclimatic effect causes an underestimate of heat flow derived from measurements collected at depths shallower than 2200 m, meaning other heat flow estimates calculated from basin measurements have likely been underestimated. Heat production (A) was calculated from spectral gamma recorded in the Hunt Well granites to a depth of 1880 m and give an average A of 3.4 and 2.9 μW m-3 for the whole depth range of granites down to 2263 m, based on both gamma and spectral logs. This high A explains the relatively high heat flow measured within the Precambrian basement intersected by the Hunt Well; the Taltson Magmatic Zone. Heat flow and related heat generation from the Hunt Well fits the heat flow-heat generation

  4. Hydrothermal bitumen generated from sedimentary organic matter of rift lakes - Lake Chapala, Citala Rift, western Mexico

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    Zarate del Valle, Pedro F. [Departamento de Quimica, Universidad de Guadalajara - CUCEI, Ap. Postal 4-021, Guadalajara, Jalisco CP 44410 (Mexico); Simoneit, Bernd R.T. [Environmental and Petroleum Geochemistry Group, College of Oceanic and Atmospheric Sciences, Oregon State University, Building 104, Corvallis, OR 97331-5503 (United States)]. E-mail:


    Lake Chapala is in the Citala Rift of western Mexico, which in association with the Tepic-Zacoalco and Colima Rifts, form the well-known neotectonic Jalisco continental triple junction. The rifts are characterized by evidence for both paleo- and active hydrothermal activity. At the south shore of the lake, near the Los Gorgos sublacustrine hydrothermal field, there are two tar emanations that appear as small islands composed of solid, viscous and black bitumen. Aliquots of tar were analyzed by GC-MS and the mixtures are comprised of geologically mature biomarkers and an UCM. PAH and n-alkanes are not detectable. The biomarkers consist mainly of hopanes, gammacerane, tricyclic terpanes, carotane and its cracking products, steranes, and drimanes. The biomarker composition and bulk C isotope composition ({delta} {sup 13}C = -21.4%) indicate an organic matter source from bacteria and algae, typical of lacustrine ecosystems. The overall composition of these tars indicates that they are hydrothermal petroleum formed from lacustrine organic matter in the deeper sediments of Lake Chapala exceeding 40 ka ({sup 14}C) in age and then forced to the lakebed by tectonic activity. The absence of alkanes and the presence of an UCM with mature biomarkers are consistent with rapid hydrothermal oil generation and expulsion at temperatures of 200-250 deg. C. The occurrence of hydrothermal petroleum in continental rift systems is now well known and should be considered in future energy resource exploration in such regions.

  5. Past and Present Glacial Sedimentary Environments in Krossfjorden, Western Svalbard: Glacier Front Evolution (United States)

    Howe, J. A.; Husum, K.; Forwick, M.; Abernethy, C.; Macdonald, F.; Kohler, J.


    The Arctic will probably experience the most severe environmental change on Earth with an estimated annual average warming of 4 - 8°C degrees. The fjord systems of western Svalbard are highly sensitive to the present warming and are therefore very vulnerable to change. These `natural Arctic laboratories', are influenced by both temperate Atlantic water advected from the West Spitsbergen Current as well as atmospheric input from North America, Europe and Asia. Furthermore, marine terminating glaciers locally influence many Svalbard fjords. Thus, Svalbard is an important site for investigations of polar marine environmental and climate change. The distribution and movement of glacier fronts in the Krossfjorden-Kongsfjorden region has previously been mapped using surface vessels, yet the innermost part of these fjords and the glacier front environments have not been subject to detailed surveys. In this study, the seafloor from the inner part of a fjord in Krossfjorden, the Fjortendejulibuka, and the adjacent to the tide water Fjortendejulibreen glacial front, has been mapped using an autonomous underwater vehicle (AUV) equipped with a swath sonar system, providing very high-resolution bathymetry, side-scan data and the seabed photography to document the seabed geomorphology, sediment type and benthic habitat. Preliminary bathymetric, photographic and side-scan data suggests sedimentation from subglacial meltwater dominates the ice-proximal zone whilst settling from suspension is more prevalent away from the glacier. Seabed photographs from the AUV reveal a fine-grained depositional environment with fine-grain sediments and intense bioturbation with a limited benthic species diversity. Glaciomarine systems are characterized by a dynamic climatically controlled environment and the use of autonomous and robotic vehicles can greatly aid in the monitoring of change by collecting high-resolution datasets where vessel based observations are lacking.

  6. Site-specific estimates of water yield applied in regional acid sensitivity surveys across western Canada

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    Patrick D. SHAW


    Full Text Available Runoff or water yield is an important input to the Steady-State Water Chemistry (SSWC model for estimating critical loads of acidity. Herein, we present site-specific water yield estimates for a large number of lakes (779 across three provinces of western Canada (Manitoba, Saskatchewan, and British Columbia using an isotope mass balance (IMB approach. We explore the impact of applying site-specific hydrology as compared to use of regional runoff estimates derived from gridded datasets in assessing critical loads of acidity to these lakes. In general, the average water yield derived from IMB is similar to the long-term average runoff; however, IMB results suggest a much larger range in hydrological settings of the lakes, attributed to spatial heterogeneity in watershed characteristics and landcover. The comparison of critical loads estimates from the two methods suggests that use of average regional runoff data in the SSWC model may overestimate critical loads for the majority of lakes due to systematic skewness in the actual runoff distributions. Implications for use of site-specific hydrology in regional critical loads assessments across western Canada are discussed.

  7. Antibody responses to Borrelia burgdorferi detected by western blot vary geographically in Canada. (United States)

    Ogden, Nicholas H; Arsenault, Julie; Hatchette, Todd F; Mechai, Samir; Lindsay, L Robbin


    Lyme disease is emerging in eastern and central Canada, and most cases are diagnosed using the two-tier serological test (Enzyme Immuno Assay [EIA] followed by Western blot [WB]). Simplification of this algorithm would be advantageous unless it impacts test performance. In this study, accuracy of individual proteins of the IgG WB algorithm in predicting the overall test result in samples from Canadians was assessed. Because Borrelia burgdorferi strains vary geographically in Canada, geographic variations in serological responses were also explored. Metrics of relative sensitivity, specificity and the kappa statistic measure of concordance were used to assess the capacity of responses to individual proteins to predict the overall IgG WB result of 2524 EIA (C6)-positive samples from across Canada. Geographic and interannual variations in proportions of samples testing positive were explored by logistic regression. No one protein was highly concordant with the IgG WB result. Significant variations were found amongst years and geographic regions in the prevalence of samples testing positive using the overall IgG WB algorithm, and for individual proteins of the algorithm. In most cases the prevalence of samples testing positive were highest in Nova Scotia, and lower in samples from Manitoba westwards. These findings suggest that the current two tier test may not be simplified and continued use of the current two-tier test method and interpretation is recommended. Geographic and interannual variations in the prevalence of samples testing positive may be consistent with B. burgdorferi strain variation in Canada, and further studies are needed to explore this.

  8. The Rocky Mountain population of the western Canada goose: its distribution, habitats, and management (United States)

    Krohn, William B.; Bizeau, Elwood G.


    The western Canada goose (Branta canadensis moffitti) was divided into a Rocky Mountain population (RMP) and a Pacific population (PP) on the basis of band recovery patterns examined in this study and recovery data from other investigators. Habitat information obtained from nine cooperating wildlife agencies within the RMP's range provided a base line for evaluating future changes in nesting, molting, and wintering areas. The habitat inventory indicated that none of the seasonal habitats were currently limiting the size of the RMP. The RMP's range is divided into 15 reference areas and these are briefly described. Past studies of Canada geese in the Intermountain Region are reviewed. Topics covered in the discussion of breeding biology are nesting chronology, spring population composition, breeding age, clutch size, nesting success. artificial nesting structures, and gosling survival. Much of the mortality of Canada geese occurs before the birds are fledged. Man-made nesting structures reduce losses during incubation. but research is needed on the relations between brooding sites and gosling survival. Some western Canada geese, mainly prebreeders and unsuccessful nesters, make molt migrations to and from molting areas during and after the brood-rearing season. More than half of these molt-migrants are yearlings too young to nest; there are indications that even some successful nesters leave nesting areas to molt before the fledging of their offspring. Geese 2 years old or older may serve as guides to traditional molting areas for the first-time migrants (i.e., yearlings). Lack of disturbance appears to influence selection of specific molting areas within the nesting range of moffitti, whereas movements of molters out of the Intermountain Region may be related to the evolution of this subspecies. Apparently. molters of both the PP and RMP that leave the Region go to the Northwest Territories of Canada. Although the taxonomic status of moffitti as related to the

  9. Persistent millennial-scale shifts in moisture regimes in western Canada during the past six millennia (United States)

    Cumming, Brian F.; Laird, Kathleen R.; Bennett, Joseph R.; Smol, John P.; Salomon, Anne K.


    Inferences of past climatic conditions from a sedimentary record from Big Lake, British Columbia, Canada, over the past 5,500 years show strong millennial-scale patterns, which oscillate between periods of wet and drier climatic conditions. Higher frequency decadal- to centennial-scale fluctuations also occur within the dominant millennial-scale patterns. These changes in climatic conditions are based on estimates of changes in lake depth and salinity inferred from diatom assemblages in a well dated sediment core. After periods of relative stability, abrupt shifts in diatom assemblages and inferred climatic conditions occur approximately every 1,220 years. The correspondence of these shifts to millennial-scale variations in records of glacial expansion/recession and ice-rafting events in the Atlantic suggest that abrupt millennial-scale shifts are important to understanding climatic variability in North America during the mid- to late Holocene. Unfortunately, the spatial patterns and mechanisms behind these large and abrupt swings are poorly understood. Similar abrupt and prolonged changes in climatic conditions today could pose major societal challenges for many regions. PMID:12461174

  10. Cretaceous—Quaternary tectonic evolution of the Tatra Mts (Western Carpathians: constraints from structural, sedimentary, geomorphological, and fission track data

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    Králiková Silvia


    Full Text Available The Tatra Mts area, located in the northernmost part of Central Western Carpathians on the border between Slovakia and Poland, underwent a complex Alpine tectonic evolution. This study integrates structural, sedimentary, and geomorphological data combined with fission track data from the Variscan granite rocks to discuss the Cretaceous to Quaternary tectonic and landscape evolution of the Tatra Mts. The presented data can be correlated with five principal tectonic stages (TS, including neotectonics. TS-1 (~95-80 Ma is related to mid-Cretaceous nappe stacking when the Tatric Unit was overlain by Mesozoic sequences of the Fatric and Hronic Nappes. After nappe stacking the Tatric crystalline basement was exhumed (and cooled in response to the Late Cretaceous/Paleogene orogenic collapse followed by orogen-parallel extension. This is supported by 70 to 60 Ma old zircon fission track ages. Extensional tectonics were replaced by transpression to transtension during the Late Paleocene to Eocene (TS-2; ~80-45 Ma. TS-3 (~45-20 Ma is documented by thick Oligocene-lowermost Miocene sediments of the Central Carpathian Paleogene Basin which kept the underlying Tatric crystalline basement at elevated temperatures (ca. > 120 °C and < 200 °C. The TS-4 (~20-7 Ma is linked to slow Miocene exhumation rate of the Tatric crystalline basement, as it is indicated by apatite fission track data of 9-12 Ma. The final shaping of the Tatra Mts has been linked to accelerated tectonic activity since the Pliocene (TS-5; ~7-0 Ma.

  11. Fugitive Emissions from Conventional and Hydraulically Fractured Natural Gas Developments in Western Canada (United States)

    Atherton, E. E.; Risk, D. A.; Lavoie, M.; Marshall, A. D.; Baillie, J.; Williams, J. P.


    Presently, fugitive emissions released into the atmosphere during the completion and production of oil and gas wells are poorly regulated within Canada. Some possible upstream sources of these emissions include flowback during well completions, liquid unloading, chemical injection pumps, and equipment leaks. The environmental benefits of combusting natural gas compared to oil or coal are negated if methane leakages surpass 3.2% of total production, so it is important to have a thorough understanding of these fugitive emissions. This study compares atmospheric leakage pathways of methane and other fugitive gases in both conventional and unconventional oil and gas developments in Western Canada to help fill this knowledge gap. Over 5000 kilometers of mobile survey campaigns were completed in carefully selected developments in the Montney shale play in British Columbia, and in conventional oil fields in Alberta. These sites are developed by more than 25 different operators. High precision laser and UV fluorescence gas analyzers were used to gather geolocated trace gas concentrations at a frequency of 1 Hz while driving. These data were processed with an adaptive technique to compensate for fluctuations in background concentrations for each gas. The residual excess concentrations were compositionally fingerprinted on the basis of the expected gas ratios for potential emission sites in order to definitively attribute anomalies to infrastructural leak sources. Preliminary results from the mobile surveys of both conventional and unconventional oil and gas sites are presented here. Pathways of methane and other fugitive gases are mapped to their respective sources, identifying common causes of emissions leaks across the oil and gas industry. This is the first bottom-up study of fugitive emissions from Canadian energy developments to produce publicly available data. These findings are significant to operators interested in lowering emissions for economic benefit, as well as

  12. A retrospective study of canine strychnine poisonings from 1998 to 2013 in Western Canada. (United States)

    Cowan, Vanessa E; Blakley, Barry R


    This study describes observations related to 93 cases of strychnine poisoning in dogs over a 16-year period in Saskatchewan, Alberta, and Manitoba. Epidemiological information describing age, gender, breed, and size of the dogs, geographical distribution of poisonings, and strychnine concentrations in tissue matrices were tabulated. The mortality in dogs poisoned with strychnine was 60.2%. Strychnine poisoning cases varied by year (P = 0.0012) and by season (P = 0.0005). The highest number of confirmed cases occurred in years 2000 and 2001. Poisonings occurred most frequently during the spring. There were no statistical differences related to age or gender, but older, male dogs appeared to be more commonly affected. Large dog breeds were most commonly affected. Strychnine was detected in multiple tissue matrices, including stomach contents, liver, urine, vomitus, and gastric washings. The study indicates that strychnine poisoning in the dog remains a common toxicosis in western Canada.

  13. Letting go: How newly graduated registered nurses in Western Canada decide to exit the nursing profession. (United States)

    Chachula, Kathryn M; Myrick, Florence; Yonge, Olive


    The Canadian Nurses Association (CNA) estimates a nursing shortage in Canada will rise to 60,000 registered nurses by 2022. Further compounding this crisis is the approximate 14-61% of new nursing graduates who will change nursing roles or exit the profession. To explore the factors and basic psychosocial process involved in the decisions of newly graduated registered nurses in Western Canada who permanently exit the nursing profession within five years. Data was collected through unstructured and semi-structured interviews using the Glaserian grounded theory method. Participants were found to be in a process of letting go of nursing that commenced as students and continued as they entered practice as registered nurses. Four major themes were identified. 1) Navigating constraints of the healthcare system and workplace: participants encountered difficulties adjusting to shiftwork and workload. 2) Negotiating social relationships, hierarchies, and troublesome behaviors; specifically hierarchal and horizontal violence. 3) Facing fears, traumas and challenges. 4) Weighing competing rewards and tensions which resulted in leaving the nursing profession. Students and subsequently new nursing graduates require a variety of supports to establish a nursing identity and remain in the profession. These supports include a manageable workload; meaningful orientation; interprofessional teamwork; and engagement within transformational and authentic leadership constructs. New nurses require a sense of being welcomed, valued, respected and accepted into the workplace environment, as well as constructive feedback, emotional support and debriefing to face workplace challenges. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. EarthScope Transportable Array Siting Outreach Activities in Alaska and Western Canada (United States)

    Gardine, L.; Dorr, P. M.; Tape, C.; McQuillan, P.; Taber, J.; West, M. E.; Busby, R. W.


    The EarthScopeTransportable Array is working to locate over 260 stations in Alaska and western Canada. In this region, new tactics and partnerships are needed to increase outreach exposure. IRIS and EarthScope are partnering with the Alaska Earthquake Center, part of University of Alaska Geophysical Institute, to spread awareness of Alaska earthquakes and the benefits of the Transportable Array for Alaskans. Nearly all parts of Alaska are tectonically active. The tectonic and seismic variability of Alaska requires focused attention at the regional level, and the remoteness and inaccessibility of most Alaska villages and towns often makes frequent visits difficult. For this reason, Alaska outreach most often occurs at community events. When a community is accessible, every opportunity to engage the residents is made. Booths at state fairs and large cultural gatherings, such as the annual convention of the Alaska Federation of Natives, are excellent venues to distribute earthquake information and to demonstrate a wide variety of educational products and web-based applications related to seismology and the Transportable Array that residents can use in their own communities. Region-specific publications have been developed to tie in a sense of place for residents of Alaska. The Alaska content for IRIS's Active Earth Monitor will emphasize the widespread tectonic and seismic features and offer not just Alaska residents, but anyone interested in Alaska, a glimpse into what is going on beneath their feet. The concerted efforts of the outreach team will have lasting effects on Alaskan understanding of the seismic hazard and tectonics of the region. Efforts to publicize the presence of the Transportable Array in Alaska, western Canada, and the Lower 48 also continue. There have been recent articles published in university, local and regional newspapers; stories appearing in national and international print and broadcast media; and documentaries produced by some of the world

  15. Mercury risk to avian piscivores across western United States and Canada (United States)

    Jackson, Allyson K.; Evers, David C.; Eagles-Smith, Collin A.; Ackerman, Josh; Willacker, James J.; Elliott, John E.; Lepak, Jesse M; Vander Pol, Stacy S.; Bryan, Colleen E.


    The widespread distribution of mercury (Hg) threatens wildlife health, particularly piscivorous birds. Western North America is a diverse region that provides critical habitat to many piscivorous bird species, and also has a well-documented history of mercury contamination from legacy mining and atmospheric deposition. The diversity of landscapes in the west limits the distribution of avian piscivore species, complicating broad comparisons across the region. Mercury risk to avian piscivores was evaluated across the western United States and Canada using a suite of avian piscivore species representing a variety of foraging strategies that together occur broadly across the region. Prey fish Hg concentrations were size-adjusted to the preferred size class of the diet for each avian piscivore (Bald Eagle = 36 cm, Osprey = 30 cm, Common and Yellow-billed Loon = 15 cm, Western and Clark's Grebe = 6 cm, and Belted Kingfisher = 5 cm) across each species breeding range. Using a combination of field and lab-based studies on Hg effect in a variety of species, wet weight blood estimates were grouped into five relative risk categories including: background ( 3 μg/g). These risk categories were used to estimate potential mercury risk to avian piscivores across the west at a 1 degree-by-1 degree grid cell resolution. Avian piscivores foraging on larger-sized fish generally were at a higher relative risk to Hg. Habitats with a relatively high risk included wetland complexes (e.g., prairie pothole in Saskatchewan), river deltas (e.g., San Francisco Bay, Puget Sound, Columbia River), and arid lands (Great Basin and central Arizona). These results indicate that more intensive avian piscivore sampling is needed across Western North America to generate a more robust assessment of exposure risk.

  16. The Effect of Climate Change on Wetlands and Waterfowl in Western Canada: Incorporating Cropping Decisions into a Bioeconomic Model

    NARCIS (Netherlands)

    Withey, P.; Kooten, van G.C.


    We extend an earlier bioeconomic model of optimal duck harvest and wetland retention in the Prairie Pothole Region of Western Canada to include cropping decisions. Instead of a single state equation, the model has two state equations representing the population dynamics of ducks and the amount of

  17. Vertical resolution enhancement of the Phasor induction: Applications in western Canada

    Energy Technology Data Exchange (ETDEWEB)

    Rixon, M.D.; Kasperski, B.W.; Morriss, C.E

    A substantial number of wells in western Canada are drilled into thinly bedded reservoirs. Qualitative evaluation of these reservoirs is difficult using standard induction due to the poor vertical resolution and shoulder bed effect. The Phasor induction tool and Phasor processing reduce the shoulder bed effect but do not address the thin bed response. The recent introduction of enhanced resolution phasor (ERP) processing has made it possible, under favorable conditions, to fully resolve the resistivity of a 1 m bed. This results in accurate water saturation calculations and reserve estimates for thinly bedded formations, typically yielding a higher resistivity, resulting in lower water saturation and a higher reserve estimate. ERP processing also gives a better indication of the diameter of invasion in thin beds. However, to effectively utilize the processing, consideration must be given to its limitations, and severe borehole washouts or rugosity and large variations in invasion across a thick zone can adversely affect the processing. Sample logs are presented for five types of western Canadian reservoirs: Mississippian carbonate (dolomite, calcite); basal quartz formation (sand, shale, calcite); Viking formation (sand, shale, calcite, cement); Gilwood formation (sand, shale, calcite); and Halfway formation (sand, dolomite, anhydrite, calcite). 9 refs., 16 figs.

  18. Bias corrections of precipitation measurements across experimental sites in different ecoclimatic regions of western Canada (United States)

    Pan, Xicai; Yang, Daqing; Li, Yanping; Barr, Alan; Helgason, Warren; Hayashi, Masaki; Marsh, Philip; Pomeroy, John; Janowicz, Richard J.


    This study assesses a filtering procedure on accumulating precipitation gauge measurements and quantifies the effects of bias corrections for wind-induced undercatch across four ecoclimatic regions in western Canada, including the permafrost regions of the subarctic, the Western Cordillera, the boreal forest, and the prairies. The bias corrections increased monthly precipitation by up to 163 % at windy sites with short vegetation and sometimes modified the seasonal precipitation regime, whereas the increases were less than 13 % at sites shielded by forest. On a yearly basis, the increase of total precipitation ranged from 8 to 20 mm (3-4 %) at sites shielded by vegetation and 60 to 384 mm (about 15-34 %) at open sites. In addition, the bias corrections altered the seasonal precipitation patterns at some windy sites with high snow percentage ( > 50 %). This study highlights the need for and importance of precipitation bias corrections at both research sites and operational networks for water balance assessment and the validation of global/regional climate-hydrology models.

  19. Recent climatic, cryospheric, and hydrological changes over the interior of western Canada: a review and synthesis (United States)

    DeBeer, Chris M.; Wheater, Howard S.; Carey, Sean K.; Chun, Kwok P.


    It is well established that the Earth's climate system has warmed significantly over the past several decades, and in association there have been widespread changes in various other Earth system components. This has been especially prevalent in the cold regions of the northern mid- to high latitudes. Examples of these changes can be found within the western and northern interior of Canada, a region that exemplifies the scientific and societal issues faced in many other similar parts of the world, and where impacts have global-scale consequences. This region has been the geographic focus of a large amount of previous research on changing climatic, cryospheric, and hydrological regimes in recent decades, while current initiatives such as the Changing Cold Regions Network (CCRN) introduced in this review seek to further develop the understanding and diagnosis of this change and hence improve the capacity to predict future change. This paper provides a comprehensive review of the observed changes in various Earth system components and a concise and up-to-date regional picture of some of the temporal trends over the interior of western Canada since the mid- or late 20th century. The focus is on air temperature, precipitation, seasonal snow cover, mountain glaciers, permafrost, freshwater ice cover, and river discharge. Important long-term observational networks and data sets are described, and qualitative linkages among the changing components are highlighted. Increases in air temperature are the most notable changes within the domain, rising on average 2 °C throughout the western interior since 1950. This increase in air temperature is associated with hydrologically important changes to precipitation regimes and unambiguous declines in snow cover depth, persistence, and spatial extent. Consequences of warming air temperatures have caused mountain glaciers to recede at all latitudes, permafrost to thaw at its southern limit, and active layers over permafrost to thicken

  20. Sea-floor morphology and sedimentary environments in western Block Island Sound, offshore of Fishers Island, New York (United States)

    McMullen, Katherine Y.; Poppe, Lawrence J.; Danforth, William W.; Blackwood, Dann S.; Winner, William G.; Parker, Castle E.


    Multibeam-bathymetric and sidescan-sonar data, collected by the National Oceanic and Atmospheric Administration in a 114-square-kilometer area of Block Island Sound, southeast of Fishers Island, New York, are combined with sediment samples and bottom photography collected by the U.S. Geological Survey from 36 stations in this area in order to interpret sea-floor features and sedimentary environments. These interpretations and datasets provide base maps for studies on benthic ecology and resource management. The geologic features and sedimentary environments on the sea floor are products of the area’s glacial history and modern processes. These features include bedrock, drumlins, boulders, cobbles, large current-scoured bathymetric depressions, obstacle marks, and glaciolacustrine sediments found in high-energy sedimentary environments of erosion or nondeposition; and sand waves and megaripples in sedimentary environments characterized by coarse-grained bedload transport. Trawl marks are preserved in lower energy environments of sorting and reworking. This report releases the multibeam-bathymetric, sidescan-sonar, sediment, and photographic data and interpretations of the features and sedimentary environments in Block Island Sound, offshore Fishers Island.

  1. Sedimentary Records of Hyperpycnal Flows and the Influence of River Damming on Sediment Dynamics of Estuaries: Examples from the Nelson, Churchill, Moisie and Sainte-Marguerite Rivers (Canada) (United States)

    St-Onge, G.; Duboc, Q.; Boyer-Villemaire, U.; Lajeunesse, P.; Bernatchez, P.


    Sediment cores were sampled in the estuary of the Nelson and Churchill Rivers in western Hudson Bay, as well as in the estuary of the Moisie and Sainte-Marguerite Rivers in Gulf of St. Lawrence in order to evaluate the impact of hydroelectric dams on the sedimentary regime of these estuaries. The gravity cores at the mouth of the Nelson River recorded several cm-thick rapidly deposited layers with a reverse to normal grading sequence, indicating the occurrence of hyperpycnal flows generated by major floods during the last few centuries. These hyperpycnal flows were probably caused by ice-jam formation, which can increase both the flow and the sediment concentration following the breaching of such natural dams. Following the construction of hydroelectric dams since the 1960s, the regulation of river discharge prevented the formation of hyperpycnal flows, and hence the deposition of hyperpycnites in the upper part of the cores. In the core sampled in the estuary of the Churchill River, only one hyperpycnite was recorded. This lower frequency may be due to the enclosed estuary of the Churchill River, its weaker discharge and the more distal location of the coring site.In the Gulf of St. Lawrence, grain size measurements allowed the identification of a major flood around AD 1844±4 years in box cores from both the Sainte-Marguerite and Moisie Rivers, whereas a drastic decrease in variations in the median grain size occurred around AD ~1900 in the estuary of the Sainte-Marguerite River, highlighting the offshore impact of the SM1 dam construction in the early 1900s. Furthermore, sedimentological variations in the box cores from both estuaries have been investigated by wavelet analysis and the sharp disappearance of high frequencies around AD 1900 in the estuary of the dammed river (Sainte-Marguerite River), but not in the estuary of the natural river (Moisie River), also provides evidence of the influence of dams on the sedimentary regime of estuaries.

  2. Coal facies studies in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Kalkreuth, Wolfgang D. [Laboratorio de Carvao e de Petrologia Organica, Instituto de Geociencias, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Goncalves, 9500, 91501-970 Porto Alegre, RS (Brazil)


    The present study is a compilation of published data on coal facies studies in Canada based on coal petrological and other methods. The geological age of the coals range from the Devonian coal deposits in Arctic Canada to coals of Tertiary age in the Western Canada Sedimentary Basin, intermontane British Columbia and Arctic Canada. In terms of rank, the coal deposits studied range from lignite to low volatile bituminous. Coal petrological methods include maceral and microlithotype analyses, frequently integrated with data from palynological and geochemical analyses. Most recently, a number of studies have applied sequence stratigraphic concepts to the coal-bearing strata including the interpretation of coal petrological data in the context of this concept.

  3. Persistent and pervasive compositional shifts of western boreal forest plots in Canada. (United States)

    Searle, Eric B; Chen, Han Y H


    Species compositional shifts have important consequences to biodiversity and ecosystem function and services to humanity. In boreal forests, compositional shifts from late-successional conifers to early-successional conifers and deciduous broadleaves have been postulated based on increased fire frequency associated with climate change truncating stand age-dependent succession. However, little is known about how climate change has affected forest composition in the background between successive catastrophic fires in boreal forests. Using 1797 permanent sample plots from western boreal forests of Canada measured from 1958 to 2013, we show that after accounting for stand age-dependent succession, the relative abundances of early-successional deciduous broadleaves and early-successional conifers have increased at the expense of late-successional conifers with climate change. These background compositional shifts are persistent temporally, consistent across all forest stand ages and pervasive spatially across the region. Rising atmospheric CO2 promoted early-successional conifers and deciduous broadleaves, and warming increased early-successional conifers at the expense of late-successional conifers, but compositional shifts were not associated with climate moisture index. Our results emphasize the importance of climate change on background compositional shifts in the boreal forest and suggest further compositional shifts as rising CO2 and warming will continue in the 21st century. © 2016 John Wiley & Sons Ltd.

  4. Measurements of Ice Nuclei at a Remote Coastal Site in Western Canada (United States)

    Si, M.; Mason, R.; Li, J.; Dickie, R.; Chou, C.; Ladino Moreno, L.; Yakobi-Hancock, J.; Schiller, C. L.; Jones, K.; Leaitch, W. R.; Desiree, T. S.; Abbatt, J.; Huffman, J. A.; Bertram, A. K.


    Aerosol particles are abundant in the atmosphere, and they can influence climate by modifying the formation of ice clouds and mixed-phase clouds. Understanding the sources of ice nuclei (IN) should lead to better predictions of climate. Many current instruments for measuring atmospheric concentrations of IN are not capable of providing size-resolved information. Such knowledge is useful in identifying the sources of IN. The recently developed micro-orifice uniform deposit impactor-droplet freezing technique (MOUDI-DFT) provides size-resolved information by combining an established immersion freezing apparatus with a cascade impactor for sample collection. Here we show results from a field study undertaken at a remote coastal site in Western Canada in August, 2013 using this technique. The size distributions of IN will be presented. A recent study suggested that the IN population in remote marine regions might be dominated by primary biogenic particles. To address the sources of IN from this campaign, correlations between IN concentrations and biological aerosols, carbonaceous aerosols, and other possible IN sources will be discussed.

  5. Exceptionally preserved crustaceans from western Canada reveal a cryptic Cambrian radiation (United States)

    Harvey, Thomas H. P.; Vélez, Maria I.; Butterfield, Nicholas J.


    The early history of crustaceans is obscured by strong biases in fossil preservation, but a previously overlooked taphonomic mode yields important complementary insights. Here we describe diverse crustacean appendages of Middle and Late Cambrian age from shallow-marine mudstones of the Deadwood Formation in western Canada. The fossils occur as flattened and fragmentary carbonaceous cuticles but provide a suite of phylogenetic and ecological data by virtue of their detailed preservation. In addition to an unprecedented range of complex, largely articulated filtering limbs, we identify at least four distinct types of mandible. Together, these fossils provide the earliest evidence for crown-group branchiopods and total-group copepods and ostracods, extending the respective ranges of these clades back from the Devonian, Pennsylvanian, and Ordovician. Detailed similarities with living forms demonstrate the early origins and subsequent conservation of various complex food-handling adaptations, including a directional mandibular asymmetry that has persisted through half a billion years of evolution. At the same time, the Deadwood fossils indicate profound secular changes in crustacean ecology in terms of body size and environmental distribution. The earliest radiation of crustaceans is largely cryptic in the fossil record, but "small carbonaceous fossils" reveal organisms of surprisingly modern aspect operating in an unfamiliar biosphere.

  6. A novel Rickettsia species detected in Vole Ticks (Ixodes angustus) from Western Canada. (United States)

    Anstead, Clare A; Chilton, Neil B


    The genomic DNA of ixodid ticks from western Canada was tested by PCR for the presence of Rickettsia. No rickettsiae were detected in Ixodes sculptus, whereas 18% of the I. angustus and 42% of the Dermacentor andersoni organisms examined were PCR positive for Rickettsia. The rickettsiae from each tick species were characterized genetically using multiple genes. Rickettsiae within the D. andersoni organisms had sequences at four genes that matched those of R. peacockii. In contrast, the Rickettsia present within the larvae, nymphs, and adults of I. angustus had novel DNA sequences at four of the genes characterized compared to the sequences available from GenBank for all recognized species of Rickettsia and all other putative species within the genus. Phylogenetic analyses of the sequence data revealed that the rickettsiae in I. angustus do not belong to the spotted fever, transitional, or typhus groups of rickettsiae but are most closely related to "Candidatus Rickettsia kingi" and belong to a clade that also includes R. canadensis, "Candidatus Rickettsia tarasevichiae," and "Candidatus Rickettsia monteiroi."

  7. Self-directed learning of hospital pharmacy residents in western Canada. (United States)

    Levchuk, J W


    The extent of self-directed learning among hospital pharmacy residents in western Canada was studied. A preresidency questionnaire and a postresidency group interview with a set of questionnaires were used. The residents were asked to list learning projects conducted in their residency programs; these learning projects were categorized as self-directed, mutual-agreement, and preceptor-directed. A postinterview questionnaire was used to obtain postresidency measurements of self-directedness and resident autonomy. Twenty-four residents provided data on 164 learning projects. Projects with the most meaningfulness, high achievement contribution, positive motivation, and relevance corresponded with the self-directed approach. Residents who had more meaningful learning entered their residencies with no more self-directedness than other residents, but they did have more autonomy in their residencies. No particular type of project, with respect to learner autonomy, was found to be more problematic than the others. Facilitation of learner autonomy in a hospital pharmacy residency may increase the value of self-directed learning projects in general and improve the resident's self-directedness. Self-directed learning should continue to be part of residency programs.

  8. Screening for neurocognitive impairment, depression, and anxiety in HIV-infected patients in Western Europe and Canada



    CRANIum, a cross-sectional epidemiology study in Western Europe and Canada, was conducted to describe and compare the prevalence of a positive screen for neurocognitive impairment (NCI), depressive symptoms, and anxiety in an HIV-positive population either receiving combination antiretroviral therapy (cART) or who were naive to antiretroviral therapy (ART). HIV-positive patients ≥18 years of age attending a routine medical follow-up visit and able to complete the designated screening tools we...

  9. Pliocene-Quaternary contourite depositional system along the south-western Adriatic margin: changes in sedimentary stacking pattern and associated bottom currents (United States)

    Pellegrini, Claudio; Maselli, Vittorio; Trincardi, Fabio


    The Pliocene-Quaternary history of the south-western Adriatic margin, represented by a complex contourite depositional system, records the palaeoceanography of the basin and the interactions between oceanographic processes and the uneven slope morphology that resulted from tectonic deformation. Three main stages can be recognized: (1) during the Pliocene, a giant sediment drift formed on the southern flank of the slope-transverse Gondola anticline that focused and accelerated the flow of slope-parallel bottom currents; (2) since the early to middle Pleistocene transition, a reorganization of bottom-current pathways led to a sharp change in the sedimentary architecture of the margin that became dominated by the growth of contourite deposits; (3) as of 350 ka, landward-migrating contourites on the outer shelf (less than 120 m water depth) reflect the presence of bottom currents also in shallow waters. This analysis of the sedimentary stacking pattern of the contourite depositional system that developed along the south-western Adriatic margin since the Pliocene enables disentangling the processes that controlled changes in bottom-current activity, demonstrating that bottom-current deposits constitute the bulk of depositional sequences at the Milankovitch timescale.

  10. Drainage evolution of the Heihe River in western Hexi Corridor, China, derived from sedimentary and magnetostratigraphic results (United States)

    Pan, Baotian; Chen, Dianbao; Hu, Xiaofei; Cao, Xilin; Chen, Jinjun; Mao, Junwei


    The uplifting of the Tibetan Plateau has significantly changed the environment in surrounding areas by delivering abundant water and sediment. The Heihe River draining the Qilian Shan in the NE Tibetan Plateau acts as a dominant sediment routing system from the uplifted NE Tibetan Plateau to the Hexi Corridor as well as the Badain Jaran Desert. Reconstructing the evolution of the Heihe River could provide evidence for the birth of the Badain Jaran Desert and enhance the understanding of sedimentary basin fill and the relationship between tectonism, drainage evolution and environmental changes. With this aim, two parallel cores (DWJ and XKJD with depths of 140 and 68.2 m, respectively) were drilled in the floodplain of the Heihe River. The facies analysis of the sedimentary sequences from the drilling cores showed that the sedimentary environment changed from the lake system to a delta system and finally to a fluvial system at the depths of ∼133.3 and ∼68 m, respectively. The magnetostratigraphic results revealed ages of approximately 1.75 and 1.12 Ma for the DWJ and XKJD cores, respectively, and an age of approximately 1.1 Ma for the transition from delta to fluvial environment in both the cores. The change of the sedimentary environment at approximately 1.1 Ma was caused by the formation of the integrated Heihe River. The integrated Heihe River may have developed via mechanisms such as river capture and river diversion due to the uplifting of the North Qilian Shan and the Longshou Shan. The present study suggested that the formation of large inland rivers, such as the Heihe River and the Shiyang River in NW China, played an important role in the evolution of the deserts and the Loess Plateau.

  11. Longitudinal assessment of PCBs and chlorinated pesticides in pregnant women from Western Canada

    Directory of Open Access Journals (Sweden)

    Hauser Russ


    Full Text Available Abstract Background Maternal exposures to organochlorines prior to pregnancy are considered a risk to neonatal welfare, specifically in relation to neurocognitive functions. There is growing interest in the evaluation of maternal blood testing as a marker for fetal exposure as well as the variable geographic distribution of these priority chemicals. Methods Three hundred and twenty-three women in the second trimester of pregnancy entered the study at a prenatal clinic providing genetic counselling information. Subjects who had an indication for genetic amniocentesis based on late maternal age were eligible to participate. Two hundred and thirty-eight completed an environmental questionnaire. A sample of amniotic fluid was taken for karyotype analysis in 323 women and blood samples during pregnancy (209, at birth (105 and from the umbilical cord (97 and breast milk (47 were also collected. These samples were tested for 29 PCB congeners and organochlorine pesticides. Results The concentrations of PCB 153 in these media were relatively low in relation to other studies. Σ PCBs measurements in samples taken during the second trimester of pregnancy, at birth and in the umbilical cord were strongly correlated. Specific measurements of PCB 153 and PCB 180 among those subjects with completed sampling of blood samples from mothers and cord samples were significantly correlated. The concentrations of PCBs and pesticides did not differ in relation to prior spontaneous abortion history. There were no organochlorines present in the amniotic fluid at the current level of quantification. Conclusion Pregnant women from the Western Canada region of Calgary, Alberta are exposed to relatively low concentrations of organochlorines. Measurement of maternal blood during the second trimester of pregnancy can reliably estimate the fetal exposure to PCBs. This estimate is reliable for Group 2 and 3 PCBs as well as PCB 153 and PCB 180. The amniotic fluid does not contain

  12. Assessment of High-Resolution Simulations of Precipitation and Temperature Characteristics Over Western Canada Using WRF Model (United States)

    Asong, Z. E.


    Lack of accurate estimates of precipitation are an important limitation for hydrological and earth systems modelling in Canada. Ground-based measurements are inevitably limited, given the large land area and small population density, fail to capture the effects of mountain topography in important runoff-producing areas and suffer from gross inaccuracies associated with cold climate precipitation processes. The capability of the current generation of atmospheric models to represent precipitation is therefore of major interest for hydrological practice. The skill of a high-resolution 4-km convection resolving regional climate model (RCM)―Weather Research and Forecasting (WRF) in capturing the statistics of daily-scale precipitation (P) and temperature (T) over western Canada within the period 2002 - 2013, using observational data sets for comparison is evaluated in this study. We analyze not only the mean pattern of P and T distributions, but also the inter-annual variability and trends in higher order climate statistics such as wet-dry day frequency, spell lengths, 95th percentile daily maximum T, 5th percentile daily minimum T, and 95th percentile daily P are evaluated against ground observations. This preliminary assessment should enable more informed application of high-resolution RCMs for the investigation of current and future changes in socio-economic and environmentally relevant hydro-climatic characteristics over this topographically complex region of western Canada.


    Institute of Scientific and Technical Information of China (English)



    Palaeoerosion sedimentary discontinuity type gold deposit ismajor type gold deposit of western Guangxi. The metallogenic geological condition of this type gold deposit are analyzed, the genesis and metallogenic mechanism are also discussed, the author thinks this type gold ore mining and semlt easy, there are remarkable economic results, and the author proposes that the devolop capability should build up.%古侵蚀沉积间断面型金矿是桂西的主要金矿床类型。文章着重分析该类型金矿成矿地质条件,论述矿床成因及成矿机理,认为此类型金矿易采易冶,经济效益显著,建议加大开发力度。

  14. Sea-floor morphology and sedimentary environments of western Block Island Sound, northeast of Gardiners Island, New York (United States)

    McMullen, Katherine Y.; Poppe, Lawrence J.; Danforth, William W.; Blackwood, Dann S.; Clos, Andrew R.; Parker, Castle E.


    Multibeam-echosounder data, collected during survey H12299 by the National Oceanic and Atmospheric Administration in a 162-square-kilometer area of Block Island Sound, northeast of Gardiners Island, New York, are used along with sediment samples and bottom photography, collected at 37 stations in this area by the U.S. Geological Survey during cruise 2013-005-FA, to interpret sea-floor features and sedimentary environments. These data and interpretations provide important base maps for future studies of the sea floor, focused, for example, on benthic ecology and resource management. The features and sedimentary environments on the sea floor are products of the glacial history and modern tidal regime. Features include bedforms such as sand waves and megaripples, boulders, a large current-scoured depression, exposed glaciolacustrine sediments, and areas of modern marine sediment. Sand covers much of the study area and is often in the form of sand waves and megaripples, which indicate environments characterized by coarse-grained bedload transport. Boulders and gravelly lag deposits, which indicate environments of erosion or nondeposition, are found off the coast of Gardiners Island and on bathymetric highs, probably marking areas where deposits associated with recessional ice-front positions, the northern flank of the terminal moraine, or coastal-plain sediments covered with basal till are exposed. Bottom photographs and video of boulders show that they are commonly covered with sessile fauna. Strong tidal currents have produced the deep scour depression along the northwestern edge of the study area. The eastern side of this depression is armored with a gravel lag. Sea-floor areas characterized by modern marine sediments appear featureless at the 2-meter resolution of the bathymetry and flat to current rippled in the photography. These modern environments are indicative of sediment sorting and reworking.

  15. Reservoirs and water management influence fish mercury concentrations in the western United States and Canada (United States)

    Willacker, James J.; Eagles-Smith, Collin A.; Lutz, Michelle A.; Tate, Michael T.; Lepak, Jesse M.; Ackerman, Josh


    Anthropogenic manipulation of aquatic habitats can profoundly alter mercury (Hg) cycling and bioaccumulation. The impoundment of fluvial systems is among the most common habitat manipulations and is known to increase fish Hg concentrations immediately following impoundment. However, it is not well understood how Hg concentrations differ between reservoirs and lakes at large spatial and temporal scales or how reservoir management influences fish Hg concentrations. This study evaluated total Hg (THg) concentrations in 64,386 fish from 883 reservoirs and 1387 lakes, across the western United States and Canada, to assess differences between reservoirs and lakes, as well as the influence of reservoir management on fish THg concentrations. Fish THg concentrations were 1.4-fold higher in reservoirs (0.13 ± 0.011 μg/g wet weight ± standard error) than lakes (0.09 ± 0.006), though this difference varied among ecoregions. Fish THg concentrations were 1.5- to 2.6-fold higher in reservoirs than lakes of the North American Deserts, Northern Forests, and Mediterranean California ecoregions, but did not differ between reservoirs and lakes in four other ecoregions. Fish THg concentrations peaked in three-year-old reservoirs then rapidly declined in 4–12 year old reservoirs. Water management was particularly important in influencing fish THg concentrations, which were up to 11-times higher in reservoirs with minimum water storage occurring in May, June, or July compared to reservoirs with minimum storage occurring in other months. Between-year changes in maximum water storage strongly influenced fish THg concentrations, but within-year fluctuations in water levels did not influence fish THg concentrations. Specifically, fish THg concentrations increased up to 3.2-fold over the range of between-year changes in maximum water storage in all ecoregions except Mediterranean California. These data highlight the role of reservoir creation and management in influencing fish

  16. A harvest management strategy for Canada geese in the western Mississippi Flyway (United States)

    US Fish and Wildlife Service, Department of the Interior — Management of Canada goose (Branta canadensis) harvest in the Mississippi Flyway became increasingly complex during the 1980s. A strategy for managing harvest was...

  17. Translocation and banding of Aleutian Canada geese in the western Aleutian Islands in 1990 (United States)

    US Fish and Wildlife Service, Department of the Interior — In August 1990, 110 Aleutian Canada geese (Branta canadensis leucopareia) were captured and banded at Buldir Island. Twenty-five of these geese were translocated to...

  18. Discovery of the Western Palearctic bee, Megachile (Pseudomegachile) ericetorum, (Hymenoptera: Megachilidae), in Ontario Canada (United States)

    The bees of North America are very diverse, including over 3500 species. Approximately thirty of these bee species are not native to this continent. Recently another non-native bee, Megachile (Pseudomegachile) ericetorum, was found in a naturalized area in Ontario, Canada. This bee nests in holes...

  19. Age and position of the sedimentary basin of the Ocoee Supergroup western Blue Ridge tectonic province, southern Appalachians

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    Unrug, R.; Unrug, S. (Wright State Univ., Dayton, OH (United States). Dept. of Geological Sciences); Ausich, W.I. (Ohio State Univ., Columbus, OH (United States). Dept. of Geological Sciences); Cuffey, R.J. (Pennsylvania State Univ., University Park, PA (United States). Dept. of Geosciences); Mamet, B.L. (Univ. de Montreal, Quebec (Canada). Dept. de Geologie); Palmes, S.L. (Florida State Univ., Tallahassee, FL (United States). Dept. of Geology)


    The stratigraphic continuity of the Ocoee Supergroup established recently allows one to extrapolate the Paleozoic age of the Walden Creek Group determined on paleontological evidence to the entire Ocoee succession. The Walden Creek Group rocks contain a fossil assemblage of fenestrate bryozoan, algal, trilobite, ostracod, brachiopod and echinozoan fragments and agglutinated foraminifer tests that indicate Silurian or younger Paleozoic age. The fossils occur in carbonate clasts in polymict conglomerates, and debris-flow breccia beds, and in olistoliths of bedded carbonate and shale, and calcarenite turbidite beds. These carbonate lithologies form a minor, but characteristic constituent of the Walden Creek Group. Fossil have been found also in shale and mudstone siliciclastic lithologies of the Walden Creek Group. The fossils are fragmented and poorly preserved because of several cycles of cementation and solution in the carbonate rocks and a pervasive cleavage in the fine-grained siliciclastic rocks. Recently reported Mississippian plant fossils from the Talladega belt indicate widespread occurrence of Middle Paleozoic basins in the Western Blue Ridge. These pull-apart basins formed in the stress field generated by northward movement of Laurentia past the western margin of Gondwana after the Taconian-Famatinian collision in the Ordovician.

  20. Abundance and diversity of sedimentary bacterial communities in a coastal productive setting in the Western Irish Sea (United States)

    O'Reilly, S. S.; Pentlavalli, P.; Flanagan, P. V.; Allen, C. C. R.; Monteys, X.; Szpak, M. T.; Murphy, B. T.; Jordan, S. F.; Kelleher, B. P.


    The bacterial community composition and biomass abundance from a depositional mud belt in the western Irish Sea and regional sands were investigated by phospholipid ester-linked fatty acid profiling, denaturing gradient gel electrophoresis and barcoded pyrosequencing of 16S rRNA genes. The study area varied by water depth (12-111 m), organic carbon content (0.09-1.57% TOC), grain size, hydrographic regime (well-mixed vs. stratified), and water column phytodetrital input (represented by algal polyunsaturated PLFA). The relative abundance of bacterial-derived PLFA (sum of methyl-branched, cyclopropyl and odd-carbon number PLFA) was positively correlated with fine-grained sediment, and was highest in the depositional mud belt. A strong association between bacterial biomass and eukaryote primary production was suggested based on observed positive correlations with total nitrogen and algal polyunsaturated fatty acids. In addition, 16S rRNA genes affiliated to the classes Clostridia and Flavobacteria represented a major proportion of total 16S rRNA gene sequences. This suggests that benthic bacterial communities are also important degraders of phytodetrital organic matter and closely coupled to water column productivity in the western Irish Sea.

  1. Past and future hydro-climatic change and the 2015 drought in the interior of western Canada (United States)

    DeBeer, C. M.; Wheater, H. S.; Pomeroy, J. W.; Stewart, R. E.; Szeto, K.; Brimelow, J.; Chun, K. P.; Masud, M. B.; Bonsal, B. R.


    The interior of western Canada has experienced rapid and severe hydro-climatic change in recent decades. This is projected to continue in future. Since 1950, mean annual air temperature has increased by 2 °C (4 °C increase in winter daily means) with associated changes in cryospheric regime. Changes in precipitation have varied regionally; in the Prairies there has been a decrease in winter precipitation, shift from snowfall to rainfall, and increased clustering of summer rainfall events into multiple day storms. Regionally, river discharge indicates an earlier spring freshet and increased incidence of rain-on-snow peak flow events, but otherwise mixed responses due to multiple process interactions. In winter/spring 2015, persistent anomalous ridging conditions developed over western North America causing widespread drought. This produced abnormally warm and dry conditions over the Rocky Mountain headwaters of the Mackenzie and Saskatchewan Rivers, resulting in low spring snowpacks that melted earlier than normal and were followed by an atypical lack of spring rainfall. By summer 2015, most of western Canada was subject to extreme drought conditions leading to record dry soil moisture conditions in parts of the Prairies during a key crop growth time, streamflows that were greatly diminished, and extensive wildfires across the Boreal Forest. The importance of the warmer winter to this drought and the contextual trend for increasing winter warmth provide new insight into the impact of climate warming on droughts in cold regions. This talk will discuss efforts by the Changing Cold Regions Network (CCRN; to understand and diagnose the 2015 drought, its potential linkages with the concurrent California drought and other continental events, and its relevance in the context of historical and predicted future climate change.

  2. Large sedimentary aquifer system and sustainable management: investigations of hydrogeological and geochemical variations in Eocene sand aquifer, south western France (United States)

    Malcuit, E.; Negrel, P. J.; Petelet-Giraud, E.; Durst, P.


    In the sedimentary Aquitaine Basin, the Eocene Sand Aquifer system, mostly confined, represents strategic resources for drinking water, irrigation, gas storage and geothermal resources. Therefore, its quantity and quality issues are essential for the sustainable management in this large region that extends over 116,000 km2 (i.e. one-fifth of the French territory). The Eocene Sand Aquifer system comprises at least five aquifers: Paleocene, Eocene infra-molassic sands, early Eocene, middle Eocene, and late Eocene. The extension and thickness of Eocene aquifer layers and negative confined layers vary throughout the basin, from several tens of metres to a hundred metres. The deposit sequences characterizing the Eocene Aquifer System are progradational westward from detrital deposits to carbonates. Eocene sands and Eocene limestones are hydraulically connected and covered by an aquiclude of up to several hundred metres thick of molassic sediments. The groundwater recharge is assumed to occur through the Eocene outcrops located in the north and north-east, and in the south east in contact with the Montagne Noire as well as by vertical leakage from the upper and lower aquifers. Another recharge is suspected in the south near the Petites Pyrenees. According to isotopic data, both present-day recharge and old recharge (16-35 ky) can be evidenced. The north and south evolutions of the piezometric surface are different. In the north, because of years of pumping, a trough in the potentiometric surface has been formed. The piezometric decline is roughly one meter per year in the depression centre. In the south, the decline of the water table is roughly half a meter per year. Furthermore, in the south part, around two sites of gas storage, significant fluctuations of the potentiometric surface are superimposed to the variations resulting from water abstraction, due to the injection and abstraction of gas. However, a major difficulty for the sustainable management is the lack of

  3. Organic carbon and nitrogen isotopes in surface sediments from the western Arctic Ocean and their implications for sedimentary environments

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhihua; SHI Xuefa; CAI Deling; HAN Yibing; YANG Zuosheng


    Surface sediments from the Chukchi Sea and adjacent arctic deep sea were investigated for organic carbon and nitrogen isotopes (in δ13Corg and δ15Norg) as well as biogenic silica (BSiO2). δ13Corg and δ15Norg values of surface sediments in the study area fall between the end-member values of marine and terrestrial organic matter from the surrounding lands and seas, their variations reflect the changes of marine productivity and terrestrial supply in the study area. BSiO2 shows a similar distribution pattern with δ13Corg and δ15Norg, and can be used as an indicator of marine productivity. In the central-west Chukchi Sea and the Chukchi Rise, sediments have higher δ13Corg, δ15Norg and BSiO2 values, indicating the region has high marine productivity influenced by the nutrient-rich branches of the Pacific waters. In the coastal zone off northwestern Alaska, δ13Corg and δ15Norg values become lighter, indicating a weakening marine productivity and an increasing terrigenous supply due to the effects of the least nutrient-rich branch of the Pacific waters. In the north and the northeast of the study area (including the Chukchi Plateau, the Canada Basin and the Beaufort shelf), δ13Corg, δ15Norg and BSiO2 have the lowest values, and the terrigenous organic matter becomes dominant in surface sediments because this region has the longest ice-covered duration, the least nutrient-rich seawater and the increasing supply of terrestrial materials from the Mackenzie River and the northern Alaska under the action of the clockwise Beaufort gyre. Because the subarctic Pacific waters are continuously discharged into the central basin of the Arctic Ocean through the study area, the nutrient pool in the Chukchi Sea can be considered as a typical open system, the ratio of δ15N to BSiO2 content show some tracers that the level of nutrient utilization is contrary to nutrient supply and marine productivity formed in seawater.

  4. Leeward bank margin Halimeda meadows and draperies and their sedimentary importance on the western Great Bahama Bank slope (United States)

    Freile, D.; Milliman, J. D.; Hillis, L.


    Bryopsidalean algal meadows in water depths of 20 40 m on the leeward side of western Great Bahama Bank (WGBB) lie between non-skeletal-dominated sand flats on the bank top to the east and a cemented steep escarpment to the west. The meadows contain dense populations of rhipsalian Halimeda species, as well as Udotea and Rhipocephalus. Extensive populations of other Halimeda species (opuntioids) occur at greater depths on the cemented rocky escarpment, growing as drapes or vines rather than as upright thalli. These meadows and draperies are important sources of coarse-grained carbonate sediments. This is shown by (1) deeper bank-edge sediments (30 60 m) containing considerably more Halimeda fragments than do the bank top, non-skeletal sands, and (2) the coarser fraction of slope sediments (down to 200 m) dominated by Halimeda plates, partly or extensively altered and internally cemented by magnesian calcite and aragonite. A transect across the bank margin from bank top (bank-edge habitats approximates that in the Great Barrier Reef or off Indonesia and Nicaragua in similar water depths. The apparent lack of thick sediment accumulation in WGBB compared to that seen elsewhere may reflect the high rates of downslope transport off Great Bahama Bank.

  5. Compositional variation of glauconites in Upper Cretaceous-Paleogene sedimentary iron-ore deposits in South-eastern Western Siberia (United States)

    Rudmin, Maxim; Banerjee, Santanu; Mazurov, Aleksey


    Glauconite occurs either as unaltered greenish or as altered brownish variety in Upper Cretaceous-Palaeocene sediments in the southeastern corner of Western Siberia. Studied section within the Bakchar iron-ore deposit includes Ipatovo, Slavgorod, Gan'kino and Lyulinvor formations, which are represented by sandstones, siltstones, claystones and oolitic ironstones of coastal-marine facies. The origin of unaltered glauconite is explained by the ;verdissement theory;. Transgressions during Lower Coniacian, Santonian and Campanian favored the formation of unaltered glauconites in dysoxic to anoxic conditions. Subaerial exposure of glauconite resulted in leaching of potassium, oxidation of iron and formation of iron hydroxides in Upper Coniacian, Maastrichtian and Palaeocene. Glauconite ultimately converts to leptochlorite and hydrogoethite by this alteration. Abundant microscopic gold inclusions, besides sulphides, sulphates, oxides and silicates characterize this glauconite. Mineral inclusions include precious, rare metals and non-ferrous metals. The concentration of gold in glauconite may be as high as 42.9 ppb. Abundant inclusions of various compositions in glauconites indicate enrichment of marine sediments in precious and non-precious metals. While major element composition of glauconites is affected by subaerial exposure, the broadly similar micro-inclusions in both altered and unaltered varieties are possibly related to the comparatively immobile nature of REE and trace elements.


    Institute of Scientific and Technical Information of China (English)


    20160899 Chen Ji(School of Energy Resources,China University of Geosciences(Beijing),Beijing 100083,China);Jiang Zaixing Sedimentary Facies Characteristics and Palaeoenvironment of Jurassic Yangye Forma-

  7. Early Cretaceous stratigraphy, paleontology, and sedimentary tectonics in Paris overthrust foredeep (western Wyoming and southeastern Idaho) compared with Quaternary features of indo-gangetic plain

    Energy Technology Data Exchange (ETDEWEB)

    Dorr, J.A. Jr.


    Fluviatile clastics of the nonmarine, early Cretaceous Gannett and Wayan groups were deposited on wet alluvial megafans and on intervening interfan piedmont slopes which declined eastward into more poorly drained lowlands from a western highland source area uplifted episodically by movements of the Paris overthrust. Lacustrine episodes of deposition intercalated Peterson and Draney limestones with Gannett fluvial clastics. Westward marine transgressions (Skull Creek, Mowry) intercalated mixed lacustrine and brackish facies (Smiths and Cokedale formations) into Wayan fluviatile clastics. Newly discovered fossil vertebrate and invertebrate materials (all fragmentary but identifiable) include: Gannett Group - large reptiles including turtles; Thomas Fork Formation - freshwater gastropods and unionid pelecypods, gastroliths, two types of turtles, large reptilian fragments (dinosaur), and abundant dinosaur eggshell fragments; Wayan Formation - perennially aquatic snails, turtles, unidentifiable large reptiles, two types of crocodilians, an iguanodontid dinosaur (Tenontosaurus), an ankylosaurian dinosaur, a large ornithopod dinosaur, gastroliths, abundant and ubiquitous dinosaur eggshell fragments (numerous types and sizes), and miscellaneous unidentifiable small vertebrate bone fragments. A census of analogous modern reptile reproductive behaviors supports the conclusion that the Wayan, and probably also the Gannett, alluvial fan environments were used as upland breeding grounds by dinosaurs and perhaps other reptiles. Comparison of these Early Cretaceous data with observations on the tectonic setting, sedimentology, and biology of the Quaternary indo-gangetic plain suggests many close analogies between the two sedimentary tectonic settings.

  8. Nematode diversity and its relation to the quantity and quality of sedimentary organic matter in the deep Nazaré Canyon, Western Iberian Margin (United States)

    Ingels, Jeroen; Kiriakoulakis, Konstadinos; Wolff, George A.; Vanreusel, Ann


    Samples collected in the deep Nazaré Canyon and at the adjacent slope, during the HERMES RRS Discovery D297 cruise (2005), were analysed for metazoan meiofauna, nematode structure and diversity and its relation to quality and quantity of sedimentary organic material. The amount and quality of organic matter available for direct consumption was much higher in the canyon compared to the slope and positively correlated with high nematode abundances (795-1171 ind. 10 cm -2) and biomass (93.2-343.5 μg dry weight 10 cm -2), thus leading to higher standing stocks. Canyon nematode assemblages also showed particular adaptations (e.g. higher trophic complexity, variability of nematode morphology, and presence of opportunistic genera) to canyon conditions, particularly in the deeper sediment layers. The Nazaré Canyon's nematode diversity was slightly lower than that of the adjacent slope and its assemblages were characterised by a higher dominance of certain genera. Still, the canyon contributes considerably to total Western Iberian Margin diversity due to different assemblages present compared to the slope. Furthermore, the harsh conditions in terms of hydrodynamic disturbance and the high organic matter flux are likely to have a negative impact on the establishment of species rich meiobenthic communities, especially in the canyon axis.

  9. Paleozoic sedimentary rocks in the Red Dog Zn-Pb-Ag district and vicinity, western Brooks Range, Alaska: provenance, deposition, and metallogenic significance (United States)

    Slack, John F.; Dumoulin, Julie A.; Schmidt, J.M.; Young, L.E.; Rombach, Cameron


    Geochemical analyses of Paleozoic sedimentary rocks in the western Brooks Range reveal a complex evolutionary history for strata surrounding the large Zn-Pb-Ag deposits of the Red Dog district. Data for major elements, trace elements, and rare earth elements (REE) were obtained on 220 samples of unaltered and unmineralized siliciclastic rocks from the Upper Devonian-Lower Mississippian Endicott Group (Hunt Fork Shale, Noatak Sandstone, Kanayut Conglomerate, Kayak Shale), the overlying Carboniferous Lisburne Group (Kuna Formation, unnamed drowned shelf facies), and the Pennsylvanian-Permian Siksikpuk Formation. Major base metal sulfide deposits of the region are present only in the Kuna Formation, which in the Red Dog district comprises siliceous black shale and black chert, minor limestone (calcareous radiolarite), and sparse lithic turbidite and bedded siliceous rock. Gray and rare black shales of the Kayak Shale and common black shales of the Kuna Formation are anomalously low in iron (avg Fe/Ti = 6.25 and 6.34, respectively) relative to other Paleozoic shales in the region (9.58-10.6) and to average shales worldwide (10.1-10.5). In contrast, the bedded siliceous rocks contain appreciable hematite (avg Fe/Ti = 35.0) and high U/Ti and REE/Ti ratios that are interpreted to reflect low amounts of detrital material and a major Fe-rich eolian component.

  10. First record of eocene bony fishes and crocodyliforms from Canada's Western Arctic.

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    Jaelyn J Eberle

    Full Text Available BACKGROUND: Discovery of Eocene non-marine vertebrates, including crocodylians, turtles, bony fishes, and mammals in Canada's High Arctic was a critical paleontological contribution of the last century because it indicated that this region of the Arctic had been mild, temperate, and ice-free during the early - middle Eocene (∼53-50 Ma, despite being well above the Arctic Circle. To date, these discoveries have been restricted to Canada's easternmost Arctic - Ellesmere and Axel Heiberg Islands (Nunavut. Although temporally correlative strata crop out over 1,000 km west, on Canada's westernmost Arctic Island - Banks Island, Northwest Territories - they have been interpreted as predominantly marine. We document the first Eocene bony fish and crocodyliform fossils from Banks Island. PRINCIPAL FINDINGS: We describe fossils of bony fishes, including lepisosteid (Atractosteus, esocid (pike, and amiid, and a crocodyliform, from lower - middle Eocene strata of the Cyclic Member, Eureka Sound Formation within Aulavik National Park (∼76°N. paleolat.. Palynology suggests the sediments are late early to middle Eocene in age, and likely spanned the Early Eocene Climatic Optimum (EECO. CONCLUSIONS/SIGNIFICANCE: These fossils extend the geographic range of Eocene Arctic lepisosteids, esocids, amiids, and crocodyliforms west by approximately 40° of longitude or ∼1100 km. The low diversity bony fish fauna, at least at the family level, is essentially identical on Ellesmere and Banks Islands, suggesting a pan-High Arctic bony fish fauna of relatively basal groups around the margin of the Eocene Arctic Ocean. From a paleoclimatic perspective, presence of a crocodyliform, gar and amiid fishes on northern Banks provides further evidence that mild, year-round temperatures extended across the Canadian Arctic during early - middle Eocene time. Additionally, the Banks Island crocodyliform is consistent with the phylogenetic hypothesis of a Paleogene divergence

  11. Sedimentary halogens and noble gases within Western Antarctic xenoliths: Implications of extensive volatile recycling to the sub continental lithospheric mantle (United States)

    Broadley, Michael W.; Ballentine, Chris J.; Chavrit, Déborah; Dallai, Luigi; Burgess, Ray


    Recycling of marine volatiles back into the mantle at subduction zones has a profound, yet poorly constrained impact on the geochemical evolution of the Earth's mantle. Here we present a combined noble gas and halogen study on mantle xenoliths from the Western Antarctic Rift System (WARS) to better understand the flux of subducted volatiles to the sub continental lithospheric mantle (SCLM) and assess the impact this has on mantle chemistry. The xenoliths are extremely enriched in the heavy halogens (Br and I), with I concentrations up to 1 ppm and maximum measured I/Cl ratios (85.2 × 10-3) being ∼2000 times greater than mid ocean ridge basalts (MORB). The Br/Cl and I/Cl ratios of the xenoliths span a range from MORB-like ratios to values similar to marine pore fluids and serpentinites, whilst the 84Kr/36Ar and 130Xe/36Ar ratios range from modern atmosphere to oceanic sediments. This indicates that marine derived volatiles have been incorporated into the SCLM during an episode of subduction related metasomatism. Helium isotopic analysis of the xenoliths show average 3He/4He ratios of 7.5 ± 0.5 RA (where RA is the 3He/4He ratio of air = 1.39 × 10-6), similar to that of MORB. The 3He/4He ratios within the xenoliths are higher than expected for the xenoliths originating from the SCLM which has been extensively modified by the addition of subducted volatiles, indicating that the SCLM beneath the WARS must have seen a secondary alteration from the infiltration and rise of asthenospheric fluids/melts as a consequence of rifting and lithospheric thinning. Noble gases and halogens within these xenoliths have recorded past episodes of volatile interaction within the SCLM and can be used to reconstruct a tectonic history of the WARS. Marine halogen and noble gas signatures within the SCLM xenoliths provide evidence for the introduction and retention of recycled volatiles within the SCLM by subduction related metasomatism, signifying that not all volatiles that survive

  12. Climate change-associated trends in net biomass change are age dependent in western boreal forests of Canada. (United States)

    Chen, Han Y H; Luo, Yong; Reich, Peter B; Searle, Eric B; Biswas, Shekhar R


    The impacts of climate change on forest net biomass change are poorly understood but critical for predicting forest's contribution to the global carbon cycle. Recent studies show climate change-associated net biomass declines in mature forest plots. The representativeness of these plots for regional forests, however, remains uncertain because we lack an assessment of whether climate change impacts differ with forest age. Using data from plots of varying ages from 17 to 210 years, monitored from 1958 to 2011 in western Canada, we found that climate change has little effect on net biomass change in forests ≤ 40 years of age due to increased growth offsetting increased mortality, but has led to large decreases in older forests due to increased mortality accompanying little growth gain. Our analysis highlights the need to incorporate forest age profiles in examining past and projecting future forest responses to climate change.

  13. Spatial and temporal patterns of mercury concentrations in freshwater fish across the Western United States and Canada (United States)

    Eagles-Smith, Collin A.; Ackerman, Josh; Willacker, James J.; Tate, Michael T.; Lutz, Michelle A; Fleck, Jacob; Stewart, Robin; Wiener, James G.; Evers, David C.; Lepak, Jesse M; Davis, Jay A; Pritz, Colleen Flanagan


    Methylmercury contamination of fish is a global threat to environmental health. Mercury (Hg) monitoring programs are valuable for generating data that can be compiled for spatially broad syntheses to identify emergent ecosystem properties that influence fish Hg bioaccumulation. Fish total Hg (THg) concentrations were evaluated across the Western United States (US) and Canada, a region defined by extreme gradients in habitat structure and water management. A database was compiled with THg concentrations in 96,310 fish that comprised 206 species from 4262 locations, and used to evaluate the spatial distribution of fish THg across the region and effects of species, foraging guilds, habitats, and ecoregions. Areas of elevated THg exposure were identified by developing a relativized estimate of fish mercury concentrations at a watershed scale that accounted for the variability associated with fish species, fish size, and site effects. THg concentrations in fish muscle ranged between 0.001 and 28.4 (μg/g wet weight (ww)) with a geometric mean of 0.17. Overall, 30% of individual fish samples and 17% of means by location exceeded the 0.30 μg/g ww US EPA fish tissue criterion. Fish THg concentrations differed among habitat types, with riverine habitats consistently higher than lacustrine habitats. Importantly, fish THg concentrations were not correlated with sediment THg concentrations at a watershed scale, but were weakly correlated with sediment MeHg concentrations, suggesting that factors influencing MeHg production may be more important than inorganic Hg loading for determining fish MeHg exposure. There was large heterogeneity in fish THg concentrations across the landscape; THg concentrations were generally higher in semi-arid and arid regions such as the Great Basin and Desert Southwest, than in temperate forests. Results suggest that fish mercury exposure is widespread throughout Western US and Canada, and that species, habitat type, and region play an important

  14. Tectono-sedimentary evolution and new sections across the western Gran Sasso d'Italia (Central Apennines) (United States)

    Cardello, Giovanni Luca; Bernoulli, Daniel; Doglioni, Carlo


    During Jurassic-Cretaceous times, the area of the central Apennines was part of a large, Bahamian-type carbonate platform-basin system, whereby the area of the Gran Sasso was situated between the carbonate platform of Latium and the Abruzzi in the west and the deep basinal area of Marche-Umbria to the east. This transitional area experienced 1. Early Jurassic rifting of the Adriatic margin, leading to the opening of the Ligurian branch of Tethys; 2. prolonged thermal subsidence of the carbonate-platform slope and base-of-slope in the Jurassic-Cretaceous; 3. decollement along Triassic evaporites, thrusting and folding during the Neogene formation of the arc of Gran Sasso and 4. post-nappe normal faulting persisting to this date. Mapping of the western part of the E-W-trending ridge of the Gran Sasso d'Italia has yielded the following results: 1 - The early Jurassic rifting event led to the segmentation of the platform slope into structural highs (Corno Grande and Acqua San Franco) and basins (Pizzo d'Intermesoli, M. Corvo) as suggested by the pronounced differences in thickness of the early-middle Liassic syn-rift sediments (Corniola Formation). Whereas the Acqua San Franco structural high in the west was buried during the Toarcian, the Corno Grande high in the east persisted throughout Mesozoic times at least into the early Tertiary. The longevity and possible tectonic reactivation of the submarine topography, inherited from early Liassic rifting, persisted way into Jurassic-Middle Miocene as suggested by the pronounced differences in thickness of the Jurassic base-of-slope (Corno Piccolo Formation) and Oligocene to Miocene distal ramp sediments, and sequences punctuated by stratigraphic gaps on the highs. 2 - During the Tertiary orogeny of the Apennines, the inherited Mesozoic structures evolved into N-S trending transfer zones between the individual thrusts and folds over- and underthrusting the more external Laga unit. The axis of the frontal anticline and the

  15. Transgenic oilseed rape along transportation routes and port of Vancouver in western Canada. (United States)

    Yoshimura, Yasuyuki; Beckie, Hugh J; Matsuo, Kazuhito


    The occurrence of transgenic herbicide-resistant oilseed rape (Brassica napus) in ruderal (non-crop disturbed) areas has not been investigated previously in Canada. The primary objective of this study was to document their occurrence in two main ruderal areas (along railways and roads) in the province of Saskatchewan, where half of all oilseed rape is grown, and at the port of Vancouver, British Columbia on the west coast of Canada, where most oilseed rape destined for export is transported by rail. During the 2005 growing season, leaf samples of oilseed rape plants were collected at randomly-selected sites along railways and roads across Saskatchewan ecoregions and at Vancouver; infestation area, density, and plant height of oilseed rape were measured at each site. The presence of the glyphosate and glufosinate resistance traits was determined using test strips. The infestation area of oilseed rape, averaged across 155 sampled sites in the Saskatchewan survey, was markedly smaller in populations along railways than roads; in contrast, infestation area averaged across 54 sites in the Vancouver survey was greater for populations along railways than roads. In both surveys, mean plant density was greater for populations found along railways than roads. Two-thirds of oilseed rape plants sampled across Saskatchewan ecoregions and at Vancouver were transgenic, although the relative proportion of plants with the glyphosate or glufosinate resistance trait varied between surveys. Frequency of occurrence of transgenic plants in ruderal areas was similar to the proportion of the oilseed rape area planted with transgenic cultivars in the recent preceding years. A single transgenic B. rapa x B. napus hybrid was found along a road in Vancouver, confirming the relatively high probability of hybridization between these two Brassica species. With current control measures, transgenic oilseed rape populations may persist and spread in these ruderal areas.

  16. Predator Bounties in Western Canada Cause Animal Suffering and CompromiseWildlife Conservation Efforts

    Directory of Open Access Journals (Sweden)

    Gilbert Proulx


    Full Text Available Although predation bounty programs (rewards offered for capturing or killing an animal ended more than 40 years ago in Canada, they were reintroduced in Alberta in 2007 by hunting, trapping, and farming organizations, municipalities and counties, and in 2009 in Saskatchewan, by municipal and provincial governments and the Saskatchewan Cattlemen’s Association. Bounty hunters use inhumane and non-selective killing methods such as shooting animals in non-vital regions, and killing neck snares and strychnine poisoning, which cause suffering and delayed deaths. They are unselective, and kill many non-target species, some of them at risk. Predator bounty programs have been found to be ineffective by wildlife professionals, and they use killing methods that cause needless suffering and jeopardize wildlife conservation programs. Our analysis therefore indicates that government agencies should not permit the implementation of bounty programs. Accordingly, they must develop conservation programs that will minimize wildlife-human conflicts, prevent the unnecessary and inhumane killing of animals, and ensure the persistence of all wildlife species.

  17. Topographic Indices and Yield Variability in a Rolling Landscape of Western Canada

    Institute of Scientific and Technical Information of China (English)

    CHI Bao-Liang; BING Cheng-Si; F.WALLEY; T.YATES


    Understanding the relationships between topographic indices and crop yield variability is important for soil management and crop production in rolling landscape.Two agricultural fields at Alvena and Hepburn,Saskatchewan,Canada were selected to examine how topographic indices were related to wheat yield under two topographic and weather conditions in the Canadian prairies.The landscapes of the two sites are classified as hummocky and the dominant soil type is an Aridic Ustoll.The relationships among yield,topography,soil,and weather were analyzed using wheat (Triticum aestivum L.)grain yield from Alvena in 2001 (dry year) and 2004 (wet year) and from Hepburn in 1998 (dry year).Topographic/soil indices included relative elevation,wetness index,upslope length,curvature,soil organic matter,and soil moisture storage before seeding.The results indicated that,in the dry years,the correlation coefficients between upslope length and grain yield were 0.79 for the typical rolling landscape (Alvena) in 2001 and 0.73 for shallow gentle rolling landscape (Hepburn) in 1998.In the wet year (2004),the relationships between yield and topographic/soil attributes were not as strong as in dry years.Therefore,upslope length was the best yield indicator for the two landscapes in dry years,whereas no topographic indices were highly correlated to crop yield in wet years.Those topographic indices seemed useful in identifying the yield variability and delineating the proper management zone.

  18. Geochemistry of host rocks in the Howards Pass district, Yukon-Northwest Territories, Canada: implications for sedimentary environments of Zn-Pb and phosphate mineralization (United States)

    Slack, John F.; Falck, Hendrik; Kelley, Karen D.; Xue, Gabriel G.


    Detailed lithogeochemical data are reported here on early Paleozoic sedimentary rocks that host the large Howards Pass stratiform Zn-Pb deposits in Yukon-Northwest Territories. Redox-sensitive trace elements (Mo, Re, V, U) and Ce anomalies in members of the Duo Lake Formation record significant environmental changes. During the deposition of lower footwall units (Pyritic siliceous and Calcareous mudstone members), bottom waters were anoxic and sulphidic, respectively; these members formed in a marginal basin that may have become increasingly restricted with time. Relative to lower members, a major environmental change is proposed for deposition of the overlying Lower cherty mudstone member, which contains phosphorite beds up to ∼0.8 m thick in the upper part, near the base of the Zn-Pb deposits. The presence of these beds, together with models for modern phosphorite formation, suggests P input from an upwelling system and phosphorite deposition in an upper slope or outer shelf setting. The overlying Active mudstone member contains stratabound to stratiform Zn-Pb deposits within black mudstone and gray calcareous mudstone. Data for unmineralized black mudstone in this member indicate deposition under diverse redox conditions from suboxic to sulphidic. Especially distinctive in this member are uniformly low ratios of light to heavy rare earth elements that are unique within the Duo Lake Formation, attributed here to the dissolution of sedimentary apatite by downward-percolating acidic metalliferous brines. Strata that overlie the Active member (Upper siliceous mudstone member) consist mainly of black mudstone with thin (0.5–1.5 cm) laminae of fine-grained apatite, recording continued deposition on an upper slope or outer shelf under predominantly suboxic bottom waters. Results of this study suggest that exploration for similar stratiform sediment-hosted Zn-Pb deposits should include the outer parts of ancient continental margins, especially at and near

  19. Geochemistry of host rocks in the Howards Pass district, Yukon-Northwest Territories, Canada: implications for sedimentary environments of Zn-Pb and phosphate mineralization (United States)

    Slack, John F.; Falck, Hendrik; Kelley, Karen D.; Xue, Gabriel G.


    Detailed lithogeochemical data are reported here on early Paleozoic sedimentary rocks that host the large Howards Pass stratiform Zn-Pb deposits in Yukon-Northwest Territories. Redox-sensitive trace elements (Mo, Re, V, U) and Ce anomalies in members of the Duo Lake Formation record significant environmental changes. During the deposition of lower footwall units (Pyritic siliceous and Calcareous mudstone members), bottom waters were anoxic and sulphidic, respectively; these members formed in a marginal basin that may have become increasingly restricted with time. Relative to lower members, a major environmental change is proposed for deposition of the overlying Lower cherty mudstone member, which contains phosphorite beds up to ˜0.8 m thick in the upper part, near the base of the Zn-Pb deposits. The presence of these beds, together with models for modern phosphorite formation, suggests P input from an upwelling system and phosphorite deposition in an upper slope or outer shelf setting. The overlying Active mudstone member contains stratabound to stratiform Zn-Pb deposits within black mudstone and gray calcareous mudstone. Data for unmineralized black mudstone in this member indicate deposition under diverse redox conditions from suboxic to sulphidic. Especially distinctive in this member are uniformly low ratios of light to heavy rare earth elements that are unique within the Duo Lake Formation, attributed here to the dissolution of sedimentary apatite by downward-percolating acidic metalliferous brines. Strata that overlie the Active member (Upper siliceous mudstone member) consist mainly of black mudstone with thin (0.5-1.5 cm) laminae of fine-grained apatite, recording continued deposition on an upper slope or outer shelf under predominantly suboxic bottom waters. Results of this study suggest that exploration for similar stratiform sediment-hosted Zn-Pb deposits should include the outer parts of ancient continental margins, especially at and near stratigraphic

  20. Advancing team-based primary health care: a comparative analysis of policies in western Canada. (United States)

    Suter, Esther; Mallinson, Sara; Misfeldt, Renee; Boakye, Omenaa; Nasmith, Louise; Wong, Sabrina T


    We analyzed and compared primary health care (PHC) policies in British Columbia, Alberta and Saskatchewan to understand how they inform the design and implementation of team-based primary health care service delivery. The goal was to develop policy imperatives that can advance team-based PHC in Canada. We conducted comparative case studies (n = 3). The policy analysis included: Context review: We reviewed relevant information (2007 to 2014) from databases and websites. Policy review and comparative analysis: We compared and contrasted publically available PHC policies. Key informant interviews: Key informants (n = 30) validated narratives prepared from the comparative analysis by offering contextual information on potential policy imperatives. Advisory group and roundtable: An expert advisory group guided this work and a key stakeholder roundtable event guided prioritization of policy imperatives. The concept of team-based PHC varies widely across and within the three provinces. We noted policy gaps related to team configuration, leadership, scope of practice, role clarity and financing of team-based care; few policies speak explicitly to monitoring and evaluation of team-based PHC. We prioritized four policy imperatives: (1) alignment of goals and policies at different system levels; (2) investment of resources for system change; (3) compensation models for all members of the team; and (4) accountability through collaborative practice metrics. Policies supporting team-based PHC have been slow to emerge, lacking a systematic and coordinated approach. Greater alignment with specific consideration of financing, reimbursement, implementation mechanisms and performance monitoring could accelerate systemic transformation by removing some well-known barriers to team-based care.

  1. Net aboveground biomass declines of four major forest types with forest ageing and climate change in western Canada's boreal forests. (United States)

    Chen, Han Y H; Luo, Yong


    Biomass change of the world's forests is critical to the global carbon cycle. Despite storing nearly half of global forest carbon, the boreal biome of diverse forest types and ages is a poorly understood component of the carbon cycle. Using data from 871 permanent plots in the western boreal forest of Canada, we examined net annual aboveground biomass change (ΔAGB) of four major forest types between 1958 and 2011. We found that ΔAGB was higher for deciduous broadleaf (DEC) (1.44 Mg ha(-1)  year(-1) , 95% Bayesian confidence interval (CI), 1.22-1.68) and early-successional coniferous forests (ESC) (1.42, CI, 1.30-1.56) than mixed forests (MIX) (0.80, CI, 0.50-1.11) and late-successional coniferous (LSC) forests (0.62, CI, 0.39-0.88). ΔAGB declined with forest age as well as calendar year. After accounting for the effects of forest age, ΔAGB declined by 0.035, 0.021, 0.032 and 0.069 Mg ha(-1)  year(-1) per calendar year in DEC, ESC, MIX and LSC forests, respectively. The ΔAGB declines resulted from increased tree mortality and reduced growth in all forest types except DEC, in which a large biomass loss from mortality was accompanied with a small increase in growth. With every degree of annual temperature increase, ΔAGB decreased by 1.00, 0.20, 0.55 and 1.07 Mg ha(-1)  year(-1) in DEC, ESC, MIX and LSC forests, respectively. With every cm decrease of annual climatic moisture availability, ΔAGB decreased 0.030, 0.045 and 0.17 Mg ha(-1)  year(-1) in ESC, MIX and LSC forests, but changed little in DEC forests. Our results suggest that persistent warming and decreasing water availability have profound negative effects on forest biomass in the boreal forests of western Canada. Furthermore, our results indicate that forest responses to climate change are strongly dependent on forest composition with late-successional coniferous forests being most vulnerable to climate changes in terms of aboveground biomass. © 2015 John Wiley & Sons Ltd.

  2. Western Canada study of animal health effects associated with exposure to emissions from oil and natural gas field facilities. Study design and data collection II. Location of study herds relative to the oil and gas industry in Western Canada. (United States)

    Waldner, Cheryl L


    During the late part of 2000 and early months of 2001, project veterinarians recruited 205 beef herds to participate in a study of the effects of emissions from the upstream oil and gas industry on cattle reproduction and health. Researchers developed herd-selection criteria to optimize the range of exposure to facilities, including oil and gas wells, battery sites, and gas-gathering and gas-processing facilities across the major cattle-producing areas of Western Canada. Herds were initially selected on the basis of a ranking system of exposure potential on the basis of herd-owner reports of the locations of their operations in relation to oil and gas industry facilities. At the end of the study, researchers summarized data obtained from provincial regulatory agencies on facility location and reported flaring and venting volumes for each herd and compared these data to the original rankings of herd-exposure potential. Through this selection process, the researchers were successful in obtaining statistically significant differences in exposure to various types of oil and gas facility types and reported emissions among herds recruited for the study.

  3. Sedimentological and sequence stratigraphic analysis of Carboniferous deposits in western Libya: Recording the sedimentary response of the northern Gondwana margin to climate and sea-level changes (United States)

    Fröhlich, Sebastian; Petitpierre, Laurent; Redfern, Jonathan; Grech, Paul; Bodin, Stéphane; Lang, Simon


    Detailed sedimentological and sequence stratigraphic analysis of Carboniferous (Tournaisian to Moscovian) strata exposed in the north-western Murzuq Basin and southern Ghadames Basin, western Libya, provides new insights into the sedimentary response of the northern Gondwana margin to climate and sea-level change. The Lower Carboniferous Marar and Assedjefar Formations can be divided into five depositional sequences of 3rd order. In total 27 facies types are defined, grouped into four facies associations: offshore shales, shallow marine clastics, fluvial sandstones and marine carbonates. The bulk of the Lower Carboniferous interval is dominated by an alternation of offshore shales and shallow marine clastics, which were deposited during the transgressive and highstand systems tracts. The clastic deposits mostly consist of laterally persistent coarsening and thickening upward cycles with a common succession from basal hummocky cross-stratified sandstones to ripple-laminated sandstones, capped by multidirectional cross-stratified sandstones. Within the lowstand systems tracts, lenticular sandbodies have been identified, which vary in thickness from 1.5 m (ca. 40 m wide) to 50 m (ca. 1.5 km wide). These are interpreted to be fluvial channel complexes based on their geometry, erosive base, and presence of thick stacked sandstones with unidirectional planar and trough cross-bedding, the absence of bioturbation and occurrence of land plant fragments. These channel complexes mostly cut down into offshore shales, and are interpreted to be bound at the base by sequence boundaries. Palaeogeographic maps generated for each lowstand system show the location and palaeoflow direction of these fluvial channel complexes. They are interpreted to represent large incised valleys filled with thick fluvial sandstones. Their identification and distribution indicates repeated exposure of large areas of western Libya, most-likely controlled by major eustatic sea-level changes. The

  4. The Nitrogen Balance of Three Long-term Agroecosystems on a Boreal Soil in Western Canada

    Energy Technology Data Exchange (ETDEWEB)

    Ross, Shirley M.; Izaurralde, Roberto C.; Janzen, H. H.; Robertson, J. A.; Mcgill, William B.


    Nitrogen (N) budgets can be used to quantify the flows of N in agroecosystems and to account for differences in losses and retention of N. The objective of our study was to develop 24-year N budgets for three diverse cropping systems on a boreal soil at Breton, Alberta, Canada: AER an agroecological 8-year rotation, with N inputs from legumes [fababean (Vicia faba L.), red clover (Trifolium pratense L.), alfalfa (Medicago sativa L.)] and manure; CF - a continuous perennial grass legume forage system, with N inputs from fertilizer (18 kg N ha-1 yr-1) and white clover (Trifolium repens L.); and CG - a continuous annual grain system, with N fertilizer (90 kg N ha-1 yr-1). We were able to compile detailed N budgets, demonstrate accumulation of soil N, and attribute differences in N flow and permanence to treatment effects. For AER and CG, net inputs almost exactlymatched gains in soil N. The AER system had the highest N flow and the largest net N accumulation. Soil total N mass to 30 cm depth increased in all systems during 1980 2005, but increases were smaller in CG (0.59 Mg N ha-1) than in AER (1.90 Mg N ha-1) and CF (1.63 Mg N ha-1), showing the effect of legumes, perennial species, and manure in the latter systems. The proportion of total N inputs retained as soil N with organic N inputs in AER (44%) was about twice that with synthetic N fertilizer in CG (23%). The CF system had the lowest productivity and the least N loss to the environment (4 kg N ha-1 yr-1, compared to 28 for AER and 24 for CG). The proportion of N inputs lost to the environment was 16% for AER and 24% for CG. In CF, gains of soil N exceeded apparent net N inputs, perhaps because we under-estimated N inputs from clover. Estimate of legume N input was one of the larger sources of uncertainty. The study affirmed the value of N budgets in evaluating agroecosystem performance, and identified AER and CF as productive and sustainable systems due to their minimal reliance on external N inputs and small

  5. Population fragmentation and inter-ecosystem movements of grizzly bears in Western Canada and the Northern United States (United States)

    Proctor, M.F.; Paetkau, David; McLellan, B.N.; Stenhouse, G.B.; Kendall, K.C.; Mace, R.D.; Kasworm, W.F.; Servheen, C.; Lausen, C.L.; Gibeau, M.L.; Wakkinen, W.L.; Haroldson, M.A.; Mowat, G.; Apps, C.D.; Ciarniello, L.M.; Barclay, R.M.R.; Boyce, M.S.; Schwartz, C.C.; Strobeck, C.


    Population fragmentation compromises population viability, reduces a species ability to respond to climate change, and ultimately may reduce biodiversity. We studied the current state and potential causes of fragmentation in grizzly bears over approximately 1,000,000 km 2 of western Canada, the northern United States (US), and southeast Alaska. We compiled much of our data from projects undertaken with a variety of research objectives including population estimation and trend, landscape fragmentation, habitat selection, vital rates, and response to human development. Our primary analytical techniques stemmed from genetic analysis of 3,134 bears, supplemented with radiotelemetry data from 792 bears. We used 15 locus microsatellite data coupled withmeasures of genetic distance, isolation-by-distance (IBD) analysis, analysis of covariance (ANCOVA), linear multiple regression, multi-factorial correspondence analysis (to identify population divisions or fractures with no a priori assumption of group membership), and population-assignment methods to detect individual migrants between immediately adjacent areas. These data corroborated observations of inter-area movements from our telemetry database. In northern areas, we found a spatial genetic pattern of IBD, although there was evidence of natural fragmentation from the rugged heavily glaciated coast mountains of British Columbia (BC) and the Yukon. These results contrasted with the spatial pattern of fragmentation in more southern parts of their distribution. Near the Canada-US border area, we found extensive fragmentation that corresponded to settled mountain valleys andmajor highways. Genetic distances across developed valleys were elevated relative to those across undeveloped valleys in central and northern BC. In disturbed areas, most inter-area movements detected were made by male bears, with few female migrants identified. North-south movements within mountain ranges (Mts) and across BC Highway 3 were more common

  6. Tepees in peritidal carbonates: origin via earthquake-induced deformation, with example from the Middle Cambrian of western Canada (United States)

    Pratt, Brian R.


    Tepee structures are common in many ancient carbonate tidal flat successions, and because analogues are known from tropical coastal areas, they are well established as evidence for synsedimentary lithification of subaerially exposed carbonate sediment. Existing explanations involving desiccation, thermal expansion and contraction, fluctuating groundwater pore pressure or diagenetic force of crystallization do not adequately account for the style and degree of deformation seen in some examples, such as those in the Middle Cambrian Cathedral Formation of the southern Rocky Mountains, western Canada. These tepees provide evidence for essentially instantaneous events causing brittle failure of decimetre-thick crusts of ooidal and pisoidal grainstone, followed by their dilation, rupturing, separation, tilting and shingling. They can be explained as breccias generated by sporadic episodes of strong ground motion from earthquakes that emanated from a syndepositionally active fault system nearby. Variably directed tensile and compressive stresses broke crusts, shifted them upwards and shuffled them laterally. Subsequent microbial encrustation and vigorous flushing by seawater in the resulting shelter cavities led to rapid stabilization by cementation. Recognition of the role of seismically induced deformation in explaining some tepee structures furnishes a proxy for synsedimentary tectonism and adds another member to the family of 'seismites' which reflect a range of rheological properties of unlithified and lithifying sediments.

  7. Life cycle analysis of multi-crop lignocellulosic material (perennial grasses) for bioethanol production in western Canada : a review.

    Energy Technology Data Exchange (ETDEWEB)

    Tripathy, A. [Saskatchewan Univ., Saskatoon, SK (Canada). Dept. of Agricultural and Bioresource Engineering; Agriculture and Agri-Food Canada, Saskatoon Research Centre, Saskatoon, SK (Canada). Bioproducts and Bioprocessing; Panigrahi, S. [Saskatchewan Univ., Saskatoon, SK (Canada). Dept. of Agricultural and Bioresource Engineering; Mupondwa, E.K. [Agriculture and Agri-Food Canada, Saskatoon Research Centre, Saskatoon, SK (Canada). Bioproducts and Bioprocessing


    This paper presented a life cycle assessment of multi-crop lignocellulosic biomass to determine the environmental performance of a bioethanol biorefinery in western Canada. The study investigated the economic aspects of the ethanol fuel system such as biorefinery operating costs and possible improvements in biorefinery economics resulting from pretreatment, hydrolysis, and fermentation processes. The eco-efficiency was determined by comparing economic parameters with selected environmental parameters. The study also compared the efficiency of the lignoce lulosic biorefinery with grain-based dry milling ethanol plants that produce ethanol as well as dried grains and solubles used as animal feed. The study showed that the choice of feedstock and location of the biorefinery is very important. The location should be carefully chosen where there is no water shortage. Various low valued lignocellulosic energy crops such as switch grass, alfalfa, and other perennial grasses can grow in marginal or pasture land and can decrease production costs considerably, thus improving the economic viability of biorefineries. The use of co-products can also add value to the process and can decrease the cost of ethanol production. tabs., figs.

  8. Half-century evidence from western Canada shows forest dynamics are primarily driven by competition followed by climate. (United States)

    Zhang, Jian; Huang, Shongming; He, Fangliang


    Tree mortality, growth, and recruitment are essential components of forest dynamics and resiliency, for which there is great concern as climate change progresses at high latitudes. Tree mortality has been observed to increase over the past decades in many regions, but the causes of this increase are not well understood, and we know even less about long-term changes in growth and recruitment rates. Using a dataset of long-term (1958-2009) observations on 1,680 permanent sample plots from undisturbed natural forests in western Canada, we found that tree demographic rates have changed markedly over the last five decades. We observed a widespread, significant increase in tree mortality, a significant decrease in tree growth, and a similar but weaker trend of decreasing recruitment. However, these changes varied widely across tree size, forest age, ecozones, and species. We found that competition was the primary factor causing the long-term changes in tree mortality, growth, and recruitment. Regional climate had a weaker yet still significant effect on tree mortality, but little effect on tree growth and recruitment. This finding suggests that internal community-level processes-more so than external climatic factors-are driving forest dynamics.

  9. Transient peat properties in two pond-peatland complexes in the sub-humid Western Boreal Plain, Canada

    Directory of Open Access Journals (Sweden)

    R.M. Petrone


    Full Text Available In the Canadian Western Boreal Plain (WBP, wetlands (ponds and peatlands comprise up to 50% of the landscape and represent unique habitat where summer precipitation is often outpaced by evapotranspiration and hillslope groundwater position does not follow topography. In this sub-humid location, groundwater fluxes and stores in riparian peatlands influence pond water levels and root zone moisture sources for forested uplands. To accurately describe the transport and retention of water in peat, it is important to consider peat subsidence. This paper quantifies the amount and effect of seasonal subsidence in a riparian peatland in the Utikuma Lake region in north-central Alberta, Canada. Results demonstrate that the deep and poorly decomposed peat deposits are resistant to compression, and that thick (and persistent ground frost hinders pore collapse (shrinkage above the water table until late summer when the ground has thawed. Even then, subsidence is still limited to the top 50 cm and is not closely related to changes in peatland water table or pond water level. Thus the water balance of these ponds and riparian areas appears to be less sensitive to peat volume changes than it is to the persistence of a substantial frost layer well into the snow-free period.

  10. Western Canada study of animal health effects associated with exposure to emissions from oil and gas field facilities : technical summary

    Energy Technology Data Exchange (ETDEWEB)



    The impact of exposure to emissions from oil and gas field facilities on animal and human health has been a long-standing concern in western Canada. This technical summary presented highlights of the 17 major research appendices of a study examining associations between emissions and important reproductive parameters in beef cattle, including pregnancy rates, frequencies of abortions and stillbirths, and the risk of death among young calves. The effect of exposure to emissions on the respiratory, immune and nervous systems of calves and yearlings was also evaluated. The study was an epidemiological investigation that drew on large blocks of data collected from privately owned cow-calf operations, laboratory analyses of biological samples and samplers from air monitors. Mixed effect regression models were used to investigate whether measures of reproductive, immunological, and pathology outcomes were associated with emissions from the petroleum industry. Appropriate statistical adjustments were made to correct for multiple comparisons following standard statistical practice. An overview of the methods used to analyze the data was presented, as well as an examination of the methods of epidemiology in determining a causal effect, and the limitations of a single study in determining causation with certainty. Information on water quality testing and feeding management and forage testing was provided. 15 tabs., 26 figs.

  11. Cow attributes, herd management, and reproductive history events associated with abortion in cow-calf herds from Western Canada. (United States)

    Waldner, C L


    The primary objective of this study was to identify herd management and cow characteristics that are associated with abortion in cow-calf herds in Western Canada. Reproductive events were closely monitored in 29,713 cows in 203 herds from the beginning of the breeding season in 2001 through the calving season in 2002. Herd management and cow-level risk factors such as age, body condition score, and previous reproductive history were measured through a series of herd visits by project personnel and detailed individual animal records maintained by the herd owner. Pregnancy status was assessed in fall of 2001 by the herd veterinarian. Cows most likely to abort were replacement heifers, cows that were more than 10 years of age, cows with a body condition score of less than or equal to or 5 of 9 at pregnancy testing, or with twin pregnancies. Cows vaccinated for bovine viral diarrhea virus and infectious bovine rhinotracheitis and bred on community pastures were less likely to abort than cows from community pastures that were not vaccinated. Cows bred on community pastures that were not vaccinated were also more likely to abort than cows that were not on community pastures regardless of vaccination status. Adverse calving-associated events such as severe dystocia, problems such as uterine prolapse or retained placentas, abortion or calf death within 1 hour of birth were also associated with an increased risk of abortion the subsequent calving season after accounting for all other factors.

  12. Trends in the seasonal length and opening dates of a winter road in the western James Bay region, Ontario, Canada (United States)

    Hori, Yukari; Gough, William A.; Butler, Ken; Tsuji, Leonard J. S.


    In northern Canada, winter roads are essential for communities. The duration of the winter road season depends on particular meteorological conditions. In this study, we investigated whether there is a temporal relationship between seasonal weather trends and the historical opening dates of the James Bay Winter Road in Ontario's Far North. The statistical significance of the temporal trends and their magnitude are determined by the Mann-Kendall test and the Theil-Sen method. Results showed that decreasing trends in the freezing degree-days (FDDs) are statistically significant, along with the statistically significant increasing trends of monthly averages of both T min and T mean during the winter months in the western James Bay region for the 1961-2014 period. However, there were no statistically significant linkages between opening dates and FDDs detected, perhaps due to the paucity of opening dates data, although early opening dates in the last 10 years may be the result of larger FDDs. The FDDs during the months of October through December were more closely linked to opening dates than FDDs that were calculated up the opening date (including January dates), suggesting the key role of preconditioning during late fall and early winter. The lowest FDDs for the months of October to December that resulted in a viable winter road were 380 degree-days (°C). This threshold can be potentially used as a lower threshold for winter roads.

  13. Trends in the seasonal length and opening dates of a winter road in the western James Bay region, Ontario, Canada (United States)

    Hori, Yukari; Gough, William A.; Butler, Ken; Tsuji, Leonard J. S.


    In northern Canada, winter roads are essential for communities. The duration of the winter road season depends on particular meteorological conditions. In this study, we investigated whether there is a temporal relationship between seasonal weather trends and the historical opening dates of the James Bay Winter Road in Ontario's Far North. The statistical significance of the temporal trends and their magnitude are determined by the Mann-Kendall test and the Theil-Sen method. Results showed that decreasing trends in the freezing degree-days (FDDs) are statistically significant, along with the statistically significant increasing trends of monthly averages of both T min and T mean during the winter months in the western James Bay region for the 1961-2014 period. However, there were no statistically significant linkages between opening dates and FDDs detected, perhaps due to the paucity of opening dates data, although early opening dates in the last 10 years may be the result of larger FDDs. The FDDs during the months of October through December were more closely linked to opening dates than FDDs that were calculated up the opening date (including January dates), suggesting the key role of preconditioning during late fall and early winter. The lowest FDDs for the months of October to December that resulted in a viable winter road were 380 degree-days (°C). This threshold can be potentially used as a lower threshold for winter roads.

  14. Deformed wing virus in western honey bees (Apis mellifera) from Atlantic Canada and the first description of an overtly-infected emerging queen. (United States)

    Williams, Geoffrey R; Rogers, Richard E L; Kalkstein, Abby L; Taylor, Benjamin A; Shutler, Dave; Ostiguy, Nancy


    Deformed wing virus (DWV) in western honey bees (Apis mellifera) often remains asymptomatic in workers and drones, and symptoms have never been described from queens. However, intense infections linked to parasitism by the mite Varroa destructor can cause worker wing deformity and death within 67 h of emergence. Ten workers (eight with deformed wings and two with normal wings) and three drones (two with deformed wings and one with normal wings) from two colonies infected with V. destructor from Nova Scotia, Canada, and two newly-emerged queens (one with deformed wings and one with normal wings) from two colonies infected with V. destructor from Prince Edward Island, Canada, were genetically analyzed for DWV. We detected DWV in all workers and drones, regardless of wing morphology, but only in the deformed-winged queen. This is the first report of DWV from Atlantic Canada and the first detection of a symptomatic queen with DWV from anywhere.

  15. The Cora Lake Shear Zone, an Exhumed Deep Crustal Lithotectonic Discontinuity, Western Churchill Province, Canada (United States)

    Regan, S.; Leslie, S.; Holland, M. E.; Williams, M. L.; Mahan, K. H.; Jercinovic, M. J.


    Deep crustal flow is a fundamental tectonic process that may serve to reduce topographic gradients, especially in overthickened collisional orogens. Recent studies have utilized numerical models and seismic interpretations, but generally in two dimensions. Although useful, two dimensional models can not fully characterize lower crustal flow or coupling of crustal layers because they cannot fully incorporate lateral heterogeneity in the flow field. The Athabasca Granulite terrane, in northern Saskatchewan, is an exposed deep crustal terrane that underwent granulite grade deformation during the Neoarchean (ca. 2.55), then cooled isobarically for 600 m.y., and then was reactivated during the Paleoproterozoic (ca. 1.9 Ga). Regional exhumation occurred at roughly 1.85 Ga. This exposure, is a field laboratory for studying lower crustal flow, stabilization, and reactivation. Recent work suggests that the northwestern domain, dominated by the multiphase, opx-bearing, Mary batholith, underwent top-to-the-east lower crustal flow during the Neoarchean. The Chipman domain, to the SE , is primarily underlain by the 3.2 Ga, Chipman tonalite straight gneiss, which was likely restitic, and rheologically strong during the 2.6 Ga flow event. The Cora Lake shear zone (CLsz), which divides the two domains, is interpreted to represent a lithotectonic, compositional, and rheologic boundary within the deep crust. Recent mapping of the western gradient of the CLsz has provided insight into the role and evolution of the rheologic discontinuity and its relationship to crustal flow. The Mary granite (gneiss) contains excellent assemblages for P-T and pseudosection analysis. Interlayered felsic granulite contain abundant monazite for in-situ geochronology. An intense subhorizontal tectonic fabric (S1), interpreted to be the product of crustal flow, is present in both units. This early fabric was locally crenulated, folded, and transposed, by a sub-vertical S2 fabric. Current work involves

  16. Controlled Release Urea as a Nitrogen Source for Spring Wheat in Western Canada: Yield, Grain N Content, and N Use Efficiency


    Lenz Haderlein; T.L. Jensen; Dowbenko, R.E.; A.D. Blaylock


    Controlled release nitrogen (N) fertilizers have been commonly used in horticultural applications such as turf grasses and container-grown woody perennials. Agrium, a major N manufacturer in North and South America, is developing a low-cost controlled release urea (CRU) product for use in field crops such as grain corn, canola, wheat, and other small grain cereals. From 1998 to 2000, 11 field trials were conducted across western Canada to determine if seed-placed CRU could maintain crop yield...

  17. Controlled Release Urea as a Nitrogen Source for Spring Wheat in Western Canada: Yield, Grain N Content, and N Use Efficiency


    Lenz Haderlein; Jensen, T. L.; Dowbenko, R.E.; A.D. Blaylock


    Controlled release nitrogen (N) fertilizers have been commonly used in horticultural applications such as turf grasses and container-grown woody perennials. Agrium, a major N manufacturer in North and South America, is developing a low-cost controlled release urea (CRU) product for use in field crops such as grain corn, canola, wheat, and other small grain cereals. From 1998 to 2000, 11 field trials were conducted across western Canada to determine if seed-placed CRU could maintain crop yield...

  18. Miocene Antarctic ice dynamics in the Ross Embayment (Western Ross Sea, Antarctica): Insights from provenance analyses of sedimentary clasts in the AND-2A drill core (United States)

    Cornamusini, Gianluca; Talarico, Franco M.


    A detailed study of gravel-size sedimentary clasts in the ANDRILL-2A (AND-2A) drill core reveals distinct changes in provenance and allows reconstructions to be produced of the paleo ice flow in the McMurdo Sound region (Ross Sea) from the Early Miocene to the Holocene. The sedimentary clasts in AND-2A are divided into seven distinct petrofacies. A comparison of these with potential source rocks from the Transantarctic Mountains and the coastal Southern Victoria Land suggests that the majority of the sedimentary clasts were derived from formations within the Devonian-Triassic Beacon Supergroup. The siliciclastic-carbonate petrofacies are similar to the fossiliferous erratics found in the Quaternary Moraine in the southern McMurdo Sound and were probably sourced from Eocene strata that are currently hidden beneath the Ross Ice Shelf. Intraformational clasts were almost certainly reworked from diamictite and mudstone sequences that were originally deposited proximal to the drill site. The distribution of sedimentary gravel clasts in AND-2A suggests that sedimentary sequences in the drill core were deposited under two main glacial scenarios: 1) a highly dynamic ice sheet that did not extend beyond the coastal margin and produced abundant debris-rich icebergs from outlet glaciers in the central Transantarctic Mountains and South Victoria Land; 2) and an ice sheet that extended well beyond the coastal margin and periodically advanced across the Ross Embayment. Glacial scenario 1 dominated the early to mid-Miocene (between ca. 1000 and 225 mbsf in AND-2A) and scenario 2 the early Miocene (between ca. 1138 and 1000 mbsf) and late Neogene to Holocene (above ca. 225 mbsf). This study augments previous research on the clast provenance and highlights the added value that sedimentary clasts offer in terms of reconstructing past glacial conditions from Antarctic drill core records.

  19. Hydraulic properties and scale effects investigation in regional rock aquifers, south-western Quebec, Canada (United States)

    Nastev, M.; Savard, M. M.; Lapcevic, P.; Lefebvre, R.; Martel, R.

    This paper reports on the characterization of hydraulic properties of regional rock aquifers carried out within a groundwater resources assessment project in the St. Lawrence Lowlands of south-western Quebec. To understand the aquifer behavior at both the fracture level and at field scale, hydraulic investigations were carried out using various aquifer tests. The groundwater flow at the local scale is controlled mostly by the fracture system. Results of the constant-head injection tests show a weak decreasing trend of hydraulic conductivity with depth indicating that a major part of the groundwater flow occurs in the first meters of the rock sequence. At the regional scale, the equivalent porous media approach is applicable. The hydraulic conductivity measurements were correlated to the scale of the aquifer tests expressed with the investigated aquifer volume. A simple interpolation procedure for the hydraulic conductivity field was developed based on the distance between field measurements and the tested aquifer volumes. The regional distribution of the hydraulic conductivity for the major fractured aquifer units indicates that dolostone is the most permeable whereas sandstone and crystalline rocks are the least permeable units. Este artículo trata de la caracterización de las propiedades hidráulicas en acuíferos regionales rocosos, la cual se llevó a cabo dentro del proyecto de evaluación de los recursos de agua subterránea en St. Lawrence Lowlands al suroeste de Quebec. Para entender el comportamiento del acuífero tanto a nivel de fractura como a escala del campo, se ejecutaron investigaciones hidráulicas usando varias pruebas de acuífero. El flujo del agua subterránea a escala local está controlado principalmente por el sistema de fracturas. Los resultados de las pruebas de inyección con cabeza constante muestran una tendencia decreciente débil de la conductividad hidráulica con la profundidad, indicando que la mayor parte del flujo de agua

  20. Sedimentary input of trace metals from the Chukchi Shelf (United States)

    Aguilar-Islas, A. M.; Seguré, M.; Rember, R.; Nishino, S.


    The distribution of trace metals in the Arctic Ocean has implications for their global cycles, yet until recently few trace metal observations were available from this rapidly changing ocean. Profiles of dissolved Fe from recent Japanese field efforts in the Western Canada Basin (2008, 2010) indicate the broad Chukchi Shelf as a source of Fe to the halocline of the Western Canada Basin. Here we present dissolved and particulate data for crustal (Al, Mn, Fe) and non-crustal elements (Co, Cu, Zn) from the productive Chukchi Sea to characterize the sedimentary input of these metals to shelf waters contributing to the halocline layer of the Canada Basin. Water column profiles were collected in late summer 2013 onboard the R/V Mirai at 10 stations from the Bering Strait to the slope, and at a time-series (10 days) station located over the outer shelf. A narrow and variable (5-10 m) benthic boundary layer was sampled at the time-series station with highly elevated dissolved and suspended particulate metal concentrations. High metal concentrations were also observed in the subsurface at a station over Barrow Canyon where mixing is enhanced. Reactivity of suspended particulate metals was determined by the leachable vs. refractory fractions. Metal concentrations were determined by ICP-MS. Trace metal transport from the shelf to the interior will be discussed in context with shelf mechanisms contributing to this export, and to expected future changes in the Arctic Ocean.

  1. Potential rates of anaerobic decomposition and experimental priming effects in thawed peats from discontinuous permafrost in western Canada (United States)

    Estop Aragones, C.; Heffernan, L.; Olefeldt, D.


    Recent climate change has led to increased rates of warming and wildfire in the circumpolar region. It is predicted that this will promote the widespread thawing of permafrost and the development of thermokarst bogs in the peatlands of western Canada. Previously frozen deep organic matter becomes available to microbial activity with thermokarst with the potential loss of C stocks while liberating greenhouse gases to the atmosphere and creating a positive feedback to climate change. Although anoxic conditions in these waterlogged systems may reduce peat decomposition, fresh plant derived C inputs associated with high vegetation productivity post-thaw could increase peat decomposition. The effect of this potential mechanism on enhanced peat decomposition is poorly investigated though. We are measuring anaerobic CO2 and CH4 production rates from a peat plateau, an adjacent young and an old thermokarst feature in the discontinuous permafrost. Samples were selected from depths where peat has been exposed to seasonal thaw (active layer) and from deeper, previously frozen organic matter along 5 m profiles. Preliminary results indicate that most CO2 production is driven by the top meter of peat, especially in the recent thermokarst where the highest rates of CH4 production are also measured due to high vegetation productivity post-thaw. Data suggests that the decomposition of deeper peat is more temperature sensitive. We are considering a 13C labelling experiment to investigate the priming effects on heterotrophic respiration of organic matter heterotrophic respiration once the labile C pool has been depleted and production rates have become stable over time. Fourier transform infrared (FTIR) spectroscopy will be used to determine how peat quality is related to anaerobic decomposition rates, its temperature dependency, and priming effects. These measurements aim to constrain the fate of C through anaerobic decomposition upon permafrost thaw.

  2. Screening for neurocognitive impairment, depression, and anxiety in HIV-infected patients in Western Europe and Canada. (United States)

    Robertson, Kevin; Bayon, Carmen; Molina, Jean-Michel; McNamara, Patricia; Resch, Christiane; Muñoz-Moreno, Jose A; Kulasegaram, Ranjababu; Schewe, Knud; Burgos-Ramirez, Angel; De Alvaro, Cristina; Cabrero, Esther; Guion, Matthew; Norton, Michael; van Wyk, Jean


    CRANIum, a cross-sectional epidemiology study in Western Europe and Canada, was conducted to describe and compare the prevalence of a positive screen for neurocognitive impairment (NCI), depressive symptoms, and anxiety in an HIV-positive population either receiving combination antiretroviral therapy (cART) or who were naive to antiretroviral therapy (ART). HIV-positive patients ≥18 years of age attending a routine medical follow-up visit and able to complete the designated screening tools were eligible for study inclusion. The Brief Neurocognitive Screen was used to assess NCI; depressive and anxiety symptoms were assessed using the Hospital Anxiety and Depression Scale. The evaluable patient population (N = 2863) included 1766 men (61.7%) and 1096 (38.3%) women. A total of 1969 patients were cART-experienced (68.8%), and 894 were ART-naive (31.2%). A positive screen for NCI was found in 41.5% of patients (cART-experienced, 42.5%; ART-naive, 39.4%; p = 0.12). A positive screen for depressive symptoms was found in 15.7% of patients (cART-experienced, 16.8%; ART-naive, 13.3%; p = 0.01), whereas 33.3% of patients screened positive for anxiety (cART-experienced, 33.5%; ART-naive, 32.8%; p = 0.71). A greater percentage of women compared with men screened positive for NCI (51.78% vs. 35.1%; p < 0.0001) and depressive symptoms (17.9% vs. 14.3%; p = 0.01). These data suggest that neurocognitive and mood disorders remain highly prevalent in HIV-infected patients. Regular mental health screening in this population is warranted.

  3. Spatial genetic structure of the mountain pine beetle (Dendroctonus ponderosae) outbreak in western Canada: historical patterns and contemporary dispersal. (United States)

    Gayathri Samarasekera, G D N; Bartell, Nicholas V; Lindgren, B Staffan; Cooke, Janice E K; Davis, Corey S; James, Patrick M A; Coltman, David W; Mock, Karen E; Murray, Brent W


    Environmental change has a wide range of ecological consequences, including species extinction and range expansion. Many studies have shown that insect species respond rapidly to climatic change. A mountain pine beetle epidemic of record size in North America has led to unprecedented mortality of lodgepole pine, and a significant range expansion to the northeast of its historic range. Our goal was to determine the spatial genetic variation found among outbreak population from which genetic structure, and dispersal patterns may be inferred. Beetles from 49 sampling locations throughout the outbreak area in western Canada were analysed at 13 microsatellite loci. We found significant north-south population structure as evidenced by: (i) Bayesian-based analyses, (ii) north-south genetic relationships and diversity gradients; and (iii) a lack of isolation-by-distance in the northernmost cluster. The north-south structure is proposed to have arisen from the processes of postglacial colonization as well as recent climate-driven changes in population dynamics. Our data support the hypothesis of multiple sources of origin for the outbreak and point to the need for population specific information to improve our understanding and management of outbreaks. The recent range expansion across the Rocky Mountains into the jack/lodgepole hybrid and pure jack pine zones of northern Alberta is consistent with a northern British Columbia origin. We detected no loss of genetic variability in these populations, indicating that the evolutionary potential of mountain pine beetle to adapt has not been reduced by founder events. This study illustrates a rapid range-wide response to the removal of climatic constraints, and the potential for range expansion of a regional population. © 2012 Blackwell Publishing Ltd.

  4. Energy Efficiency as a Preferred Resource: Evidence from Utility Resource Plans in the Western United States and Canada

    Energy Technology Data Exchange (ETDEWEB)

    Hopper, Nichole; Barbose, Galen; Goldman, Charles; Schlegel, Jeff


    This article examines the future role of energy efficiency as a resource in the Western United States and Canada, as envisioned in the most recent resource plans issued by 16 utilities, representing about 60percent of the region's load. Utility and third-party administered energy efficiency programs proposed by 15 utilities over a ten-year horizon would save almost 19,000 GWh annually, about 5.2percent of forecast load. There are clear regional trends in the aggressiveness of proposed energy savings. California's investor-owned utilities (IOUs) had the most aggressive savings targets, followed by IOUs in the Pacific Northwest, and the lowest savings were proposed by utilities in Inland West states and by two public utilities on the West coast. The adoption of multiple, aggressive policies targeting energy efficiency and climate change appear to produce sizeable energy efficiency commitments. Certain specific policies, such as mandated energy savings goals for California's IOUs and energy efficiency provisions in Nevada's Renewable Portfolio Standard had a direct impact on the level of energy savings included in the resource plans. Other policies, such as revenue decoupling and shareholder incentives, and voluntary or legislatively mandated greenhouse gas emission reduction policies, may have also impacted utilities' energy efficiency commitments, though the effects of these policies are not easily measured. Despite progress among the utilities in our sample, more aggressive energy efficiency strategies that include high-efficiency standards for additional appliances and equipment, tighter building codes for new construction and renovation, as well as more comprehensive ratepayer-funded energy efficiency programs are likely to be necessary to achieve a region-wide goal of meeting 20percent of electricity demand with efficiency in 2020.

  5. Sedimentary connection between rock glaciers and torrential channels: definition, inventory and quantification from a test area in the south-western Swiss Alps (United States)

    Kummert, Mario; Barboux, Chloé; Delaloye, Reynald


    Permafrsot creep is an important sediment transfer process in periglacial alpine hillslopes (Delaloye et al. 2010). Rock glaciers are the visible expression of mountain permafrost creep (Delaloye 2004). Large volumes of rock debris originating from headwalls, moraines and weathering deposits are slowly transported within rock glaciers from their rooting zone to their fronts. In the Alps, most rock glaciers can be considered as sediment traps, because the sediment output at their margin is usually limited (Gärtner-Roer 2012). However, cases of rock glacier supplying torrential channels with sediments have been documented (e.g. Lugon and Stoffel 2010, Delaloye et al. 2013) Such rock glaciers can act as a sediment source for the triggering of gravitational processes propagating further downstream. Moreover, in such configuration the amount of sediment available is not a finite volume but is gradually renewed or increased as the rock glacier advances. These cases are therefore very specific, especially in the perspective of natural hazards assessment and mitigation. However, in the Alps very little is known about such type of rock glaciers. In addition, the sediment transfer rates between the fronts of the rock glaciers and the torrents are often not known. In this context, our study aims at (i) defining better the configurations in which a sedimentary connection exists between rock glaciers and torrential channels, (ii) localizing the cases of active rock glaciers connected to the torrential network and (iii) estimating approximate sediment transfer rates between the fronts and the torrential gullies. For that purpose, an inventory method for the classification of torrential catchments based on the analysis of aerial images and the computation of connectivity indexes have been developped. In addition, sediment transfer rates were estimated taking into account the geometry of the frontal areas and the velocity rates of the rock glaciers derived from DInSAR data. In

  6. Mineralogical and geochemical characteristics of Miocene pelitic sedimentary rocks from the south-western part of the Pannonian Basin System (Croatia: Implications for provenance studies

    Directory of Open Access Journals (Sweden)

    Anita Grizelj


    Full Text Available Fifty-two samples of Miocene pelitic sedimentary rock from outcrops on Medvednica, Moslavačka Gora and Psunj Mts., and boreholes in the Sava Depression and the Požega Sub-depression were investigated. These sediments formed in different marine (with normal and reduced salinity, brackish, and freshwater environments, depending on the development stage of the Pannonian Basin System. Carbonate minerals, clay minerals and quartz are the main constituents of all pelitic sedimentary rocks, except in those from Moslavačka Gora Mt in which carbonate minerals are not present. Feldspars, pyrite, opal-CT, and hematite are present as minor constituents in some rocks. Besides calcite, dependent on the sedimentary environment and diagenetic changes, high-magnesium calcite, aragonite, dolomite and ankerite/Ca-dolomite are also present. Smectite or illite-smectite is the main clay minerals in the samples. Minor constituents, present in almost all samples, are detrital illite and kaolinite. In some samples chlorite is also present in a low amount. Major elements, trace elements and rare earth elements patterns used in provenance analysis show that all analysed samples have a composition similar to the values of the upper continental crust (UCC. The contents of major and trace elements as well as SiO2/Al2O3, K2O/Al2O3, Na2O/K2O, Eu/Eu*, La/Sc, Th/Sc, La/Co Th/Co, Th/Cr, Ce/Ce* and LREE/HREE ratios, show that the analysed pelitic sedimentary rocks were formed by weathering of different types of mostly acidic (silicic, i.e. felsic rocks.

  7. Relative performance of different exposure modeling approaches for sulfur dioxide concentrations in the air in rural western Canada

    Directory of Open Access Journals (Sweden)

    Kim Hyang-Mi


    Full Text Available Abstract Background The main objective of this paper is to compare different methods for predicting the levels of SO2 air pollution in oil and gas producing area of rural western Canada. Month-long average air quality measurements were collected over a two-year period (2001–2002 at multiple locations, with some side-by-side measurements, and repeated time-series at selected locations. Methods We explored how accurately location-specific mean concentrations of SO2 can be predicted for 2002 at 666 locations with multiple measurements. Means of repeated measurements on the 666 locations in 2002 were used as the alloyed gold standard (AGS. First, we considered two approaches: one that uses one measurement from each location of interest; and the other that uses context data on proximity of monitoring sites to putative sources of emission in 2002. Second, we imagined that all of the previous year's (2001's data were also available to exposure assessors: 9,464 measurements and their context (month, proximity to sources. Exposure prediction approaches we explored with the 2001 data included regression modeling using either mixed or fixed effects models. Third, we used Bayesian methods to combine single measurements from locations in 2002 (not used to calculate AGS with different priors. Results The regression method that included both fixed and random effects for prediction (Best Linear Unbiased Predictor had the best agreement with the AGS (Pearson correlation 0.77 and the smallest mean squared error (MSE: 0.03. The second best method in terms of correlation with AGS (0.74 and MSE (0.09 was the Bayesian method that uses normal mixture prior derived from predictions of the 2001 mixed effects applied in the 2002 context. Conclusion It is likely that either collecting some measurements from the desired locations and time periods or predictions of a reasonable empirical mixed effects model perhaps is sufficient in most epidemiological applications. The

  8. Geological and production characteristics of the Lewis Shale, San Juan Basin, USA: an ongoing study with applications to other foreland basins of the Western Interior, USA and Canada

    Energy Technology Data Exchange (ETDEWEB)

    Bereskin, R. [Tesseract Corporation, Park City, UT (United States)


    The geological characteristics of the Lewis Shale, San Juan Basin, New Mexico is examined to provide information about ways to characterize productive wells. Logs of Cretaceous shale need to be examined more closely. The lithology, environment of deposition, and porosity types shown by a type log of Lewis shale and the utility of a FMI log for indicating various features are described. Integrated use of core, FMI, gamma ray, and neutron log techniques improve target identification. Lewis shale analogues likely exist along lengths of the Western Interior and Canada. 21 figs.

  9. Geochemistry of metamorphosed basaltic and sedimentary rocks from the Smolník Cu-pyrite deposit (Gemeric Superunit, Western Carpathians: a reappraisal of older geochemical data

    Directory of Open Access Journals (Sweden)

    Peter Ivan


    Full Text Available Stratiform chalcopyrite-pyrite deposit of Smolník is located in the low-grade metamorphosed Early Palaeozoic volcano-sedimentary Gelnica Group. Various types of phyllites, mostly sericite and graphite-sericite phyllites with metadolerite bodies build up proximate vicinity of the deposit. The imminent host rocks of sulphide pods are chlorite phyllites with subordinate chlorite-sericite phyllites intercallations. Metadolerites previously interpreted as effusive rocks are probably subvolcanic in origin. Original igneous mineral association of clinopyroxene, plagioclase, ilmenite and probably also olivine were transformed to association of amphiboles, albite, clinozoisite/epidote, titanite ± calcite by metamorphic alteration. Composition of metadolerites is close to basaltic liquids although indices of some fractionation of plagioclase, olivine/chromspinelide or clinopyroxene exist. Trace element distribution points to their similarity to within-plate continental tholeiites (CT and probable relation to the beginning of rifting in the Lower Devonian time. Three possible sources of sedimentary material have been identified in the sedimentary host rocks of the Smolník deposit: (i basalts generated from enriched mantle reservoir; (ii less fractionated calc-alkaline volcanic rocks and (iii fractionated calc-alkaline rhyolites. An additional hydrothermal source for silica and iron is supposed for chlorite phyllites and allows classified them as metaexhalites. The sulphide ores were directly precipitated in the exhalite environment due to reaction hydrothermal solution with hydrogen sulphide produced by thermochemical reduction of the marine sulphate. Geochemical data on metamorphosed dolerites and sediments in combination to other geological characteristics of the Smolník deposit support its classification as the Besshi-type deposit.

  10. 豫西鲁山汝阳群微生物成因构造宏观特征分析及其环境演化%Macro-analysis on the Microbially Induced Sedimentary Structures Features and the Sedimentary Environmental Evolution in the Ruyang Group of Lushan,Western Henan

    Institute of Scientific and Technical Information of China (English)

    郑伟; 孙凤余


    豫西鲁山地区汝阳群发育了大量形态特征多样的微生物成因构造(microbially induced sedimentary struc-tures),简称MISS,是微生物席或微生物膜与其他物理作用营力(如剥蚀作用、沉积作用、搬运作用和变形作用)相互作用的产物,也可被视为一种广义的遗迹化石,其最主要的两种类型是多边形网格状脱水裂痕和纺锤形脱水裂痕。笔者通过对地层中发育的微生物成因构造宏观特征的描述和统计分析,探讨了MISS与沉积环境之间的关系,认为微生物成因构造的总体特征演化规律与汝阳群趋于稳定的沉积环境演化规律一致,其形态特征与微生物席厚、暴露时间频繁与否有着密切的关系。%Abundant Microbially Induced Sedimentary Structures(MISS) were preserved in the Ruyang Group of Lushan,Western Henan Province.They formed by the combining action of the microbial mat(or microbial film) with some kinds of physical actions such as denudation,sedimentation,transportation and deformation.To some extent,they can be regarded as trace fossils.Mesh-like and fusiform syneresis cracks are dominant.Based on the description and the macro-analysis on the MISS features,the authors discuss the relation between MISS and sedimentary environment,it is considered that the evolution of the MISS is consistent with the sedimentary environments.The morphological features of the MISS have a close relation to the thickness of microbial mat and their frequent exposure.

  11. Luminescence- and Infrared-Radiofluorescence dating of the Acheulean- to Middle Stone Age sedimentary sequence at Montagu Cave, Western Cape Provence, South Africa (United States)

    Lauer, Tobias; Archer, Will; Sumner, Alexandra


    Montagu Cave is an archaeological site located on the edge of the Langeberg mountain range, about 160 km NE of Cape Town, in South Africa. The archaeological and sedimentary units at Montagu Cave comprise two Acheulean sequences which are separated from one another by a substantial archaeological hiatus. There is an additional Middle Stone Age sequence which overlies the Acheulean horizons, and contains layers attributed to the Howiesons Poort, as well as multiple other Middle Stone Age sub-stages. Hence, Montagu Cave provides a unique opportunity to investigate quite complex population level questions concerning the behavioral differences between modern and pre-modern populations in southern Africa. However, thus far, the chronological context of the sediment-layers at the site remains unclear. It is therefore critical to provide a resilient chronological framework for the timing of human activity at the site. This study concerns the potential of luminescence dating for the sedimentary sequence preserved at Montagu cave. The collected samples are tested on their quartz- and feldspar luminescence signal properties. Various optical dating techniques (quartz OSL; pIRIR290) will be applied, and the results of each compared in order to obtain information on the suitability of the material for luminescence dating, and to establish a chronological framework for this important archaeological site. Furthermore, the infrared-radiofluorescence (IR-RF) signal behavior will be tested on potassium feldspars, as IR-RF is a method being able to date back up to > 600 ka. IR-RF therefore has the potential to cover the expected time-frame of the sediments at Montagu-cave.

  12. Neoproterozoic diamictite-bearing sedimentary rocks in the northern Yili Block and their constraints on the Precambrian evolution of microcontinents in the Western Central Asian Orogenic Belt (United States)

    He, Jingwen; Zhu, Wenbin; Zheng, Bihai; Wu, Hailin; Cui, Xiang; Lu, Yuanzhi


    The origin and tectonic setting of Precambrian sequences in the Central Asian Orogenic Belt (CAOB) have been debated due to a lack of high resolution geochronological data. Answering this question is essential for the understanding of the tectonic framework and Precambrian evolution of the blocks within the CAOB. Here we reported LA-ICP-MS detrital zircon U-Pb ages and in-situ Hf isotopic data for Neoproterozoic sedimentary cover in the northern Yili Block, an important component of the CAOB, in order to provide information on possible provenance and regional tectonic evolution. A total of 271 concordant U-Pb zircon ages from Neoproterozoic sedimentary cover in the northern Yili Block define three major age populations of 1900-1400 Ma, 1300-1150 Ma and 700-580 Ma, which are quite different from cratons and microcontinents involved in the CAOB. Although it is not completely consistent with the local basement ages, an autochthonous provenance interpretation is more suitable. Some zircon grains show significant old Hf model ages (TDMC; 3.9-2.4 Ga) and reveal continental crust as old as Paleoarchean probably existed. Continuous Mesoproterozoic zircon age populations exhibit large variations in the εHf(t) ratios, suggesting the long-time involvement of both reworked ancient crust and juvenile material. Similar Mesoproterozoic evolution pattern is identified in many continental terranes involved in the CAOB that surround the Tarim Craton. Based on our analysis and published research, we postulate that the northern Yili Block, together with Chinese Central Tianshan, Kyrgyz North Tianshan and some other microcontinents surrounding the Tarim Craton, once constituted the continental margin of the Tarim Craton in the Mesoproterozoic, formed by long-lived accretionary processes. Most of the late Neoproterozoic zircons exhibit significant positive εHf(t) ratios, suggesting the addition of juvenile crust. It is consistent with the tectonic event related to the East Africa

  13. Constraints on the history and topography of the Northeastern Sierra Nevada from a Neogene sedimentary basin in the Reno-Verdi area, Western Nevada (United States)

    Trexler, James; Cashman, Patricia; Cosca, Michael


    Neogene (Miocene–Pliocene) sedimentary rocks of the northeastern Sierra Nevada were deposited in small basins that formed in response to volcanic and tectonic activity along the eastern margin of the Sierra. These strata record an early phase (ca. 11–10 Ma) of extension and rapid sedimentation of boulder conglomerates and debrites deposited on alluvial fans, followed by fluvio-lacustrine sedimentation and nearby volcanic arc activity but tectonic quiescence, until ~ 2.6 Ma. The fossil record in these rocks documents a warmer, wetter climate featuring large mammals and lacking the Sierran orographic rain shadow that dominates climate today on the eastern edge of the Sierra. This record of a general lack of paleo-relief across the eastern margin of the Sierra Nevada is consistent with evidence presented elsewhere that there was not a significant topographic barrier between the Pacific Ocean and the interior of the continent east of the Sierra before ~ 2.6 Ma. However, these sediments do not record an integrated drainage system either to the east into the Great Basin like the modern Truckee River, or to the west across the Sierra like the ancestral Feather and Yuba rivers. The Neogene Reno-Verdi basin was one of several, scattered endorheic (i.e., internally drained) basins occupying this part of the Cascade intra-arc and back-arc area.

  14. Analysis of tectonic-controlled fluvial morphology and sedimentary processes of the western Amazon Basin: an approach using satellite images and digital elevation model

    Directory of Open Access Journals (Sweden)

    Clauzionor L. Silva


    Full Text Available An investigation of the tectonic controls of the fluvial morphology and sedimentary processes of an area located southwest of Manaus in the Amazon Basin was conducted using orbital remote sensing data. In this region, low topographic gradients represent a major obstacle for morphotectonic analysis using conventional methods. The use of remote sensing data can contribute significantly to overcome this limitation. In this instance, remote sensing data comprised digital elevation model (DEM acquired by the Shuttle Radar Topographic Mission (SRTM and Landsat Thematic Mapper images. Advanced image processing techniques were employed for enhancing the topographic textures and providing a three-dimensional visualization, hence allowing interpretation of the morphotectonic elements. This led to the recognition of main tectonic compartments and several morphostructural features and landforms related to the neotectonic evolution of this portion of the Amazon Basin. Features such as fault scarps, anomalous drainage patterns, aligned ridges, spurs and valleys, are expressed in the enhanced images as conspicuous lineaments along NE-SW, NW-SE, E-W and N-S directions. These features are associated to the geometry of alternated horst and graben structures, the latter filled by recent sedimentary units. Morphotectonic interpretation using this approach has proven to be efficient and permitted to recognize new tectonic features that were named Asymmetric Ariaú Graben, Rombohedral Manacapuru Basin and Castanho-Mamori Graben.Uma investigação do controle tectônico da morfologia fluvial e dos processos sedimentares de uma área localizada a sudoeste da cidade de Manaus, na Bacia do Amazonas, foi conduzida a partir do uso de dados de sensores remotos orbitais. Nessa região, o baixo gradiente topográfico representa o principal obstáculo para a análise morfotectônica usando métodos convencionais. O uso de dados de sensores remotos pode contribuir

  15. The Eocene-Oligocene sedimentary record in the Chesapeake Bay impact structure: Implications for climate and sea-level changes on the western Atlantic margin (United States)

    Schulte, P.; Wade, B.S.; Kontny, A.; ,


    A multidisciplinary investigation of the Eocene-Oligocene transition in the International Continental Scientific Drilling Program (ICDP)-U.S. Geological Survey (USGS) Eyreville core from the Chesapeake Bay impact basin was conducted in order to document environmental changes and sequence stratigraphic setting. Planktonic foraminifera and calcareous nannofossil biostratigraphy indicate that the Eyreville core includes an expanded upper Eocene (Biozones E15 to E16 and NP19/20 to NP21, respectively) and a condensed Oligocene-Miocene (NP24-NN1) sedimentary sequence. The Eocene-Oligocene contact corresponds to a =3-Ma-long hiatus. Eocene- Oligocene sedimentation is dominated by great diversity and varying amounts of detrital and authigenic minerals. Four sedimentary intervals are identified by lithology and mineral content: (1) A 30-m-thick, smectite- and illite-rich interval directly overlies the Exmore Formation, suggesting long-term reworking of impact debris within the Chesapeake Bay impact structure. (2) Subsequently, an increase in kaolinite content suggests erosion from soils developed during late Eocene warm and humid climate in agreement with data derived from other Atlantic sites. However, the kaolinite increase may also be explained by change to a predominant sediment input from outside the Chesapeake Bay impact structure caused by progradation of more proximal facies belts during the highstand systems tract of the late Eocene sequence E10.Spectral analysis based on gamma-ray and magnetic susceptibility logs suggests infl uence of 1.2 Ma low-amplitude oscillation of the obliquity period during the late Eocene. (3) During the latest Eocene (Biozones NP21 and E16), several lithological contacts (clay to clayey silt) occur concomitant with a prominent change in the mineralogical composition with illite as a major component: This lithological change starts close to the Biozone NP19/20-NP21 boundary and may correspond to sequence boundary E10-E11 as observed in

  16. Assessing potential health risks to fish and humans using mercury concentrations in inland fish from across western Canada and the United States (United States)

    Lepak, Jesse M; Hooten, Mevin B.; Eagles-Smith, Collin A.; Tate, Michael T.; Lutz, Michelle A.; Ackerman, Joshua T.; Willacker, James J.; Jackson, Allyson K.; Evers, David C.; Wiener, James G.; Pritz, Colleen Flanagan; Davis, Jay


    Fish represent high quality protein and nutrient sources, but Hg contamination is ubiquitous in aquatic ecosystems and can pose health risks to fish and their consumers. Potential health risks posed to fish and humans by Hg contamination in fish were assessed in western Canada and the United States. A large compilation of inland fish Hg concentrations was evaluated in terms of potential health risk to the fish themselves, health risk to predatory fish that consume Hg contaminated fish, and to humans that consume Hg contaminated fish. The probability that a fish collected from a given location would exceed a Hg concentration benchmark relevant to a health risk was calculated. These exceedance probabilities and their associated uncertainties were characterized for fish of multiple size classes at multiple health-relevant benchmarks. The approach was novel and allowed for the assessment of the potential for deleterious health effects in fish and humans associated with Hg contamination in fish across this broad study area. Exceedance probabilities were relatively common at low Hg concentration benchmarks, particularly for fish in larger size classes. Specifically, median exceedances for the largest size classes of fish evaluated at the lowest Hg concentration benchmarks were 0.73 (potential health risks to fish themselves), 0.90 (potential health risk to predatory fish that consume Hg contaminated fish), and 0.97 (potential for restricted fish consumption by humans), but diminished to essentially zero at the highest benchmarks and smallest fish size classes. Exceedances of benchmarks are likely to have deleterious health effects on fish and limit recommended amounts of fish humans consume in western Canada and the United States. Results presented here are not intended to subvert or replace local fish Hg data or consumption advice, but provide a basis for identifying areas of potential health risk and developing more focused future research and monitoring efforts.

  17. Geochemistry of Carboniferous low metamorphic grade sedimentary and tholeiitic igneous rocks in the western Acatlán complex, southern Mexico: deposition along the active western margin of Pangea

    National Research Council Canada - National Science Library

    Ortega Obregón, Carlos; Duncan Keppie, J; Brendan Murphy, J


    Low grade metasedimentary rocks in the western Acatlán complex (Olinalá area) of southern Mexico occur in two units termed here the Progreso and Zumpango units of Lower and middle Carboniferous ages, respectively...

  18. Sedimentary environments in the south-western Barents Sea during the last deglaciation and the Holocene: a case study outside the Ingøydjupet trough

    Directory of Open Access Journals (Sweden)

    Mauro Pau


    Full Text Available A lithological and foraminiferal study of newly acquired sediment cores outside the Ingøydjupet (Ingøy Deep trough has been carried out to improve constraints on the last deglacial history in the south-western Barents Sea. Three lithofacies and three foraminiferal facies were identified. The lowermost lithological unit is a diamicton interpreted as glacial till. It contains a low-abundance, ecologically mixed foraminiferal assemblage, presumably resulting from glacial reworking. Above the diamicton, a layer of ice-rafted debris (IRD, likely associated with intensive iceberg production, marks the initial destabilization of the marine-based ice sheet. At this time, ca. 15.6–15.0 Ky B.P., opportunistic foraminiferal species Nonionellina labradorica and Stainforthia spp. reached peak abundance. During the south-western Barents Sea ice-margin retreat, presumably corresponding to the Bølling interstadial, a sequence of glaciomarine laminations was deposited conformably on the layer of IRD. Sedimentation rates were apparently high (estimated about 0.4 cm per year and the foraminiferal fauna was dominated by Elphidium spp. and Cassidulina reniforme, species common for glacier-proximal environments. A hiatus at the top of the deglacial unit is likely linked to the high bottom-current activity associated with a strengthened inflow of Atlantic water masses into the Barents Sea. The uppermost lithological unit is represented by the Holocene marine sandy mud. It contains a high-abundance, high-diversity foraminiferal fauna with common cassidulinids, Cibicides spp., Epistominella pusilla and planktic species.

  19. Risk factors for Mycoplasma bovis-associated disease in farmed bison (Bison bison) herds in western Canada: A case-control study. (United States)

    Bras, Ana L; Barkema, Herman W; Woodbury, Murray; Ribble, Carl; Perez-Casal, Jose; Windeyer, M Claire


    North American bison producers have been attempting to control and prevent Mycoplasma bovis-associated disease without the benefit of bison-specific knowledge. The objective of this study was to determine the clinical presentation of disease associated with M. bovis infection in western Canadian farmed bison, and to identify herd-level risk factors for M. bovis-associated disease. Bison producers (n=49) from western Canada (Manitoba, Saskatchewan, Alberta, and British Columbia) were selected for a 1:2 case-control study. Data were collected by an in-person interview using a questionnaire regarding clinical presentations of outbreaks and herd-level management factors. Risk factors associated with M. bovis outbreaks were identified using multivariable logistic regression analysis. All 17 case herds had a laboratory-confirmed diagnosis of M. bovis infection within the last 5 years. In 11 (65%) of the 17 case herds, disease associated with M. bovis infection recurred in subsequent years. Overall, 88% of case herds had recently introduced bison that later developed clinical signs associated with M. bovis infection. Within a bison operation, a median of 8% (Inter Quartile Range [IQR]: 3-11%) developed clinical signs: lameness, reluctance to move, swollen joints, difficulty breathing, coughing, sluggishness, and loss of body condition. Also, calving percentage the year after the first M. bovis outbreak was lower than calving percentage the year before the outbreak. Herd-level mortality risk during the first M. bovis outbreak in case herds ranged from 0.5 to 50% (median 5%, IQR: 3-10%) and the median case fatality risk was 100%. Case herds were more likely than control herds to have a feedlot unit (OR=7), to receive regular visits from rental trailers or trailers from other farms (OR=15), to annually vaccinate bison (OR=7), and to lose at least one bison due to fatal respiratory disease in the previous year (OR=9). These findings will aid development of evidence

  20. Transport of trace metals (Mn, Fe, Ni, Zn and Cd) in the western Arctic Ocean (Chukchi Sea and Canada Basin) in late summer 2012 (United States)

    Kondo, Yoshiko; Obata, Hajime.; Hioki, Nanako; Ooki, Atsushi; Nishino, Shigeto; Kikuchi, Takashi; Kuma, Kenshi


    Distributions of trace metals (Mn, Fe, Ni, Zn and Cd) in the western Arctic Ocean (Chukchi Sea and Canada Basin) in September 2012 were investigated to elucidate the mechanisms behind the transport of these metals from the Chukchi Shelf to the Canada Basin. Filtered (melting sea-ice, influenced trace metal concentrations. The distribution patterns and concentration ranges were generally similar between the D and TD fractions for Ni, Zn and Cd, which indicate that Ni, Zn and Cd were present mainly in their dissolved forms, whereas the concentrations of TD-Fe and TD-Mn were generally higher than those of D-Fe and D-Mn, respectively. These results are consistent with the results of previous studies of this region. For both Fe and Mn, labile particulate (LP) concentrations (the difference between the TD and D fractions, which is acid-leachable fraction in the particles during storage at pH 1.5-1.6) were highest in the near-bottom waters of the Chukchi Shelf region. The relationships between the distance from the shelf break and the concentrations of trace metals revealed that Fe and Mn concentrations in halocline waters tended to decrease logarithmically with distance, whereas changes in the concentrations of Ni, Zn, Cd and phosphate with distance were small. These results suggest that the distributions of Fe and Mn were controlled mainly by input from shelf sediment and removal through scavenging processes. Based on the phase distributions of Fe and Mn, which were calculated as ratios between the LP and D fractions, different behaviors between Fe and Mn were expressed during lateral transportation. The concentration of TD-Fe declined rapidly via removal of LP-Fe from the water column, whereas the concentration of TD-Mn declined more slowly through the transformation of D-Mn into LP-Mn. In contrast, the concentrations of D-Cd, D-Zn and D-Ni were more strongly correlated with phosphate levels, which suggest that, like phosphate, the distributions of Cd, Zn and Ni were

  1. Education as a Social Determinant of Health: Issues Facing Indigenous and Visible Minority Students in Postsecondary Education in Western Canada

    Directory of Open Access Journals (Sweden)

    Gavin Lam


    Full Text Available The level of educational attainment is increasingly being recognized as an important social determinant of health. While higher educational attainment can play a significant role in shaping employment opportunities, it can also increase the capacity for better decision making regarding one’s health, and provide scope for increasing social and personal resources that are vital for physical and mental health. In today’s highly globalized knowledge based society postsecondary education (PSE is fast becoming a minimum requirement for securing employment that can afford young adults the economic, social and personal resources needed for better health. Canada ranks high among OECD countries in terms of advanced education, with 66% of Canadians having completed some form of postsecondary education. Yet youth from low income indigenous and visible minority (LIIVM backgrounds continue to be poorly represented at PSE levels. The current study aimed to understand the reasons for this poor representation by examining the experiences of LIIVM students enrolled in a postsecondary program. Findings show that the challenges they faced during the course of their study had an adverse impact on their health and that improving representation of these students in PSE will require changes at many levels.

  2. Effects of a Severe Mountain Pine Beetle Epidemic in Western Alberta, Canada under Two Forest Management Scenarios

    Directory of Open Access Journals (Sweden)

    Richard R. Schneider


    Full Text Available We used a simulation model to investigate possible effects of a severe mountain pine beetle (Dendroctonus ponderosae Hopkins epidemic under two management scenarios in Alberta, Canada. Our simulated outbreak was based on the current epidemic in British Columbia, which may kill close to 80% of the province's pine volume. Our two management scenarios were conventional harvest and a pine-reduction strategy modeled on a component of Alberta's Mountain Pine Beetle Management Strategy. The pine strategy seeks to reduce the number of susceptible pine stands by 75% over the next 20 years through targeted harvesting by the forest industry. Our simulations showed that the pine strategy could not be effectively implemented, even if the onset of the beetle outbreak was delayed for 20 years. Even though we increased mill capacity by 20% and directed all harvesting to high volume pine stands during the pine strategy's surge cut, the amount of highly susceptible pine was reduced by only 43%. Additional pine volume remained within mixed stands that were not targeted by the pine strategy. When the outbreak occurred in each scenario, sufficient pine remained on the landscape for the beetle to cause the timber supply to collapse. Alternative management approaches and avenues for future research are discussed.

  3. A study of the composition, characteristics, and origin of modern driftwood on the western coast of Nunavik (Quebec, Canada) (United States)

    Steelandt, Stéphanie; Marguerie, Dominique; Bhiry, Najat; Delwaide, Ann


    Data concerning driftwood is of value to researchers in fields as diverse as oceanography, geomorphology, and human occupation. Yet studies on the subject in the Canadian Arctic have only recently been carried out, and the present study is the first in Nunavik (northeastern Canada). This paper documents the composition, characteristics, and origin of modern driftwood pieces on the beaches of the eastern coast of Hudson Bay. A total of 1057 samples from Ivujivik, Akulivik, Inukjuak, and Umiujaq were identified as belonging to four coniferous species (Picea sp., Larix sp., Abies sp. likely balsamea, and Thuja sp. likely occidentalis) and four deciduous species (Salix sp., Populus sp., Alnus sp., and Betula sp., likely papyrifera). Spruce largely predominate; white birch, white cedar, and fir are rare. The presence of the latter species proves that some of the wood originated from south-southeast of James Bay. Driftwood found in the southern area (Umiujaq) are more numerous, larger, and less degraded than driftwood in the north (Ivujivik). However, many large coniferous samples were found as far north as Akulivik, indicating that they likely traveled a great distance, unlike the smaller wood specimens (especially deciduous samples). All of the wood that we analyzed died relatively young, with an average age of 63 years for conifers and 23 years for deciduous. Measurements of ring widths and the cross-dating of samples with existing reference chronologies of living trees along Hudson Bay and James Bay revealed several possible correlations and origins for wood found in same areas.

  4. Sylvatic trichinosis in Canada.


    Smith, H. J.; Snowdon, K E


    Pepsin digestion of musculature from 2253 animals revealed that sylvatic trichinosis occurred in various species of mammals from the eastern to the western Arctic and extended down into the Rocky Mountain and Foothills regions of western Canada. Infections were demonstrated in Arctic fox, red fox, wolf, raccoon, coyote, lynx, bobcat and dog.

  5. Topographic control of snow distribution in an alpine watershed of western Canada inferred from spatially-filtered MODIS snow products

    Directory of Open Access Journals (Sweden)

    J. Tong


    Full Text Available A spatial filter (SF is used to reduce cloud coverage in Moderate Resolution Imaging Spectroradiometer (MODIS 8-day maximum snow cover extent products (MOD10A2 from 2000–2007, which are obtained from MODIS daily snow cover extent products (MOD10A1, to assess the topographic control on snow cover fraction (SCF and snow cover duration (SCD in the Quesnel River Basin (QRB of British Columbia, Canada. Results show that the SF reduces cloud coverage and improves by 2% the accuracy of snow mapping in the QRB. The new product developed using the SF method shows larger SCF and longer SCD than MOD10A2, with higher altitudes experiencing longer snow cover and perennial snow above 2500 m. The gradient of SCF with elevation (d(SCF/dz during the snowmelt season is 8% (100 m−1. The average ablation rates of SCF are similar for different 100 m elevation bands at about 5.5% (8 days−1 for altitudes <1500 m with decreasing values with elevation to near 0% (8 days−1 for altitudes >2500 m. Different combinations of slopes and aspects also affect the SCF with a maximum difference of 20.9% at a given time. Correlation coefficients between SCD and elevation attain 0.96 (p<0.001. Mean gradients of SCD with elevation are 3.8, 4.3, and 11.6 days (100 m−1 for the snow onset season, snowmelt season, and entire year, respectively. The SF decreases the standard deviations of SCDs compared to MOD10A2 with a maximum difference near 0.6 day, 0.9 day, and 1.0 day for the snow onset season, snowmelt season, and entire year, respectively.

  6. Access to health services in Western Newfoundland, Canada: Issues, barriers and recommendations emerging from a community-engaged research project

    Directory of Open Access Journals (Sweden)

    Janelle Hippe


    Full Text Available Research indicates that people living in rural and remote areas of Canada face challenges to accessing health services. This article reports on a community-engaged research project conducted by investigators at Memorial University of Newfoundland in collaboration with the Rural Secretariat Regional Councils and Regional Partnership Planners for the Corner Brook–Rocky Harbour and Stephenville–Port aux Basques Rural Secretariat Regions of Newfoundland and Labrador. The aim of this research was to gather information on barriers to accessing health services, to identify solutions to health services’ access issues and to inform policy advice to government on enhancing access to health services. Data was collected through: (1 targeted distribution of a survey to communities throughout the region, and (2 informal ‘kitchen table’ discussions to discuss health services’ access issues. A total of 1049 surveys were collected and 10 kitchen table discussions were held. Overall, the main barriers to care listed in the survey included long wait times, services not available in the area and services not available at time required. Other barriers noted by survey respondents included transportation problems, financial concerns, no medical insurance coverage, distance to travel and weather conditions. Some respondents reported poorer access to maternal/child health and breast and cervical screening services and a lack of access to general practitioners, pharmacy services, dentists and nurse practitioners. Recommendations that emerged from this research included improving the recruitment of rural physicians, exploring the use of nurse practitioners, assisting individuals with travel costs,  developing specialist outreach services, increasing use of telehealth services and initiating additional rural and remote health research. Keywords: rural, remote, healthcare, health services, social determinants of health

  7. Proceedings of the OPAS oil and gas sector symposium : Human resources in the western Canada oil and gas industry

    Energy Technology Data Exchange (ETDEWEB)



    The Office for Partnerships in Advanced Skills (OPAS), Western Office organized this conference to discuss critical human resource issues in the oil and gas sector. In order to gain a broad perspective and different viewpoints, OPAS brought together representatives from the oil and gas industry, academia, the Alberta Energy and Utilities Board, and Alberta's Ministry of Human Resources and Employment. Topics of discussion included market trends, skills shortages and training development needs to respond to difficulties in recruiting in the areas of thermal enhanced oil recovery technologies and unconventional gas technologies. An 18 question survey conducted prior to the symposium revealed that the majority of respondents do not think that the current post secondary curriculum adequately meets the oil and gas industry's employment skill requirements. The challenges in designing and implementing industry specific programs were then discussed along with the timeline needed to develop an appropriate program and get graduates into the marketplace. The recommended initiatives resulting from the symposium discussions were then presented. refs., tabs., figs.

  8. A Tale of Two Sites: Lessons on Leadership from the Implementation of a Long-term Care Delivery Model (CDM) in Western Canada (United States)

    Cloutier, Denise; Cox, Amy; Kampen, Ruth; Kobayashi, Karen; Cook, Heather; Taylor, Deanne; Gaspard, Gina


    Residential, long-term care serves vulnerable older adults in a facility-based environment. A new care delivery model (CDM) designed to promote more equitable care for residents was implemented in a health region in Western Canada. Leaders and managers faced challenges in implementing this model alongside other concurrent changes. This paper explores the question: How did leadership style influence team functioning with the implementation of the CDM? Qualitative data from interviews with leadership personnel (directors and managers, residential care coordinators and clinical nurse educators), and direct care staff (registered nurses, licensed practical nurses, health care aides, and allied health therapists), working in two different facilities comprise the main sources of data for this study. The findings reveal that leaders with a servant leadership style were better able to create and sustain the conditions to support successful model implementation and higher team functioning, compared to a facility in which the leadership style was less inclusive and proactive, and more resistant to the change. Consequently, staff at the second facility experienced a greater sense of overload with the implementation of the CDM. This study concludes that strong leadership is key to facilitating team work and job satisfaction in a context of change. PMID:27417591

  9. A Tale of Two Sites: Lessons on Leadership from the Implementation of a Long-term Care Delivery Model (CDM) in Western Canada. (United States)

    Cloutier, Denise; Cox, Amy; Kampen, Ruth; Kobayashi, Karen; Cook, Heather; Taylor, Deanne; Gaspard, Gina


    Residential, long-term care serves vulnerable older adults in a facility-based environment. A new care delivery model (CDM) designed to promote more equitable care for residents was implemented in a health region in Western Canada. Leaders and managers faced challenges in implementing this model alongside other concurrent changes. This paper explores the question: How did leadership style influence team functioning with the implementation of the CDM? Qualitative data from interviews with leadership personnel (directors and managers, residential care coordinators and clinical nurse educators), and direct care staff (registered nurses, licensed practical nurses, health care aides, and allied health therapists), working in two different facilities comprise the main sources of data for this study. The findings reveal that leaders with a servant leadership style were better able to create and sustain the conditions to support successful model implementation and higher team functioning, compared to a facility in which the leadership style was less inclusive and proactive, and more resistant to the change. Consequently, staff at the second facility experienced a greater sense of overload with the implementation of the CDM. This study concludes that strong leadership is key to facilitating team work and job satisfaction in a context of change.

  10. Environmental- and health-risk-induced remediation design for benzene-contaminated groundwater under parameter uncertainty: a case study in Western Canada. (United States)

    Fan, X; He, L; Lu, H W; Li, J


    This study proposes an environmental- and health-risk-induced remediation design approach for benzene-contaminated groundwater. It involves exposure frequency and intake rates that are important but difficult to be exactly quantified as breakthrough point. Flexible health-risk control is considered in the simulation and optimization work. The proposed approach is then applied to a petroleum-contaminated site in western Canada. Different situations about remediation durations, public concerns, and satisfactory degrees are addressed by the approach. The relationship between environmental standards and health-risk limits is analyzed, in association with their effect on remediation costs. Insights of three uncertain factors (i.e. exposure frequency, intake rate and health-risk threshold) for the remediation system are also explored, on a basis of understanding their impacts on health risk as well as their importance order. The case study results show that (1) nature attenuation plays a more important role in long-term remediation scheme than the pump-and-treat system; (2) carcinogenic risks have greater impact on total pumping rates than environmental standards for long-term remediation; (3) intake rates are the second important factor affecting the remediation system's performance, followed by exposure frequency; (4) the 10-year remediation scheme is the most robust choice when environmental and health-risk concerns are not well quantified. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. A Tale of Two Sites: Lessons on Leadership from the Implementation of a Long-term Care Delivery Model (CDM in Western Canada

    Directory of Open Access Journals (Sweden)

    Denise Cloutier


    Full Text Available Residential, long-term care serves vulnerable older adults in a facility-based environment. A new care delivery model (CDM designed to promote more equitable care for residents was implemented in a health region in Western Canada. Leaders and managers faced challenges in implementing this model alongside other concurrent changes. This paper explores the question: How did leadership style influence team functioning with the implementation of the CDM? Qualitative data from interviews with leadership personnel (directors and managers, residential care coordinators and clinical nurse educators, and direct care staff (registered nurses, licensed practical nurses, health care aides, and allied health therapists, working in two different facilities comprise the main sources of data for this study. The findings reveal that leaders with a servant leadership style were better able to create and sustain the conditions to support successful model implementation and higher team functioning, compared to a facility in which the leadership style was less inclusive and proactive, and more resistant to the change. Consequently, staff at the second facility experienced a greater sense of overload with the implementation of the CDM. This study concludes that strong leadership is key to facilitating team work and job satisfaction in a context of change.

  12. Controlled Release Urea as a Nitrogen Source for Spring Wheat in Western Canada: Yield, Grain N Content, and N Use Efficiency

    Directory of Open Access Journals (Sweden)

    Lenz Haderlein


    Full Text Available Controlled release nitrogen (N fertilizers have been commonly used in horticultural applications such as turf grasses and container-grown woody perennials. Agrium, a major N manufacturer in North and South America, is developing a low-cost controlled release urea (CRU product for use in field crops such as grain corn, canola, wheat, and other small grain cereals. From 1998 to 2000, 11 field trials were conducted across western Canada to determine if seed-placed CRU could maintain crop yields and increase grain N and N use efficiency when compared to the practice of side-banding of urea N fertilizer. CRU was designed to release timely and adequate, but not excessive, amounts of N to the crop. Crop uptake of N from seed-placed CRU was sufficient to provide yields similar to those of side-banded urea N. Grain N concentrations of the CRU treatments were higher, on average, than those from side-banded urea, resulting in 4.2% higher N use efficiency across the entire N application range from 25 to 100 kg ha-1. Higher levels of removal of N in grain from CRU compared to side-banded urea can result in less residual N remaining in the soil, and limit the possibility of N losses due to denitrification and leaching.

  13. Influence of organizational context on nursing home staff burnout: A cross-sectional survey of care aides in Western Canada. (United States)

    Chamberlain, Stephanie A; Gruneir, Andrea; Hoben, Matthias; Squires, Janet E; Cummings, Greta G; Estabrooks, Carole A


    Our study examined care aide characteristics, organizational context, and frequency of dementia-related resident responsive behaviours associated with burnout. Burnout is the experience of emotional exhaustion, cynicism, and professional inefficacy. Care aide burnout has implications for turnover, staff health, and quality of care. We used surveys collected from 1194 care aides from 30 urban nursing homes in three Western Canadian provinces. We used a mixed-effects regression analysis to assess care aide characteristics, dementia-related responsive behaviours, unit and facility characteristics, and organizational context predictors of care aide burnout. We measured burnout using the Maslach Burnout Inventory, Short Form. We found that care aides were at high risk for emotional exhaustion and cynicism, but report high professional efficacy. Statistically significant predictors of emotional exhaustion included English as a second language, medium facility size, organizational slack-staff, organizational slack-space, health (mental and physical) and dementia-related responsive behaviours. Statistically significant predictors of cynicism were care aide age, English as a second language, unit culture, evaluation (feedback of data), formal interactions, health (mental and physical) and dementia-related responsive behaviours. Statistically significant predictors of professional efficacy were unit culture and structural resources. Greater care aide job satisfaction was significantly associated with increased professional efficacy. This study suggests that individual care aide and organization features are both predictive of care aide burnout. Unlike care aide or structural characteristics of the facility elements of the organizational context are potentially modifiable, and therefore amenable to intervention. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Gray-cheeked Thrush (Catharus minimus minimus distribution and habitat use in a montane forest landscape of western Newfoundland, Canada

    Directory of Open Access Journals (Sweden)

    Darroch M. Whitaker


    Full Text Available Once abundant, the Newfoundland Gray-cheeked Thrush (Catharus minimus minimus has declined by as much as 95% since 1975. Underlying cause(s of this population collapse are not known, although hypotheses include loss of winter habitat and the introduction of red squirrels (Tamiasciurus hudsonicus to Newfoundland. Uncertainties regarding habitat needs are also extensive, and these knowledge gaps are an impediment to conservation. We investigated neighborhood (i.e., within 115 m [4.1 ha] and landscape scale (i.e., within 1250 m [490.8 ha] habitat associations of Gray-cheeked Thrush in a 200-km² study area in the Long Range Mountains of western Newfoundland, where elevations range from 300-600 m and landcover was a matrix of old growth fir forest, 6- to 8-year-old clearcuts, coniferous scrub, bogs, and barrens. Thrushes were restricted to elevations above ~375 m, and occurrence was strongly positively related to elevation. Occurrence was also positively related to cover of tall scrub forest at the neighborhood scale, and at the landscape scale showed curvilinear relations with the proportion of both tall scrub and old growth forest that peaked with intermediate amounts of cover. Occurrence of thrushes was also highest when clearcuts made up 60%-70% of neighborhood landcover, but was negatively related to cover of clearcuts in the broader landscape. Finally, occurrence was highest in areas having 50% cover of partially harvested forest (strip cuts or row cuts at the neighborhood scale, but because this treatment was limited to one small portion of the study area, this finding may be spurious. Taken together, our results suggest selection for mixed habitats and sensitivity to both neighborhood and landscape-scale habitat. More research is needed on responses of thrushes to forestry, including use of older clearcuts, partially harvested stands, and precommercially thinned clearcuts. Finally, restriction of thrushes to higher elevations is consistent

  15. The linkage between fluvial meander-belt morphodynamics and the depositional record improves paleoenvironmental interpretations, Western Interior Basin, Alberta, Canada (United States)

    Durkin, P.; Hubbard, S. M.


    -belt scale, analysis of changes in morphology over time reveal a decrease in channel-belt width/thickness ratio and sinuosity, which we attribute to the landward migration of the paleo-backwater limit due to the oncoming and overlying transgression of the Cretaceous Boreal Sea into the Western Interior Basin.

  16. Interactions of polychlorinated biphenyls and organochlorine pesticides with sedimentary organic matter of retrogressive thaw slump-affected lakes in the tundra uplands adjacent to the Mackenzie Delta, NT, Canada (United States)

    Eickmeyer, David C.; Kimpe, Linda E.; Kokelj, Steve V.; Pisaric, Michael F. J.; Smol, John P.; Sanei, Hamed; Thienpont, Joshua R.; Blais, Jules M.


    Using a comparative spatial analysis of sediment cores from eight lakes in tundra uplands adjacent to the Mackenzie Delta, NT, we examined how the presence of retrogressive thaw slumps on lake shores affected persistent organic pollutant (POPs, including polychlorinated biphenyls and organochlorine pesticides) accumulation in lake sediments. Sediments of slump-affected lakes contained higher total organic carbon (TOC)-normalized POP concentrations than nearby reference lakes that were unaffected by thaw slumps. Mean focus-corrected inorganic sedimentation rates were positively related to TOC-normalized contaminant concentrations, explaining 58-94% of the variation in POP concentrations in sediment, suggesting that reduced organic carbon in slump-affected lake water results in higher concentrations of POPs on sedimentary organic matter. This explanation was corroborated by an inverse relationship between sedimentary POP concentrations and TOC content of the lake water. Inferred chlorophyll a, S2, and S3 carbon fluxes to sediment were not significantly correlated to POP fluxes. Higher POP concentrations observed in sediment of slump-affected lakes are best explained by simple solvent switching processes of hydrophobic organic contaminants onto a smaller pool of available organic carbon when compared to neighboring lakes unaffected by thaw slump development.

  17. E/I corrected paleolatitudes for the sedimentary rocks of the Baja British Columbia hypothesis (United States)

    Krijgsman, Wout; Tauxe, Lisa


    Paleomagnetic inclinations from sediments of the western terranes of Canada are consistently too shallow for their reconstructed paleogeographic positions. Two contradicting explanations for these discrepancies are: (1) terranes have been displaced northward with respect to the stable American craton by several thousands of kilometres between the Late Cretaceous (˜ 75 Ma) and the Eocene (˜50 Ma) and (2) sedimentary inclination error has caused a shallow bias in the paleomagnetic directions. Here, we apply the elongation/inclination (E/I) method to paleomagnetic data sets from sedimentary rocks of supposedly allochtonous terranes of western North America to correct for inclination flattening. Our results indicate that the paleomagnetic directions from the continental Silverquick sediments (95-92 Ma) of southern British Colombia are not seriously affected by inclination error, because the magnetic signal most likely concerns a chemical remanent magnetisation (CRM). In contrast, the marine sediments of the Nanaimo Group (84-72 Ma) of Vancouver Island region appear seriously affected by inclination flattening ( f = 0.7) and the E/I corrected mean inclinations are about 9° steeper than the original data. We arrive at corrected inclinations/paleolatitudes of I** = 57°/ λ = 38°N for the Silverquick and I** = 55°/ λ = 36°N for the Nanaimo sediments. Our corrected paleolatitudes indicate that the Canadian terranes were indeed located adjacent to the Baja Californian margin during the Late Cretaceous, thus supporting the Baja BC hypothesis.

  18. Limnological regime shifts caused by climate warming and Lesser Snow Goose population expansion in the western Hudson Bay Lowlands (Manitoba, Canada). (United States)

    MacDonald, Lauren A; Farquharson, Nicole; Merritt, Gillian; Fooks, Sam; Medeiros, Andrew S; Hall, Roland I; Wolfe, Brent B; Macrae, Merrin L; Sweetman, Jon N


    Shallow lakes are dominant features in subarctic and Arctic landscapes and are responsive to multiple stressors, which can lead to rapid changes in limnological regimes with consequences for aquatic resources. We address this theme in the coastal tundra region of Wapusk National Park, western Hudson Bay Lowlands (Canada), where climate has warmed during the past century and the Lesser Snow Goose (LSG; Chen caerulescens caerulescens) population has grown rapidly during the past ∽40 years. Integration of limnological and paleolimnological analyses documents profound responses of productivity, nutrient cycling, and aquatic habitat to warming at three ponds ("WAP 12", "WAP 20", and "WAP 21″), and to LSG disturbance at the two ponds located in an active nesting area (WAP 20, WAP 21). Based on multiparameter analysis of (210)Pb-dated sediment records from all three ponds, a regime shift occurred between 1875 and 1900 CE marked by a transition from low productivity, turbid, and nutrient-poor conditions of the Little Ice Age to conditions of higher productivity, lower nitrogen availability, and the development of benthic biofilm habitat as a result of climate warming. Beginning in the mid-1970s, sediment records from WAP 20 and WAP 21 reveal a second regime shift characterized by accelerated productivity and increased nitrogen availability. Coupled with 3 years of limnological data, results suggest that increased productivity at WAP 20 and WAP 21 led to atmospheric CO2 invasion to meet algal photosynthetic demand. This limnological regime shift is attributed to an increase in the supply of catchment-derived nutrients from the arrival of LSG and their subsequent disturbance to the landscape. Collectively, findings discriminate the consequences of warming and LSG disturbance on tundra ponds from which we identify a suite of sensitive limnological and paleolimnological measures that can be utilized to inform aquatic ecosystem monitoring.

  19. Monitoring the species of arsenic, chromium and nickel in milled coal, bottom ash and fly ash from a pulverized coal-fired power plant in western Canada. (United States)

    Goodarzi, F; Huggins, F E


    The concentration of As, Cr and Ni and their speciation (As3+;5+, Cr3+;6+ and Ni0;2+) in milled coal, bottom ash and ash collected by electrostatic precipitator (ESP) from a coal fired-power plant in western Canada were determined using HGAAS, ICP-AES and XANES. The chemical fractionation of these elements was also determined by a sequential leaching procedure, using deionized water, NH4OAC and HCI as extracting agents. The leachate was analyzed by ICP-AES. Arsenic in the milled coal is mostly associated with organic matter, and 67% of this arsenic is removed by ammonium acetate. This element is totally removed from milled coal after extraction with HCI. Arsenic occurs in both the As3+ and the As5+ oxidation states in the milled coal, while virtually all (>90%) of the arsenic in bottom ash and fly ash appears to be in the less toxic arsenate (As5+) form. Both Ni and Cr in the milled coal are extracted by HCI, indicating that water can mobilize Ni and Cr in an acidic environment. The chromium is leached by water from fly ash as a result of the high pH of the water, which is induced during the leaching. Ammonium acetate removes Ni from bottom ash through an ion exchange process. Chromium in milled coal is present entirely as Cr3+, which is an essential human trace nutrient. The Cr speciation in bottom ash is a more accentuated version of the milled coal and consists mostly of the Cr3+ species. Chromium in fly ash is mostly Cr3+, with significant contamination by stainless-steel from the installation itself.

  20. Limnological regime shifts caused by climate warming and Lesser Snow Goose population expansion in the western Hudson Bay Lowlands (Manitoba, Canada) (United States)

    MacDonald, Lauren A; Farquharson, Nicole; Merritt, Gillian; Fooks, Sam; Medeiros, Andrew S; Hall, Roland I; Wolfe, Brent B; Macrae, Merrin L; Sweetman, Jon N


    Shallow lakes are dominant features in subarctic and Arctic landscapes and are responsive to multiple stressors, which can lead to rapid changes in limnological regimes with consequences for aquatic resources. We address this theme in the coastal tundra region of Wapusk National Park, western Hudson Bay Lowlands (Canada), where climate has warmed during the past century and the Lesser Snow Goose (LSG; Chen caerulescens caerulescens) population has grown rapidly during the past ∽40 years. Integration of limnological and paleolimnological analyses documents profound responses of productivity, nutrient cycling, and aquatic habitat to warming at three ponds (“WAP 12”, “WAP 20”, and “WAP 21″), and to LSG disturbance at the two ponds located in an active nesting area (WAP 20, WAP 21). Based on multiparameter analysis of 210Pb-dated sediment records from all three ponds, a regime shift occurred between 1875 and 1900 CE marked by a transition from low productivity, turbid, and nutrient-poor conditions of the Little Ice Age to conditions of higher productivity, lower nitrogen availability, and the development of benthic biofilm habitat as a result of climate warming. Beginning in the mid-1970s, sediment records from WAP 20 and WAP 21 reveal a second regime shift characterized by accelerated productivity and increased nitrogen availability. Coupled with 3 years of limnological data, results suggest that increased productivity at WAP 20 and WAP 21 led to atmospheric CO2 invasion to meet algal photosynthetic demand. This limnological regime shift is attributed to an increase in the supply of catchment-derived nutrients from the arrival of LSG and their subsequent disturbance to the landscape. Collectively, findings discriminate the consequences of warming and LSG disturbance on tundra ponds from which we identify a suite of sensitive limnological and paleolimnological measures that can be utilized to inform aquatic ecosystem monitoring. PMID:25750718

  1. Cow attributes, herd management, and reproductive history events associated with the risk of nonpregnancy in cow-calf herds in Western Canada. (United States)

    Waldner, C L; García Guerra, A


    To identify herd management and cow characteristics associated with the reproductive success of cow-calf herds in Western Canada, 33,391 beef cows were followed from the beginning of the breeding season in 2001 through pregnancy testing in 2002. Breeding management and cow-level risk factors such as age, body condition score (BCS), and previous reproductive history, were measured through a series of herd visits by project personnel and records maintained by the herd owner. Pregnancy status was measured in 205 herds in the fall of 2001 and again in 200 herds in the fall of 2002. Cows least likely to be pregnant in the fall of the year were 10 years old or older, exposed to a bull less than 84 days, had a BCS ≤5 of 9 at pregnancy testing, <5 of 9 before calving, and lost condition between calving and the start of the breeding season, or had a prebreeding BCS <5 of 9 with a loss of condition between breeding and pregnancy testing. Other factors identified that decreased the likelihood of pregnancy in at least one of the 2 years included being a heifer or being a cow exposed to breeding after her first calf, and using a single bull on breeding pasture. Cows vaccinated for bovine viral diarrhea virus and infectious bovine rhinotracheitis and bred on community pastures were more likely to be pregnant than cows that were not vaccinated and bred on community pastures. Cows bred on community pastures that were not vaccinated were also less likely to be pregnant than cows that were not on community pastures regardless of vaccination status. Calving-associated events such as twin birth, Cesarean section or malpresentation, problems such as uterine prolapse or retained placentas, abortion or calf death within 1 hour after birth, or calving late after the start of the breeding season, were also associated with fewer pregnancies after accounting for all other factors.

  2. Spatio-temporal dynamics of evapotranspiration from forested, ephemeral wetlands and its implication for hydrologic connectivity in the Western Boreal Plain in Alberta, Canada (United States)

    Hurley, Alexander; Kettridge, Nicholas; Devito, Kevin; Hokanson, Kelly; Leonard, Rhoswen; Krause, Stefan; Waddington, James Michael


    In catchments where hydrologic connectivity is predominantly controlled by storage-threshold dynamics, landscape units promoting water transmission can be crucial for overall ecohydrological functioning. In Canada's Western Boreal Plain, ephemeral wetlands surrounded by upland forests on deep and coarse, glacial deposits are examples of such units. In the sub-humid climate, their importance is exacerbated due to regional, multi-year water deficits, resulting from high evapotranspirative (ET) demand coinciding with most of the annual precipitation and its variability between years. Yet, these ephemeral wetlands frequently saturate during small rain events; hence, they likely play a key role in supplying water to adjacent and downstream systems in both dry and wet periods. We assess factors controlling water losses from these wetlands to the atmosphere (via the soil surface and vegetation), how they change over time (i.e. throughout the growing season), and the extent to which they vary in space. Our goal is to generate process-based understanding of ET dynamics and to determine potential feedbacks that reduce ET losses, maximizing the magnitude and period over which these landscape units may act as water sources. We hypothesize that the following mechanisms enhance the ascribed water transmitting function: (1) external and internal shading reduces incident radiation and therefore available energy to drive ET; this effect increases with leaf area, but is counter-acted by interception. (2) Vegetation structure reduces turbulent exchange with air masses above the canopy, thereby decreasing humidity gradients driving ET. (3) High, near-surface soil tensions during periods of drying limit rates of evaporation. We applied a combined measurement approach to assess spatial and temporal dynamics of ET in the 2016 growing season (May - August) and gathered additional data to assess abiotic and biotic controls on ET rates. We continuously measured ET from the wetland's surface

  3. The role of compressional tectonics, sedimentary transport and mineral composition on AMS and AARM fabrics. A case study of the flysch from the Dukla nappe, Outer Western Carpatians, Poland (United States)

    Kiss, Dániel; Márton, Emő; Tokarski, Antek K.


    The Carpathians belong to the European Alpine system. The Polish segment of the Western Outer Carpathians is a north-verging thrust-and-fold belt composed largely of Lower Cretaceous to Lower Miocene flysch. The belt comprises the Skole, Subsilesian, Silesian, Dukla and Magura rootless nappes. Anisotropy studies were carried out both in Oligocene turbidite sequences of the Dukla nappe and in the olistostrome of the Lipowica quarry. For the study 102 individually oriented cores were drilled at nine geographically distributed localities. At each locality mudstones/claystones were sampled, except Lipowica quarry, where silt and sandstone were also drilled. Because of the relatively low susceptibilities (1-3*10-4 SI), paramagnetic minerals can be important contributors to the AMS fabric. AMS and AARM measurements were carried out and the fabrics were compared. Despite of the weak AMS lineations, the mean lineation direction is well defined in all cases on site/locality level. With one exception where the lineation is perpendicular to the bedding plane (due to the presence of siderite), the AMS lineations can be interpreted as due to compressional tectonics. Concerning the AARM lineations they are highly scattered in the sandstone, show a tendency for alignment in the silt and some of the mudstone/claystone sites, and are well clustered in the other cases. The AARM lineations for four localities correlate to the AMS, and the local strike. The AARM lineation of the siderite bearing rock is also sub-parallel to the local strike. In the remaining cases the AARM linations are suspected to be related to sedimentary transport. Due to the lack of solemarks at most localities this will be investigated systematically with photo-statistical grain shape analysis in oriented thin sections. X-ray diffraction measurements also will be carried out to identify the paramagnetic contributors to the AMS. Acknowledgments: This work was partly financed by the Hungarian Research Fund (OTKA

  4. Associations between oil- and gas-well sites, processing facilities, flaring, and beef cattle reproduction and calf mortality in western Canada. (United States)

    Waldner, C L; Ribble, C S; Janzen, E D; Campbell, J R


    From the fall of 1992 through calving 1996, detailed cow breeding outcome records were maintained actively for seven large cow-calf herds in western Canada. The numbers of mature females in the study for the breeding seasons beginning in 1992, 1993, 1994, and 1995 were 1122, 1177, 1251, and 1236, respectively. Outcomes included pregnancy status, calving interval, and the occurrence of twins, abortions, stillbirths, and neonatal mortality. Information also was collected on other risk factors known to influence beef-herd health and productivity. Detailed maps of active and inactive oil and natural-gas sites, batteries, compressor stations and processing plants were verified. Records of flaring activity at each facility were obtained from the government regulatory agency. Each flaring site then was classified as sour or sweet based on the presence or absence of hydrogen sulfide in the flared gas. A detailed inventory was prepared itemizing the type and number of facilities within 1.6 km (1 mile) of the center of each quarter section used for pasture. The total volume of gas flared within 1.6 km of the center of each pasture was determined for each month of the study. Appropriate risk periods where specified for each outcome and a cumulative exposure calculated for each breeding female (using detailed individual-animal records of cow movements between pastures and herd-management groups). Generalized estimating equations were used to evaluate the association between exposure and outcome and to adjust for potential confounders and clustering of binomial outcomes within herd. Increased risk of non-pregnancy was sometimes associated with exposure to one or more of the following facility types: sour-gas flaring battery facilities, all battery-flaring sites, active gas wells, and larger field facilities. The associations were not, however, consistent among years or even among risk periods for the same year. Facility proximity and flaring were not associated with increased

  5. Geochemistry and Cyclostratigraphy of Magnetic Susceptibility data from the Frasnian-Famennian event interval in western Canada: Insights in the pattern and timing of a biotic crisis (United States)

    Whalen, M. T.; De Vleeschouwer, D.; Sliwinski, M. G.; Claeys, P. F.; Day, J. E.


    Cyclostratigraphic calibration of magnetic susceptibility data along with stable isotopic and geochemical proxy data for redox, productivity, and detrital input from western Canada provide insight into the pace and timing of the Late Devonian, Frasnian-Famennian (F-F) biotic crisis. Two organic-rich shales that, in much of the world, display geochemical anomalies indicating low oxygen conditions and carbon burial characterize the F-F event. These events, referred to as the Lower and Upper Kellwasser events (LKE & UKE), have been linked to the evolutionary expansion of deeply rooted terrestrial forests and the concomitant changes in soil development and chemical weathering and changes in Late Devonian climate. Our geochemical data record relatively high levels of redox sensitive trace metals (Mo, U, V), proxies for biological productivity (Ba, Cu, Ni, Zn), and detrital input (Al, Si, Ti, Zr) during both events. C stable isotopic data generated from organic matter records a 3-4‰ positive excursion during both events. Each event is recorded in lowstand and/or early transgressive facies. These data corroborate hypotheses about enhanced biological productivity, driven by heightened terrestrial detrital input, leading to low oxygen conditions and decreases in biotic diversity during during relatively low stands of Late Devonian sea level. Age dating of such events in deep time is problematic due to insufficient biochronologic control. Each event is within one conodont biostratigraphic zone, with durations on the order of 0.5-1.0 Ma. Time series analysis of high-resolution magnetic susceptibility data identified 16 long eccentricity cycles (405 ky) during the Frasnian stage and one in the earliest Famennian stage. The geochemical anomalies associated with the LKE and UKE are recorded over 7 and 14 m of stratigraphic section respectively. These strata represent only a portion of a 405 ky long eccentricity cycle and astronomical tuning implies that the LKE likely occurred

  6. Western Canada study of animal health effects associated with exposure to emissions from oil and gas field facilities : interpretive overview by the science advisory panel

    Energy Technology Data Exchange (ETDEWEB)

    Guidotti, T.; Nielsen, O.; Berhane, K.; Cohen, B.S.; Hunter, B.; Lasley, B.; Martin, W.; Ribble, C.; Thorne, P.; Tollerud, D.; Witschi, H. [Western Interprovincial Scientific Studies Association, Calgary, AB (Canada). Science Advisory Panel


    The results of a study to determine if chronic exposure to emissions from the oil and gas industry influence the health and reproductive performance of cattle and wildlife in western Canada was presented. Individual cows in herds from Alberta, Saskatchewan and northeastern British Columbia were monitored in pens and pastures to determine their exposure status. Data on other known risk factors such as the cow's age, breed and body condition were collected. The study measured concentrations of sulphur dioxide (SO{sub 2}); hydrogen sulphide (H{sub 2}S); and volatile organic compounds (VOCs) measured as benzene and toluene. Passive air monitors were located on all occupied pastures and wintering areas for each herd. Information on the location of over 39,000 animals from 205 herds on 3355 different parcels of land was recorded at 2 week intervals. Each animal's exposure was then averaged to create cumulative exposure values for biologically relevant risk periods for each outcome. Exposures to fine particulate matter (PM) and polycyclic aromatic hydrocarbons were measured a total of 365 times near the calving area for 32 herds. Five primary health outcomes were studied: (1) nonpregnancy; (2) length of breeding-to-calving interval; (3) abortion; (4) stillbirth; and (5) calf mortality. No associations were found among any of the exposure measures and the risk of nonpregnancy, abortion or stillbirth. Sulphur-containing exposures showed no associations with secondary outcome measures in the respiratory, immune and nervous systems. An association was found between exposure to SO{sub 2} and the increased risk of calf mortality. Findings also suggested that there was a greater risk of lesions in the calf skeletal or cardiac muscle with increased prenatal exposure to SO{sub 2}. Increased exposure to VOCs contributed to a greater risk of calf respiratory and thyroid lesions, and a lower count of CD4 and CD8 T-lymphocytes in calves. The results of a concurrent study on

  7. Economics of fossil fuel substitution and wood product sinks when trees are planted to sequester carbon on agricultural lands in western Canada

    National Research Council Canada - National Science Library

    Stennes, Brad; Krcmar-Nozic, Emina; van Gorkom, Ruud; van Kooten, G Cornelis


    To meet its international commitment to reduce CO 2 output by 7% from the 1990 level by 2012, Canada will rely to some extent on terrestrial carbon uptake, particularly afforestation of marginal agricultural land...


    Institute of Scientific and Technical Information of China (English)

    叶兴树; 高海红; 尤建军; 庄升; 苑国胜


    运用层序地层及沉积相理论对大民屯凹陷西斜坡古近纪沙三段发育的沉积特征进行分析,结果表明:沙三段发育低位、湖侵、高位体系域;大民屯凹陷西斜坡沙三段的沉积相类型可分为冲积扇相、辫状河三角洲相和浊积扇相;前进断裂坡折带控制了大民屯凹陷西斜坡沙三段沉积发育,低位域主要发育冲积扇、辫状河三角洲、滑塌浊积扇,同沉积断裂坡折带之下发育辫状河三角洲、滑塌浊积扇,湖侵域在坡折带之下主要发育滑塌浊积扇、湖相泥岩;高位域西斜坡主要发育冲积扇和辫状河三角洲相沉积,从而沿着西斜坡形成冲积扇相-三角洲相-浊积扇相的沉积模式;沙三中下段,大民屯凹陷荣胜堡洼陷东北斜坡部位受前进断裂破折带控制的沉积砂体及浅湖-半深湖区的浊积扇砂体是形成岩性油气藏有利区带.%Based on the theory of stratigraphy and sedimentary faciesrthe sedimentary feature of Es3 Member in the western slope of Damintun Depression has been analyzed. The Damintun De-pression develops lower stand system tract, transgressive system tract and high stand system tract. Sedimentary facies in Es3 Member in the western slope of Damintun Depression can be divid-ed into alluvial fan, braided river fan-delta and turbidite fan respectively. Sediments in different tract of Es3 Member in Rongshengbao sag is controlled by Qianjin fault slope zone. Alluvial fan, braided river fan-delta and turbidite fan are recognized in lower stand system tract and braided river fan-delta and turbidite fan are found below the fault slope zone. Deep lake mudstone and turbidite fan mainly develop below the fault slope zone in transgressive system tract. Alluvial fan and braided river fan-delta form along the western slope of Rongshnegbao sag. So,the sedimentary model of alluvial fan-braided river fan-delta-turbidite fan is generated in Es3 Member in the western slope of Damintun

  9. Economics of fossil fuel substitution and wood product sinks when trees are planted to sequester carbon on agricultural lands in western Canada

    NARCIS (Netherlands)

    Kooten, van G.C.; Krcmar-Nozic, E.; Stennes, B.; Gorkom, van R.


    To meet its international commitment to reduce CO2 output by 7% from the 1990 level by 2012, Canada will rely to some extent on terrestrial carbon uptake, particularly afforestation of marginal agricultural land. The economics of afforestation is examined for northeastern British Columbia and all of

  10. Evolution of Sedimentary Rocks (United States)

    Veizer, J.; MacKenzie, F. T.


    For almost a century, it has been recognized that the present-day thickness and areal extent of Phanerozoic sedimentary strata increase progressively with decreasing geologic age. This pattern has been interpreted either as reflecting an increase in the rate of sedimentation toward the present (Barrell, 1917; Schuchert, 1931; Ronov, 1976) or as resulting from better preservation of the younger part of the geologic record ( Gilluly, 1949; Gregor, 1968; Garrels and Mackenzie, 1971a; Veizer and Jansen, 1979, 1985).Study of the rocks themselves led to similarly opposing conclusions. The observed secular (=age) variations in relative proportions of lithological types and in chemistry of sedimentary rocks (Daly, 1909; Vinogradov et al., 1952; Nanz, 1953; Engel, 1963; Strakhov, 1964, 1969; Ronov, 1964, 1982) were mostly given an evolutionary interpretation. An opposing, uniformitarian, approach was proposed by Garrels and Mackenzie (1971a). For most isotopes, the consensus favors deviations from the present-day steady state as the likely cause of secular trends.This chapter attempts to show that recycling and evolution are not opposing, but complementary, concepts. It will concentrate on the lithological and chemical attributes of sediments, but not deal with the evolution of sedimentary mineral deposits (Veizer et al., 1989) and of life ( Sepkoski, 1989), both well amenable to the outlined conceptual treatment. The chapter relies heavily on Veizer (1988a) for the sections dealing with general recycling concepts, on Veizer (2003) for the discussion of isotopic evolution of seawater, and on Morse and Mackenzie (1990) and Mackenzie and Morse (1992) for discussion of carbonate rock recycling and environmental attributes.

  11. School-Based Strategies to Reduce Suicidal Ideation, Suicide Attempts, and Discrimination among Sexual Minority and Heterosexual Adolescents in Western Canada


    Saewyc, Elizabeth M.; Konishi, Chiaki; Rose, Hilary A.; Homma, Yuko


    This study explored the relationships between the existence of and length of time since implementation of school-based Gay-Straight Alliances (GSAs) and explicit anti-homophobic bullying policies in secondary schools across British Columbia, Canada, with experiences of anti-gay discrimination, suicidal ideation and attempts among lesbian, gay, bisexual (LGB), mostly heterosexual, and exclusively heterosexual students. Analyses of the province-wide random cluster-stratified 2008 B.C. Adolescen...

  12. Uranium favorability of tertiary sedimentary rocks of the western Okanogan highlands and of the upper Columbia River valley, Washington. [Measurement and sampling of surface sections, collection of samples from isolated outcrops, and chemical and mineralogical analyses of samples; no known uranium deposits

    Energy Technology Data Exchange (ETDEWEB)

    Marjaniemi, D.K.; Robins, J.W.


    Tertiary sedimentary rocks in the northern portions of the western Okanogan highlands and in the upper Columbia River valley were investigated during a regional study to determine the favorability for potential uranium resources of the Tertiary sedimentary rocks of northeastern Washington. This project involved measurement and sampling of surface sections, collection of samples from isolated outcrops, and chemical and mineralogical analyses of samples. No portion of the project area of this report is rated of high or of medium favorability for potential uranium resources. Low favorability ratings are given to Oroville, Tonasket, and Pine Creek areas of the Okanogan River valley; to the Republic graben; and to the William Lakes, Colville, and Sheep Creek areas of the upper Columbia River valley. All these areas contain some fluvial, poorly sorted feldspathic or arkosic sandstones and conglomerates. These rocks are characterized by very low permeability and a consistently high siliceous matrix suggesting very low initial permeability. There are no known uranium deposits in any of these areas, and low level uranium anomalies are rare.

  13. The Registry and Follow-Up of Complex Pediatric Therapies Program of Western Canada: A Mechanism for Service, Audit, and Research after Life-Saving Therapies for Young Children

    Directory of Open Access Journals (Sweden)

    Charlene M. T. Robertson


    Full Text Available Newly emerging health technologies are being developed to care for children with complex cardiac defects. Neurodevelopmental and childhood school-related outcomes are of great interest to parents of children receiving this care, care providers, and healthcare administrators. Since the 1970s, neonatal follow-up clinics have provided service, audit, and research for preterm infants as care for these at-risk children evolved. We have chosen to present for this issue the mechanism for longitudinal follow-up of survivors that we have developed for western Canada patterned after neonatal follow-up. Our program provides registration for young children receiving complex cardiac surgery, heart transplantation, ventricular assist device support, and extracorporeal life support among others. The program includes multidisciplinary assessments with appropriate neurodevelopmental intervention, active quality improvement evaluations, and outcomes research. Through this mechanism, consistently high (96% follow-up over two years is maintained.

  14. Sedimentary condensation and authigenesis (United States)

    Föllmi, Karl


    Most marine authigenic minerals form in sediments, which are subjected to condensation. Condensation processes lead to the formation of well individualized, extremely thin ( 100ky), and which experienced authigenesis and the precipitation of glaucony, verdine, phosphate, iron and manganese oxyhydroxides, iron sulfide, carbonate and/or silica. They usually show complex internal stratigraphies, which result from an interplay of sediment accumulation, halts in sedimentation, sediment winnowing, erosion, reworking and bypass. They may include amalgamated faunas of different origin and age. Hardgrounds may be part of condensed beds and may embody strongly condensed beds by themselves. Sedimentary condensation is the result of a hydrodynamically active depositional regime, in which sediment accumulation, winnowing, erosion, reworking and bypass are processes, which alternate as a function of changes in the location and intensity of currents, and/or as the result of episodic high-energy events engendered by storms and gravity flow. Sedimentary condensation has been and still is a widespread phenomenon in past and present-day oceans. The present-day distribution of glaucony and verdine-rich sediments on shelves and upper slopes, phosphate-rich sediments and phosphorite on outer shelves and upper slopes, ferromanganese crusts on slopes, seamounts and submarine plateaus, and ferromanganese nodules on abyssal seafloors is a good indication of the importance of condensation processes today. In the past, we may add the occurrence of oolitic ironstone, carbonate hardgrounds, and eventually also silica layers in banded iron formations as indicators of the importance of condensation processes. Besides their economic value, condensed sediments are useful both as a carrier of geochemical proxies of paleoceanographic and paleoenvironmental change, as well as the product of episodes of paleoceanographic and paleoenvironmental change themselves.

  15. The Year Without a Ski Season: An Analysis of the Winter of 2015 for Three Ski Resorts in Western Canada Using Historical and Simulation Model Forecasted Climate Data (United States)

    Pidwirny, M. J.; Goode, J. D.; Pedersen, S.


    The winter of 2015 will go down as "the year without a ski season" for many ski resorts located close to the west coast of Canada and the USA. During this winter season, a large area of the eastern North Pacific Ocean had extremely high sea surface temperatures. These high sea surface temperatures influenced weather patterns on the west coast of North America producing very mild temperatures inland. Further, in alpine environments precipitation that normally arrives in the form of snow instead fell as rain. This research examines the climate characteristics of the winter of 2015 in greater detail for three ski resorts in British Columbia, Canada: Mount Washington, Cypress Mountain and Hemlock Valley. For these resorts, historical (1901 to 2013) and IPCC AR5 climate model forecasted climate data (RCP8.5 for 2025, 2055, and 2085) was generated for the variable winter degree days < 0°C (a measure of winter season coldness) using the spatially interpolated climate database ClimateBC. A value for winter degree days < 0°C was also estimated from recorded climate data at nearby meteorological stations for comparative analysis. For all three resorts, the winter of 2015 proved to be warmer than any individual year in the period 1901 to 2013. Interpolations involving the multi-model ensemble forecast means suggest that the climate associated with winter of 2015 will become the average normal for these resorts in only 35 to 45 years under the RCP8.5 emission scenario.

  16. Comment by J.P. Figueiredo, & Hoorn, C. on 'Late Miocene sedimentary environments in south-western Amazonia (Solimões Formation; Brazil)' by Martin Gross, Werner E. Piller, Maria Ines Ramos, Jackson Douglas da Silva Paz (United States)

    Figueiredo, Jorge Jesus Picanço


    In their paper Gross et al., 2011 present an excellent description of a series of outcrops from the Eirunepe region in western Amazonia (Brazil). The authors interpret these sediments as relics of a Late Miocene anastomosing fluvial system and conclude that the paleogeography of the entire western Amazon region must have been characterized by this environmental setting. They also imply that therefore a long-lived lake system - or megawetland - never existed. We contend this assumption for some reasons, amongst them, the most important are: (1) this is an inconsistent overgeneralized conclusion; (2) The authors make references to previous scientific works we published which we consider incorrect, and therefore can mislead their readers.

  17. Geochemistry and geochronology from Cretaceous magmatic and sedimentary rocks at 6°35‧ N, western flank of the Central cordillera (Colombian Andes): Magmatic record of arc growth and collision (United States)

    Jaramillo, J. S.; Cardona, A.; León, S.; Valencia, V.; Vinasco, C.


    The spatio-temporal, compositional and deformational record of magmatic arcs are sensible markers of the long-term evolution of convergent margins including collisional events. In this contribution, field relations, U-Pb LA-ICP-MS zircon geochronology from magmatic and sedimentary rocks, and whole-rock geochemistry from volcanic and plutonic rocks are used to reconstruct the Cretaceous arc growth and collision in the awakening of the Northern Andean orogeny in northwestern Colombia. The Quebradagrande Complex that includes a sequence of volcanic rocks intercalated with quartz-rich sediments is a tholeiitic arc characterized by an enrichment in LREE and Nb-Ti anomalies that document crustal thickening in an arc system that was already active by ca. 93 Ma. This arc was built associated with thin continental and newly formed oceanic crust, as suggested by the presence of Triassic and older detrital zircons in the associated sandstones. This fringing arc subsequently experienced deformation and a major switch to and enriched calc-alkaline high-k plutonism between 70 and 73 Ma. The deformation record and changes in composition are related to an opposite double-vergence Molucca-sea type arc-arc collision that ended with the accretion to the continental margin of an allochthonous island arc built on an oceanic plateau associated with the Caribbean plate. The new time-framework suggest that the Late Cretaceous to Paleocene collisional tectonics include various stages before the switching to a subduction-dominated regime in most of the Cenozoic.

  18. Submarine Landslides in Arctic Sedimentation: Canada Basin (United States)

    Mosher, David C.; Shimeld, John; Hutchinson, Deborah R.; Lebedova-Ivanova, N; Chapman, C.


    Canada Basin of the Arctic Ocean is the least studied ocean basin in the World. Marine seismic field programs were conducted over the past 6 years using Canadian and American icebreakers. These expeditions acquired more than 14,000 line-km of multibeam bathymetric and multi-channel seismic reflection data over abyssal plain, continental rise and slope regions of Canada Basin; areas where little or no seismic reflection data existed previously. Canada Basin is a turbidite-filled basin with flat-lying reflections correlateable over 100s of km. For the upper half of the sedimentary succession, evidence of sedimentary processes other than turbidity current deposition is rare. The Canadian Archipelago and Beaufort Sea margins host stacked mass transport deposits from which many of these turbidites appear to derive. The stratigraphic succession of the MacKenzie River fan is dominated by mass transport deposits; one such complex is in excess of 132,000 km2 in area and underlies much of the southern abyssal plain. The modern seafloor is also scarred with escarpments and mass failure deposits; evidence that submarine landsliding is an ongoing process. In its latest phase of development, Canada Basin is geomorphologically confined with stable oceanographic structure, resulting in restricted depositional/reworking processes. The sedimentary record, therefore, underscores the significance of mass-transport processes in providing sediments to oceanic abyssal plains as few other basins are able to do.

  19. School-Based Strategies to Reduce Suicidal Ideation, Suicide Attempts, and Discrimination among Sexual Minority and Heterosexual Adolescents in Western Canada. (United States)

    Saewyc, Elizabeth M; Konishi, Chiaki; Rose, Hilary A; Homma, Yuko


    This study explored the relationships between the existence of and length of time since implementation of school-based Gay-Straight Alliances (GSAs) and explicit anti-homophobic bullying policies in secondary schools across British Columbia, Canada, with experiences of anti-gay discrimination, suicidal ideation and attempts among lesbian, gay, bisexual (LGB), mostly heterosexual, and exclusively heterosexual students. Analyses of the province-wide random cluster-stratified 2008 B.C. Adolescent Health Survey (n =21,70 8) compared students in schools with GSAs or policies implemented at least 3 years, and less than 3 years, with those in schools without GSAs or anti-homophobia policies, using multinomial logistic regression, separately by gender. LGB students had lower odds of past year discrimination, suicidal thoughts and attempts, mostly when policies and GSAs had been in place for 3+ years; policies had a less consistent effect than GSAs. Heterosexual boys, but not girls, also had lower odds of suicidal ideation and attempts in schools with longer-established anti-homophobic bullying policies and GSAs. Given consistently higher documented risk for suicidal ideation and attempts among LGB and mostly heterosexual adolescents, prevention efforts should be a priority, and school-level interventions, such as GSAs, may be an effective approach to reducing this risk, while also offering prevention benefits for heterosexual boys.

  20. Detailed Sedimentary Facies of the 8th Member of Shihezi Formation in the Block S47 in Western Sulige Gas Field%苏里格气田西区 S47区块石盒子组八段沉积微相

    Institute of Scientific and Technical Information of China (English)

    王振国; 杨仁超; 路中奇; 赵忠军; 崔明明; 远义飞


    鄂尔多斯盆地苏里格气田是我国陆上产能最大的气田,其主力产气层---二叠纪石盒子群八段岩性致密,储层的分布主要受沉积微相控制。但S47区块作为苏里格气田西区一个重要的新区,有关沉积微相的认识仍存在分歧。在岩心观察、钻井资料及样品分析的基础上,重点研究了S47区块盒8段沉积微相,认为该区盒8段属辫状河三角洲前缘沉积,并识别出水下分流河道、河口坝、席状砂、水下天然堤、分流间湾等5种微相;最有利的储集砂体主要为水下分流河道叠置砂体,其次为河口坝砂体。沉积微相及其展布特征的新认识为该区储层预测、水平井整体开发提供了地质理论依据。%Sulige gas field in Ordos basin is the largest terrestrial gas production field in China .As a typical tight sandstone gas pool , distribution of reservoirs of the main gas -producing strata in Sulige gas field---the 8th mem-ber of Shihezi formation in Permian system (P2h8 for short), is mainly controlled by detailed sedimentary facies .But disagreements about detailed sedimentary facies still exist in the Block S 47---an important new region in the west-ern part of Sulige gas field .Detailed sedimentary facies of P 2h8 in the Block S47 were studied on the basis of drilling core observation , analysis of well logs and samples .It is considered that the strata of P 2h8 in the Block S47 was de-posited in braided delta front , which can be further sub -divided into subaqueous distributary channel , estuary bar , sand sheet , subaqueous levee and interdistributary bay etc .5 detailed sedimentary facies .The most favorable reser-voir is subaqueous distributary channel overlaid sand bodies and estuary bar sand bodies secondarily .New under-standings on detailed sedimentary facies and distribution features provide theoretical foundations for reservoir predic -tion and integrated exploitation by horizontal wells in the Block

  1. Application of boreal forest toxicity data in the decision-making process for contaminated soil clean-up remediation at oil and gas fields in Western Canada

    Energy Technology Data Exchange (ETDEWEB)

    Scroggins, R.; Princz, J. [Environment Canada, Ottawa, ON (Canada); Moody, M. [Saskatchewan Research Council, Regina, SK (Canada); Olsgard-Dumanski, M.; Haderlein, L. [WorleyParsons Canada, Calgary, AB (Canada); Moore, B. [Devon Canada Corp., Calgary, AB (Canada)


    This presentation reported on a multi-year research project in which a broad range of boreal forest test methods for assessing petroleum hydrocarbon (PHC) toxicity in contaminated soil were used to show that clean-up decisions can be made on a field-wide basis through focused biological testing of typical drill sump and flare pit locations within an oil and gas field. Remediation at most sites will likely be limited to the Alberta soil eco-contact guidelines for PHC F2 and F3 fractions. Since Tier 1 eco-contact guidelines are derived using toxicity data from fresh crude and using agricultural plant species, it was more logical to follow a Tier 2 eco-contact pathway approach because most contamination was related to drilling sumps and flare pits containing highly weathered PHCs and species native to the boreal eco-zone of Canada. The site-specific remedial objective (SSRO) option within the Tier 2 guideline was used because of the large number of sites requiring remediation, and the similarity of sites within pre-determined Risk Assessment Zones. For representative contaminated soils, a SSRO was derived from the twenty-fifth percentile of the estimated species sensitivity distribution of all acceptable boreal plant, earthworm, springtail and mite test endpoints. The purpose of the project was to reduce soil volumes sent to landfill during site remediation by showing that residual impacts from weathered PHC in soil do not have damaging effects on boreal forest receptors following remediation. Data was included to show the value of this approach and the variability between sites and their effect on regionalizing a Tier 2 eco-contact guideline.

  2. 柴达木盆地西部地区新生代演化特征与青藏高原隆升%Cenozoic Uplift of the Tibetan Plateau: Evidence from tectonic-sedimentary evolution of the Western Qaidam Basin

    Institute of Scientific and Technical Information of China (English)

    王亚东; 张涛; 迟云平; 刘艳蕊; 张志高; 李仕远; 方小敏; 张跃中


    通过对柴达木盆地西部地区(柴西地区)地震剖面构造-沉积相演化的分析,结合基底岩性及区域构造运动历史,重建了柴西地区新生代构造-沉积动态演化框架.柴西地区新生代以来一直处在印欧板块碰撞所引起的青藏高原阶段性隆升的挤压构造背景下,经历了两大构造变形期:第一变形期主要发育在古近纪,变形高峰在下干柴沟组上段,第二变形期发育在新近纪-第四纪,变形强度日益加剧.剖面沉积相的变化体现柴西地区经历了水进-静水沉降-水退的过程,平面沉积相演变是沉积中心受构造运动控制的直接结果;受构造演化控制柴西地区以Ⅺ号(油狮断裂)和油北断裂为分界线,由南至北地表形态表现为3种不同样式:柴西南区断裂发育,柴西中部为英雄岭新生造山带,柴西北区主要发育冲断褶皱.柴西地区构造-沉积演化特征是对青藏高原阶隆升的响应,同时记录了青藏高原向北间歇性蔓延生长的过程.%on the basis of the analysis of structure and sedimentary evolution of the seismic section in Western Qaidam Basin and combining the basement lithology, faults distribution and history of tectonic movement, we reconstructed the dynamical evolution framework of structure and sedimentation of Western Qaidam Basin during the Cenozoic. Our results suggested that Western Qaidam Basin was under the compression tectonicbackground of the Tibetan Plateau uplift caused by the collision of India and Eurasia in the Cenozoic and underwent two violent periods of tectonic deformation. The Western Qaidam Basin had undergone two periods of tectonic deformation. The first ocurred in the Paleocene, and reached the peak at the E23; the second was in the Neocene-Quaternary, and the deformation intensified rapidly. The forces transmitted from the south to the north,while the tectonic deformation spread from the west to the east, which indicated that the thrust of the

  3. Geothermal resources of California sedimentary basins (United States)

    Williams, C.F.; Grubb, F.V.; Galanis, S.P.


    The 2004 Department of Energy (DOE) Strategic Plan for geothermal energy calls for expanding the geothermal resource base of the United States to 40,000 MW of electric power generating potential. This will require advances in technologies for exploiting unconventional geothermal resources, including Enhanced Geothermal Systems (EGS) and geopressured geothermal. An investigation of thermal conditions in California sedimentary basins through new temperature and heat flow measurements reveals significant geothermal potential in some areas. In many of the basins, the combined cooling effects of recent tectonic and sedimentary processes result in relatively low (geothermal gradients. For example, temperatures in the upper 3 km of San Joaquin, Sacramento and Ventura basins are typically less than 125??C and do not reach 200??c by 5 km. By contrast, in the Cuyama, Santa Maria and western Los Angeles basins, heat flow exceeds 80 mW/m2 and temperatures near or above 200??C occur at 4 to 5 km depth, which represents thermal conditions equivalent to or hotter than those encountered at the Soultz EGS geothermal site in Europe. Although the extractable geothermal energy contained in these basins is not large relative to the major California producing geothermal fields at The Geysers or Salton Sea, the collocation in the Los Angeles basin of a substantial petroleum extraction infrastructure and a major metropolitan area may make it attractive for eventual geothermal development as EGS technology matures.

  4. Paleoceanographic events in cretaceous petroleum basins, offshore mid-Norway of SE Saskatchewan, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Gradstein, F.M.; Saether, T.; Nystuen, J.P.; Backstrom, S.A. [Saga Petroleum A/S, Forus (Norway)


    During the Cretaceous period, the narrow, longitudinal seaways between Greenland and Norway received a large volume of fine-grained siliciclast sediments with intercalated gravity-flow sandstone wedges. The sedimentary succession may be subdivided into four broad units: (1) thin and mostly oxic, marly sediments, (2) dark, dysaerobic mudstones and minor sands, (3) thick mudstone facies with thin slope-apron turbidite sands, and (4) grayish laminated mudstones with local sands in the northern area. A widespread Barremian-Aptian hiatus may be linked to Atlantic rift-onset unconformities recognized offshore eastern Canada. Around the lower-upper Cretaceous boundary, watermass conditions changed from dysaerobic to oxic, an event also reported from central and western Europe.

  5. Western Canadian coalbed methane gas activity chart 2003

    Energy Technology Data Exchange (ETDEWEB)



    This geological map of major coal-bearing formations in western Canada identifies various coal basins in British Columbia, Alberta, and Saskatchewan along with their associated coal rank and land area. The map identifies coalbed methane projects underway as well as coalbed methane pilot projects in the Western Canada Sedimentary Basin (WCSB), and provides estimates for coal resources in-place (in billion tons), and coalbed gas-in-place (in trillion cubic feet). The ages of the coal-bearing formations range from Tertiary, Lower Cretaceous, Upper Cretaceous, and Upper Cretaceous-Tertiary. The major regions in British Columbia include the Insular coal fields, the Intermontane belt coal fields, the Northeast foothills and plains, and Southeast foothills. The following Calgary-based companies placed their advertisements on the map with highlights of the services they provide relating to coalbed methane development: Schlumberger, Sanjel, Fekete Associates, GrenCo Industries, Weatherford Underbalanced Systems, Weatherford Artificial Lift Systems, Toromont Process Systems, Pinnacle Technology, Enerflex, Sproule, Trident Exploration Corp., Perspective Consultants Inc., Halliburton Energy Services, Computer Modeling Group, Kudu Industries Inc., and CalFrac Well Services. Advertisement from Edmonton-based C-Fer Technologies, and the Toronto-based Canadian Institute Energy Group were also included on the map. 1 fig.

  6. Atlantic Canada's gas industry overview

    Energy Technology Data Exchange (ETDEWEB)

    Gill, G. [Emera Energy Inc., Halifax, NS (Canada)


    Emera Energy is a vertically integrated energy company with 4 billion dollars in assets, and one billion dollars in revenue. The ownership structure of Emera Energy was reviewed. The major issues facing Emera Energy all imply a balancing act, between end users and producers, government and industry, infrastructure owners and customers, and Canada versus exports. A brief overview of the regulatory environment in New Brunswick and Nova Scotia was presented. Some of the other issues addressed in this presentation were: project Think, Maritime fragmentation and parochialism, federal/provincial equalization payments, fishing/petroleum industry clash, sovereign risk higher than need be, immature energy industry in Atlantic Canada, and offshore exploration and production industry different than that of the Western Canada Sedimentary Basin (WCSB). National Energy Board (NEB) gas export hearing into the appropriateness of the market oriented export liberalization rules implemented in 1987 for exports of Atlantic Canada gas production is being challenged by the government of New Brunswick. Figures depicting the Canadian gas resource and Nova Scotia offshore gas development were presented, followed by a table providing East Coast offshore costs. The Sable Offshore Energy Project was described, as well as the Deep Panuke gas field. An update on offshore exploration was provided, including comments on onshore activity concerning coal bed methane. A status report of the natural gas supply contracts was discussed. Conventional gas was the next topic discussed, beginning with an overview of onshore activity. The midstream sector was reviewed, with a brief discussion about the existing pipeline system. The mainline expansion plans were reviewed. Some of the gas transmission issues facing the industry in Atlantic Canada are high transport rates, postage stamp toll that is anti-Canadian, gate keeper role for producers, and onerous rules and poor customer service. The Cartier pipeline

  7. Development of the Mozambique and Ruvuma sedimentary basins, offshore Mozambique (United States)

    Salman, G.; Abdula, I.


    Two major sedimentary basins have been identified on the continental margin of Mozambique—Mozambique Basin and Ruvuma Basin. The formation of the basins is related to the break-up of Gondwana and opening of the western part of the Indian Ocean. The basins are relatively young, having developed discordantly to the structural plan of Gondwana sedimentary basins. The history of the formation of the East African continental margin sedimentary basins within Mozambique has been studied on the basis of the present-day concept of Gondwana break-up and Madagascar's drift with respect to Africa. Two stages in the history of the East African basins can be recognized: late-Gondwana and post-Gondwana. The late-Gondwana stage (303-157 Ma) is typified by sedimentary and volcanogenic rocks of the Karoo Group. The post-Gondwana stage (157-0 Ma) corresponds to the period of active Gondwana break-up and the formation of Indian Ocean marginal basins. The Mozambique Basin occupies both central and southern parts of the coastal plain of Mozambique, extending onto the continental shelf and slope. The sedimentary fill is composed of Upper Jurassic, Cretaceous and Cenozoic rocks which discordantly overly the Karoo basalts. The Upper Jurassic occurs as continental red-beds, mostly distributed within buried grabens. Cretaceous rocks occur as terrigenous sediments of continental and marine genesis. Cenozoic deposits are of predominantly marine and deltaic origin. The Ruvuma Basin, situated in the north of Mozambique, is part of an extended East African marginal basin which includes parts of the coastal plains and continental margins of Tanzania and Kenya. The basement of the basin is composed of crystalline and metamorphic rocks of pre-Cambrian age. The sedimentary fill is represented by continental terrigenous Karoo sediments, marine and lagoonal Jurassic deposits, and marine and deltaic rocks of Cretaceous and Cenozoic age. The main difference between the sedimentary fill of the

  8. Quantitative characterisation of sedimentary grains (United States)

    Tunwal, Mohit; Mulchrone, Kieran F.; Meere, Patrick A.


    Analysis of sedimentary texture helps in determining the formation, transportation and deposition processes of sedimentary rocks. Grain size analysis is traditionally quantitative, whereas grain shape analysis is largely qualitative. A semi-automated approach to quantitatively analyse shape and size of sand sized sedimentary grains is presented. Grain boundaries are manually traced from thin section microphotographs in the case of lithified samples and are automatically identified in the case of loose sediments. Shape and size paramters can then be estimated using a software package written on the Mathematica platform. While automated methodology already exists for loose sediment analysis, the available techniques for the case of lithified samples are limited to cases of high definition thin section microphotographs showing clear contrast between framework grains and matrix. Along with the size of grain, shape parameters such as roundness, angularity, circularity, irregularity and fractal dimension are measured. A new grain shape parameter developed using Fourier descriptors has also been developed. To test this new approach theoretical examples were analysed and produce high quality results supporting the accuracy of the algorithm. Furthermore sandstone samples from known aeolian and fluvial environments from the Dingle Basin, County Kerry, Ireland were collected and analysed. Modern loose sediments from glacial till from County Cork, Ireland and aeolian sediments from Rajasthan, India have also been collected and analysed. A graphical summary of the data is presented and allows for quantitative distinction between samples extracted from different sedimentary environments.

  9. [History of trachoma in canada]. (United States)

    Milot, Jean


    The author retraces the history of trachoma in Canada. The numerous articles in Canadian medical journals from the middle of the 18th to the middle of the 19th century show the remarkable contribution of Canadian ophthalmologists. The clinical symptoms and signs followed by the etiology and the different modes of treatment are reviewed. The presence and prevention of trachoma in Canada, ranging from Montreal to Toronto, also in Halifax with the arrival of the transatlantic immigrants, as well as those reaching the western provinces of Canada are described. How the Canadian Department of Health belatedly introduced a prevention campaign only after a widespread dissemination of trachoma across the country is also examined.

  10. Western Canada study of animal health effects associated with exposure to emissions from oil and natural gas field facilities. Study design and data collection III. Methods of assessing animal exposure to contaminants from the oil and gas industry. (United States)

    Waldner, Cheryl L


    Researchers measured exposure to oil and gas industry emissions in 205 cow-calf herds located in Western Canada. They measured airborne concentrations of sulfur dioxide, hydrogen sulfide, and volatile organic compounds with passive monitors placed in each pasture, wintering, or calving area that contained study animals from the start of the breeding season in the spring of 2001 until June 30, 2002. Researchers continued air monitoring in a subset of herds to the end of the study in fall 2002. Each sampling device was exposed for 1 month and then shipped to the laboratory for analysis. New samplers were installed and the shelters relocated, as necessary, to follow the movements of herd-management groups between pastures. Researchers linked the results of the air-monitoring analysis to individual animals for the relevant month. For the 205 herds examined at pregnancy testing in 2001, monthly mean exposures on the basis of all available data were as follows: sulfur dioxide, geometric mean (GM)=0.5 ppb, geometric standard deviation (GSD)=2.2; hydrogen sulfide, GM=0.14 ppb, GSD=2.3; benzene, GM=0.247 microg/m3, GSD=2.5; and toluene, GM=0.236 microg/m3, GSD=2.7. Benzene and toluene were surrogates for volatile organic compound exposure. In addition to passive measurements of air quality, researchers obtained data from provincial regulatory agencies on the density of oil and gas field facilities and on flaring and venting from the surrounding facilities. They developed the data into additional measures of exposure that were linked to each animal at each location for each month of the study.

  11. A cross-sectional study examining the prevalence and risk factors for anti-microbial-resistant generic Escherichia coli in domestic dogs that frequent dog parks in three cities in south-western Ontario, Canada. (United States)

    Procter, T D; Pearl, D L; Finley, R L; Leonard, E K; Janecko, N; Reid-Smith, R J; Weese, J S; Peregrine, A S; Sargeant, J M


    Anti-microbial resistance can threaten health by limiting treatment options and increasing the risk of hospitalization and severity of infection. Companion animals can shed anti-microbial-resistant bacteria that may result in the exposure of other dogs and humans to anti-microbial-resistant genes. The prevalence of anti-microbial-resistant generic Escherichia coli in the faeces of dogs that visited dog parks in south-western Ontario was examined and risk factors for shedding anti-microbial-resistant generic E. coli identified. From May to August 2009, canine faecal samples were collected at ten dog parks in three cities in south-western Ontario, Canada. Owners completed a questionnaire related to pet characteristics and management factors including recent treatment with antibiotics. Faecal samples were collected from 251 dogs, and 189 surveys were completed. Generic E. coli was isolated from 237 of the faecal samples, and up to three isolates per sample were tested for anti-microbial susceptibility. Eighty-nine percent of isolates were pan-susceptible; 82.3% of dogs shed isolates that were pan-susceptible. Multiclass resistance was detected in 7.2% of the isolates from 10.1% of the dogs. Based on multilevel multivariable logistic regression, a risk factor for the shedding of generic E. coli resistant to ampicillin was attending dog day care. Risk factors for the shedding of E. coli resistant to at least one anti-microbial included attending dog day care and being a large mixed breed dog, whereas consumption of commercial dry and home cooked diets was protective factor. In a multilevel multivariable model for the shedding of multiclass-resistant E. coli, exposure to compost and being a large mixed breed dog were risk factors, while consumption of a commercial dry diet was a sparing factor. Pet dogs are a potential reservoir of anti-microbial-resistant generic E. coli; some dog characteristics and management factors are associated with the prevalence of anti

  12. Preliminary Rock Physics Characterization of Mississippian Carbonate Reservoir in Canada (United States)

    Lee, M.; Keehm, Y.; Kim, H.


    The Mississippian formations in the Western Canada Sedimentary Basin are known to have large hydrocarbon resources. The Lodgepole formation is the most important reservoir for oil production in Daly and Virden fields. In this study, we performed preliminary reservoir characterization using rock physics modeling. We first delineated the Lodgepole formation by geological information, well-logs and core analysis data. Then, we conducted rock physics analyses such as GR-AI, DEM modeling, porosity-Vp, density-Vp, and porosity-permeability. We identified the Lodgepole formation has different porosity types, volume of shale, and the degree of fractures in difference intervals. In the upper part of the formation, we found that vuggy pores are well developed. Inter-particular porosity and fractures become significant as the depth increases. We found that the lower part can be divided into two groups by acoustic impedance. The prospective reservoir interval, one of the two groups, has higher fracture density, which can be identified by lower acoustic impedance. This result also implies that we could also use AVO analyses to delineate good reservoir intervals. In conclusion, rock physics modeling can be effectively applied to characterize the Lodgepole formation quantitatively with well-log and core analysis data. Acknowledgement: This work was supported by the Energy Resources R&D program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Knowledge Economy (No. 2009201030001A).

  13. Canada acute coronary syndrome score was a stronger baseline predictor than age ≥75 years of in-hospital mortality in acute coronary syndrome patients in western Romania

    Directory of Open Access Journals (Sweden)

    Pogorevici A


    Full Text Available Antoanela Pogorevici, Ioana Mihaela Citu, Diana Aurora Bordejevic, Florina Caruntu, Mirela Cleopatra TomescuCardiology Department, “Victor Babes” University of Medicine and Pharmacy, Timisoara, RomaniaBackground: Several risk scores were developed for acute coronary syndrome (ACS patients, but their use is limited by their complexity.Purpose: The purpose of this study was to identify predictors at admission for in-hospital mortality in ACS patients in western Romania, using a simple risk-assessment tool – the new Canada acute coronary syndrome (C-ACS risk score.Patients and methods: The baseline risk of patients admitted with ACS was retrospectively assessed using the C-ACS risk score. The score ranged from 0 to 4; 1 point was assigned for the presence of each of the following parameters: age ≥75 years, Killip class >1, systolic blood pressure <100 mmHg, and heart rate >100 bpm.Results: A total of 960 patients with ACS were included, 409 (43% with ST-segment elevation myocardial infarction (STEMI and 551 (57% with non-ST-segment elevation acute coronary syndrome (NSTE-ACS. The C-ACS score predicted in-hospital mortality in all ACS patients with a C-statistic of 0.95 (95% CI: 0.93–0.96, in STEMI patients with a C-statistic of 0.92 (95% confidence interval [CI]: 0.89–0.94, and in NSTE-ACS patients with a C-statistic of 0.97 (95% CI: 0.95–0.98. Of the 960 patients, 218 (22.7% were aged ≥75 years. The proportion of patients aged ≥75 years was 21.7% in the STEMI subgroup and 23.4% in the NSTE-ACS subgroup (P>0.05. Age ≥75 years was significantly associated with in-hospital mortality in ACS patients (odds ratio [OR]: 3.25, 95% CI: 1.24–8.25 and in the STEMI subgroup (OR >3.99, 95% CI: 1.28–12.44. Female sex was strongly associated with mortality in the NSTE-ACS subgroup (OR: 27.72, 95% CI: 1.83–39.99.Conclusion: We conclude that C-ACS score was the strongest predictor of in-hospital mortality in all ACS patients while

  14. Regional stratospheric warmings in the Pacific-Western Canada (PWC sector during winter 2004/2005: implications for temperatures, winds, chemical constituents and the characterization of the Polar vortex

    Directory of Open Access Journals (Sweden)

    A. H. Manson


    Full Text Available The vortex during winter 2004/2005 was interesting for several reasons. It has been described as "cold" stratospherically, with relatively strong westerly winds. Losses of ozone until the final warming in March were considerable, and comparable to the cold 1999–2000 winter. There were also modest warming events, indicated by peaks in 10 hPa zonal mean temperatures at high latitudes, near 1 January and 1 February. Events associated with a significant regional stratospheric warming in the Pacific-Western Canada (PWC sector then began and peaked toward the end of February, providing strong longitudinal variations in dynamical characteristics (Chshyolkova et al., 2007; hereafter C07. The associated disturbed vortex of 25 February was displaced from the pole and either elongated (upper or split into two cyclonic centres (lower.

    Observations from Microwave Limb Sounder (MLS on Aura are used here to study the thermal characteristics of the stratosphere in the Canadian-US (253° E and Scandinavian-Europe (16° E sectors. Undisturbed high latitude stratopause (55 km zonal mean temperatures during the mid-winter (December–February reached 270 K, warmer than empirical-models such as CIRA-86, suggesting that seasonal polar warming due to dynamical influences affects the high altitude stratosphere as well as the mesosphere. There were also significant stratopause differences between Scandinavia and Canada during the warming events of 1 January and 1 February, with higher temperatures near 275 K at 16° E. During the 25 February "PWC" event a warming occurred at low and middle stratospheric heights (10–30 km: 220 K at 253° E and the stratopause cooled; while over Scandinavia-Europe the stratosphere below ~30 km was relatively cold at 195 K and the stratopause became even warmer (>295 K and lower (~45 km. The zonal winds followed the associated temperature gradients so that the vertical and latitudinal gradients of the winds differed strongly

  15. Biology of nesting Aleutian Canada goose, summer 1975 (United States)

    US Fish and Wildlife Service, Department of the Interior — In 1974 and 1975 breeding Aleutian Canada geese, Branta canadensis leucopareia, were studied at Buldir Island, western Aleutian Islands. Buldir is the only known...

  16. Limitations On Canada Goose Production at Fish springs National Wildlife Refuge, Utah (United States)

    US Fish and Wildlife Service, Department of the Interior — We studied the western Canada goose (B. c. moffitti) population at Fish Springs National Wildlife Refuge in western Utah from March to July in 1996 and 1997 to...

  17. Canada`s oceans: Experiences and practices

    Energy Technology Data Exchange (ETDEWEB)



    Canada has the world`s longest coastline. In recent years, growth in Canada`s oceans sector has resulted in increased pressures on the ocean environment. In many areas the biodiversity and ecological integrity of marine ecosystems are being threatened. There is a need to proactively conserve, restore, and protect marine ecosystem functions, species, and habitats for future generations. This document provides an overview of the economic contributions of the oceans sector to Canada`s Gross Domestic Product (GDP), explains Canada`s oceans management strategy, the national system of marine protected areas, and programs of action for the protection of the marine environment from land-based activities. The broad objectives of Canada`s Policy for the Management of Fish Habitat, the Canadian Biodiversity Strategy, and the Program of Living Marine Resource Management are reviewed. Harmonization of Canada`s shipping policy and its marine safety and environmental policies with international maritime laws are discussed, along with offshore energy and mineral resource development, and the integral role that oceans play in the earth`s climate. Oceans management and development assistance provided by Canada through the Canadian International Development Agency and the International Development Research Centre, especially in the areas of management of the uses of the ocean and seabed, protection of the marine environment, and fisheries management and development are also highlighted. Establishing a framework for sustainable ocean development, an ocean policy and related law, and further development of the knowledge bases in fisheries and marine science are some of the other priorities of CIDA`s oceans-related programs. 21 refs.

  18. Seismic stratigraphy and sedimentary architecture of the Chalk Group in south-west Denmark

    DEFF Research Database (Denmark)

    Larsen, Connie; Ineson, Jon; Boldreel, Lars Ole


    The article focuses on a study undertaken by the Chalk Group on the western onshore region of the Danish Basin in Eastern Denmark related on the seismic stratigraphy and sedimentary architecture of the region. The study is undertaken through subdividing the northern North German Basin and the south...

  19. Emerging Churches in Post-Christian Canada

    Directory of Open Access Journals (Sweden)

    Steven Studebaker


    Full Text Available The traditional mainline and evangelical churches in Canada, as in most western countries, are either in decline or static. Taken as a measure of the future, the prospects for Christianity in Canada, and more broadly the West, are bleak. Post-Christian Canada, however, contains thriving alternative and innovative forms of church, often called ‘emerging’ churches. They take many forms of expression, but share common theological convictions. Based on site research and personal interviews, this article describes the various types and contexts of these churches in Canada. It then highlights three of their central theological characteristics. First, rejecting the ‘culture wars’ social involvement of Christendom churches, they embrace practices and initiatives that transform their local communities. Second, they embrace an incarnational and contextual understanding of Christian life and ministry. Eschewing mega-church franchise models, they endeavor to shape their ministry to the their local communities. Third, they adopt a comprehensive rather than compartmental spirituality.

  20. Methylsulfone polychlorinated biphenyl and 2,2-bis(chlorophenyl)-1,1-dichloroethylene metabolites in beluga whale (Delphinapterus leucas) from the St. Lawrence River estuary and western Hudson Bay, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Letcher, R.J.; Norstrom, R.J.; Muir, D.C.G.; Sandau, C.D.; Koczanski, K.; Michaud, R.; De Guise, S.; Beland, P.


    Knowledge is limited regarding methylsulfone (MeSO{sub 2})-polychlorinated biphenyl (PCB), and especially MeSo{sub 2}-2,2-bis(chlorophenyl)-1,1-dichloroethylene (DDE), metabolites in cetacean species. The authors hypothesized that the ability of beluga whale (Delphinapterus leucas) to biotransform PCB and DDE compounds, and to form and degrade their MeSO{sub 2}-PCB and -DDE metabolites, is related to the capacity for xenobiotic metabolism. Adipose biopsies were collected from male and female beluga whale from distinct populations in the St. Lawrence River estuary (STL) and western Hudson Bay (WHB), Canada, which are contrasted by the exposure to different levels of cytochrome P450 enzyme-inducing, chlorinated hydrocarbon contaminants. The PCBs, DDTs, DDEs, 28 MeSO{sub 2} metabolites of 14 meta-para chlorine-unsubstituted PCBs, and four MeSO{sub 2} metabolites of 4,4{prime}- and 2,4{prime}-DDE were determined. The mean concentrations of total ({Sigma}-) MeSO{sub 2}-PCB in male STL beluga (230 ng/g), and ratios of {Sigma}-MeSO{sub 2}-PCB to {Sigma}-PCB (0.05) and {Sigma}-precursor-PCB (0.17) were approximately twofold higher, whereas the {Sigma}-precursor-PCB to {Sigma}-PCB ratio was approximately twofold lower, than in male WHB beluga. Both populations had a low formation capacity for MeSO{sub 2}-PCBs with {le} six chlorines (<4% of {Sigma}-MeSO{sub 2}-PCBs). The congener patterns were dominated by trichloro- and tetrachloro-MeSO{sub 2}-PCBs, and tetrachloro- and pentachloro-MeSO{sub 2}-PCBs in WHB and STL animals, respectively. In addition to 2- and 3-MeSO{sub 2}-4,4{prime}-DDE, two unknown MeSO{sub 2}-2,4{prime}-DDEs were detected. The mean 3-MeSO{sub 2}-4,4{prime}-DDE concentration in STL beluga (1.2 ng/g) was much greater than in WHB animals. The concentrations of 4,4{prime}-DDE, and not 3-MeSO{sub 2}-4,4{prime}-DDE, increased with age in male STL animals. The authors demonstrated that sulfone formation and clearance is related to metabolic capacity, and thus

  1. Modelling of reactive transport in a sedimentary basin affected by a glaciation/deglaciation event

    Energy Technology Data Exchange (ETDEWEB)

    Bea, S.A.; Mayer, U. [Univ. of British Columbia, Dept. of Earth and Ocean Sciences, Vancouver, BC (Canada); MacQuarrie, K.T.B. [Univ. of New Brunswick, Dept. of Civil Engineering, Fredericton, NB (Canada)


    Canada's plan for the long-term care of used nuclear fuel is containment and isolation in a Deep Geologic Repository (DGR) constructed in a suitable sedimentary or crystalline rock formation. In sedimentary basins fluid migration and geochemical conditions may be impacted by multiple interacting processes including density-dependent groundwater flow, solute transport, heat transfer, mechanical loading, and rock-water interactions. Understanding the interactions among these processes is important when assessing the long-term hydrodynamic and geochemical stability of sedimentary basins during glaciation/deglaciation events. To improve the capability to investigate these processes, an enhanced version of the reactive transport code MIN3P (i.e. MIN3P-NWMO) was developed and tested. The processes incorporated in the new model were evaluated by simulating reactive transport in a hypothetical sedimentary basin affected by a simplified glaciation scenario consisting of a single cycle of ice sheet advance and retreat. The simulations are used to provide an illustrative assessment of the hydrogeological and geochemical stability of this sedimentary basin over a time period of 32,500 years. The results suggest a high degree of geochemical stability. (author)

  2. Favorability for uranium in tertiary sedimentary rocks, southwestern Montana

    Energy Technology Data Exchange (ETDEWEB)

    Wopat, M A; Curry, W E; Robins, J W; Marjaniemi, D K


    Tertiary sedimentary rocks in the basins of southwestern Montana were studied to determine their favorability for potential uranium resources. Uranium in the Tertiary sedimentary rocks was probably derived from the Boulder batholith and from silicic volcanic material. The batholith contains numerous uranium occurrences and is the most favorable plutonic source for uranium in the study area. Subjective favorability categories of good, moderate, and poor, based on the number and type of favorable criteria present, were used to classify the rock sequences studied. Rocks judged to have good favorability for uranium deposits are (1) Eocene and Oligocene strata and undifferentiated Tertiary rocks in the western Three Forks basin and (2) Oligocene rocks in the Helena basin. Rocks having moderate favorability consist of (1) Eocene and Oligocene strata in the Jefferson River, Beaverhead River, and lower Ruby River basins, (2) Oligocene rocks in the Townsend and Clarkston basins, (3) Miocene and Pliocene rocks in the Upper Ruby River basin, and (4) all Tertiary sedimentary formations in the eastern Three Forks basin, and in the Grasshopper Creek, Horse Prairie, Medicine Lodge Creek, Big Sheep Creek, Deer Lodge, Big Hole River, and Bull Creek basins. The following have poor favorability: (1) the Beaverhead Conglomerate in the Red Rock and Centennial basins, (2) Eocene and Oligocene rocks in the Upper Ruby River basin, (3) Miocene and Pliocene rocks in the Townsend, Clarkston, Smith River, and Divide Creek basins, (4) Miocene through Pleistocene rocks in the Jefferson River, Beaverhead River, and Lower Ruby River basins, and (5) all Tertiary sedimentary rocks in the Boulder River, Sage Creek, Muddy Creek, Madison River, Flint Creek, Gold Creek, and Bitterroot basins.

  3. Sedimentary Characteristics and Reservoir Prediction of Paleogene in the East Part of Kuqa Foreland Basin

    Institute of Scientific and Technical Information of China (English)

    Yan Detian; Wang Hua; Wang Jiahao; Wang Qingchen


    Most of the Mesozoic and Cenozoic large-scale hydrocarbon-bearing basins in western China were formed in a similar foreland setting. Hydrocarbon exploration of the Kuqa foreland basin requires research into the sedimentary characteristics and filling evolution of the depositional sequences and their response to the basin process. Based on an analysis of outcrops, well logs and high resolution seismic data, the sedimentary system types and distribution characteristics of the Paleogene in the east part of Kuqa foreland basin were systematically studied. The results show that: ( 1 ) Three types of sedimentary systems are developed in the area: an oxidative salty wide shallow lacustrine system, a fan delta system and an evaporitic bordersea system. (2) The configuration and evolution of the depositional systems of the Paleogene in the Kuqa foreland basin were predominantly determined by foreland tectonism. Vertically, the Paleogene sedimentary sequence can be divided into three parts: the lower, middle and upper depositional system tracts. The lower and upper tracts commonly consist of progradational or aggradational sequences, while the middle part is usually comprised of a set of aggradational to transgressive third-order sequences. Laterally, the sedimentary systems in the east part of the Kuqa foreland basin spread from east to west as a whole, and the sedimentary facies obviously vary from south to north. The sand bodies of the delta front facies are excellent gas reservoirs, characterized by rather thick, extensive and continuous distribution, high porosity and permeability, and just a few barrier beds.

  4. Elastic Properties of Sedimentary Rocks (United States)

    Melendez Martinez, Jaime

    Sedimentary rocks are an important research topic since such rocks are associated to sources of ground water as well as oil, gas, and mineral reservoirs. In this work, elastic and physical properties of a variety of sedimentary samples that include glacial sediments, carbonates, shales, one evaporite, and one argillite from a variety of locations are investigated. Assuming vertical transverse isotropy, ultrasonic compressional- and shear-waves (at 1 MHz central frequency) were measured as a function of confining pressure on all samples with the exception of glacial samples which were tested assuming isotropy. Tensile strength tests (Brazilian test) were also carried out on selected glacial samples and, in addition, static-train measurements were conducted on shales and argillite samples. Lithological and textural features of samples were obtained through thin section techniques, scanning electron microscopy images and micro-tomography images. X-ray diffraction and X-Ray fluorescence provided the mineralogical oxides content information. Porosity, density, and pore structure were studied by using a mercury intrusion porosimeter and a helium pycnometer. The wide range of porosities of the studied samples (ranging from a minimum of 1% for shales to a maximum 45% for some glacial sediments) influence the measured velocities since high porosity sample shows an noticeable velocity increment as confining pressure increases as a consequence of closure of microcracks and pores, unlike low porosity samples where increment is quasi-lineal. Implementation of Gassmann's relation to ultrasonic velocities obtained from glacial samples has negligible impact on them when assuming water saturated samples, which suggests that state of saturation it is no so important in defining such velocities and instead they are mainly frame-controlled. On the other hand, velocities measured on carbonate and evaporite samples show that samples are at best weak anisotropic, thus the intrinsic

  5. Introduction history and population genetics of the invasive grass Bromus tectorum (Poaceae) in Canada. (United States)

    Valliant, Morgan T; Mack, Richard N; Novak, Stephen J


    The invasive annual Bromus tectorum (cheatgrass) is distributed in Canada primarily south of 52° N latitude in two diffuse ranges separated by the extensive coniferous forest in western Ontario. The grass was likely introduced independently to eastern and western Canada post-1880. We detected regional variation in the grass's genetic diversity using starch gel electrophoresis to analyze genetic diversity at 25 allozyme loci in 60 populations collected across Canada. The Pgm-1a & Pgm-2a multilocus genotype, which occurs in the grass's native range in Eastern Europe, is prevalent in eastern Canada but occurs at low frequency in western Canada. In contrast, the Got-4c multilocus genotype, found in the native range in Central Europe, is widespread in populations from western Canada. Overall genetic diversity of B. tectorum is much higher in eastern Canada than in the eastern U.S., while the genetic diversity in populations in western North America is similar between Canada and the U.S. The distribution of genetic diversity across Canada strongly suggests multiple introduction events. Heterozygous individuals, which are exceedingly rare in B. tectorum, were detected in three Canadian populations. Formation of novel genotypes through occasional outcrossing events could spark adaptive evolution and further range expansion across Canada of this exceedingly damaging grass.

  6. The tectonic development and erosion of the Knox Subglacial Sedimentary Basin, East Antarctica (United States)

    Maritati, A.; Aitken, A. R. A.; Young, D. A.; Roberts, J. L.; Blankenship, D. D.; Siegert, M. J.


    Sedimentary basins beneath the East Antarctic Ice Sheet (EAIS) have immense potential to inform models of the tectonic evolution of East Antarctica and its ice-sheet. However, even basic characteristics such as thickness and extent are often unknown. Using airborne geophysical data, we resolve the tectonic architecture of the Knox Subglacial Sedimentary Basin in western Wilkes Land. In addition, we apply an erosion restoration model to reconstruct the original basin geometry for which we resolve geometry typical of a transtensional pull-apart basin. The tectonic architecture strongly indicates formation as a consequence of the rifting of India from East Gondwana from ca. 160-130 Ma, and we suggest a spatial link with the western Mentelle Basin offshore Western Australia. The erosion restoration model shows that erosion is confined within the rift margins, suggesting that rift structure has strongly influenced the evolution of the Denman and Scott ice streams.

  7. Correspondence Between Astronomical Periods and Sedimentary Cycles

    Institute of Scientific and Technical Information of China (English)

    Cheng Rihui; You Haitao


    It is shown from detailed study that there are some genetic relationships between outer events of celestial bodies and inner geological events of the earth, such as some kinds of correspondences between astronomical periods and sedimentary cycles. The time spans of movement periods of the solar system around the center of the galaxy and cross the plain of the galaxy, the periods of the earth orbit (Milankovitch period) and periods of sunspot are coincided with that of respective sedimentary cycles. It is suggested that the gravity and magnetic changes of the earth leading up to the global climatic and sea level changes are the dynamics of sedimentary cycles.

  8. Layer Formation in Sedimentary Fingering Convection

    CERN Document Server

    Reali, J F; Alsinan, A; Meiburg, E


    When particles settle through a stable temperature or salinity gradient they can drive an instability known as sedimentary fingering convection. This phenomenon is thought to occur beneath sediment-rich river plumes in lakes and oceans, in the context of marine snow where decaying organic materials serve as the suspended particles, or in the atmosphere in the presence of aerosols or volcanic ash. Laboratory experiments of Houk and Green (1973) and Green (1987) have shown sedimentary fingering convection to be similar to the more commonly known thermohaline fingering convection in many ways. Here, we study the phenomenon using 3D direct numerical simulations. We find evidence for layer formation in sedimentary fingering convection in regions of parameter space where it does not occur for non-sedimentary systems. This is due to two complementary effects. Sedimentation affects the turbulent fluxes and broadens the region of parameter space unstable to the $\\gamma$-instability (Radko 2003) to include systems at l...

  9. Biogenic and terrigenous coarse fractions in surface sediments of the western Arctic Ocean and their sedimentary environments%西北冰洋表层沉积物中生源和陆源粗组分及其沉积环境

    Institute of Scientific and Technical Information of China (English)

    孙烨忱; 王汝建; 肖文申; 陈建芳; 程振波; 陈志华; 高爱国; 李洪亮


    Strait.High surface productivity in the western Chukchi Sea is resulted from the hyperhaline and hypertrophic Anadyr Stream, whereas low planktonic siliceous productivity in its eastern part is caused by the hypohaline and hypotrophic Alaska Coastal Stream.High planktonic calcareous productivity in the Chukchi Sea Plateau and Alpha Ridge is ascribed to the impact of the northern Atlantic water mass.Low planktonic calcareous productivity in the Chukchi Sea shelf is attributed to the terrigenous matter dilution and life depth of calcareous microorganism.Low calcareous planktonic productivity in the Canada Basin is responded to the strong CaCO3 dissolution.Distribution of terrigenous coarse fraction (ice-rafted detritus-IRD) in the western Arctic Ocean is influenced mainly by sea ice and iceberg transport, terrestrial ice input, river and Pacific currents.The terrigenous coarse fraction in the Bering Strait is impacted by the Pacific currents entering into the Chukehi Sea through Bering Strait.The terrigenous coarse fraction near Alaska coastal area is transported by the terrestrial ice and river.The high IRD in the Northwind Ridge is contributed by the massive sea ice and icebergs conveyed by the Beaufort Circulation, and deposited at the seafloor when the sea ice and icebergs melt.

  10. Uranium industry in Canada

    Energy Technology Data Exchange (ETDEWEB)


    Current state of uranium industry in Canada has been considered. It is shown that in Canada, which is the major supplier of uranium, new methods of prospecting, mining and processing of uranium are developed and the old ones are improved. Owing to automation and mechanization a higher labour productivity in uranium ore mining is achieved. The uranium industry of Canada can satisfy the future demands in uranium but introduction of any new improvement will depend completely on the rate of nuclear power development.

  11. Determination of petrophysical properties of sedimentary rocks by optical methods (United States)

    Korte, D.; Kaukler, D.; Fanetti, M.; Cabrera, H.; Daubront, E.; Franko, M.


    Petrophysical properties of rocks (thermal diffusivity and conductivity, porosity and density) as well as the correlation between them are of great importance for many geoscientific applications. The porosity of the reservoir rocks and their permeability are the most fundamental physical properties with respect to the storage and transmission of fluids, mainly oil characterization. Accurate knowledge of these parameters for any hydrocarbon reservoir is required for efficient development, management, and prediction of future performance of the oilfield. Thus, the porosity and permeability, as well as the chemical composition must be quantified as precisely as possible. This should be done along with the thermal properties, density, conductivity, diffusivity and effusivity that are intimately related with them. For this reason, photothermal Beam Deflection Spectrometry (BDS) technique for determination of materials' thermal properties together with other methods such as Energy Dispersive X-ray Scanning Electron Microscopy (SEM-EDX) for determining the chemical composition and sample structure, as well as optical microscopy to determine the particles size, were applied for characterization of sedimentary rocks. The rocks were obtained from the Andes south flank in the Venezuela's western basin. The validation of BDS applicability for determination of petrophysical properties of three sedimentary rocks of different texture and composition (all from Late Cretaceous associated with the Luna, Capacho and Colón-Mito Juan geological formations) was performed. The rocks' thermal properties were correlated to the microstructures and chemical composition of the examined samples.

  12. One Canada, Two Languages

    Institute of Scientific and Technical Information of China (English)

    ByMurrayGreig; 赵金前


    Canada is one of the few nations in theworld to have two official languages: Englishand French. There are 10 provinces in thecountry but only one of these--Quebec isknown as "French Canada". This is because itwas founded by French explorers while Britishadventurers discovered the rest.

  13. Linking recent observations of cyclic steps from fjords to outcropping stratigraphic products, British Columbia, Canada (United States)

    Hubbard, S. M.; Coutts, D. S.; Covault, J. A.


    Repeated bathymetric surveys of fjord prodeltas in Western Canada track channel erosion and deposition, which is interpreted to result from upstream migrating cyclic steps. Cyclic steps are long-wave (the ratio of wavelength to height is >>1), upstream-migrating bedforms that develop as a result of repeated internal hydraulic jumps in an overriding turbidity current at lee-to-stoss slope breaks. An internal hydraulic jump is the result of a transition from subaqueous densimetric Froude supercritical to subcritical flow. As the supercritical bedforms migrate greater than 90% of the deposits are reworked, making morphology- and facies- based recognition challenging in the depositional record. The objectives of this work are to use predictions of remnant bedform geometry from repeat bathymetric surveys to recognize cyclic step deposits in the stratigraphic record. We compare fjord deposits to Late Cretaceous submarine channel strata of the Nanaimo Group at Gabriola Island, British Columbia. In the Squamish prodelta, sediment accumulation on the stoss side of cyclic steps and erosion on the lee side promotes their up-slope migration. Deposits are modified by overriding turbidity currents, resulting in sedimentary bodies 5-30 m long, 0.5-2 m thick and migrating cyclic step deposits inform a revised interpretation of a high gradient channel setting dominated by supercritical flow in the Nanaimo Group. The outcrop perspective, tied to data from seafloor surveys, offers insights into the stratigraphy and preservation potential of these bedforms.

  14. Sedimentary environments: processes, facies, and stratigraphy

    National Research Council Canada - National Science Library

    Reading, H. G; Reading, Harold G


    ... and chemical systems, 6 2.1.2 Climate, 7 2.1.3 Tectonic movements and subsidence, 11 2.1.4 Sea-level changes, 11 2.1.5 Milankovitch processes and orbital forcing, 14 2.1.6 Intrinsic sedimentary processes,...

  15. Sedimentary porphyrins: Correlations with biological precursors

    Energy Technology Data Exchange (ETDEWEB)

    Callot, H.J.; Ocampo, R.; Albrecht, P. (Universite Louis Pasteur, Strasbourg (France))

    Over the past 6 years several sedimentary porphyrins (petroporphyrins, geoporphyrins) were correlated for the first time with biological precursors specific for classes of organisms (algae, photosynthetic bacteria (Chlorobiaceae)). This article discusses the various examples of correlations and the methods that led to these conclusions (isolation of pure porphyrins, structure determination using spectroscopic techniques, total synthesis, isotope measurements).

  16. Sedimentary Environments Offshore Norway - Palaeozoic to Recent

    Energy Technology Data Exchange (ETDEWEB)

    Martinsen, Ole J.; Dreyer, Tom [eds.


    The report includes the extended abstracts from the conference, 71 in number. The presentations discuss the sedimentary characteristics of the North Sea area and the the methods used in the research, a thorough knowledge of which is important for economic exploration of the oil and gas resources of the North Sea.

  17. Canada and veterinary parasitology. (United States)

    Slocombe, J Owen D


    A World Association for the Advancement of Veterinary Parasitology tradition for its conference is to present some highlights of the country hosting the event, and with an emphasis on the history of, and research in, veterinary parasitology. A review of Canada's peoples, physiography, climate, natural resources, agriculture, animal populations, pioneers in veterinary parasitology, research accomplishments by other veterinary parasitologists, centres for research in veterinary parasitology, and major current research had been presented at a World Association for the Advancement of Veterinary Parasitology Conference in Canada in 1987, and was published. The present paper updates the information on the above topics for the 22 years since this conference was last held in Canada.

  18. Is delta sup(15)N of sedimentary organic matter a good proxy for paleodenitrification in coastal waters of the eastern Arabian Sea?

    Digital Repository Service at National Institute of Oceanography (India)

    Agnihotri, R.; Naqvi, S.W.A.; Kurian, S.; Altabet, M.A.; Bratton, J.F.

    on the western continental shelf off Goa, the observed contrasting behavior (decreasing trend; Plate 1) of sedimentary d 15 N raises important questions con- cerning regional N isotope systematics. 4. SEDIMENTARY d 15 N RECORDS OF PERU-CHILE MARGIN... that this record exhibits two distinct trends of variability during the last 250 years: (1) Intensifi- cation of interdecadal variability of southerly winds along the arid coast of northern Chile/southern Peru since the 19th century, especially from 1820 to 1878...

  19. Spatial variations in geochemical characteristics of the modern Mackenzie Delta sedimentary system (United States)

    Vonk, Jorien E.; Giosan, Liviu; Blusztajn, Jerzy; Montlucon, Daniel; Graf Pannatier, Elisabeth; McIntyre, Cameron; Wacker, Lukas; Macdonald, Robie W.; Yunker, Mark B.; Eglinton, Timothy I.


    The Mackenzie River in Canada is by far the largest riverine source of sediment and organic carbon (OC) to the Arctic Ocean. Therefore the transport, degradation and burial of OC along the land-to-ocean continuum for this riverine system is important to study both regionally and as a dominant representative of Arctic rivers. Here, we apply sedimentological (grain size, mineral surface area), and organic and inorganic geochemical techniques (%OC, δ13C-OC and Δ14C-OC, 143Nd/144Nd, δ2H and δ18O, major and trace elements) on particulate, bank, channel and lake surface sediments from the Mackenzie Delta, as well as on surface sediments from the Mackenzie shelf in the Beaufort Sea. Our data show a hydrodynamic sorting effect resulting in the accumulation of finer-grained sediments in lake and shelf deposits. A general decrease in organic carbon (OC) to mineral surface area ratios from river-to-sea furthermore suggests a loss of mineral-bound terrestrial OC during transport through the delta and deposition on the shelf. The net isotopic value of the terrestrial OC that is lost en route, derived from relationships between δ13C, OC and surface area, is -28.5‰ for δ13C and -417‰ for Δ14C. We calculated that OC burial efficiencies are around 55%, which are higher (∼20%) than other large river systems such as the Amazon. Old sedimentary OC ages, up to 12 14C-ky, suggest the delivery of both a petrogenic OC source (with an estimated contribution of 19 ± 9%) as well as a pre-aged terrestrial OC source. We calculated the 14C-age of this pre-aged, biogenic, component to be about 6100 yrs, or -501‰, which illustrates that terrestrial OC in the watershed can reside for millennia in soils before being released into the river. Surface sediments in lakes across the delta (n = 20) showed large variability in %OC (0.92-5.7%) and δ13C (-30.7‰ to -23.5‰). High-closure lakes, flooding only at exceptionally high water levels, hold high sedimentary OC contents (>2.5%) and

  20. Mecaster batnensis (Coquand, 1862), a late Cenomanian echinoid from New Mexico, with a compilation of Late Cretaceous echinoid records in the Western Interior of the United States and Canada (United States)

    Hook, Stephen C.; Cobban, William A.


    Echinoids are rare in the Upper Cretaceous of the Western Interior, where fewer than 60 unique occurrences are known to date, most of these represented by only a few tests or isolated spines. A notable exception is the Carthage coal field (Socorro County, New Mexico), where more than 200 specimens of Mecaster batnensis, previously referred to as Hemiaster jacksoni Maury, 1925, have been collected from the basal Bridge Creek Limestone Beds of the Tokay Tongue of the Mancos Shale. Prolific occurrences from the same beds are known from elsewhere in west-central and southwest New Mexico. Recorded originally from the Upper Cretaceous of Algeria, M. batnensis is a small- to medium-sized, irregular echinoid that is confined to the upper Cenomanian Euomphaloceras septemseriatum Zone in New Mexico. Measurements on 169 well-preserved specimens from two localities in New Mexico document a species that is, on average, 21.0 mm long, 19.8 mm wide, and 15.1 mm tall, yielding a width/length ratio of 0.94 and a height/length ratio of 0.72. Graphs plotting width against length and height against length are strongly linear. The Western Interior echinoid record spans the entire Late Cretaceous, although there are no records from rocks of Santonian age. Localities are spread from New Mexico on the south to Alberta on the north. Preservation ranges from coarse internal molds in high-energy sandstones to original tests in low-energy limestones.

  1. Amino acids in the sedimentary humic and fulvic acids

    Digital Repository Service at National Institute of Oceanography (India)

    Sardessai, S.

    to the coastal sedimentary humic acids implying higher association of amino acids with the carbonaceous and fine grained sedimentary humic acids. Both the humic and fulvic acids are composed of neutral, acidic, basic, aromatic and sulphur containing amino acids....

  2. A Preliminary Analysis of Relations Between Tectonic Deformation of Sedimentary Cover and Basement in Kuqa Depression

    Institute of Scientific and Technical Information of China (English)

    Liu Jie; Qu Guosheng; Tong Xiaoguang; Song Huizhen; Zhou Qing; Zhang Ning


    Study of seismic activity in the Kuqa area enables us to infer some possible active faults in basement from the ePicentral distribution on different profiles. The relations between active faults in the basement and surface structures are analyzed and the difference between sedimentary cover and basement in their deformation characteristics and the genesis are discussed. The following conclusions have been drawn: (1) the epicentral distribution indicates that, the east Qiulitag and south and north Qiulitag deep faults in the basement correspond to the east and west Qiulitag anticlines, respectively. Moreover, deep faults also exist beneath the Yiqiklik and Yaken anticlines. It indicates that the formation of surface structures is controlled by deep structures; (2) A NE-trending strike-slip fault develops along the line from the western termination of Yiqiklik structure to Dongqiu Well 5 and a NW-trending active fault on the western side of Baicheng. The two active faults across the tectonic strike are the main causes for tectonic segmentation of the Kuqa depression and possibly the cause for the middle segment (Kuqa-Baicheng) of the depression to be more shortened than both its eastern and western terminations; (3) The difference between the sedimentary cover and basement in their deformation characteristics depends mainly on the different properties of media between them.The lithospheric strength of the basement in the basin is fairly high, which determines the basement deformation to be mainly of brittle fracture seismic activity. While the strength of sedimentary cover is low, where there exist weak thin layers, such as coal and gyps. Under the effect of strong tectonic compression, the sedimentary rocks may undergo strong viscous or plastic flow deformation; meanwhile, an aseismic detachment may take place along the weak layers.

  3. Sedimentary Environments and Geochemical Characteristics of Early Permian Carbonate Platform in the Western Henan Province%豫西地区早二叠世碳酸盐岩台地沉积环境及地球化学特征

    Institute of Scientific and Technical Information of China (English)

    姚旭; 周瑶琪; 李素


    焦作-禹州地区下二叠统太原组沉积相可划分为5类:开阔台地相、局限台地相、障壁岛相、泻湖-沼泽相和潮坪相,海相碳酸盐岩地层中风暴沉积事件普遍发育。开阔台地主要发育生物碎屑灰岩,生物碎屑含量高且较为破碎,以 LREE 明显富集,∑REE、(LREE /HREE)N值与 Fe 含量正相关为特点,反映古水体开阔、动荡且富含生物碎屑和胶体。局限台地主要沉积泥晶灰岩,古水体环境表现为受限、相对安静的特点。研究区太原组下部灰岩段的底部灰岩形成于海侵体系域(TST),生物碎屑含量、∑REE 相对较高且轻重稀土无显著分异,Sr/Ba 比值小而 Ba 丰度高;顶部灰岩形成于高水位体系域(HST),显示台地水体逐渐受到限制,陆源控制作用减弱,演化为更加安静低能环境。不同体系域中局限台地灰岩的对比分析,可为恢复南华北二叠纪陆表海盆地古地理特征及演化提供重要资料。%This paper presents the study of the sedimentary facies of Taiyuan Formation in typical sections from Jiaozuo area to Yuzhou area,mainly focusing on the platform sedimentary characteristics and evolution of epi-continental sea.Sedimentary facies of Taiyuan Formation,which is mainly featured by limestones along with in-terlayered siltstones,mud shales and coal seams,can be divided into five facies including open carbonate plat-form,limited carbonate platform,barrier island,lagoon-swamp and tidal-flat facies.The storm depositional events widely developed in the carbonate platform,which can be divided into several sedimentary cycles.Open carbonate platform (mainly in Yuzhou area)mainly contain amount of bioclastic,featured by substantial broken fossils,high content of trace elements and rare earth elements,much higher content of LREE than that of HREE,the respectively positive correlations between the value of ∑REE and the content of Fe as well as between

  4. A Tentative Study of Learning Support Service Systems of Trinity Western University in Canada%加拿大西三一大学(TWU)学习支持服务制度初探

    Institute of Scientific and Technical Information of China (English)



    The support service system of student learning is one of the important parts of develo-ping talents systems in universities of Canada.Under the guidance of the concept of service and leadership,TWU has built the student learning supporting agencies and systems, which including the academic, spiritual, physical, entertainment, learning support services, such as school culture and institutional systems.By improving the ability and level of student support services, the university is famous for its quality and service and has gained high praise by student survey and social recogni-tion.The systems and experiences of the higher education institution are of great enlightenment and reference to the support service system of student learning system of higher education institutions in China.%学习支持服务制度,是大学培养人才的重要制度之一。加拿大西三一大学在“服务与领导”理念指导下,通过构建学术、精神、身体、娱乐、学校文化等支持服务机构与制度而形成学生支持服务的体系,提高支持服务的能力与水平,获得社会与学生的好评。本文在学习的基础上对其进行了深入的分析与探索,并提出了对我国内地大学建构学习支持服务机构与制度的三点启示。

  5. Chronology and stratigraphy of the Magdalen Islands archipelago from the last glaciation to the early Holocene: new insights into the glacial and sea-level history of eastern Canada

    DEFF Research Database (Denmark)

    Rémillard, Audrey M.; St-Onge, Guillaume; Bernatchez, Pascal


    The Magdalen Islands (Québec, Canada) are a key location for unravelling the glacial and sea-level history of the Maritime Provinces of eastern Canada. Although many sedimentary sequences have been described in the literature, absolute ages are lacking, impeding an accurate interpretation of the ...

  6. Western Sufism

    DEFF Research Database (Denmark)

    Sedgwick, Mark

    Western Sufism is sometimes dismissed as a relatively recent "new age" phenomenon, but in this book, Mark Sedgwick argues that it actually has very deep roots, both in the Muslim world and in the West. In fact, although the first significant Western Sufi organization was not established until 1915......, the first Western discussion of Sufism was printed in 1480, and Western interest in some of the ideas that are central to Sufi thought goes back to the thirteenth century. Sedgwick starts with the earliest origins of Western Sufism in late antique Neoplatonism and early Arab philosophy, and traces later...

  7. Mineralogical study of surface sediments in the western Arctic Ocean and their implications for material sources

    Institute of Scientific and Technical Information of China (English)

    DONG Linsen; SHI Xuefa; LIU Yanguang; FANG Xisheng; CHEN Zhihua; WANG Chunjuan; ZOU Jianjun; HUANG Yuanhui


    Mineralogical analysis was performed on bulk sediments of 79 surface samples using X-ray diffraction. The analytical results, combined with data on ocean currents and the regional geological background, were used to investigate the mineral sources. Mineral assemblages in sediments and their distribution in the study area indicate that the material sources are complex. (1) Feldspar is abundant in the sediments of the middle Chukchi Sea near the Bering Strait, originating from sediments in the Anadyr River carried by the Anadyr Current. Sediments deposited on the western side of the Chukchi Sea are rich in feldspar. Compared with other areas, sediments in this region are rich in hornblende transported from volcanic and sedimentary rocks in Siberia by the Anadyr Stream and the Siberian Coastal Current. Sediments in the eastern Chukchi Sea are rich in quartz sourced from sediments of the Yukon and Kuskokwim rivers carried by the Alaska Coastal Current. Sediments in the northern Chukchi Sea are rich in quartz and carbonates from the Mackenzie River sediments. (2) Sediments of the southern and central Canada Basin contain little calcite and dolomite, mainly due to the small impact of the Beaufort Gyre carrying carbonates from the Canadian Arctic Islands. Compared with other areas, the mica content in the region is high, implying that the Laptev Sea is the main sediment source for the southern and central Canada Basin. In the other deep sea areas, calcite and dolomite levels are high caused by the input of large amounts of sediment carried by the Beaufort Gyre from the Canadian Arctic Islands (Banks and Victoria). The Siberian Laptev Sea also provides small amounts of sediment for this region. Furthermore, the Atlantic mid-water contributes some fine-grained material to the entire deep western Arctic Ocean.


    Directory of Open Access Journals (Sweden)

    G. I. Leychenkov


    Full Text Available In early February 2012, the drill hole at the Vostok Station encountered theLakeVostokwater. This step is important to study the lake composition including possible microbial life and to model subglacial environments however, the next ambitious target of the Vostok Drilling Project is sampling of bottom sediments, which contain the unique record of ice sheet evolution and environmental changes in centralAntarcticafor millions of years. In this connection, the forecast of sedimentary succession based on existing geophysical data, study of mineral inclusions in the accretion ice cores and tectonic models is important task. Interpretation of Airborne geophysical data suggests thatLakeVostokis the part of spacious rift system, which exists at least from Cretaceous. Reflection and refraction seismic experiments conducted in the southern part ofLakeVostokshow very thin (200–300 m stratified sedimentary cover overlying crystalline basement with velocity of 6.0–6.2 km/s. At present, deposition in southernLakeVostokis absent and similar conditions occurred likely at least last3 m.y. when ice sheet aboveLakeVostokchanged insignificantly. It can be also inferred that from the Late Miocene the rate of deposition inLakeVostokwas extremely low and so the most of sedimentary section is older being possibly of Oligocene to early to middle Miocene age when ice sheet oscillated and deposition was more vigorous. If so, the sampling of upper few meters of this condensed section is very informative in terms of history of Antarctic glaciation. Small thickness of sedimentary cover raises a question about existence of lake (rift depression during preglacial and early glacial times.

  9. Understanding and modeling the sedimentary system


    Hay, William W


    The sedimentary system involves processes that weather rocks and reduce them to soluble and fine-grained particulate components that can be transported. deposited, and transformed back into rock. !Jost of the processes can be observed today, but the present is an unusual episode in our planet's history. We live in a brief warm interglacial epi sode in an interval usually characterized by large mid-and high-latitude icc sheets and a much lower sea level. To com...

  10. GEOID '88: A gravimetric geoid for Canada (United States)

    Nagy, Dezso


    Using Stokes' formula, a gravimetric geoid was calculated for Canada. The input data are as follows: 15 x 15' block averages were used for Canada and the USA and 1 x 1 deg block averages and satellite model (GEM-T1) provided values for the remaining part of the Earth. The geoid was calculated at 6398 points covering the area within the points rho(sub i)(phi sub i; lambda sub i) (lambda is + west): rho sub 1(40,125); rho sub 2(75,184); rho sub 3(75,10); and rho sub 4(40,60). The computed geoid refers to the GRS1980 and reaches a local minimum of -47.3 meters around the western part of Hudson Bay. A contour map of the geoid is shown.

  11. Pain medicine--a new credential in Canada. (United States)

    Morley-Forster, Patricia; Karpinski, Jolanta


    In 2010, Pain Medicine was formally recognized as a subspecialty in Canada by the Royal College of Physicians and Surgeons of Canada, a national organization with oversight of the medical education of specialists in Canada. The first trainees began their training at the Western University, London, Canada in July, 2014. This article traces the process of Pain Medicine's development as a discipline in Canada and outlines its multiple entry routes, 2-year curriculum, and assessment procedures. The application for specialty status was initiated in 2007 with the understanding that while Anesthesiology would be the parent specialty, the curriculum would train clinicians in a multidisciplinary setting. To receive recognition as a Royal College subspecialty, Pain Medicine had to successfully pass through three phases, each stage requiring formal approval by the Committee on Specialties. The multiple entry routes to this 2-year subspecialty program are described in this article as are the objectives of training, the curriculum, assessment of competency and the practice-eligibility route to certification. The process of accreditation of new training programs across Canada is also discussed. The new Pain Medicine training program in Canada will train experts in the prevention, diagnosis, treatment and rehabilitation of the spectrum of acute pain, cancer pain and non-cancer pain problems. These physicians will become leaders in education, research, advocacy and administration of this emerging field. Wiley Periodicals, Inc.

  12. Technical Note: n-Alkane lipid biomarkers in loess: post-sedimentary or syn-sedimentary?

    Directory of Open Access Journals (Sweden)

    D. Faust


    Full Text Available There is an ongoing discussion whether n-alkane biomarkers – and organic matter (OM from loess in general – reflect a syn-sedimentary paleoenvironmental and paleoclimate signal or whether they are significantly a post-sedimentary feature contaminated by root-derived OM. We present first radiocarbon data for the n-alkane fraction of lipid extracts and for the first time luminescence ages for the Middle to Late Weichselian loess-paleosol sequence of Gleina in Saxony, Germany. Comparison of these biomarker ages with sedimentation ages as assessed by optically stimulated luminescence (OSL dating shows that one n-alkane sample features a syn-sedimentary age (14C: 29.2 ± 1.4 kyr cal BP versus OSL: 27.3 ± 3.0 kyr. By contrast, the 14C ages derived from the other n-alkane samples are clearly younger (20.3 ± 0.7 kyr cal BP, 22.1 ± 0.7 kyr cal BP and 29.8 ± 1.4 kyr cal BP than the corresponding OSL ages (26.6 ± 3.1 kyr, 32.0 ± 3.5 kyr and 45.6 ± 5.3 kyr. This finding suggests that a post-sedimentary n-alkane contamination presumably by roots has occurred. In order to estimate the post-sedimentary n-alkane contamination more quantitatively, we applied a 14C mass balance calculation based on the measured pMC (percent modern carbon values, the calculated syn-sedimentary pMC values and pMC values suspected to reflect likely time points of post-sedimentary contamination (current, modern, 3 kyr, 6 kyr and 9 kyr. Accordingly, current and modern root-contamination would account for up to 7%, a 3 kyr old root-contamination for up to 10%, and an Early and Middle Holocene root-contamination for up to 20% of the total sedimentary n-alkane pool. We acknowledge and encourage that these first radiocarbon results need further confirmation both from other loess-paleosol sequences and for different biomarkers, e.g. carboxylic acids or alcohols as further lipid biomarkers.

  13. Correlating biodegradation to magnetization in oil bearing sedimentary rocks (United States)

    Emmerton, Stacey; Muxworthy, Adrian R.; Sephton, Mark A.; Aldana, Milagrosa; Costanzo-Alvarez, Vincenzo; Bayona, German; Williams, Wyn


    A relationship between hydrocarbons and their magnetic signatures has previously been alluded to but this is the first study to combine extensive geochemical and magnetic data of hydrocarbon-associated samples. We report a detailed study that identifies a connection between magnetic mineralogy and oil biodegradation within oil-bearing sedimentary units from Colombia, Canada Indonesia and the UK. Geochemical data reveal that all the oil samples are derived from mature type-II kerogens deposited in oxygen-poor environments. Biodegradation is evident to some extent in all samples and leads to a decrease in oil quality through the bacterially mediated conversion of aliphatic hydrocarbons to polar constituents. The percentage of oil components and the biodegradation state of the samples were compared to the magnetic susceptibility and magnetic mineralogy. A distinct decrease in magnetic susceptibility is correlated to decreasing oil quality and the amount of extractable organic matter present. Further magnetic characterization revealed that the high quality oils are dominated by pseudo-single domain grains of magnetite and the lower quality oils by larger pseudo-single domain to multidomain grains of magnetite and hematite. Hence, with decreasing oil quality there is a progressive dominance of multidomain magnetite as well as the appearance of hematite. It is concluded that biodegradation is a dual process, firstly, aliphatic hydrocarbons are removed thereby reducing oil quality and secondly, magnetic signatures are both created and destroyed. This complex relationship may explain why controversy has plagued previous attempts to resolve the connection between magnetics and hydrocarbon deposits. These findings reinforce the importance of bacteria within petroleum systems as well as providing a platform for the use of magnetization as a possible exploration tool to identify subsurface reservoirs and a novel proxy of hydrocarbon migration.

  14. Sedimentary particulate iron: the missing micronutrients ? (United States)

    Beghoura, Houda; Gorgues, Thomas; Aumont, Olivier; Planquette, Hélène


    Iron is known to regulate the marine primary production and to impact the structure of ecosystems. Indeed, iron is the limiting nutrient for the phytoplankton growth over about 30% of the global ocean. However, the nature of the external sources of iron to the ocean and their quantification remain uncertain. Among these external sources, the sediment sources have been recently shown to be underestimated. Besides, since the operationally defined dissolved iron (which is the sum of truly dissolved and colloidal iron) was traditionally assumed to be the only form available to phytoplankton and bacteria, most studies have focused on the supply of dissolved iron to the ocean, the role of the particulate fraction of iron being largely ignored. This traditional view has been recently challenged, noticeably, by observational evidences. Indeed, in situ observations have shown that large amounts of particulate iron are being resuspended from continental margins to the open ocean thanks to fine grained particles' transport over long distances. A fraction of this particulate iron may dissolve and thereby fuel the phytoplankton growth. The magnitude of the sedimentary sources of particulate iron and the releasing processes affecting this iron phase are not yet well constrained or quantified. As a consequence, the role of sedimentary particulate iron in the biogeochemical cycles is still unclear despite its potentially major widespread importance. Here, we propose a modeling exercise to assess the first order impacts of this newly considered particulate sedimentary iron on global ocean biogeochemistry. We designed global experiments with a coupled dynamical-biogeochemical model (NEMO-PISCES). First, a control simulation that includes only a sediment source of iron in the dissolved phase has been run. Then, this control simulation is being compared with simulations, in which we include a sediment source of iron in both phases (dissolved as well as particulate). Those latter

  15. In Canada: Friendly Fire (United States)

    Robertson, Heather-jane


    One of Canada's more frequently quoted political malapropisms is attributed to Robert Thompson, who sternly reminded his fellow parliamentarians in 1973 that "the Americans are our best friends, whether we like it or not." This cross-border friendship is partly expedient, partly geographic, partly genuine, sometimes one-sided, and almost always…

  16. IYPE in Canada (United States)

    Boyd, J.; Nowlan, G.


    The Canadian National Committee picked five of the ten IYPE themes for emphasis in Canada - Water, Hazards, Energy, Resources and Environment. They are summarized in the acronym WHERE - WHERE on Earth, WHERE in Canada. Our committee raised funds from industry, with some generous support from The Geological Survey of Canada. Funds were used for publishing “Four Billion Years and Counting”, a book on Canadian geology designed for the general public. It will be useful to educators who can download many of the illustrations and images for classroom support. Recognizing the looming shortage of Geoscientists, we designed a new careers website to help attract young people to the Earth sciences. It can be seen on our website, The website will be updated regularly. The WHERE Challenge was a national contest for children aged 10 to 14. They were asked to select an object, often something from their household, identify at least one non-renewable resource used to make the object, and submit an entry describing the object, the resources within it, and WHERE they came from. We received entries from more than 1000 students Some of the winning entries are posted on our website. We developed a partnership with Parks Canada called Egoists, which is a series of pamphlets on iconic views within the parks explaining the Earth science behind the views. We also supported the celebration of the 100th anniversary of the discovery of the Burgess Shale by providing funding for the publication of a field guide. At the end of the year all programs will transfer to the Canadian Federation of Earth Sciences. The WHERE Challenge will be repeated in 2010. It, plus our book and careers website will continue our outreach activities.

  17. STONE 6: Sedimentary meteors from Mars (United States)

    Westall, F.; Demets, R.; Brandstetter, F.; Edwards, H. G. M.; Cockell, C. S.; Parnell, J.; Foucher, F.; Kurat, G.; Brack, A.


    STONE 6 is a space experiment to test the potential for survival of sedimentary meteors from Mars surviving entry into the Earth's atmosphere. Two sediments and a basalt (as the control) were embedded close to the ablation point of the heat shield of a FOTON M3 capsule for atmospheric entry from lower Earth orbit in September 2007. The sediments included (1) an ~3.5 billion year (Ga) old volcanic sand containing carbonaceous microfossils and (2) an ~370 million year (Ma) old lacustrine rock containing chemical biomarkers. The backs of the samples were smeared with a living endolithic microorganism, Chroococcidiopsis. The sediments survived reentry, as did some of the chemical biomarkers in the lacustrine sediment and the carbonaceous microfossils in the 3.5 Ga-old sediment survived (away from the fusion crust). An increase in the crystallinity of the carbon in both sediments was noted. The Chroococcidiopsis did not survive but their carbonised remains did. Thus sedimentary meteorites from Mars could reach the surface of the Earth and, if they contain traces of fossil life, these traces could be preserved. However, living organisms may need more than 2cm of rock protection.

  18. Synthetic and sedimentary records of geomagnetic excursions (United States)

    Vlag, P.; Thouveny, N.; Rochette, P.

    The geomagnetic excursion recorded in the sediments of Lac St.Front (Massif Central, France) is characterized by shallow and negative inclinations followed by a younger steep inclination interval (Vlag et al., 1996). In the corresponding interval of the nearby Lac du Bouchet only steep inclinations are found. Sedimentary records of the Mono Lake excursion show similar inclination patterns; ‘complete’ records of this excursion show a succession of a shallow by a steep inclination interval, while ‘incomplete’ records only show only steep inclinations (Coe and Liddicoat, 1994). Due to a non-instantaneous acquisition of the remanence, sedimentary records reflect only a smoothed geomagnetic signal. It will be shown that smoothing of a small low-intensity ‘reversed’ interval embedded in a non-antipodal normal field interval may result in records of a shallow inclination interval followed by a steep inclination interval, while further smoothing results in only steep inclinations. Realignment of magnetic grains by the stronger normal field can also produce such records and may explain why such an unusual large lock-in depth is required by the conventional smoothing model. Whatever the mechanism, the similarities between these synthetic records and the excursional records of Lac St. Front-Lac du Bouchet and Mono Lake suggest that the latter are more or less affected by vector addition of two non-antipodal directions.

  19. The sedimentary structure of linear sand dunes (United States)

    Bristow; Bailey; Lancaster


    Linear sand dunes--dunes that extend parallel to each other rather than in star-like or crescentic forms--are the most abundant type of desert sand dune. But because their development and their internal structure are poorly understood, they are rarely recognized in the rock record. Models of linear dune development have not been able to take into account the sub-surface structure of existing dunes, but have relied instead either on the extrapolation of short-term measurements of winds and sediment transport or on observations of near-surface internal sedimentary structures. From such studies, it has not been clear if linear dunes can migrate laterally. Here we present images produced by ground penetrating radar showing the three-dimensional sedimentary structure of a linear dune in the Namib sand sea, where some of the world's largest linear dunes are situated. These profiles show clear evidence for lateral migration in a linear dune. Moreover, the migration of a sinuous crest-line along the dune produces divergent sets of cross-stratification, which can become stacked as the dune height increases, and large linear dunes can support superimposed dunes that produce stacked sets of trough cross-stratification. These clear structural signatures of linear dunes should facilitate their recognition in geological records.

  20. Multiple water isotope proxy reconstruction of extremely low last glacial temperatures in Eastern Beringia (Western Arctic)

    NARCIS (Netherlands)

    Porter, Trevor J.; Froese, Duane G.; Feakins, Sarah J.; Bindeman, Ilya N.; Mahony, Matthew E.; Pautler, Brent G.; Reichart, Gert-Jan; Sanborn, Paul T.; Simpson, Myrna J.; Weijers, Johan W H


    Precipitation isotopes are commonly used for paleothermometry in high latitude regions. Here we present multiple water isotope proxies from the same sedimentary context - perennially frozen loess deposits in the Klondike Goldfields in central Yukon, Canada, representing parts of Marine Isotope Stage

  1. Multiple water isotope proxy reconstruction of extremely low last glacial temperatures in Eastern Beringia (Western Arctic)

    NARCIS (Netherlands)

    Porter, T.J.; Froese, D.G.; Feakins, S.J.; Bindeman, I.N.; Mahony, M.E.; Pautler, B.G.; Reichart, G.-J.; Sanborn, P.T.; Simpson, M.J.; Weijers, J.W.H.


    Precipitation isotopes are commonly used for paleothermometry in high latitude regions. Here we present multiple water isotope proxies from the same sedimentary context – perennially frozen loess deposits in the Klondike Goldfields in central Yukon, Canada, representing parts of Marine Isotope Stage

  2. Thallium contamination of water in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Cheam, V. [National Water Research Institute Branch, Burlington, ON (Canada). Aquatic Ecosystems Protection Research Branch


    A highly sensitive instrument, a Laser-Excited Atomic Fluorescence Spectrometer, has been developed to study thallium contamination in some important Canadian ecosystems from the Arctic (containing very low thallium concentration) to coal-related industries across Canada and even to the study of thallium toxicity in an invertebrate, Hyalella azteca. Overall, the data indicate that the coal power plants and mines contain higher thallium concentrations than the other ecosystems studied, and the eastern region has the highest Tl concentrations compared to other regions. The range of thallium concentration in ng/L for the Arctic snow and ice was between not detected and 8.4, for the Great Lakes waters 0.9 to 48, for pore waters 0.1 to 213, for western coal power plants and mines 0.1 to 1326, for central coal power plants 1.2 to 175, for eastern coal power plants and mines 0.2 to 23605, and for miscellaneous sites across Canada not detected to 4390 ng/L. Some of these high concentrations and those high ones reported in industrial wastewaters exceeded the chronic toxicity endpoints for Hyalella azteca mortality, growth and reproduction, and thus can cause serious distress to the environment. All data were integrated into a map of thallium distribution, the first one in Canada. Natural background level of thallium for the Arctic was estimated to be 0.02 to 0.03 pg/g.

  3. DEWI partnership in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Dutilleux, P.; Klug, H.; Molly, J.P. [DEWI, Wilhelmshaven (Germany)


    Canada is with its 9.982.000 km{sup 2} the second largest country in the world. It has plenty of natural resources for a population density of 3 inhabitants per km{sup 2}. Now that the time for wind energy is coming, DEWI is willing to contribute with its know-how to the development of wind energy in this country. In this article we review briefly two of the market drivers for the development of wind energy: the need for additional electricity generation capacity and the political framework. After considering the volume of projects under development, a way is shown how DEWI will be present in Canada in order to support its clients. (orig.)

  4. Neogene sedimentary evolution of Baja California in relation to regional tectonics (United States)

    Helenes, J.; Carreño, A. L.


    During the Neogene, the tectonic and sedimentary evolution of the Baja California Peninsula followed four stages: (1) during the early Miocene (22 Ma), the initiation of transform motion between Pacific and North American plates, caused a rapid subsidence in the Continental Borderland Province and in some adjacent areas.This subsidence coincided in time with with a global rise in sea level. At this time, the eastern and southern parts of the peninsula did not show any evidence of subsidence. (2) During the middle Miocene (12 Ma), normal and strike slip faulting migrated eastward, causing subsidence in the northern part of the Gulf of California, where the oldest Tertiary marine sedimentary rocks were deposited. The areas in central Baja California Sur and the central part of the Gulf itself received abundant volcanic deposits related to continental extension. (3) During the late Miocene (8 Ma), the western margin of the Peninsula changed to a slightly compressive regime, while the northern part of the Gulf contained a marine basin with upper bathyal environments. The central area of the Gulf continued receiving abundant volcanic deposits, while the Los Cabos block received marine sedimentation, correlatable with sedimentary units reported from the continental margins in Nayarit, Jalisco and Michoacán. (4) Beginning in the early Pliocene (5 Ma), the present configuration of the Gulf of California developed through right-lateral strike slip and extension in the Gulf itself. Since Pliocene times, the Gulf presents widespread marine sedimentation with deep basins reaching lower bathyal depths.

  5. Transnational surrogacy: Canada's contradictions. (United States)

    Lozanski, Kristin


    Transnational commercial surrogacy represents a form of medical tourism undertaken by intended parents who seek to hire women in other countries, increasingly often in the global South, as surrogates. While much of the scholarly literature focuses on the conditions of surrogacy within host countries, such as India, there has been limited analysis of transnational surrogacy focused upon origin countries. In this article, I build upon the scholarship that explores the impact of host country structures on transnational surrogacy, with special attention to the significance of Canadian citizenship policy through analysis of legislation and policy vis-à-vis transnational commercial surrogacy. The Canadian case demonstrates clear contradictions between the legislation and policy that is enacted domestically to prohibit commercial surrogacy within Canada and legislation and policy that implicitly sanctions commercial surrogacy through the straightforward provision of citizenship for children born of such arrangements abroad. The ethical underpinnings of Canada's domestic prohibition of commercial surrogacy, which is presumed to exploit women and children and to impede gender equality, are violated in Canada's bureaucratic willingness to accept children born of transnational commercial surrogacy as citizens. Thus, the ethical discourses apply only to Canadian citizens within Canadian geography. The failure of the Canadian government to hold Canadian citizens who participate in transnational commercial surrogacy to the normative imperatives that prohibit the practice within the country, or to undertake a more nuanced, and necessarily controversial, discussion of commercial surrogacy reinforces transnational disparities in terms of whose bodies may be commodified as a measure of gendered inequality.

  6. Environmental performance reviews: Canada

    Energy Technology Data Exchange (ETDEWEB)



    OECD's comprehensive 2004 report on Canada's environmental policies and programmes systematically examines policy related to air, water, and nature/biodiversity as well as the interface between environmental policy and economic policy, social policy, and specific sectors. It finds that while Canada has made satisfactory progress since 1985, there are still significant challenges, and the report makes specific recommendations for more use of economic instruments and use of the polluter and user pays principles, rationalising water governance, strengthening nature protection, reducing energy intensity, implementing climate change policies, reviewing environmentally related taxes, and implementing marine and aid commitments. Coal provides about 20% of Canada's electric power. Most direct subsidisation of the fossil fuel supply industries (upstream oil, gas and coal) has been reduced. The report recommends subsidies to the mining industry for exploration should also be phased out. Recent measurements indicate emissions of mercury are increasing, mainly due to long-range transboundary air pollution from coal-burning plants. 42 figs., 24 tabs.

  7. Antimicrobial resistance in Canada (United States)

    Conly, John


    Antibiotic resistance has increased rapidly during the last decade, creating a serious threat to the treatment of infectious diseases. Canada is no exception to this worldwide phenomenon. Data from the Canadian Nosocomial Infection Surveillance Program have revealed that the incidence of methicillin-resistant Staphylococcus aureus, as a proportion of S. aureus isolates, increased from 1% in 1995 to 8% by the end of 2000, and vancomycin-resistant enterococcus has been documented in all 10 provinces since the first reported outbreak in 1995. The prevalence of nonsusceptible Streptococcus pneumoniae in Canada in 2000 was found to be 12%. Human antimicrobial prescriptions, adjusted for differences in the population, declined 11% based on the total number of prescriptions dispensed between 1995 and 2000. There was also a 21% decrease in β-lactam prescriptions during this same period. These data suggest that systematic efforts to reduce unnecessary prescribing of antimicrobials to outpatients in Canada, beginning after a national consensus conference in 1997, may be having an impact. There is, however, still a need for continued concerted efforts on a national, provincial and regional level to quell the rising tide of antibiotic resistance. PMID:12406948

  8. Midwifery education in Canada. (United States)

    Butler, Michelle M; Hutton, Eileen K; McNiven, Patricia S


    This article is part of a special series on midwifery education and describes the approach to midwifery education in Canada We begin with an overview of the model of midwifery practice introduced in Canada in the 1990s. We describe the model of midwifery education developed and report how it is implemented, with particular attention to the two longest established programs. Midwifery education programs in Ontario and British Columbia. Midwifery education programs in Canada are offered at the undergraduate baccalaureate level at universities and are typically four years in length. Programs are competence-based and follow a spiral curriculum. The first semesters focus on on core sciences, social sciences and introduction to midwifery concepts. Students spend fifty percent of the program in clinical practices with community-based midwives. Innovative education models enable students to be placed in distant placements and help to align theoretical and practice components. Clinically active faculty adds to the credibility of teaching but bring its own challenges for midwifery educators. The Canadian model of midwifery education has been very effective with low attrition rates and high demand for the number of places available. Further program expansion is warranted but is contingent on the growth of clinical placements. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. A Method for Determining Sedimentary Micro-Facies Belts Automatically

    Institute of Scientific and Technical Information of China (English)

    Linfu Xue; Qitai Mei; Quan Sun


    It is important to understand the distribution of sedimentary facies, especially the distribution of sand body that is the key for oil production and exploration. The secondary oil recovery requires analyzing a great deal of data accumulated within decades of oil field development. At many cases sedimentary micro-facies maps need to be reconstructed and redrawn frequently, which is time-consuming and heavy. This paper presents an integrated approach for determining the distribution of sedimentary micro-facies, tracing the micro-facies boundary, and drawing the map of sedimentary micro-facies belts automatically by computer technique. The approach is based on the division and correlation of strata of multiple wells as well as analysis of sedimentary facies. The approach includes transform, gridding, interpolation, superposing, searching boundary and drawing the map of sedimentary facies belts, and employs the spatial interpolation method and "worm" interpolation method to determine the distribution of sedimentary micro-facies including sand ribbon and/or sand blanket. The computer software developed on the basis of the above principle provides a tool for quick visualization and understanding the distribution of sedimentary micro-facies and reservoir. Satisfied results have been achieveed by applying the technique to the Putaohua Oil Field in Songliao Basin, China.

  10. Ancient sedimentary environments and their subsurface diagnosis, third edition

    Energy Technology Data Exchange (ETDEWEB)

    Selley, R.C.


    All the worlds coal, most of its petroleum, and many ore deposits occur within sedimentary rocks (sandstones, limestones and shales). The distribution of these minerals is closely related to the sedimentary environment of the host rock. For example, an oil field trapped in an old beach sand will be elongated parallel to the basin margin, while a bed of coal within an abandoned river channel will trend into the basin. This book shows how to diagnose the depositional environments of sedimentary rocks and indicates how this knowledge may be applied to the search for petroleum, coal and sedimentary ore deposits. The first edition of this book appeared in 1970. It was primarily concerned with the interpretation of sedimentary environments from outcrop, from an aesthetic stance, with no thought of vulgar commercial application. The second edition (1977) reflected the author's experience in the oil industry and included sections on the use of geophysical well logs in subsurface facies analysis. In recent years the field that is loosely termed seismic stratigraphy developed, where sedimentary concepts are applied to the interpretation of seismic data. Today seismic surveys may delineate channels, deltas, reefs, submarine fans, and other deposits. The thrid edition contains sections on the seismic characteristics of the various sedimentary facies, and the sections on metalliferous sedimentary deposits and recent environments have been expanded.

  11. Canada Finance Minster:Welcome China's Investment in Canada

    Institute of Scientific and Technical Information of China (English)

    Guo Yan


    @@ To forward the relationship between China and Canada in financial and trade sectors and strengthen the cooperation in avoiding the worse impact of international financial crisis,Canadian financial high-level leaders involving Bank of Canada Governor Mark Carney,Canada's Minister of Finance Jim Flaherty,Federal Superintendent of Financial Institutions Julie well as tive malor banks and the two biggest insurance companies in Canada,who are lpoking to strengthen and expand business ties with China,visited China from August 8 to August 14,2009.

  12. 78 FR 78321 - Endangered and Threatened Wildlife and Plants; Proposed Threatened Status for the Western... (United States)


    ...; Proposed Threatened Status for the Western Distinct Population Segment of the Yellow-Billed Cuckoo... proposal to list the yellow-billed cuckoo in the western portion of the United States, Canada, and Mexico (western yellow-billed cuckoo) as a threatened distinct population segment (DPS) under the...

  13. Visualizing the sedimentary response through the orogenic cycle using multi-dimensional scaling (United States)

    Spencer, C. J.; Kirkland, C.


    Changing patterns in detrital provenance through time have the ability to resolve salient features of an orogenic cycle. Such changes in the age spectrum of detrital minerals can be attributed to fluctuations in the geodynamic regime (e.g. opening of seaways, initiation of subduction and arc magmatism, and transition from subduction to collisional tectonics with arrival of exotic crustal material). These processes manifest themselves through a variety of sedimentary responses due to basin formation, transition from rift to drift sedimentation, or inversion and basement unroofing. This generally is charted by the presence of older detrital zircon populations during basement unroofing events and is followed by a successive younging in the detrital zircon age signature either through arrival of young island arc terranes or the progression of subduction magmatism along a continental margin. The sedimentary response to the aforementioned geodynamic environment can be visualized using a multi-dimensional scaling approach to detrital zircon age spectra. This statistical tool characterizes the "dissimilarity" of age spectra of the various sedimentary successions, but importantly also charts this measure through time. We present three case studies in which multi-dimensional scaling reveals additional useful information on the style of basin evolution within the orogenic cycle. The Albany-Fraser Orogeny in Western Australia and Grenville Orogeny (sensu stricto) in Laurentia demonstrate clear patterns in which detrital zircon age spectra become more dissimilar with time. In stark contrast, sedimentary successions from the Meso- to Neoproterozoic North Atlantic Region reveal no consistent pattern. Rather, the North Atlantic Region reflects a signature consistent with significant zircon age communication due to a distal position from an orogenic front, oblique translation of terranes, and complexity of the continental margin. This statistical approach provides a mechanism to

  14. Sedimentary charateristics and hydrocarbon accumulation in Northeast Sichuan basin

    Institute of Scientific and Technical Information of China (English)

    Jianming LI; Xiling WU; Rufeng LI; Liangjie TANG; Lei LI


    Northeast Sichuan basin is a Mesozoic-Cenozoic basin in the northern margin of the Yangtze plate which has a complex tectonic background and hydrocarbon accumulation history.By means of the analysis method of wave processes,major cycles of sedimentary wave process in this basin have been studied.The results show that there are five-order cycles corresponding to 760,220,100,35 and 20 Ma respectively,two first-order sedimentary cycles (220 Ma) and four secondorder sedimentary cycles (100 Ma).The authors find that the second-order sedimentary cycles are well matched with reservoir formation cycles through studying the relationship between second-order sedimentary cycles and reservoir formation cycles,and divide three reservoir formation cycles in this basin.

  15. Geothermal Energy Potential in Low Enthalpy Areas as a Future Energy Resource: Identifying Feasible Targets, Quebec, Canada, Study Case


    Jacek Majorowicz; Vasile Minea


    Heat flow of the sedimentary succession of the Eastern Canada Sedimentary Basins varies from 40 mW/m2 close to the exposed shield in the north to high 60–70 mW/m2 in the southwest–northeast St. Lawrence corridor. As high fluid flow rates are required for a successful geothermal application, the most important targets are deep existing permeable aquifers rather than hard rock, which would need to be fracked. Unfortunately, the ten most populated Québec urban centers are in the areas where the ...

  16. Continental growth seen through the sedimentary record (United States)

    Dhuime, Bruno; Hawkesworth, Chris J.; Delavault, Hélène; Cawood, Peter A.


    Sedimentary rocks and detrital minerals sample large areas of the continental crust, and they are increasingly seen as a reliable archive for its global evolution. This study presents two approaches to model the growth of the continental crust through the sedimentary archive. The first builds on the variations in U-Pb, Hf and O isotopes in global databases of detrital zircons. We show that uncertainty in the Hf isotope composition of the mantle reservoir from which new crust separated, in the 176Lu/177Hf ratio of that new crust, and in the contribution in the databases of zircons that experienced ancient Pb loss(es), adds some uncertainty to the individual Hf model ages, but not to the overall shape of the calculated continental growth curves. The second approach is based on the variation of Nd isotopes in 645 worldwide fine-grained continental sedimentary rocks with different deposition ages, which requires a correction of the bias induced by preferential erosion of younger rocks through an erosion parameter referred to as K. This dimensionless parameter relates the proportions of younger to older source rocks in the sediment, to the proportions of younger to older source rocks present in the crust from which the sediment was derived. We suggest that a Hadean/Archaean value of K = 1 (i.e., no preferential erosion), and that post-Archaean values of K = 4-6, may be reasonable for the global Earth system. Models built on the detrital zircon and the fine-grained sediment records independently suggest that at least 65% of the present volume of continental crust was established by 3 Ga. The continental crust has been generated continuously, but with a marked decrease in the growth rate at 3 Ga. The period from > 4 Ga to 3 Ga is characterised by relatively high net rates of continental growth (2.9-3.4 km3 yr- 1 on average), which are similar to the rates at which new crust is generated (and destroyed) at the present time. Net growth rates are much lower since 3 Ga (0

  17. Indicateurs cles au Canada


    Warren, Paul


    Au cours des dernieres annees, on s'est beaucoup interesse sur la scene internationale aux indicateurs cles. Le present document se veut un tour d'horizon des efforts deployes recemment au Canada en vue d'elaborer des indicateurs cles du bien etre economique, social, environnemental et physique. Y sont classifies et examines en detail plus de 40 projets et publications portant sur ce sujet. Y figurent aussi l'enumeration breve de 20 autres projets, ainsi que des renvois a plusieurs enquetes a...


    Directory of Open Access Journals (Sweden)

    M. C. SPADEA


    Full Text Available Per strati sedimentari intendiamo quelli di origine alluvionale,
    che formano il fondo di valli e di estese pianure; non solo, ma anche
    gli strati di già consolidati che si sono formati nell'eocene e nel cretaceo.
    È noto che le stazioni sismiche poste sopra stratificazioni alluvionali
    più o meno spessi e consolidati, registrano, specie in occasione di
    terremoti ad origine vicina, tutta una serie di oscillazioni, non facilmente
    interpretabili, derivanti appunto da fenomeni di riflessione, rifrazione
    e diffrazione dovuti al passaggio dell'energia sismica attraverso
    le superficie o le zone che separano gli uni dagli altri strati costituenti
    la coltre alluvionale. È noto pure che generalmente, quando
    questi strati hanno una determinata potenza, provocano un'amplificazione
    dell'onda sismica.
    Avviene così che le stazioni di registrazione che si trovano alla
    stessa distanza da un epicentro ma sono poste su stratificazioni di diversa
    origine, registrano lo stesso terremoto in modo sensibilmente
    diverso: quelle su stratificazioni alluvionali con tutto un seguito di
    ampie oscillazioni, non sempre interpretabili, mentre i sismogrammi
    registrati da stazioni poste su roccia risultano costituiti, a parità di
    altre condizioni, di fasi meno ampie ma molto più chiare e intervallate.

  19. Investigating Coccolithophorid Biology in the Sedimentary Laboratory (United States)

    McClelland, H. L. O.; Barbarin, N.; Beaufort, L.; Hermoso, M.; Rickaby, R. E. M.


    Coccolithophores are the ocean's dominant calcifying phytoplankton; they play an important, but poorly understood, role in long-term biogeochemical climatic feedbacks. Calcite producing marine organisms are likely to calcify less in a future world where higher carbon dioxide concentrations will lead to ocean acidification (OA), but coccolithophores may be the exception. In coccolithophores calcification occurs in an intracellular vesicle, where the site of calcite precipitation is buffered from the external environment and is subject to a uniquely high degree of biological control. Culture manipulation experiments mimicking the effects of OA in the laboratory have yielded empirical evidence for phenotypic plasticity, competition and evolutionary adaptation in asexual populations. However, the extent to which these results are representative of natural populations, and of the response over timescales of greater than a few hundred generations, is unclear. Here we describe a new sediment-based proxy for the PIC:POC (particulate inorganic to particulate organic carbon ratio) of coccolithophore biomass, which is equivalent to the fractional energy contribution to calcification at constant pH, and a biologically meaningful measure of the organism's tendency to calcify. Employing the geological record as a laboratory, we apply this proxy to sedimentary material from the southern Pacific Ocean to investigate the integrated response of real ancient coccolithophore populations to environmental change over many thousands of years. Our results provide a new perspective on phenotypic change in real populations of coccolithophorid algae over long timescales.

  20. Microbial shaping of sedimentary wrinkle structures (United States)

    Mariotti, G.; Pruss, S. B.; Perron, J. T.; Bosak, T.


    Wrinkle structures on sandy bed surfaces were present in some of the earliest sedimentary environments, but are rare in modern environments. These enigmatic millimetre- to centimetre-scale ridges or pits are particularly common in sediments that harbour trace fossils and imprints of early animals, and appeared in the aftermath of some large mass extinctions. Wrinkle structures have been interpreted as possible remnants of microbial mats, but the formation mechanism and associated palaeoenvironmental and palaeoecological implications of these structures remain debated. Here we show that microbial aggregates can form wrinkle structures on a bed of bare sand in wave tank experiments. Waves with a small orbital amplitude at the bed surface do not move sand grains directly. However, they move millimetre-size, light microbial fragments and thereby produce linear sand ridges and rounded scour pits at the wavelengths observed in nature within hours. We conclude that wrinkle structures are morphological biosignatures that form at the sediment-water interface in wave-dominated environments, and not beneath microbial mats as previously thought. During early animal evolution, grazing by eukaryotic organisms may have temporarily increased the abundance of microbial fragments and thus the production of wrinkle structures.

  1. Sedimentary environment indicators: Benzothiazole and its derivatives

    Institute of Scientific and Technical Information of China (English)


    Benzothiazoles distributional characteristics of crude oils and non-hydrocarbon fractions of source rocks in Mangya depression of the Qaidam Basin, Lunnan oil field in the Tarim Basin, Kelamayi oil field in the Junggar Basin and the Tulufan Basin oil field were analyzed. It was found that the distributions of benzothiazole are remarkable diversity in different sedimentary environmental oils. The swamp crude oils contain high quantity of benzothiazole and relatively high quantity of alkylthio-benzothiazole and 2(3H)-benzothiazolone. But the quantity of the 2,2′-dithiobis- ben-zothiazole is relatively low. The abundance of benzothiazole and 2,2′-dithiobis-benzothiazole are relatively high in semi-brackish water lacustrine crude oils, but the quantity of alkylthio-benzothiazole and 2(3H)-benzothiazolone are rela-tively low. The benzothiazoles belong to weak acid and mild base compound, and their stabilization conditions relate to their environmental medium. The nitrogenous bases are in favor of alkalescence environment, while weak acid nitroge-nous compounds are the main stable products under the weak acid environment. Benzothiazoles have great signifi-cance in identifying the oil- and gas-formed environment and the geochemistry study of non-hydrocarbon fraction in the future.

  2. Sedimentary Geothermal Feasibility Study: October 2016

    Energy Technology Data Exchange (ETDEWEB)

    Augustine, Chad [National Renewable Energy Lab. (NREL), Golden, CO (United States); Zerpa, Luis [Colorado School of Mines, Golden, CO (United States)


    The objective of this project is to analyze the feasibility of commercial geothermal projects using numerical reservoir simulation, considering a sedimentary reservoir with low permeability that requires productivity enhancement. A commercial thermal reservoir simulator (STARS, from Computer Modeling Group, CMG) is used in this work for numerical modeling. In the first stage of this project (FY14), a hypothetical numerical reservoir model was developed, and validated against an analytical solution. The following model parameters were considered to obtain an acceptable match between the numerical and analytical solutions: grid block size, time step and reservoir areal dimensions; the latter related to boundary effects on the numerical solution. Systematic model runs showed that insufficient grid sizing generates numerical dispersion that causes the numerical model to underestimate the thermal breakthrough time compared to the analytic model. As grid sizing is decreased, the model results converge on a solution. Likewise, insufficient reservoir model area introduces boundary effects in the numerical solution that cause the model results to differ from the analytical solution.

  3. 西北冰洋阿尔法脊晚第四纪的陆源沉积物记录及其古环境意义%Late Quaternary Terrigenous Sedimentation in the Western Arctic Ocean as Exemplified by a Sedimentary Record from the Alpha Ridge

    Institute of Scientific and Technical Information of China (English)

    刘伟男; 王汝建; 陈建芳; 程振波; 陈志华; 孙烨忱


    通过西北冰洋阿尔法脊B84A孔中—晚第四纪以来的沉积物颜色旋回,Mn、Ca元素相对含量、颜色反射率、有孔虫丰度、冰筏碎屑(IRD)含量、粒度组分及其敏感性分析的综合研究,建立了B84A孔的地层年代框架,其沉积物被划分为MIS 12~MIS 1的沉积序列。阿尔法脊B84A孔可以识别出12个IRD事件,它们大多出现在冰消期,并认为其源区为加拿大北极群岛地区。这些IRD事件反映了加拿大北极冰盖的崩塌和气候变化。阿尔法脊B84A孔沉积物的环境敏感组分分别为细组分(4~9μm)和粗组分(19~53μm),两者的变化趋势相反,主要由海冰和洋流进行搬运,指示了洋流的强度变化。B84A孔的平均沉积速率约为0.4 cm/ka,与阿尔法脊周围地区沉积速率相近。相比于近岸的高沉积速率,其限制因素主要为大面积海冰覆盖造成的较低的生产力和由于长距离搬运造成的较低的陆源输入量。%Terrigenous components in sediment core B84A from the Alpha Ridge,western Arctic Ocean,have been investigated to reconstruct the Mid to Late Quaternary variations in sedimentation,source regions,and related climate changes.The core stratigraphy,evaluated by a combination of variations in Mn content,color cycles,foraminiferal abundance,and lithological correlation,extends back to estimated Marine Isotope Stage(MIS) 12.Twelve ice rafted detritus(IRD,〉250 μm) events were identified and interpreted to mostly occur during the deglacial periods.The Canadian Arctic covered by ice sheets during glacial periods is suggested to be the major source region.The IRD events likely indicate the collapses of ice sheets,possibly in relation to abrupt climate changes.Grain size analysis of B84A indicates sedimentologically sensitive components in core B84A in the silt subfractions 4~9 μm and 19~53 μm,which are inferred to be mainly transported by currents and sea ice

  4. Q Fever Update, Maritime Canada (United States)

    Marrie, Thomas J.; Campbell, Nancy; McNeil, Shelly A.; Webster, Duncan


    Since the 1990s, reports of Q fever in Nova Scotia, Canada, have declined. Passive surveillance for Q fever in Nova Scotia and its neighboring provinces in eastern Canada indicates that the clinical manifestation of Q fever in the Maritime provinces is pneumonia and that incidence of the disease may fluctuate. PMID:18258080

  5. Canada and the Third World. (United States)

    Burghardt, Andrew F.


    Canada did not develop strong ties with the Third World until well after World War II. Three factors that have channeled and limited Canada's relationships with developing nations--location, history, and internal political relationships--are discussed. Also examined are patterns of Canadian foreign aid and investment and peace-seeking efforts. (RM)

  6. Canada's Dominion Astrophysical Observatory and the rise of 20th Century Astrophysics and Technology (United States)

    Hesser, James E.; Bohlender, David; Crabtree, Dennis


    Construction of Canada's Dominion Astrophysical Observatory (DAO) commenced in 1914 with first light on 6 May 1918. As distinct from the contemporaneous development with private funding of major observatories in the western United States, DAO was (and remains) funded by the federal government. Canada's initial foray into `big science', creation of DAO during the First World War was driven by Canada's desire to contribute significantly to the international rise of observational astrophysics enabled by photographic spectroscopy. In 2009 the Observatory was designated a National Historic Site. DAO's varied, rich contributions to the astronomical heritage of the 20th century continue in the 21st century, with particularly strong ties to Maunakea.

  7. Mackenzie River Delta, Canada (United States)


    The Mackenzie River in the Northwest Territories, Canada, with its headstreams the Peace and Finley, is the longest river in North America at 4241 km, and drains an area of 1,805,000 square km. The large marshy delta provides habitat for migrating Snow Geese, Tundra Swans, Brant, and other waterfowl. The estuary is a calving area for Beluga whales. The Mackenzie (previously the Disappointment River) was named after Alexander Mackenzie who travelled the river while trying to reach the Pacific in 1789. The image was acquired on August 4, 2005, covers an area of 55.8 x 55.8 km, and is located at 68.6 degrees north latitude, 134.7 degrees west longitude. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  8. Contaminant Research in Canada

    Directory of Open Access Journals (Sweden)

    Wren C.


    Full Text Available Contaminant Research in CanadaPages 9 - 11 (ReportChristopher WrenAbstract:During the 1983/84 and 1984/85 trapping seasons, carcasses of river otter (Lutra canadensis were collected for contaminant analysis from trappers in Ontario. The studies identified clear differences in tissue levels of Hg, Pb and Cd between different collection areas. There is evidence to support Hg poisoning as the cause of death in at least one otter along this river system. The studies emphasize the potential interactions of toxic chemicals with each other and with natural stresses (e.g. cold, starvation, disease. More research is required along these lines since simultaneous exposure to more than one chemical and other stresses is more typical of conditions in the wild.

  9. Compromised wounds in Canada. (United States)

    Denny, Keith; Lawand, Christina; Perry, Sheril D


    Wounds are a serious healthcare issue with profound personal, clinical and economic implications. Using a working definition of compromised wounds, this study examines the prevalence of wounds by type and by healthcare setting using data from hospitals, home care, hospital-based continuing care and long-term care facilities within fiscal year 2011-2012 in Canada. It also evaluates several risk factors associated with wounds, such as diabetes, circulatory disease and age. Compromised wounds were reported in almost 4% of in-patient acute hospitalizations and in more than 7% of home care clients, almost 10% of long-term care clients and almost 30% of hospital-based continuing care clients. Patients with diabetes were much more likely to have a compromised wound than were patients without the disease. Copyright © 2014 Longwoods Publishing.

  10. Archaen to Recent aeolian sand systems and their sedimentary record

    DEFF Research Database (Denmark)

    Rodríguez-López, Juan Pedro; Clemmensen, Lars B; Lancaster, Nick


    The sedimentary record of aeolian sand systems extends from the Archean to the Quaternary, yet current understanding of aeolian sedimentary processes and product remains limited. Most preserved aeolian successions represent inland sand-sea or dunefield (erg) deposits, whereas coastal systems...... are primarily known from the Cenozoic. The complexity of aeolian sedimentary processes and facies variability are under-represented and excessively simplified in current facies models, which are not sufficiently refined to reliably account for the complexity inherent in bedform morphology and migratory...... behaviour, and therefore cannot be used to consistently account for and predict the nature of the preserved sedimentary record in terms of formative processes. Archean and Neoproterozoic aeolian successions remain poorly constrained. Palaeozoic ergs developed and accumulated in relation...

  11. Alteration of Sedimentary Clasts in Martian Meteorite Northwest Africa 7034 (United States)

    McCubbin, F. M.; Tartese, R.; Santos, A. R.; Domokos, G.; Muttik, N.; Szabo, T.; Vazquez, J.; Boyce, J. W.; Keller, L. P.; Jerolmack, D. J.; Anand, M.; Moser, D. E.; Delhaye, T.; Shearer, C. K.; Agee, C. B.


    The martian meteorite Northwest Africa (NWA) 7034 and pairings represent the first brecciated hand sample available for study from the martian surface [1]. Detailed investigations of NWA 7034 have revealed substantial lithologic diversity among the clasts [2-3], making NWA 7034 a polymict breccia. NWA 7034 consists of igneous clasts, impact-melt clasts, and "sedimentary" clasts represented by prior generations of brecciated material. In the present study we conduct a detailed textural and geochemical analysis of the sedimentary clasts.

  12. Geophysical methods for the study of sedimentary cycles

    Institute of Scientific and Technical Information of China (English)

    Xu Jingling; Liu Luofu; Wang Guiwen; Shen Jinsong; Zhang Chunhua


    We present the wavelet depth-frequency analysis and variable-scale frequency cycle analysis methods to study sedimentary cycles. The spectrum analysis, variable-scale frequency cycle analysis, and wavelet depth-frequency analysis methods are mainly discussed to distinguish sedimentary cycles of different levels. The spectrum analysis method established the relationship between the spectrum characteristics and the thickness and number of sedimentary cycles. Both the variable-scale frequency cycle analysis and the wavelet depth-frequency analysis are based on the wavelet transform. The variable-scale frequency cycle analysis is used to obtain the relationship between the periodic changes of frequency in different scales and sedimentary cycles, and the wavelet depth-frequency analysis is used to obtain the relationship between migration changes of frequency energy clusters and sedimentary cycles. We designed a software system to process actual logging data from the Changqing Oilfieid to analyze the sedimentary cycles, which verified the effectiveness of the three methods, and good results were obtained.

  13. Food control systems in Canada. (United States)

    Smith, T M; Jukes, D J


    This paper provides an overview of the responsibilities and jurisdictional boundaries of Health Canada (HC) and Agriculture and Agri-Food Canada (AAFC) with regard to food regulation in Canada. It examines their interagency coordination within the federal structure and with other levels of government, industry, and the consumer. The international developments are considered with the North American Free Trade Agreement (NAFTA) and the Canada, United States Trade Agreement (CUSTA) being regarded as likely to have a significant future impact. The federal food safety and quality system is complex and fragmented. Federal food regulation comes under the jurisdiction of four federal departments: HC, AAFC, Industry Canada (IC), and Fisheries and Oceans Canada (FOC). All four departments are involved with inspection, surveillance, and the analysis of food sold in Canada. In addition, Canada's ten provincial and two territorial governments have provincial-, regional-, municipal-, and local-level governments that also have jurisdiction over food safety and quality. Consideration is first given to the main legislative provision covering food--the Federal Food and Drugs Act. This Act is administered by several of the Federal Government departments. The role of these departments is examined individually along with additional, more specific legal provisions for which responsibility is not divided (in particular, the Canada Agricultural Products [CAP] Act administered by AAFC, and the Consumer Packaging and Labeling Act [CPLA] administered by IC). The various reviews that have taken place in the recent past and those still in progress are considered, and the final part of this paper looks at the international developments that are likely to have a major impact on the future development of the Canadian food control system.

  14. Sedimentary features and exploration targets of Middle Permian reservoirs in the SW Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Guoming Xu


    Full Text Available The exploration direction and targets for the large-scale Middle Permian gas reservoirs in the Sichuan Basin are hot spots and challenges in current exploration researches. The exploration successes of large gas field of Cambrian Longwangmiao Formation in Gaoshiti-Moxi region, Central Sichuan Basin, indicated that prospective sedimentary facies belt was the basis for the formation of large gas fields. In this paper, based on seismic data, outcrop data and drilling data, the tectonic framework and sedimentary features of the Middle Permian in the SW Sichuan Basin were comprehensively studied. The following conclusions were reached from the perspective of sedimentary facies control: (1 during the Middle Permian, this region was in shallow water gentle slope belts with high energy, where thick reef flat facies were deposited; (2 the basement was uplifted during Middle Permian, resulting in the unconformity weathering crust at the top of Maokou Formation due to erosion; the SW Sichuan Basin was located in the karst slope belt, where epigenic karstification was intense; and (3 reef flat deposits superimposed by karst weathering crust was favorable for the formation of large-scale reef flat karst reservoirs. Based on the combination of the resources conditions and hydrocarbon accumulation conditions in this region, it was pointed out that the Middle Permian has great potential of large-scale reef flat karst gas reservoir due to its advantageous geological conditions; the Middle Permian traps with good hydrocarbon accumulation conditions were developed in the Longmen Mountain front closed structural belt in the SW Sichuan Basin and Western Sichuan Basin depression slope belt, which are favorable targets for large-scale reef flat karst reservoirs.

  15. The Relationship Between Seismicity and the Oil and Gas Industry in Western Alberta and Eastern B.C. (United States)

    Atkinson, G. M.; Eaton, D. W. S.; Ghofrani, H.; Walker, D.; Cheadle, B.; Schultz, R.; Shcherbakov, R.; Tiampo, K. F.; Gu, Y. J.; Harrington, R. M.; Liu, Y.


    Significantly increased production of hydrocarbons in North America is being driven by the development of unconventional resources whose commercial viability, in many cases, depends upon massive subsurface injection of fluids. Although relatively uncommon, elevated pore pressure from fluid injection of any kind can induce earthquake activity by activating slip on a proximal fault. In the western Canada sedimentary basin (which follows the Rocky Mountain foothills region and straddles the border between Alberta and B.C.), we find that hydraulic fracture treatment, wherein fluids are injected under high pressure in long laterally-drilled wells in order to induce localized fracturing of a rock formation, is the primary triggering mechanism of induced seismicity. This contrasts with the central U.S., where most induced seismicity has been attributed to large-scale wastewater injection into deep disposal wells. Our findings are based on a comprehensive statistical analysis of seismicity at the M≥3 level since 1985, along with a complete well database for the region, containing information on many thousands of oil and gas wells. Since 2010, most of the regional earthquakes of M≥3 are correlated in both time and space with hydraulic fracturing. Monte Carlo simulations confirm that the observed correlations are extremely unlikely (<<1%) to have been obtained by chance. Improved understanding of regional variability in fault activation processes, accounting for operational and geological factors, will aid in the development and validation of predictive models for the time-dependent hazards from induced earthquakes.

  16. Canada goose behavior: Fall 1969 (United States)

    US Fish and Wildlife Service, Department of the Interior — Canada geese use four divisions of the Mark Twin NWR: Louisa, Delair, Cannon, and Calhoun. There was a shortage of cultivated crops, corn and soybeans, on all refuge...

  17. Obstetric medical care in Canada. (United States)

    Magee, Laura A; Cote, Anne-Marie; Joseph, Geena; Firoz, Tabassum; Sia, Winnie


    Obstetric medicine is a growing area of interest within internal medicine in Canada. Canadians continue to travel broadly to obtain relevant training, particularly in the United Kingdom. However, there is now a sufficient body of expertise in Canada that a cadre of 'home-grown' obstetric internists is emerging and staying within Canada to improve maternity care. As this critical mass of practitioners grows, it is apparent that models of obstetric medicine delivery have developed according to local needs and patterns of practice. This article aims to describe the state of obstetric medicine in Canada, including general internal medicine services as the rock on which Canadian obstetric medicine has been built, the Canadian training curriculum and opportunities, organisation of obstetric medicine service delivery and the future.

  18. A staff shortage in Canada?

    Energy Technology Data Exchange (ETDEWEB)

    Stoll, P. [Human Resources Development Canada, Quebec (Canada)


    Attrition of experienced staff, falling student enrolments and closure of university courses are symptoms of the contraction of the Canadian nuclear industry over the last two decades. It is not alone. A study carried out by Human Resources Development Canada, a government department, to forecast the demand for qualified nuclear staff in Canada over the next 15 years has reached similar conclusions to an OECD/NEA study of its members` future personnel requirements. (author).

  19. Perturbation induced changes in substrate use by the blue mussel, Mytilus edulis, in sedimentary systems (United States)

    wa Kangeri, Arno K.; Jansen, Jeroen M.; Barkman, Barbara R.; Donker, Jasper J. A.; Joppe, Daniel J.; Dankers, Norbert M. J. A.


    For sessile benthic marine organisms adhesion to a stable substrate is important for survival. Sedimentary systems, however, generally lack stable surfaces. How sessile species like the mussel, Mytilus edulis, are able to achieve stability in unstable sediments is not fully understood. An intertidal mussel bed in the tidal flats in the Western portion of the Dutch Wadden Sea was selected to investigate adhesion behavior of M. edulis. Sampling was conducted along a hydrodynamic gradient along the Front-edge, Center and Back-edge of a mussel bed. Mussels along the bed edges were characterized by adhesion to fine shell debris and high numbers of byssus threads. Mussels in the center of the bed were characterized by adhesion to shells of living conspecifics and relatively low numbers of byssus threads. An experimental investigation to isolate the role of perturbation on adhesion strategies was carried out under laboratory conditions. Experimental results show that under perturbed conditions mussels developed increased numbers of byssus threads relative to mussels left unperturbed. Additionally, mussels subjected to perturbation preferentially adhered more frequently to fine shell debris while unperturbed mussels adhered more frequently to conspecifics. Results show that differentiation in adhesion strategy is driven by physical perturbation and mediated by bed density. The results also suggest that adhesion by mussels in a sedimentary environment is a selective process in which larger shell fragments and shells of conspecifics are the preferred substrate.

  20. Postglacial sedimentary infill of the Bricial peatland (Cantabrian Mountains, Spain) (United States)

    Correia, Antonio; Ruiz-Fernández, Jesús; Oliva, Marc; Fernández, Antonio; García-Hernández, Cristina; Gallinar, David


    Bricial is a peatland located in a glaciokarst depression of the Western Massif of the Picos de Europa (NW Spain). The depression is 425 m long and 245 m wide, and it is surrounded by moraines built during the stage of glacial expansion after the maximum advance within the Last Glaciation. In contrast to what happens in other karstic depressions existing in this massif (e.g. Comeya), the thickness and sedimentary infill of this depression is still unknown. With the purpose of better knowing the depression's structure, two electrical resistivity tomographies (ERT)s with different lengths across the Bricial depression were conducted along perpendicular directions; the shortest ERT was done in a NNE-SSW direction with an electrode spacing of 2 m and a total length of 78 m; the longest ERT was done in a WNW-ESE direction with a 5 m electrode spacing and a total length of 195 m. Both ERTs used 40 electrodes in a Wenner configuration. The two ERTs were done in such way that they intersected near an 8 m deep borehole drilled in the area in 2006. A two-dimensional electrical inversion software was used for inverting the apparent electrical resistivity data obtained during the field work into two-dimensional models of electrical resistivity of the ground. The models are a representation of the distribution of the electrical resistivity of the ground to depths of about 14 m along the shortest ERT and 35 m along the longest. In both geoelectrical models the electrical structure is approximately horizontal at the surface (i.e., between 3 to 5 m depth) and is more complex as depth increases. Low resistivity values prevail in most part of the profiles, which is consistent with the sedimentary sequence collected in the area. The 8 m long sedimentary sequence collected from Bricial consists of homogeneous organic-rich sediments. The base of the sequence was dated at 11,150 ± 900 cal yr BP. Taking into account the sedimentation rates and the data inferred from the electrical

  1. Uncertainty quantification of overpressure buildup through inverse modeling of compaction processes in sedimentary basins (United States)

    Colombo, Ivo; Porta, Giovanni M.; Ruffo, Paolo; Guadagnini, Alberto


    This study illustrates a procedure conducive to a preliminary risk analysis of overpressure development in sedimentary basins characterized by alternating depositional events of sandstone and shale layers. The approach rests on two key elements: (1) forward modeling of fluid flow and compaction, and (2) application of a model-complexity reduction technique based on a generalized polynomial chaos expansion (gPCE). The forward model considers a one-dimensional vertical compaction processes. The gPCE model is then used in an inverse modeling context to obtain efficient model parameter estimation and uncertainty quantification. The methodology is applied to two field settings considered in previous literature works, i.e. the Venture Field (Scotian Shelf, Canada) and the Navarin Basin (Bering Sea, Alaska, USA), relying on available porosity and pressure information for model calibration. It is found that the best result is obtained when porosity and pressure data are considered jointly in the model calibration procedure. Uncertainty propagation from unknown input parameters to model outputs, such as pore pressure vertical distribution, is investigated and quantified. This modeling strategy enables one to quantify the relative importance of key phenomena governing the feedback between sediment compaction and fluid flow processes and driving the buildup of fluid overpressure in stratified sedimentary basins characterized by the presence of low-permeability layers. The results here illustrated (1) allow for diagnosis of the critical role played by the parameters of quantitative formulations linking porosity and permeability in compacted shales and (2) provide an explicit and detailed quantification of the effects of their uncertainty in field settings.

  2. Uncertainty quantification of overpressure buildup through inverse modeling of compaction processes in sedimentary basins (United States)

    Colombo, Ivo; Porta, Giovanni M.; Ruffo, Paolo; Guadagnini, Alberto


    This study illustrates a procedure conducive to a preliminary risk analysis of overpressure development in sedimentary basins characterized by alternating depositional events of sandstone and shale layers. The approach rests on two key elements: (1) forward modeling of fluid flow and compaction, and (2) application of a model-complexity reduction technique based on a generalized polynomial chaos expansion (gPCE). The forward model considers a one-dimensional vertical compaction processes. The gPCE model is then used in an inverse modeling context to obtain efficient model parameter estimation and uncertainty quantification. The methodology is applied to two field settings considered in previous literature works, i.e. the Venture Field (Scotian Shelf, Canada) and the Navarin Basin (Bering Sea, Alaska, USA), relying on available porosity and pressure information for model calibration. It is found that the best result is obtained when porosity and pressure data are considered jointly in the model calibration procedure. Uncertainty propagation from unknown input parameters to model outputs, such as pore pressure vertical distribution, is investigated and quantified. This modeling strategy enables one to quantify the relative importance of key phenomena governing the feedback between sediment compaction and fluid flow processes and driving the buildup of fluid overpressure in stratified sedimentary basins characterized by the presence of low-permeability layers. The results here illustrated (1) allow for diagnosis of the critical role played by the parameters of quantitative formulations linking porosity and permeability in compacted shales and (2) provide an explicit and detailed quantification of the effects of their uncertainty in field settings.


    Energy Technology Data Exchange (ETDEWEB)

    Thaddeus S. Dyman; Troy Cook; Robert A. Crovelli; Allison A. Henry; Timothy C. Hester; Ronald C. Johnson; Michael D. Lewan; Vito F. Nuccio; James W. Schmoker; Dennis B. Riggin; Christopher J. Schenk


    From a geological perspective, deep natural gas resources are generally defined as resources occurring in reservoirs at or below 15,000 feet, whereas ultra-deep gas occurs below 25,000 feet. From an operational point of view, ''deep'' is often thought of in a relative sense based on the geologic and engineering knowledge of gas (and oil) resources in a particular area. Deep gas can be found in either conventionally-trapped or unconventional basin-center accumulations that are essentially large single fields having spatial dimensions often exceeding those of conventional fields. Exploration for deep conventional and unconventional basin-center natural gas resources deserves special attention because these resources are widespread and occur in diverse geologic environments. In 1995, the U.S. Geological Survey estimated that 939 TCF of technically recoverable natural gas remained to be discovered or was part of reserve appreciation from known fields in the onshore areas and State waters of the United. Of this USGS resource, nearly 114 trillion cubic feet (Tcf) of technically-recoverable gas remains to be discovered from deep sedimentary basins. Worldwide estimates of deep gas are also high. The U.S. Geological Survey World Petroleum Assessment 2000 Project recently estimated a world mean undiscovered conventional gas resource outside the U.S. of 844 Tcf below 4.5 km (about 15,000 feet). Less is known about the origins of deep gas than about the origins of gas at shallower depths because fewer wells have been drilled into the deeper portions of many basins. Some of the many factors contributing to the origin of deep gas include the thermal stability of methane, the role of water and non-hydrocarbon gases in natural gas generation, porosity loss with increasing thermal maturity, the kinetics of deep gas generation, thermal cracking of oil to gas, and source rock potential based on thermal maturity and kerogen type. Recent experimental simulations

  4. Geochemical constraints on the origin of the Kicking Horse and Monarch Mississippi Valley-type lead-zinc ore deposits, southeast British Columbia, Canada (United States)

    Vandeginste, Veerle; Swennen, Rudy; Gleeson, Sarah A.; Ellam, Rob M.; Osadetz, Kirk; Roure, François


    Two Mississippi Valley-type (MVT) ore deposits, Kicking Horse and Monarch, have been studied with the aim of comparing the ores at the two localities and to characterize the origin of the mineralizing fluids and the ore formation process(es). Both deposits are hosted by the Middle Cambrian Cathedral Formation carbonate host rocks, Kicking Horse on the north and Monarch on the south flank of the Kicking Horse valley near Field (SE British Columbia). The ore bodies are situated at the transition of (western) basinal to (eastern) shallow-water strata of the paleo-Pacific passive margin succession in the Cordilleran Foreland Province of the Western Canada Sedimentary Basin. Both deposits are related spatially to normal faults. In both localities, the ore minerals are dominated by pyrite, sphalerite, and galena. Dolomite, minor quartz, and calcite are also present in close association with the ores. The salinity (21-30 wt% NaCl eq.) and homogenization temperatures (63-182°C) measured in fluid inclusions in carbonate, quartz, and sphalerite lie within the typical range of MVT fluid conditions. The good stoichiometry (50-53 mol% CaCO3), low δ18O values (-21 to -14‰ Vienna Peedee belemnite) and relatively high homogenization temperatures (>95°C) of the dolomite suggest the dolomites were formed under burial diagenesis. The ore-forming fluids probably interacted with siliciclastic units, based on elevated Li contents and 87Sr/86Sr ratios, which are highest in the dolomite type after the main ore stage. We propose that the ores formed from the mixing of a downward-infiltrating, sulfur-bearing halite-dissolution fluid with an upward-migrating, metal-rich evaporated seawater fluid, which had already undergone minor mixing with a dilute fluid.

  5. Folding and faulting of strain-hardening sedimentary rocks (United States)

    Johnson, A.M.


    The question of whether single- or multi-layers of sedimentary rocks will fault or fold when subjected to layer-parallel shortening is investigated by means of the theory of elastic-plastic, strain-hardening materials, which should closely describe the properties of sedimentary rocks at high levels in the Earth's crust. The most attractive feature of the theory is that folding and faulting, intimately related in nature, are different responses of the same idealized material to different conditions. When single-layers of sedimentary rock behave much as strain-hardening materials they are unlikely to fold, rather they tend to fault, because contrasts in elasticity and strength properties of sedimentary rocks are low. Amplifications of folds in such materials are negligible whether contacts between layer and media are bonded or free to slip for single layers of dolomite, limestone, sandstone, or siltstone in media of shale. Multilayers of these same rocks fault rather than fold if contacts are bonded, but they fold readily if contacts between layers are frictionless, or have low yield strengths, for example due to high pore-water pressure. Faults may accompany the folds, occurring where compression is increased in cores of folds. Where there is predominant reverse faulting in sedimentary sequences, there probably were few structural units. ?? 1980.

  6. Importance of the Mass Media Education: Western Cultural Dilemmas. (United States)

    Littunen, Yrjo


    Discusses features in the Western cultural background which may be relevant to changes in international opinion. Notes problems of freedom of information and cultural processes caused by mass communication among nations, including the high violence content of United States television programs compared with those of Canada and Europe. (MF)

  7. Pine Engraver, Ips pini, in the Western United States (FIDL) (United States)

    Sandra J. Kegley; R. Ladd Livingston; Kenneth E. Gibson


    The pine engraver, Ips pini (Say), is one of the most common and widely distributed bark beetles in North America. It occurs from southern Appalachia north to Maine and Quebec, westward across the northern United States and Canada, into the interior of Alaska, throughout the Pacific Coast States and the Rocky Mountain region, to northern Mexico. In the western United...

  8. Sedimentary basin analysis and petroleum potential of the Cretaceous and Tertiary strata in Korea.

    Energy Technology Data Exchange (ETDEWEB)

    Son, Jin-Dam; Kwak, Young-Hoon; Bong, Pil-Yoon [Korea Institute of Geology Mining and Materials, Taejon (KR)] (and others)


    Since 1992 sedimentary basin analysis to assess petroleum potential of the Cretaceous and Tertiary strata in the Korean onshore and continental shelf have been carried out. The Cretaceous non-marine strata mainly occupy the Gyeongsang Basin in southeastern part of the Korean Peninsula and small basins such as Haenam and Gyeokpo depressions in western coastal areas. The Tertiary strata are mostly distributed in Domi, Cheju, Socotra subbasins, and Okinawa Trough in the South Continental Shelf, and Kunsan and Heuksan basins in the West. The basin evolution and petroleum potential for each basins are characterized as follow. The Cretaceous Gyeongsang sediments were deposited in three subbasins including Milyang, Euisung and Yongyang subbasins. The black shales in Nakdong and Jinju formations are interpreted to contain abundant organic matter during the deposition, thermal maturity reaching up to the zone of dry gas formation. Because porosity and permeability are too low, the sandstones can act as a tight gas reservoir rather than conventional oil and gas reservoir. The latest Cretaceous strata of Haenam and Kyeokpo depressions in western coastal area are correlated into the Yuchon Volcanic Group of the Gyeongsang Basin. Petroleum potential of the Early Cretaceous basin in the West Continental Shelf could be relatively high in terms of sedimentary basin filled with thick lacustrine sediments. The Kunsan basin in the West Continental Shelf originated in the Early Cretaceous time expanded during the Paleocene time followed by regional erosion at the end of Paleocene on which Neogene sediment have been accumulated. The Paleocene-Eocene sublacustrine shales may play an major role as a source and cap rocks. South Continental Shelf Basin is subdivided by Cheju subbasin in the center, Socotra Subbasin to the west, Domi Subbasin to the northeast and Okinawa Trough to the East. The potential hydrocarbon traps associated with anticline, titled fault blocks, fault, unconformity

  9. Chemostratigraphy of early Neoproterozoic sedimentary rocks of Yenisei ridge (Siberia, Russia) (United States)

    Vishnevskaya, Irina; Pisareva, Natalia; Kanygina, Nadejda; Proshenkin, Artem


    One of the biggest Proterozoic sedimentary basins in Russia is around the Siberian platform. This study about little part of them - Neoproterozoic sedimentary rocks of Yenisei ridge (Southwestern margin of Siberian Platform). Thise geological structure is ancient and very difficult for reaserch. It is a collage of different blocks: volcanic arcks, ophiolite complexes and sedimentary rocks of various ages and degrees of metamorphism. Sedimentary complexes of Siberian platform are outcropping along Angara River and its tributary. Neoproterozoic ones are presented by terrigenous-carbonate rocks of Tungusik and Oslyan groups. Despite the long study history of the area is still controversial question of time of formation of these rocks. As determination of the age of Precambrian sedimentary rocks is very difficult, Sr isotopic chemostratigraphy appears to be the only approach to establish the age of carbonate sequences. All Rb-Sr author's data was investigated by the method of selective dissolution with the preliminary removal of epigenetic carbonate phases. The isotope dilution method with mixed 87Rb + 84Sr spike was used to determine Rb and Sr concentrations in both fractions on the MI 1201AT mass spectrometer. Sr isotope ratios were measured on the Finnigan MAT-262 (BAC CU, Irkutsk, Russia) and Triton Plus (IGG UB RAS, Ekaterinburg, Russia). The C-O isotopic composition in carbon samples was measured on the Finnigan MAT-253 equipment. The main criteria for integrity were correlations of impurity-elements (Mn, Fe, Sr) and stable isotopes (C, O) with each other. The less altered rocks of the Tungusik Group are characterized by 87Sr/86Sr ratio of 0.7055-0.7058, and wide variations in the δ13CPDB values from 0 to +5o [1]. The primary 87Sr/86Sr of Dashka Formation (Oslyan Group) is 0.7057 - 0.7060 and δ13CPDB value varies in interval 3.7-4.3o like in upper part of Tungusik Group. High positive values of δ13CPDB indicate that carbonates had accumulated in warm sea

  10. Septicemic listeriosis in wild hares from Saskatchewan, Canada. (United States)

    Rothenburger, Jamie L; Bennett, Katarina R; Bryan, Lorraine; Bollinger, Trent K


    The bacterium Listeria monocytogenes causes disease in a wide variety of mammals including rabbits and hares. We describe naturally acquired metritis and septicemic listeriosis in wild female hares from Saskatchewan, Canada. Between April 2012 and July 2013, two white-tailed jackrabbits (Lepus townsendii) and a snowshoe hare (Lepus americanus) were presented to the Veterinary Medical Centre at the Western College of Veterinary Medicine, Saskatoon, Saskatchewan, Canada with nonspecific neurologic signs. The hares were euthanized and autopsied. Necrotizing fibrinosuppurative metritis was present in all. Additional findings in individual hares included fetal maceration, multifocal necrotizing myocarditis, multifocal hepatic necrosis, and nonsuppurative encephalitis. Listeria monocytogenes was cultured from multiple tissues in each hare. Although listeriosis in pregnant domestic rabbits has been studied, this is the first detailed description in wild North American hares. The epidemiology of listeriosis, including prevalence and the role of environmental sources and coprophagy in transmission among hares, requires further investigation.

  11. Bone fluoride concentrations in beluga whales from Canada. (United States)

    Mikaelian, I; Qualls, C W; De Guise, S; Whaley, M W; Martineau, D


    Beluga whales (Delphinapterus leucas) from the St. Lawrence Estuary have been reported to have dental and bone abnormalities. To determine whether these lesions could be caused by high exposure to fluorides, we measured bone fluoride levels in eight beluga whales stranded on the shores of the St. Lawrence Estuary (Quebec, Canada), and in nine beluga whales killed by Inuit hunters in the Hudson Bay (North Western Territories, Canada). In both groups, fluoride concentrations were higher than those found in terrestrial mammals intoxicated by fluorides. Unexpectedly, fluoride concentration was significantly higher in beluga whales from the Hudson Bay (mean +/- SD: 10.365 +/- 1.098 ppm) than in beluga whales from the St. Lawrence Estuary (4.539 +/- 875 ppm) and was positively correlated with age in the latter population. Differences in diet might explain the differences in fluoride concentrations found between these two populations.

  12. Prediction of thermal conductivity of sedimentary rocks from well logs

    DEFF Research Database (Denmark)

    Fuchs, Sven; Förster, Andrea


    . A common procedure in the latter approach is the use of empirical relations between TC and different petrophysical properties. Although numerous prediction equations were developed in the past five decades, none of these seem to be universally applicable for all major types of sedimentary rocks (clastics...... parameters (i.e. thermal conductivity, density, hydrogen index, sonic interval transit time, gamma-ray response, photoelectric factor) of artificial mineral assemblages consisting 15 rock-forming minerals that are used in different combinations to typify sedimentary rocks. The predictive capacity of the new...

  13. Geology, exploration status of Uruguay's sedimentary basins

    Energy Technology Data Exchange (ETDEWEB)

    Goso, C.; Santa Ana, H. de (Administracion Nacional de Combustibles, Alcohol y Portland (Uruguay))


    This article attempts to present the geological characteristics and tectonic and sedimentary evolution of Uruguayan basins and the extent to which they have been explored. Uruguay is on the Atlantic coast of South America. The country covers about 318,000 sq km, including offshore and onshore territories corresponding to more than 65% of the various sedimentary basins. Four basins underlie the country: the Norte basin, the Santa Lucia basin, the offshore Punta del Este basin, and the offshore-onshore Pelotas-Merin basin. The Norte basin is a Paleozoic basin while the others are Mesozoic basins. Each basin has been explored to a different extent, as this paper explains.

  14. Building a Bridge to Deep Time: Sedimentary Systems Across Timescales (United States)

    Romans, B.; Castelltort, S.; Covault, J. A.; Walsh, J. P.


    It is increasingly important to understand the complex and interdependent processes associated with sediment production, transport, and deposition at timescales relevant to civilization (annual to millennial). However, predicting the response of sedimentary systems to global environmental change across a range of timescales remains a significant challenge. For example, a significant increase in global average temperature at the Paleocene-Eocene boundary (55.8 Ma) is interpreted to have occurred over millennial timescales; however, the specific response of sedimentary systems (e.g., timing and magnitude of sediment flux variability in river systems) to that forcing is debated. Thus, using such environmental perturbations recorded in sedimentary archives as analogs for ongoing/future global change requires improved approaches to bridging across time. Additionally, the ability to bridge timescales is critical for addressing other questions about sedimentary system behavior, including signal propagation and signal versus ';noise' in the record. The geologic record provides information that can be used to develop a comprehensive understanding of process-response behavior at multiple timescales. The geomorphic ';snapshot' of present-day erosional and depositional landscapes can be examined to reconstruct the history of processes that created the observable configurations. Direct measurement and monitoring of active processes are used to constrain conceptual and numerical models and develop sedimentary system theory. But real-time observations of active Earth-surface processes are limited to the very recent, and how such processes integrate over longer timescales to transform into strata remains unknown. At longer timescales (>106 yr), the stratigraphic record is the only vestige of ancient sedimentary systems. Stratigraphic successions contain a complex record of sediment deposition and preservation, as well as the detrital material that originated in long since denuded

  15. Esophageal Cancer in Canada: Trends according to Morphology and Anatomical Location

    Directory of Open Access Journals (Sweden)

    Michael C Otterstatter


    Full Text Available BACKGROUND: Esophageal adenocarcinoma has one of the fastest rising incidence rates and one of the lowest survival rates of any cancer type in the Western world. However, in many countries, trends in esophageal cancer differ according to tumour morphology and anatomical location. In Canada, incidence and survival trends for esophageal cancer subtypes are poorly known.

  16. Petroleum prospectivity of the Canada Basin, Arctic Ocean (United States)

    Grantz, A.; Hart, P.E.


    Reconnaissance seismic reflection data indicate that Canada Basin is a remnant of the Amerasia Basin of the Arctic Ocean that lies south of the Alpha-Mendeleev Large Igneous Province, which was constructed on the northern part of the Amerasia Basin between about 127 and 89-75 Ma. Canada Basin is filled with Early Jurassic to Holocene detritus from the Mackenzie River system, which drains the northern third of interior North America, with sizable contributions from Alaska and Northwest Canada. Except for the absence of a salt- and shale-bearing mobile substrate Canada Basin is analogous to the Mississippi Delta and the western Gulf of Mexico. Canada Basin contains about 7 to >14 km of sediment beneath the Mackenzie Prodelta on the southeast, 6 to 7 km of sediment beneath the abyssal plain on the west, and roughly 5 or 6 million cubic km of sediment. About three fourths of the basin fill generates low amplitude seismic reflections, interpreted to represent hemiplegic deposits, and a fourth of the fill generates interbedded lenses to extensive layers of moderate to high amplitude reflections interpreted to represent unconfined turbidite and amalgamated channel deposits. Extrapolation from Arctic Alaska and Northwest Canada suggests that three fourths of the section in Canada Basin may contain intervals of hydrocarbon source rocks and the apparent age of the basin suggests that it contains three of the six stratigraphic intervals that together provided >90?? of the World's discovered reserves of oil and gas.. Worldwide heat flow averages suggest that about two thirds of Canada Basin lies in the oil or gas window. At least five types of structural or stratigraphic features of local to regional occurrence offer exploration targets in Canada Basin. These consist of 1) a belt of late Eocene to Miocene shale-cored detachment folds containing with at least two anticlines that are capped by beds with bright spots, 2) numerous moderate to high amplitude reflection packets

  17. Traditional Chinese medicine education in Canada. (United States)

    Du, Huan-bin


    The history of education and legislation of traditional Chinese medicine (TCM) and acupuncture in Canada is short. The first school of TCM opened its door to the general public in Canada in 1985 and the first legislation of acupuncture was introduced in Alberta, Canada in 1988. Currently, TCM and/or acupuncture have been regulated in five provinces in Canada. The legislation and regulation, as well as education of TCM and acupuncture vary among the five provinces in Canada. Opportunities and challenges facing TCM education exist simultaneously. Strategies are proposed to develop an international standard for TCM education in Canada, and possibly in other English speaking countries as well.

  18. Identification of thick sedimentary plains north of Hellas (United States)

    Salese, Francesco; Mangold, Nicolas; Ansan, Veronique; Carter, John; Ody, Anouck; Poulet, François; Ori, Gian Gabriele


    Understanding the origin and timing of intercrater plains is crucial to understand the Martian history in relation with endogenic and/or exogenic cycles. Intercrater plains north of Hellas basin on Mars are thought to have hosted different sedimentary environments during the Late Noachian/Early Hesperian, and they offer a well-preserved insight into the regional geological history of Mars. Our new geologic mapping of the intercrater plains north of Hellas Basin is based on the rich data set from MRO and Mars Express and provides new insights into the region's geological history. These findings appear to constrain the interpretation of the nature and age of intercrater plains in this region, although we acknowledge that for example the source of the sedimentary deposits must be subject to further analysis. The northern part of Hellas basin displays topographically flat area, which was characterized during the Late Noachian by sedimentary deposition and later, in the Late Hesperian, by fissural volcanism. The map and crater retention ages enable us to interpret the geologic history of the region. The stratigraphically lower unit is represented by crustal outcrops. Across most of the region, the sedimentary unit covers the basement and is eroded into mesas, erosional windows and perched by fresh craters. Intercrater plains' sedimentary deposits north of Hellas display horizontal light-toned layered rich in Fe/Mg-phyllosilicates and local crossbedding stratification. The Noachian sedimentary deposits of the intercrater plains north of Hellas are locally covered by Hesperian lava flows, showing that intercrater plains are sedimentary and volcanic in origin. We found different erosional (regional and local) surfaces, at HiRISE scale inside sediments due to local erosional windows and at CTX scale we found two important regional erosional surfaces. The oldest between crustal outcrops and sediments, which is likely Middle Noachian in age and the youngest between sediments

  19. Sedimentary exhalative (sedex) zinc-lead-silver deposit model (United States)

    Emsbo, Poul; Seal, Robert R.; Breit, George N.; Diehl, Sharon F.; Shah, Anjana K.


    This report draws on previous syntheses and basic research studies of sedimentary exhalative (sedex) deposits to arrive at the defining criteria, both descriptive and genetic, for sedex-type deposits. Studies of the tectonic, sedimentary, and fluid evolution of modern and ancient sedimentary basins have also been used to select defining criteria. The focus here is on the geologic characteristics of sedex deposit-hosting basins that contain greater than 10 million metric tons of zinc and lead. The enormous size of sedex deposits strongly suggests that basin-scale geologic processes are involved in their formation. It follows that mass balance constraints of basinal processes can provide a conceptual underpinning for the evaluation of potential ore-forming mechanisms and the identification of geologic indicators for ore potential in specific sedimentary basins. Empirical data and a genetic understanding of the physicochemical, geologic, and mass balance conditions required for each of these elements are used to establish a hierarchy of quantifiable geologic criteria that can be used in U.S. Geological Survey national assessments.  In addition, this report also provides a comprehensive evaluation of environmental considerations associated with the mining of sedex deposits.

  20. Evidence for a small bacterial contribution to sedimentary organic carbon

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Hartgers, W.A.; Requejo, A.G.; Allan, J.; Hayes, J.M.; Leeuw, J.W. de


    Because their molecular signatures are often prominent in extracts of sediments, bacteria are thought to be important contributors to petroleum source beds. It has been shown recently, however, that abundances of biomarkers do not always reflect relative contributions to sedimentary organic carbon (

  1. Stability of IRSL signals from sedimentary K-feldspar samples

    DEFF Research Database (Denmark)

    Thomsen, Kristina Jørkov; Murray, A.S.; Jain, Mayank


    for potassium-rich sedimentary feldspars. We show that the natural post-IR IRSL (pIRIR) signal from a 3.6 Ma old sample is in apparent saturation on a laboratory generated dose response curve, i.e. it does not show detectable fading in nature although a low fading rate is observed on laboratory time scales. We...

  2. Manganese micronodules: A possible indicator of sedimentary environments

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.

    .3%), TiO sub(2) (0.30%), SiO sub(2) (2.7%) and rare earth element (Sigma 522 ppm) contents compared to surface and buried macronodules. Micronodule abundance, size and composition depend on the redox characteristics of the sedimentary environment and can...


    Directory of Open Access Journals (Sweden)

    I. A. Larionov


    Full Text Available The results of investigations of the deformation process in the near surface sedimentary rocks, which has been carried out in a seismically active region of Kamchatka peninsular since 2007,are presented. The peculiarity of the experiments on the registration of geodeformations is the application of a laser deformograph-interferometer constructed according to the Michelson interferometer scheme.

  4. Early Archaean sedimentary basins: depositional environment and hydrothermal systems :

    NARCIS (Netherlands)

    Vries, Sjoukje Tsjitske de


    The topic of this thesis is the Early Archaean environment and hydrothermal systems in the Barberton Greenstone Belt (BGB) in South Africa, and the Coppin Gap Greenstone Belt (CGGB) in the Pilbara, Australia. Focus within these greenstone belts is on the ~3.45-3.42 Ga Buck Ridge volcano-sedimentary

  5. Evolution of sedimentary rock formation of a rock association level (United States)

    Kuznetsov, V. G.


    The evolution of sedimentary rock formation of a highly organized level (paragenetic rock associations) is more complex than that of a poorly organized level (rocks). Subjacent rock associations are established for the entire geological evolution of the Earth: they varied in time and were obsolescent or, in contrast, nascent and momentary. A certain cyclicity of evolution is identified along with directed changes.

  6. Developing Canada`s climate change strategy : electricity sector table

    Energy Technology Data Exchange (ETDEWEB)

    Castellan, A. [Ontario Hydro, Toronto, ON (Canada)


    Canada`s climate change strategy has been the focus of extensive consultation processes whose objective is to provide recommendations to federal and provincial ministers by the end of 1999. They are also designed to study the impact, the cost and the benefits of implementation of the Kyoto Protocol and to develop immediate actions to provide early reductions in CO{sub 2} emissions. The development of long-term actions that will result in sustained greenhouse gas (GHG) reductions is also on the agenda. The role of the Electricity Sector Table is to determine the contribution of GHG emissions by power generation, transmission and distribution elements as well as by electricity and cogeneration industries. The contribution of GHG emissions by renewable energy is also being studied. One of the recommended early actions is that the federal government should include solution gas as a qualifying fuel in Class 43.1 of the Income Tax Act to provide incentives to produce electricity from waste solution gas in fossil fuel production. Natural Resources Canada predicts that GHG emissions from the electricity sector will have increased from 94 MT in 1990 to 146 MT by 2020. The current sources of power generation in Canada are as follows: hydroelectric (65 per cent), nuclear (15 per cent), coal (15 per cent), and other (5 per cent).

  7. Structural development of an Archean Orogen, Western Point Lake, Northwest Territories (United States)

    Kusky, Timothy M.


    The Point Lake orogen in the central Archean Slave Province of northwestern Canada preserves more than 10 km of structural relief through an eroded antiformal thrust stack and deeper anastomosing midcrustal mylonites. Fault restoration along a 25 km long transect requires a minimum of 69 km slip and 53 km horizontal shortening. In the western part of the orogen the basal decollement places mafic plutonic/volcanic rocks over an ancient tonalitic gneiss complex. Ten kilometers to the east in the Keskarrah Bay area, slices of gneiss unroofed on brittle thrusts shed molasse into several submerged basins. Conglomerates and associated thinly bedded sedimentary rocks are interpreted as channel, levee, and overbank facies of this thrust-related sedimentary fan system. The synorogenic erosion surface at the base of the conglomerate truncates premetamorphic or early metamorphic thrust faults formed during foreland propagation, while other thrusts related to hinterland-progressing imbrication displace this unconformity. Tightening of synorogenic depositional troughs resulted in the conglomerates' present localization in synclines to the west of associated thrust faults and steepening of structural dips. Eastern parts of the orogen consist of isoclinally folded graywackes composed largely of Mutti and Ricci-Lucchi turbidite facies B, C, and D, interpreted as submarine fan deposits eroded from a distant volcanic arc. Thrust faults in the metasedimentary terrane include highly disrupted slate horizons with meter-scale duplex structures, and recrystallized calcmylonites exhibiting sheath folds and boudin trains with very large interboudin distances. The sequence of fabric development and the overall geometry of this metasedimentary terrane strongly resembles younger forearc accretionary prisms. Conditions of deformation along the thrusts parallel the regional metamorphic zonation: amphibolite facies in the basal decollement through greenschist facies shear zones to cataclastic

  8. Numero Special: La Communication Technique au Canada. (United States)

    Harris, Randy; Russell, Pamela


    Introduces (in the French language) a special issue on technical communication in Canada. Describes aspects of employment, academia, organizations, conferences, and journals in the field of technical communication in Canada. (SR)

  9. Fire - caribou - winter range relationships in northern Canada


    Thomas, D C; S.J. Barry; G. Alaie


    We needed data on temporal changes in caribou forages after fire and relative use of age-classes of forests by caribou to help devise a fire suppression priority strategy for caribou winter range in north-central Canada. Consequently, from 1983 through 1986, we estimated the abundance of vegetation and relative use by caribou at 197 sites in western and eastern study areas on the winter range of the Beverly herd of caribou {Rangifer tarandus). Species of lichens attained peak biomass at diffe...

  10. Unique Measles Virus in Canada

    Centers for Disease Control (CDC) Podcasts


    Dr. Shelley Deeks, chief of communicable diseases at Public Health Ontario, discusses a measles outbreak in Canada.  Created: 8/24/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 8/24/2017.

  11. Canada-U.S. Relations (United States)


    56 RBC Financial Group, Daily Forex Fundamentals, February 27, 2009. [ analysis/daily- forex -fundamentals/canada%27s-fourth%11quarter-current-account-moves-into-deficit-after-nine-years- of-surpluses

  12. Teaching Composition Theory in Canada. (United States)

    Graves, Roger


    Describes one teacher's experience of teaching composition theory on the graduate level at a Canadian university. Explains that there are only two rhetoric and composition programs in Canada and that, generally, Canadian universities have been slow to make the transition from neocolonialism to postcolonialism. (TB)

  13. A motogenetic classification of the sand and aleurite sediments of the Mesozoic of Western Siberia

    Energy Technology Data Exchange (ETDEWEB)

    Sidorenkov, A.I.


    A motogenetic classification is developed for terrigenous sediments with identification of the main dynamogenetic signs based on the results of a study of the output of the heavy fraction and the stability factor. Studies of the Mesozoic sedimentary series of Western Siberia made it possible to isolate the following types of sediments: currents, wave accumulation, natural alluvial sand accumulation and so on.

  14. Origin of lipid biomarkers in mud volcanoes from the Alboran Sea, western Mediterranean

    NARCIS (Netherlands)

    López-Rodríguez, C.; Stadnitskaia, A.; De Lange, G.J.; Martínez-Ruíz, F; Comas, M.; Sinninghe Damsté, J.S.


    Mud volcanoes (MVs) are the most prominentindicators of active methane/hydrocarbon venting at theseafloor on both passive and active continental margins.Their occurrence in the western Mediterranean is patent attheWest Alboran Basin, where numerous MVs develop overlayinga major sedimentary depocentr

  15. Tectonic Setting and Nature of the Provenance of Sedimentary Rocks in Lanping Mesozoic-Cenozoic Basin: Evidence from Geochemistry of Sandstones

    Institute of Scientific and Technical Information of China (English)

    李志明; 刘家军; 胡瑞忠; 何明勤; 刘玉平; 李朝阳


    The geochemical composition of sandstones in the sedimentary basin is controlled mainly by the tectonic setting of the provenance,and it is therefore possible to reveal the tectonic setting of the provenance and the nature of source rocks in terms of the geochemical composition of sandstones. The major elements,rare-earth elements and trace elements of the MesozoicCenozoic sandstones in the Lanping Basin are studied in this paper,revealing that the tectonic settings of the provenance for Mesozoic-Cenozoic sedimentary rocks in the Lanping Basin belong to a passive continental margin and a continental island arc. Combined with the data on sedimentary facies and palaeogeography,it is referred that the eastern part of the basin is located mainly at the tectonic setting of the passive continental margin before Mesozoic,whereas the western part may be represented by a continental island arc. This is compatible with the regional geology data. The protoliths of sedimentary rocks should be derived from the upper continental crust,and are composed mainly of felsic rocks,mixed with some andesitic rocks and old sediment components. Therefore,the Lanping Mesozoic-Cenozoic Basin is a typical continental-type basin. This provides strong geochemical evidence for the evolution of the paleo-Tethys and the basin-range transition.

  16. Sedimentary Response of AN Ephemeral Lake during Deglacial and Holocene Climate Evolution, Swan Lake, Southeast Idaho. (United States)

    Rosario, J. J.; Miller, D. M.; Wahl, D.; Anderson, L.; Tripati, A.; Presnetsova, L.; Oviatt, C. G.; McGeehin, J. P.; Bright, J. E.


    Perennial water systems are important ecological resources in the arid western US and provide many ecosystem services. Lakes can record fluctuations in climate (such as temperature and effective moisture) and can offer insight into regional variations in climate patterns. We studied a 7.65-m core from Swan Lake, which is a small lake and wetland complex that seasonally overflows, to examine small scale climate changes in its continuous sedimentary record. Our core is similar to that studied by Bright (1966), which exhibits two primary sedimentary facies, mud and peat, with a time span of 13.5 cal ka. The methodology includes radiocarbon dating, particle size analyses, sediment mineralogy, stable isotopes and clumped isotopes on calcium carbonate. Mud in the lower half of the core is primarily composed of clay and silt-size quartz-feldspar, but it transitions to calcium carbonate mud. Clays change from 660 to 585 cm and 350 to 220 cm in the core with an increase in kaolinite and illite upward. Ostracods in the carbonate muds are fairly uniform, indicating a mixture of wetland and lake environments from the last 5.8 ka. Similarly, summer temperatures obtained using Δ47 measurements show fluctuations in the range of 18.1 to 23.4 oC with carbonate muds generally corresponding to lower temperatures and peats to higher temperatures. We interpret muds as open water, shallow lake conditions and peats as wetlands across the floor of the ephemeral lake. If our interpretations are correct, the time from onset of the Younger Dryas to the end of the early Holocene was effectively dry, with low groundwater discharge. Similar events occurred from 4.7 to 1.0 ka and briefly at ~400 cal yr BP. Warmer climate may lead to effective moisture increase in this part of the eastern Great Basin.

  17. Main Controlling Factors on Hydrocarbon Accumulation and Distribution in Marine Sedimentary Sequences in South China

    Institute of Scientific and Technical Information of China (English)

    Cai Liguo; Zhou Yan; Bai Zhenrui


    Multiple source rock assemblages were deposited in the sedimentary provinces in South China in geologic history,and some of them were destructed by and some survived against multiple tectonic movements.Therefore,multiple sources,mixed sources,and uneven distribution of sources occurred in the marine sedimentary basins in South China during the late stage of hydrocarbon pooling.Epidiagenesis of the marine carbonate reservoirs and its modification to reservoir poroperm characteristics determined the formation and the scale of natural gas pools.The exploration practices show that the large to medium gas fields mainly occur in areas with high-quality reservoirs.Detailed study of the paleo-oil accumulations and typical oil and gas reservoirs reveals that the basins experienced multiphase superimposition and modification,leading to the distribution of the Paleozoic paleo-oil accumulations and bitumen in the peripheral areas.The phenomenon that oil and gas production concentrates in the Sichuan basin indicates that the overall sealing conditions of a basin determine the oil/gas potentials and the scale of oil and gas production.This is a critical factor controlling the accumulation and distribution of gas in the marine sequences in South China.The early oil and gas pools in the Yangtze platform left billions of bitumen in the peripheral areas due to the destruction of seals.Since the Himalayan,"late-generation and late-accumulation" gas pools represented by the gas pools in the Sichuan (四川) basin were formed in the marine sedimentary sequences in South China as a result of the change of the sealing conditions.Current gas discoveries appear to be "paleo-generation and paleo-accumulation" gas pools but actually are "late-generation and late-accumulation" gas pools.These patterns of hydrocarbon pooling clearly depict themselves in western Sichuan basin and Weiyuan (威远)gas field.It is revealed that the gas pools in the Sichuan basin were mainly formed as a result of

  18. Sedimentary organic matter variations in the Chukchi Borderland over the last 155 kyr

    Directory of Open Access Journals (Sweden)

    S. F. Rella


    Full Text Available Knowledge on past variability of sedimentary organic carbon in the Arctic Ocean is important to assess natural carbon cycling and transport processes related to global climate changes. However, the late Pleistocene oceanographic history of the Arctic is still poorly understood. In the present study we show sedimentary records of total organic carbon (TOC, C/N and CaCO3 from a piston core recovered from the northern Northwind Ridge in the far western Arctic Ocean, a region potentially sensitively responding to past variability in surface current regimes and sedimentary processes such as coastal erosion. An age model based on correlation of our CaCO3 record with the benthic δ18O stack, supplemented by lithological constraints, suggests that the piston core records paleoenvironmental changes of the last 155 kyr. According to this age model, TOC and C/N show orbital-scale increases and decreases that can be respectively correlated to the waxing and waning of large ice sheets dominating the Eurasian Arctic, suggesting advection of fine suspended matter derived from glacial erosion to the Northwind Ridge by eastward flowing intermediate water and/or surface water and sea ice during cold episodes of the last two glacial-interglacial cycles. At millennial scales, increases in TOC and C/N appear to correlate to a suite of Dansgaard-Oeschger Stadials between 120 and 40 ka before present (BP and thus seem to respond to abrupt northern hemispheric temperature changes. Between 65 and 40 ka BP, closures and openings of the Bering Strait could have additionally influenced TOC and C/N variability. CaCO3 content tends to anti-correlate with TOC and C/N on both orbital and millennial time scales, which we interpret as enhanced sediment advection from the carbonate-rich Canadian Arctic via an extended Beaufort Gyre during warm periods of the last two glacial-interglacial cycles and increased terrestrial organic carbon

  19. Wheat Production and Wheat Rust Management in Canada

    Institute of Scientific and Technical Information of China (English)

    Xue Allen G; Chi Dawn T; Zhang Shu-zhen; Li Zuo-fu


    Wheat is Canada's the largest crop with most of the production in the western Canadian Prairie Provinces of Manitoba, Saskatchewan and Alberta. There were approximately 10 million (M) hectares (hm2) seeded to wheat in Canada, including 7 M hm2 of hexaploid spring wheat (Triticum aestivum L.), 2 M hm2 of durum wheat (T. turgidum L. ssp. durum (Desf.) Husn.), and 1 M hm2 of winter wheat (T. aestivum). Within hexaploid wheat there has been diversification into a number of market classes based on different end-use quality criteria. The predominant spring bread wheat class has been the Canada Western Red Spring (CWRS) class. Historically, the disease of major concern in wheat was stem rust, caused by Puccinia graminis f. sp. tritici. The first significant stem rust resistant cultivar in Canada was Thatcher, grown extensively from 1939 until the early 1970s. Thatcher, however, was very susceptible to leaf rust, caused by Puccinia triticina. Over years, improved resistance to both stem and leaf rust was achieved with the release of cultivars with additional genes for resistance, primarily Sr2, Sr6, Sr7a, Sr9b, Lr13, Lr14a, Lr16, and Lr34. The genetic resistance has adequately controlled stem rust but leaf rust continues to cause significant loss, partially due to changes in the P. triticina population which reduced the effectiveness of resistance genes such as Lr13 and Lr16. Stripe rust on wheat, caused by Puccinia striiformis f. sp. tritici, was historically a problem under irrigation in southern Alberta, but since 2000, it has been found annually in the central Canadian prairies and southern Ontario. The genetic basis of resistance to stripe rust in most Canadian wheat cultivars has not been determined, although Yr18 provides partial resistance in many cultivars. In the future, other rust diseases, such as wheat stripe rust, or highly virulent new pathotypes of current rust pathogens, such as P. graminis f. sp. tritici race Ug-99, may pose

  20. Prediction of thermal conductivity of sedimentary rocks from well logs

    DEFF Research Database (Denmark)

    Fuchs, Sven; Förster, Andrea


    . A common procedure in the latter approach is the use of empirical relations between TC and different petrophysical properties. Although numerous prediction equations were developed in the past five decades, none of these seem to be universally applicable for all major types of sedimentary rocks (clastics...... combinations of standard geophysical well-logs. In combination with a feasible mixing-model (i.e. geometric mean model) bulk TC is computed along borehole profiles. The underlying approach was proposed by Fuchs & Förster (2014) and rests upon the detailed analysis of the interrelations between major physical...... parameters (i.e. thermal conductivity, density, hydrogen index, sonic interval transit time, gamma-ray response, photoelectric factor) of artificial mineral assemblages consisting 15 rock-forming minerals that are used in different combinations to typify sedimentary rocks. The predictive capacity of the new...

  1. Wave tectono-sedimentary processes in Tarim basin

    Institute of Scientific and Technical Information of China (English)

    JIN; Zhijun; ZHANG; Yiwei; CHEN; Shuping


    Based on the unconformities, the formation times of structures, and geological wave filtering applied to basin fills of typical wells around the Manjiaer area in the Tarim basin, the wave tectono-sedimentary processes in the Tarim Basin are discussed. The results of geological wave filtering of basin fills of typical wells show that, in time domain, the evolution of the Tarim basin was controlled by various wave processes with the periods of 740±Ma, 200±Ma, 100±Ma and 30±Ma. The analyses of basin fills, basin subsidence and unconformities show that the trends of the sedimentary facies belts, depocenters, and centers of subsidence migrated and interchanged periodically with periods of 200±Ma. These show the propagation of wave movements in space domain. The wave evolution of the Tarim basin is of significance to understanding the formation of the oil and gas reservoirs in the basin.

  2. Sedimentary Petrology: from Sorby to the globalization of Sedimentary Geology; La Petrologia Sedimentaria: desde Sorby a la globalizacion de la Geologia Sedimentaria

    Energy Technology Data Exchange (ETDEWEB)

    Alonso-Zarza, A. M.


    We describe here the most important milestones and contributions to Sedimentary Petrology compared to other geological disciplines. We define the main aim of our study and the scientific and economic interests involved in Sedimentary Petrology. The body of the paper focuses upon the historical development of this discipline from Henry Sorby's initial work until the present day. The major milestones in its history include: 1) initial descriptive works; 2) experimental studies; 3) the establishment of the different classifications of sedimentary rocks; 4) studies into facies and sedimentary environments; 5) advances in the study of diagenetic processes and their role in hydrocarbon prospection; and 6) the development of Sedimentary Geochemistry. Relationships and coincidences with Sedimentology are discussed. We go on to look at the advances that have taken place over the last 30 years, in which the study of sedimentary rocks is necessarily included in the wider field of Sedimentary Geology as a logical result of the proposal of global models of a changing Earth in which Sedimentary Geology plays a significant part. Finally we mention the notable contributions of Spanish sedimentary petrologists to this whole field of science. (Author) 120 refs.

  3. Organic sedimentary deposits in Titan's dry lakebeds: Probable evaporite (United States)

    Barnes, J.W.; Bow, J.; Schwartz, J.; Brown, R.H.; Soderblom, J.M.; Hayes, A.G.; Vixie, G.; Le, Mouelic S.; Rodriguez, S.; Sotin, C.; Jaumann, R.; Stephan, K.; Soderblom, L.A.; Clark, R.N.; Buratti, B.J.; Baines, K.H.; Nicholson, P.D.


    We report the discovery of organic sedimentary deposits at the bottom of dry lakebeds near Titan's north pole in observations from the Cassini Visual and Infrared Mapping Spectrometer (VIMS). We show evidence that the deposits are evaporitic, making Titan just the third known planetary body with evaporitic processes after Earth and Mars, and is the first that uses a solvent other than water. ?? 2011 Elsevier Inc.

  4. Preliminary catalog of the sedimentary basins of the United States (United States)

    Coleman, James L.; Cahan, Steven M.


    One hundred forty-four sedimentary basins (or groups of basins) in the United States (both onshore and offshore) are identified, located, and briefly described as part of a Geographic Information System (GIS) data base in support of the Geologic Carbon Dioxide Sequestration National Assessment Project (Brennan and others, 2010). This catalog of basins is designed to provide a check list and basic geologic framework for compiling more detailed geologic and reservoir engineering data for this project and other future investigations.

  5. Analysis of the Behavior of Sedimentary Rocks Under Impact Loading (United States)

    Millon, Oliver; Ruiz-Ripoll, Maria Luisa; Hoerth, Tobias


    In multiple engineering fields such as rock drilling or building constructions or extreme events like earthquakes or impacts, the dynamic properties of rock play an important role. A way to model these events and define measures to minimize the damage derived from these events is created by means of numerical analysis. Hence, the knowledge of the dynamic material behavior is essential for studying the effects of such a loading scenario. Solid geological materials, from the family of the sedimentary rocks, have been analyzed under quasi-static loads. However, there is a lack of knowledge when high strain rate loadings are involved. Within this context, the paper focuses on the experimental characterization of two sedimentary rocks, sandstone and limestone, under impact loading using the Hopkinson-Bar spallation and compression tests. The analysis encompasses the determination of the tensile and compressive properties as well as the comparison between the quasi-static and dynamic behavior (dynamic increase factors). The paper fills the gap of information existing about dynamic behavior of sedimentary rocks under strain rates between 100 and 5.2 × 102 s-1. Furthermore, the fragmentation under different strain rates is investigated and conclusions with respect to energy absorption capacity are drawn.

  6. Decoupled sedimentary records of combustion: Causes and implications (United States)

    Hanke, Ulrich M.; Eglinton, Timothy I.; Braun, Ana L. L.; Reddy, Christopher M.; Wiedemeier, Daniel B.; Schmidt, Michael W. I.


    Pyrogenic carbon (PyC) is a collective term for carbon-rich residues comprised of a continuum of products arising from biomass burning and fossil-fuel combustion. PyC is ubiquitous in the environment where it can be transported by wind and water before being deposited in aquatic sediments. We compare results from four different methods used to trace PyC that were applied to a high-temporal resolution sedimentary record in order to constrain changes in PyC concentrations and fluxes over the past ~250 years. We find markedly discordant records for different PyC tracers, particularly during the preindustrial age, implying different origins and modes of supply of sedimentary PyC. In addition to providing new insights into the composition of sedimentary combustion products, this study reveals that elucidation of past combustion processes and development of accurate budgets of PyC production and deposition on local to regional scales requires careful consideration of both source characteristics and transport processes.

  7. Geodynamic evolution of early Mesozoic sedimentary basins in eastern Australia (United States)

    Rosenbaum, G.; Babaahmadi, A.; Esterle, J.


    Eastern Australia is covered by a series of continental sedimentary basins deposited during the Triassic and Jurassic, but the geodynamic context of these basins is not fully understood. Using gridded aeromagnetic data, seismic reflection data, geological maps, digital elevation models, and field observations, we conducted a structural synthesis aimed at characterizing major structures and deformation style in the Triassic-Jurassic sedimentary basins of eastern Australia. Our results show evidence for four alternating episodes of rifting and contractional events during the Triassic. Two major episodes of rifting, characterized by syn-sedimentary steep normal faults and bimodal volcanism, resulted in the development of the Early-Middle Triassic Esk-Nymboida Rift System and the early Late Triassic Ipswich Basin. Faults in the Esk-Nymboida Rift System have been controlled by a pre-existing oroclinal structure. Each phase of rifting was followed by a contractional event, which produced folds, reverse faults and unconformities in the basins. Since the latest Late Triassic, thermal subsidence led to the deposition of continental sediments in the Clarence-Moreton Basin, which continued until the Early Cretaceous. We suggest that the geodynamic control on the alternating episodes of rifting and contraction during the Triassic in eastern Australia was ultimately related to plate boundary migration and switches between trench retreat and advance.

  8. Optimization of Well Configuration for a Sedimentary Enhanced Geothermal Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Mengnan; Cho, JaeKyoung; Zerpa, Luis E.; Augustine, Chad


    The extraction of geothermal energy in the form of hot water from sedimentary rock formations could expand the current geothermal energy resources toward new regions. From previous work, we observed that sedimentary geothermal reservoirs with relatively low permeability would require the application of enhancement techniques (e.g., well hydraulic stimulation) to achieve commercial production/injection rates. In this paper we extend our previous work to develop a methodology to determine the optimum well configuration that maximizes the hydraulic performance of the geothermal system. The geothermal systems considered consist of one vertical well doublet system with hydraulic fractures, and three horizontal well configurations with open-hole completion, longitudinal fractures and transverse fractures, respectively. A commercial thermal reservoir simulation is used to evaluate the geothermal reservoir performance using as design parameters the well spacing and the length of the horizontal wells. The results obtained from the numerical simulations are used to build a response surface model based on the multiple linear regression method. The optimum configuration of the sedimentary geothermal systems is obtained from the analysis of the response surface model. The proposed methodology is applied to a case study based on a reservoir model of the Lyons sandstone formation, located in the Wattenberg field, Denver-Julesburg basin, Colorado.

  9. DOE workshop: Sedimentary systems, aqueous and organic geochemistry

    Energy Technology Data Exchange (ETDEWEB)


    A DOE workshop on sedimentary systems, aqueous and organic geochemistry was held July 15-16, 1993 at Lawrence Berkeley Laboratory. Papers were organized into several sections: Fundamental Properties, containing papers on the thermodynamics of brines, minerals and aqueous electrolyte solutions; Geochemical Transport, covering 3-D imaging of drill core samples, hydrothermal geochemistry, chemical interactions in hydrocarbon reservoirs, fluid flow model application, among others; Rock-Water Interactions, with presentations on stable isotope systematics of fluid/rock interaction, fluid flow and petotectonic evolution, grain boundary transport, sulfur incorporation, tracers in geologic reservoirs, geothermal controls on oil-reservoir evolution, and mineral hydrolysis kinetics; Organic Geochemistry covered new methods for constraining time of hydrocarbon migration, kinetic models of petroleum formation, mudstones in burial diagenesis, compound-specific carbon isotope analysis of petroleums, stability of natural gas, sulfur in sedimentary organic matter, organic geochemistry of deep ocean sediments, direct speciation of metal by optical spectroscopies; and lastly, Sedimentary Systems, covering sequence stratigraphy, seismic reflectors and diagenetic changes in carbonates, geochemistry and origin of regional dolomites, and evidence of large comet or asteroid impacts at extinction boundaries.

  10. Congenital anomalies surveillance in Canada. (United States)

    Lowry, R Brian


    Congenital anomalies (CA) are present in approximately 3% of all newborn babies and account for about 12% of paediatric hospital admissions. They represent an important public health problem. Surveillance is especially important so that preventive measures such as folic acid fortification can be properly assessed without resorting to a series of ad hoc studies. Canada's surveillance of CAs is weak, with only Alberta and British Columbia having established sytems. Most provinces have perinatal systems but their CA data are incomplete and they do not capture terminations of pregnancy. The same is true of the Public Health Agency of Canada's system. A new system, the Fetal Alert Network, has been proposed for Ontario, which represents a start but will require additional sources of ascertainment if it is to be a truly population-based system for Ontario.

  11. Member 1 of Yongji Formation (Ey1) sedimentary characteristics and its origin analysis in Yitong Graben

    Institute of Scientific and Technical Information of China (English)


    Ey1 has the unique desultory-weak or gap seismic reflection structure as its one of the most important characteristics. It is very important to clarify sedimentary characteristics and its origin for Yitong Graben and its sedimentary facies and tectonic evolution. On the basis of the research of core analyses, well logging data analyses, sedimentary facies analyses and seismic reflection structure analyses, the authors have concluded the sedimentary characteristics of Ey1, and have carried out Ey1 sedimentary environments and its origin. The result shows that Ey1 desultory-weak or gap seismic reflection may be a series of small scale secondary sediment fans superimposition.

  12. Sequence associations of sedimentary facies in continental basins and their applications to palaeogeographic mapping

    Institute of Scientific and Technical Information of China (English)

    TANG Hua-feng; CHENG Ri-hui; KONG Qing-ying; BAI Yun-feng; YU Ming-feng


    According to the characteristics of sedimentary facies and their vertical associations, sequence association of sedimentary facies can be divided into 2 types and 28 subtypes. The first type (type A) is a sedimentary sequence without volcanic rocks, including 18 subtypes. The second type (type B) is a volcanogenic succession including 10 subtypes.Each subtype may reflect certain filling condition under certain sedimentary environment. Time and space distribution of different types of sequence associations can reflect tectonics that controlled the basin evolution, sedimentary environments and palaeogeography.

  13. Canada's family violence initiative: partnerships


    Scott Elaine


    Under Canada's four-year, $136 million Family Violence Initiative, the federal government is calling upon all Canadians to work in partnerships towards the elimination of family violence - child abuse, violence against women, and elder (senior) abuse. Family violence is a complex problem and requires the efforts of all Canadians to resolve it. One of the key themes of the Initiative - a multidisciplinary approach to the problem of family violence - is reflected in the selection and developmen...

  14. China, Canada Strengthen Energy Cooperation

    Institute of Scientific and Technical Information of China (English)


    @@ China and Canada released a joint statement to work together to promote the bilateral cooperation in the oil and gas sector in lateJanuary when Canadian Prime Minister Paul Martin paid a state visit to China. Encouraging respective enterprises to expand commercial partnership, the two nations have agreed to take on the energy sector - oil and gas, nuclear energy,energy efficiency and cleaner energy - as "priority areas of long-term mutual cooperation".

  15. Indigenous Educational Attainment in Canada

    Directory of Open Access Journals (Sweden)

    Catherine E. Gordon


    Full Text Available In this article, the educational attainment of Indigenous peoples of working age (25 to 64 years in Canada is examined. This diverse population has typically had lower educational levels than the general population in Canada. Results indicate that, while on the positive side there are a greater number of highly educated Indigenous peoples, there is also a continuing gap between Indigenous and non-Indigenous peoples. Data also indicate that the proportion with less than high school education declined, which corresponds with a rise of those with a PSE; the reverse was true in 1996. Despite these gains, however, the large and increasing absolute numbers of those without a high school education is alarming. There are intra-Indigenous differences: First Nations with Indian Status and the Inuit are not doing as well as non-Status and Métis peoples. Comparisons between the Indigenous and non-Indigenous populations reveal that the documented gap in post-secondary educational attainment is at best stagnant. Out of the data analysis, and based on the history of educational policy, we comment on the current reform proposed by the Government of Canada, announced in February of 2014, and propose several policy recommendations to move educational attainment forward.

  16. Chlorine isotope behavior during prograde metamorphism of sedimentary rocks (United States)

    Selverstone, Jane; Sharp, Zachary D.


    Chlorine stable isotope compositions of two sedimentary sequences and their metamorphic equivalents were measured in order to study fractionation effects during prograde metamorphism and devolatilization. Protoliths (n = 25) were collected from a 50 m section of Triassic fluvial and playa-lake strata and Jurassic (Liassic) marine black shales in a well-characterized quarry. Low greenschist to middle amphibolite facies equivalents (n > 80) were collected from the Glarus Alps, Urseren Zone, and Lucomagno region. Bulk δ37Cl values are constant within individual sedimentary layers, but vary from -2.0 to + 2.4 ‰ in Triassic rocks and from -3.0 to 0‰ in the black shales. Dolomitic and gypsiferous samples have positive δ37Cl values, but marls and shales are isotopically negative. Bulk Cl contents show only small declines during the earliest stages of metamorphism. Metamorphic equivalents of the Triassic and Liassic protoliths record the same overall ranges in δ37Cl as their protoliths. Samples with highly correlated bulk compositions but different metamorphic grade show no statistically significant difference in δ37Cl. These data lead to the following conclusions: (1) Terrestrial and marine sedimentary rocks display large primary heterogeneities in chlorine isotope composition. As a result, an unambiguous "sedimentary signature" does not exist in the chlorine stable isotope system. (2) No isotopic fractionation is discernable during metamorphic devolatilization, even at low temperatures. Alpine-style metamorphism thus has little to no effect on bulk chlorine isotopic compositions, despite significant devolatilization. (3) Cl is largely retained in the rocks during devolatilization, contrary to the normally assumed hydrophilic behavior of chlorine. Continuous release of mixed-volatile C-O-H fluids likely affected Cl partitioning between fluid and minerals and allowed chlorine to remain in the rocks. (4) There is no evidence for fluid communication across (meta)sedimentary

  17. Geothermal Energy Potential in Low Enthalpy Areas as a Future Energy Resource: Identifying Feasible Targets, Quebec, Canada, Study Case

    Directory of Open Access Journals (Sweden)

    Jacek Majorowicz


    Full Text Available Heat flow of the sedimentary succession of the Eastern Canada Sedimentary Basins varies from 40 mW/m2 close to the exposed shield in the north to high 60–70 mW/m2 in the southwest–northeast St. Lawrence corridor. As high fluid flow rates are required for a successful geothermal application, the most important targets are deep existing permeable aquifers rather than hard rock, which would need to be fracked. Unfortunately, the ten most populated Québec urban centers are in the areas where the Grenville (Canadian Shield is exposed or at shallow depths with sedimentary cover where temperatures are 30 °C or less. The city of Drummondville will be the exception, as the basement deepens sharply southwest, and higher temperatures reaching >120 °C are expected in the deep Cambrian sedimentary aquifers near a 4–5-km depth. Deep under the area where such sediments could be occurring under Appalachian nappes, temperatures significantly higher than 140 °C are predicted. In parts of the deep basin, temperatures as high as 80 °C–120 °C exist at depths of 3–4 km, mainly southeast of the major geological boundary: the Logan line. There is a large amount of heat resource at such depths to be considered in this area for district heating.

  18. Suicide policy in Canada: lessons from history. (United States)

    Spiwak, Rae; Elias, Brenda; Bolton, James M; Martens, Patricia J; Sareen, Jitender


    In Canada, suicide has transitioned from being a criminal activity with much associated stigma, to being a public health concern that needs to be managed by governments and clinicians in a culturally sensitive manner. In Canada and worldwide, the social attitudes toward and legal interpretation of suicide have been dynamic. Much has been proposed in the development of suicide policy in Canada, however Canada is unique in that it remains one of the only industrialized countries without a national suicide prevention strategy. The current article provides a critical review of the history of suicide in Canada, as well as an appraisal of Canadian suicide prevention policies and key government and political milestones that have impacted suicide policy. Current activity regarding a national suicide prevention strategy in Canada is discussed, as well as potential options for clinician involvement.

  19. Tectonics of Chukchi Sea Shelf sedimentary basins and its influence on petroleum systems (United States)

    Agasheva, Mariia; Antonina, Stoupakova; Anna, Suslova; Yury, Karpov


    The Chukchi Sea Shelf placed in the East Arctic offshore of Russia between East Siberian Sea Shelf and North Slope Alaska. The Chukchi margin is considered as high petroleum potential play. The major problem is absence of core material from drilling wells in Russian part of Chukchi Shelf, hence strong complex geological and geophysical analyses such as seismic stratigraphy interpretation should be provided. In addition, similarity to North Slope and Beaufort Basins (North Chukchi) and Hope Basin (South Chukchi) allow to infer the resembling sedimentary succession and petroleum systems. The Chukchi Sea Shelf include North and South Chukchi Basins, which are separated by Wrangel-Herald Arch and characterized by different opening time. The North Chukchi basin is formed as a general part of Canada Basin opened in Early Cretaceous. The South Chukchi Basin is characterized by a transtensional origin of the basin, this deformation related to motion on the Kobuk Fault [1]. Because seismic reflections follow chronostratigraphic correlations, it is possible to achieve stratigraphic interpretation. The main seismic horizons were indicated as: PU, JU, LCU, BU, mBU marking each regional unconformities. Reconstruction of main tectonic events of basin is important for building correct geological model. Since there are no drilling wells in the North and South Chukchi basins, source rocks could not be proven. Referring to the North Chukchi basin, source rocks equivalents of Lower Cretaceous Pebble Shale Formation, Lower Jurassic Kingdak shales and Upper Triassic Shublik Formation (North Slope) is possible exhibited [2]. In the South Chukchi, it is possible that Cretaceous source rocks could be mature for hydrocarbon generation. Erosions and uplifts that could effect on hydrocarbon preservation was substantially in Lower Jurassic and Early Cretaceous periods. Most of the structures may be connected with fault and stratigraphy traps. The structure formed at Wrangel-Herald Arch to

  20. Radon and its decay product activities in the magmatic area and the adjacent volcano-sedimentary Intrasudetic Basin

    Directory of Open Access Journals (Sweden)

    D. Tchorz


    Full Text Available In the magmatic area of Sudetes covering the Karkonosze granite and adjacent volcano-sedimentary Intrasudetic Basin a study of atmospheric radon activity was performed by means of SSNTD Kodak LR-115. The study was completed by gamma spectrometric survey of eU and eTh determined by gamma activity of radon decay products 214Bi and 208Tl respectively. In the case of the western part of the Karkonosze granite area the radon decay products activity in the granitic basement was found to be as high as 343 Bq/kg for 214Bi and 496 Bq/kg for 208Tl respectively. Atmospheric radon content measured by means of Kodak LR115 track detector at the height of 1.5 m was found as high as 70 Bq/m3 in the regions, where no mining activities took place. However in the eastern part of the granitic massif in the proximity of abandoned uranium mine atmospheric radon content was found to be 6000 Bq/m3. In the case of sedimentary basin where sedimentary sequence of Carboniferous rocks has been penetrated by younger gases and fluids of volcanic origin uranium mineralization developed. The region known from its CO2 outburst during coal mining activity is characterized by good ventilation of the uranium enriched geological basement resulting in increased atmospheric radon activity being in average 72 Bq/m3. In the vicinity of coal mine tailing an increase up to 125 Bq/m3 can be observed. Seasonal variations of atmospheric radon content are influenced in agricultural areas by cyclic cultivation works (plough on soils of increased uranium content and in the case of post-industrial brownfields varying rates of radon exhalation from tailings due to different meteorological conditions.

  1. Elemental and Sm-Nd isotopic geochemistry on detrital sedimentary rocks in the Ganzi-Songpan block and Longmen Mountains

    Institute of Scientific and Technical Information of China (English)

    CHEN Yuelong; LIU Fei; ZHANG Hongfei; NIE Lanshi; JIANG Liting


    Systematic results of major and trace element geochemistry and Sm-Nd isotopic geochemistry on detrital sedimentary rocks of Precambrian to Triassic in the Ganzi-Songpan block and Longmen Mountains are presented. The rocks are classified into greywaekes or feldspar sandstones,grains of which are the mixtures of mafic rocks, felsic rocks,and quartz + calcite. Total rare earth elements (REE) contents of the rocks increase gradually and negative Eu anomalies become more obvious from Precambrian to Triassic, which may indicate intensifying crustal anatexis. Tectonic setting was stable during the Late Paleozoic, the refore there are obvious negative Ce anomalies. Nd model ages are between 1.6 Ga and 2.4 Ga, which are very similar to those of the Yangtze croton, South Qinling and North Qinling belts and quite different from those of the North China craton. There-fore, provenance of the sedimentary rocks in the Ganzi-Songpan block and Longmen Mountains was the Yangtze craton and/or the Qinling orogen, which evolved on the basis of the Yangtze craton. The correlation between provenances and tectonostratigraphic strata of the western Yangtze craton shows that the source materials should be primarily from Neoproterozoic. Secondary sources were Archean and Paleoproterozoic strata. Triassic clastic sedimentary rocks contain Late Paleozoic mantle-derived materials, represented by the Emeishan Permian flood basalts. Spatial distribution of initial Nd isotopic compositions indicates that denudating areas were in the east and the north and depositing areas of deep water were in the west and the south for the Ganzi-Songpan basin during Triassic.

  2. Pliocene-Quaternary contourites along the northern Gulf of Cadiz margin: sedimentary stacking pattern and regional distribution (United States)

    Llave, Estefanía; Matias, Hugo; Hernández-Molina, F. Javier; Ercilla, Gemma; Stow, Dorrik A. V.; Medialdea, Teresa


    This study reports novel findings on the Pliocene-Quaternary history of the northern Gulf of Cadiz margin and the spatiotemporal evolution of the associated contourite depositional system. Four major seismic units (P1, P2, QI and QII) were identified in the Pliocene-Quaternary sedimentary record based on multichannel seismic profiles. These are bounded by five major discontinuities which, from older to younger, are the M (Messinian), LPR (lower Pliocene revolution), BQD (base Quaternary discontinuity), MPR (mid-Pleistocene revolution) and the actual seafloor. Unit P1 represents pre-contourite hemipelagic/pelagic deposition along the northern Gulf of Cadiz margin. Unit P2 reflects a significant change in margin sedimentation when contourite deposition started after the Early Pliocene. Mounded elongated and separated drifts were generated during unit QI deposition, accompanied by a general upslope progradation of drifts and the migration of main depocentres towards the north and northwest during both the Pliocene and Quaternary. This progradation became particularly marked during QII deposition after the mid-Pleistocene (MPR). Based on the spatial distribution of the main contourite depocentres and their thickness, three structural zones have been identified: (1) an eastern zone, where NE-SW diapiric ridges have controlled the development of two internal sedimentary basins; (2) a central zone, which shows important direct control by the Guadalquivir Bank in the south and an E-W Miocene palaeorelief structure in the north, both of which have significantly conditioned the basin-infill geometry; and (3) a western zone, affected in the north by the Miocene palaeorelief which favours deposition in the southern part of the basin. Pliocene tectonic activity has been an important factor in controlling slope morphology and, hence, influencing Mediterranean Outflow Water pathways. Since the mid-Pleistocene (MPR), the sedimentary stacking pattern of contourite drifts has been

  3. Canada Education Savings Program: Annual Statistical Review 2012 (United States)

    Human Resources and Skills Development Canada, 2012


    The Canada Education Savings Program (CESP) has been an initiative of the Government of Canada since 1998. As part of the Department of Human Resources and Skills Development Canada, the program administers the Canada Education Savings Grant (CESG) and the Canada Learning Bond (CLB). These two initiatives help Canadian families save for a child's…

  4. Marking Physical Literacy or Missing the Mark on Physical Literacy? A Conceptual Critique of Canada's Physical Literacy Assessment Instruments (United States)

    Robinson, Daniel B.; Randall, Lynn


    Margaret Whitehead first introduced the concept of physical literacy over 20 years ago. Since that introduction, physical literacy has been gaining in popularity within many Western physical education and sport contexts. This is particularly true within Canada, where physical literacy has been embraced by two of the nation's most notable national…

  5. Canada's family violence initiative: partnerships

    Directory of Open Access Journals (Sweden)

    Elaine Scott


    Full Text Available Under Canada's four-year, $136 million Family Violence Initiative, the federal government is calling upon all Canadians to work in partnerships towards the elimination of family violence - child abuse, violence against women, and elder (senior abuse. Family violence is a complex problem and requires the efforts of all Canadians to resolve it. One of the key themes of the Initiative - a multidisciplinary approach to the problem of family violence - is reflected in the selection and development of projects. Activities funded by the seven federal departments and agencies involved in the Initiative emphasize partnerships with the professional, voluntary, corporate, non-government and government sectors.

  6. History of geriatrics in Canada. (United States)

    Hogan, David B


    Specialization is a pervasive movement in medicine. How specialties develop is a complex phenomenon and does not depend solely on the growth of knowledge. The history of geriatrics in Canada is presented as an example of specialization in our country. The gestation period extended over decades. Practitioners moved from partial specialization to a full-time practice in the care of older patients. Opposition to the emerging specialty was mounted by established fields of practice. The choices made by the leaders of Canadian geriatrics molded the evolution of the specialty and have contributed to its precarious status at the present time.

  7. Mineral composition of sedimentary matter in the Caspian Sea (United States)

    Lukashin, V. N.; Lisitzin, A. P.; Dara, O. M.; Kozina, N. V.; Klyuvitkin, A. A.; Novigatsky, A. N.


    Data on the mineral composition of sedimentary matter and its fluxes in the sediment system of the Caspian Sea are presented. River runoff, aerosols, particulate matter from sediment traps, and the upper layer (0-1 cm) of bottom sediments are considered. The contents of detrital minerals (quartz, albite, and K-feldspar), clay minerals (illite, chlorite, and kaolinite), and carbonates (calcite, Mg-calcite, dolomite, aragonite, and rhodochrosite) are determined. Gypsum was found in bottom sediments but is absent in the other object of the sediment system.

  8. Sedimentary Carbon Stocks: A National Assessment of Scotland's Fjords. (United States)

    Smeaton, Craig; Austin, William; Davies, Althea; Howe, John


    Coastal sediments have been shown to be globally significant repositories for carbon (C) with an estimated 126.2 Tg of C being buried annually (Duarte et al. 2005). Though it is clear these areas are important for the long-term storage of C the actual quantity of C held within coastal sediment remains largely unaccounted for. The first step to understanding the role the coastal ocean plays in the global C cycle is to quantify the C held within these coastal sediments. Of the different coastal environment fjords have been shown to be hotspots for C burial with approximately 11 % of the annual global marine carbon sequestration occurring within fjordic environments (Smith et al. 2015). Through the development of a joint geophysical and geochemical methodology we estimated that the sediment in a mid-latitude fjord holds 26.9 ± 0.5 Mt of C (Smeaton et al., 2016), with these results suggesting that Scottish mid-latitude fjords could be a significant unaccounted store of C equivalent to their terrestrial counterparts (i.e. peatlands). Through the application of the joint geophysical and geochemical methodology developed by Smeaton et al (2016) to a number of other mid-latitude fjords, we will create detailed estimations of the sedimentary C stored at these individual sites. Using these detailed C stock estimations in conjunction with upscaling techniques we will establish the first national estimation of fjordic sedimentary C stocks. The data produced will allow for the sedimentary C stocks to be compared to other national C stocks, such as the Scottish peatlands (Chapman et al. 2009) and forestry (Forestry Commission, 2016). Alongside quantifying this large unaccounted for store of C in the coastal ocean this work also lays foundations for future work to understand the role of the coastal ocean in the global C cycle. Duarte, C. M., Middelburg, J. J., and Caraco, N.: Major role of marine vegetation on the oceanic carbon cycle, Biogeosciences, 2, 1-8, doi:10.5194/bg-2

  9. The impact of sedimentary coatings on the diagenetic Nd flux (United States)

    Abbott, April N.; Haley, Brian A.; McManus, James


    Because ocean circulation impacts global heat transport, understanding the relationship between deep ocean circulation and climate is important for predicting the ocean's role in climate change. A common approach to reconstruct ocean circulation patterns employs the neodymium isotope compositions of authigenic phases recovered from marine sediments. In this approach, mild chemical extractions of these phases is thought to yield information regarding the εNd of the bottom waters that are in contact with the underlying sediment package. However, recent pore fluid studies present evidence for neodymium cycling within the upper portions of the marine sediment package that drives a significant benthic flux of neodymium to the ocean. This internal sedimentary cycling has the potential to obfuscate any relationship between the neodymium signature recovered from the authigenic coating and the overlying neodymium signature of the seawater. For this manuscript, we present sedimentary leach results from three sites on the Oregon margin in the northeast Pacific Ocean. Our goal is to examine the potential mechanisms controlling the exchange of Nd between the sedimentary package and the overlying water column, as well as the relationship between the εNd composition of authigenic sedimentary coatings and that of the pore fluid. In our comparison of the neodymium concentrations and isotope compositions from the total sediment, sediment leachates, and pore fluid we find that the leachable components account for about half of the total solid-phase Nd, therefore representing a significant reservoir of reactive Nd within the sediment package. Based on these and other data, we propose that sediment diagenesis determines the εNd of the pore fluid, which in turn controls the εNd of the bottom water. Consistent with this notion, despite having 1 to 2 orders of magnitude greater Nd concentration than the bottom water, the pore fluid is still <0.001% of the total Nd reservoir in the

  10. In situ NMR analysis of fluids contained in sedimentary rock (United States)

    de Swiet TM; Tomaselli; Hurlimann; Pines


    Limitations of resolution and absorption in standard chemical spectroscopic techniques have made it difficult to study fluids in sedimentary rocks. In this paper, we show that a chemical characterization of pore fluids may be obtained in situ by magic angle spinning (MAS) nuclear magnetic resonance (NMR), which is normally used for solid samples. 1H MAS-NMR spectra of water and crude oil in Berea sandstone show sufficient chemical shift resolution for a straightforward determination of the oil/water ratio. Copyright 1998 Academic Press.

  11. Canada. (United States)

    Gilham, Virginia


    Annotates 122 publications from the Canadian federal government and from 9 Canadian provinces. Topics include environmental programs and problems, gambling, crime, young offenders, health and welfare issues, use of electronic information, materials on education, employment, tourism, the North American Free Trade Agreement, and issues relating to…

  12. Regional drought-induced reduction in the biomass carbon sink of Canada's boreal forests. (United States)

    Ma, Zhihai; Peng, Changhui; Zhu, Qiuan; Chen, Huai; Yu, Guirui; Li, Weizhong; Zhou, Xiaolu; Wang, Weifeng; Zhang, Wenhua


    The boreal forests, identified as a critical "tipping element" of the Earth's climate system, play a critical role in the global carbon budget. Recent findings have suggested that terrestrial carbon sinks in northern high-latitude regions are weakening, but there has been little observational evidence to support the idea of a reduction of carbon sinks in northern terrestrial ecosystems. Here, we estimated changes in the biomass carbon sink of natural stands throughout Canada's boreal forests using data from long-term forest permanent sampling plots. We found that in recent decades, the rate of biomass change decreased significantly in western Canada (Alberta, Saskatchewan, and Manitoba), but there was no significant trend for eastern Canada (Ontario and Quebec). Our results revealed that recent climate change, and especially drought-induced water stress, is the dominant cause of the observed reduction in the biomass carbon sink, suggesting that western Canada's boreal forests may become net carbon sources if the climate change-induced droughts continue to intensify.

  13. Application of GPR in the study of shallow subsurface sedimentary architecture of Modwa spit, Gulf of Kachchh

    Indian Academy of Sciences (India)

    S B Shukla; A K Patidar; Nilesh Bhatt


    The coastline constitutes a very sensitive geomorphic domain constantly subjected to dynamic coastal processes. The study of its ever-changing physiography and stratigraphy provides a wealth of information on its history and evolution, in many cases at decadal and annual scales. The present study was carried out on the Modwa beach complex between Rawal Pir and Modwa, about 10 km east of Mandvi on the northern coast of the Gulf of Kachchh. The Modwa spit is a 7-km long WNW-ESE trending prograding amalgamated beach ridge complex that is about 0.5 km wide at its western end and 1.5 km wide at its eastern end. This Ground-Penetrating Radar (GPR) survey delineated a variety of the radar surfaces and radar facies which reflects not only large scale sedimentary architecture, but depositional facies of the beach ridge complex. These are bounding surfaces separating the radar facies outline beach ridge (br), washover (wo), coastal dune (cd) and swale (sw) depositional environments. The internal sedimentary structures like tangential, parallel, concave and convex upward stratifications could also be visualized from the GPR profiles. The architecture suggests the formation of this complex due to a combined process of eastward littoral drift of locally derived sediments and its onshore deposition by storms and eolian activities.

  14. Kalahari salt pans as sedimentary archives for reconstruction of Quaternary environments (United States)

    Schüller, Irka; Belz, Lukas; Wilkes, Heinz; Wehrmann, Achim


    Environmental changes in southern Africa come along with variations in atmospheric and oceanic circulation as well as anthropogenic caused landuse changes. The reconstruction of the paleoenvironment is complicated by the fact that continuous geoarchives are rare in the semiarid to arid parts of this region. In the south-western Kalahari lacustrine systems with constant sedimentary records are absent due to the low precipitation. Salt pans are common geomorphological structures in the Kalahari which are temporarily flooded during summer season when isolated showers occur in their local catchment area. So, they are potential archives preserving environmental signals in phases of sedimentation. However, marginal dunes on their leeward sides represent phases of deflation. The principle processes in salt pan formation are complex and so far under discussion. Our study follows a multidisciplinary approach integrating sedimentological, geochemical and microbiological methods to understand the formation of salt pans as a prerequisite for using them as geoarchives in reconstruction of the paleoenvironmental condition during phases of sedimentation and erosion. Sediment cores from five salt pans were analysed using XRD, XRF and grain size analyses. Additionally, age models can be given for four salt pans, based on δ14C from bulk sediment TOC. As palynological material is lacking, different methods in organic geochemistry were applied (plant biomarkers, particularly leaf wax n-alkanes and n-alcohols and their stable carbon and hydrogen isotopic signatures) to reconstruct variations in local vegetation assemblages. Our results allow a better understanding of the sedimentology of salt pans and their interpretation as discontinuous archives.

  15. Sedimentary-tectonic evolution from late Palaeozoic to Triassic in south of North China block

    Energy Technology Data Exchange (ETDEWEB)

    Chen, S. [University of Petroleum, Dongying (China). Dept of Resource


    The sedimentary facies of some typical profiles as in Hancheng, Jiyuan, Denfeng and Huainan, and the characteristic of regional palaeogeography in the south of North China block were researched. The result shows that the research area had an evolution from the epeiric sea to a lake basin during Palaeozoic to Triassic. This transition was controlled by the collision progeny of Qinling orogenic belt directly. The collision began along the Shangnan-Zhenping-Tongbai line, making the south of North China block compressed and subsided, and transferred from a structural high land to an epeiric sea in Late Carboniferous. The western part of North Qinling began to uplift and became a source of terrigenous clastic sediments to North China basin. In the Permian, the compression strengthened further and the North Qinling-North Huaiyang structural belt uplifted, making the epeiric sea transits to a marginal lake basin. In the Triassic, the Qinling orogenic belt uplifted rapidly and the large scale depression lake basin developed in its north side, and the centre of the basin also transferred to the orogenic belt in the Late Triassic. 7 refs., 4 figs.

  16. Electrical resistivity dynamics beneath a fractured sedimentary bedrock riverbed in response to temperature and groundwater-surface water exchange (United States)

    Steelman, Colby M.; Kennedy, Celia S.; Capes, Donovan C.; Parker, Beth L.


    Bedrock rivers occur where surface water flows along an exposed rock surface. Fractured sedimentary bedrock can exhibit variable groundwater residence times, anisotropic flow paths, and heterogeneity, along with diffusive exchange between fractures and rock matrix. These properties of the rock will affect thermal transients in the riverbed and groundwater-surface water exchange. In this study, surface electrical methods were used as a non-invasive technique to assess the scale and temporal variability of riverbed temperature and groundwater-surface water interaction beneath a sedimentary bedrock riverbed. Conditions were monitored at a semi-daily to semi-weekly interval over a full annual period that included a seasonal freeze-thaw cycle. Surface electromagnetic induction (EMI) and electrical resistivity tomography (ERT) methods captured conditions beneath the riverbed along a pool-riffle sequence of the Eramosa River in Canada. Geophysical datasets were accompanied by continuous measurements of aqueous specific conductance, temperature, and river stage. Time-lapse vertical temperature trolling within a lined borehole adjacent to the river revealed active groundwater flow zones along fracture networks within the upper 10 m of rock. EMI measurements collected during cooler high-flow and warmer low-flow periods identified a spatiotemporal riverbed response that was largely dependent upon riverbed morphology and seasonal groundwater temperature. Time-lapse ERT profiles across the pool and riffle sequence identified seasonal transients within the upper 2 and 3 m of rock, respectively, with spatial variations controlled by riverbed morphology (pool versus riffle) and dominant surficial rock properties (competent versus weathered rock rubble surface). While the pool and riffle both exhibited a dynamic resistivity through seasonal cooling and warming cycles, conditions beneath the pool were more variable, largely due to the formation of river ice during the winter season

  17. Geology of the Nain Complex, Labrador, Canada: Occurrence of the Early Archean Supracrustals


    小宮, 剛; Komiya, Tsuyoshi; 山本, 伸次; Yamamoto, Shinji; 澤木, 佑介; 青木, 一勝; Aoki, Kazumasa


    The Hadean is the most mysterious period because no rocks andgeologic bodies are preserved except for only the zircons inWestern Australia, Canada, China and Greenland [1]. But, it is themost important period because the early evolution possibly clinchedthe earth’s history. We try to find the earliest supracrustal rocks inthe world to investigate the Hadean tectonics. As far, the oldestsupracrustal rocks are found in Akilia association in WestGreenland, Nuvvuagittuq in Quebec, and Nain Comple...

  18. Organic parasite control for poultry and rabbits in British Columbia, Canada

    Directory of Open Access Journals (Sweden)

    Turner Nancy


    Full Text Available Abstract Plants used for treating endo- and ectoparasites of rabbits and poultry in British Columbia included Arctium lappa (burdock, Artemisia sp. (wormwood, Chenopodium album (lambsquarters and C. ambrosioides (epazote, Cirsium arvense (Canada thistle, Juniperus spp. (juniper, Mentha piperita (peppermint, Nicotiana sp. (tobacco, Papaver somniferum (opium poppy, Rubus spp. (blackberry and raspberry relatives, Symphytum officinale (comfrey, Taraxacum officinale (common dandelion, Thuja plicata (western redcedar and Urtica dioica (stinging nettle.

  19. Organic parasite control for poultry and rabbits in British Columbia, Canada (United States)


    Plants used for treating endo- and ectoparasites of rabbits and poultry in British Columbia included Arctium lappa (burdock), Artemisia sp. (wormwood), Chenopodium album (lambsquarters) and C. ambrosioides (epazote), Cirsium arvense (Canada thistle), Juniperus spp. (juniper), Mentha piperita (peppermint), Nicotiana sp. (tobacco), Papaver somniferum (opium poppy), Rubus spp. (blackberry and raspberry relatives), Symphytum officinale (comfrey), Taraxacum officinale (common dandelion), Thuja plicata (western redcedar) and Urtica dioica (stinging nettle). PMID:21756341

  20. Organic parasite control for poultry and rabbits in British Columbia, Canada. (United States)

    Lans, Cheryl; Turner, Nancy


    Plants used for treating endo- and ectoparasites of rabbits and poultry in British Columbia included Arctium lappa (burdock), Artemisia sp. (wormwood), Chenopodium album (lambsquarters) and C. ambrosioides (epazote), Cirsium arvense (Canada thistle), Juniperus spp. (juniper), Mentha piperita (peppermint), Nicotiana sp. (tobacco), Papaver somniferum (opium poppy), Rubus spp. (blackberry and raspberry relatives), Symphytum officinale (comfrey), Taraxacum officinale (common dandelion), Thuja plicata (western redcedar) and Urtica dioica (stinging nettle).

  1. Eastern Canada natural gas developments

    Energy Technology Data Exchange (ETDEWEB)

    Wall, A. [Engage Energy Canada, L.P., Mississauga, ON (Canada)


    This power point presentation addressed the following topics regarding development of natural gas in eastern Canada: (1) the 18 Tcf of proven natural gas reserves at Sable Island, (2) Canadian markets benefiting from the Maritimes and Northeast Pipeline (M and NP), (3) a 20 year franchise agreement between Enbridge Gas and the government of New Brunswick, (4) the 25 year provincial franchise agreement by Sempra Atlantic Gas, and (5) Sable Island's influence on central Canada. The Sable Offshore Energy Project (SOEP) is now producing about 540,000 MMBtu/day from 6 fields. Plans for Tier 2 expansion are underway. Firm contracts for the M and NP are scheduled to transport gas from the SOEP to markets in Nova Scotia, New Brunswick, Maine and New Hampshire. Sable gas is also a potential supply for the Quebec market. Gaz Metropolitain and Enbridge have proposed to build the Cartier Pipeline from the Quebec/New Brunswick border to Quebec City. It is unlikely that Sable Island supply will directly serve the Ontario market. Canadian customers for Sable gas and M and NP service include pulp and paper companies, oil refineries, power generators and local distribution companies (LDC), with the majority of demand coming form the electric power industry. tabs., figs.

  2. The Pliocene initiation and Early Pleistocene volcanic disruption of the palaeo-Gediz fluvial system, Western Turkey

    NARCIS (Netherlands)

    Maddy, D.; Demir, T.; Bridgland, D.R.; Veldkamp, A.; Stemerdink, C.; Schriek, van der T.; Schreve, D.


    In this paper, we report our latest observations concerning a Pliocene and Early Pleistocene record from Western Turkey. The sedimentary sequence described comprises the fluvial deposits of an Early Pleistocene palaeo-Gediz river system and its tributaries prior to the onset of volcanism around Kula

  3. Reconstructing Early Pleistocene (1.3 Ma) terrestrial environmental change in western Anatolia: Did it drive fluvial terrace formation?

    NARCIS (Netherlands)

    Veldkamp, A.; Candy, I.; Jongmans, A.G.; Maddy, D.; Demir, T.; Schoorl, J.M.; Schreve, D.; Stemerdink, C.; Schriek, van der T.


    A terrestrial environmental reconstruction of an Early Pleistocene landscape from western Anatolia is presented. The basis of this reconstruction is a sedimentary stack comprising fluvial and colluvial slope deposits. Contained within this stack is a sequence comprising two massive laminar calcretes

  4. Consumption and diffusion of dissolved oxygen in sedimentary rocks. (United States)

    Manaka, M; Takeda, M


    Fe(II)-bearing minerals (e.g., biotite, chlorite, and pyrite) are a promising reducing agent for the consumption of atmospheric oxygen in repositories for the geological disposal of high-level radioactive waste. To estimate effective diffusion coefficients (De, in m(2)s(-1)) for dissolved oxygen (DO) and the reaction rates for the oxidation of Fe(II)-bearing minerals in a repository environment, we conducted diffusion-chemical reaction experiments using intact rock samples of Mizunami sedimentary rock. In addition, we conducted batch experiments on the oxidation of crushed sedimentary rock by DO in a closed system. From the results of the diffusion-chemical reaction experiments, we estimated the values of De for DO to lie within the range 2.69×10(-11)concentration of reactive sites was about 10(-4)molm(-2) from batch experiments. In contrast, the value of reactive sites estimated from the physical surface area was about 10(-8)molm(-2), indicating that the reaction within intact rock is limited to the sites that originally existed with accessible porosity for O2(aq). This difference arises because the batch experiments used powdered samples, meaning that new sites which formed during milling were added to the original reaction sites. On the basis of these observations and interpretations, diffusion-chemical reaction experiments make it possible to determine the values of the kinetic parameter and diffusivity for an intact rock sample simultaneously. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Geochemistry of Fine-grained Sediments and Sedimentary Rocks (United States)

    Sageman, B. B.; Lyons, T. W.


    The nature of detrital sedimentary (siliciclastic) rocks is determined by geological processes that occur in the four main Earth surface environments encountered over the sediment's history from source to final sink: (i) the site of sediment production (provenance), where interactions among bedrock geology, tectonic uplift, and climate control weathering and erosion processes; (ii) the transport path, where the medium of transport, gradient, and distance to the depositional basin may modify the texture and composition of weathered material; (iii) the site of deposition, where a suite of physical, chemical, and biological processes control the nature of sediment accumulation and early burial modification; and (iv) the conditions of later burial, where diagenetic processes may further alter the texture and composition of buried sediments. Many of these geological processes leave characteristic geochemical signatures, making detrital sedimentary rocks one of the most important archives of geochemical data available for reconstructions of ancient Earth surface environments. Although documentation of geochemical data has long been a part of the study of sedimentation (e.g., Twenhofel, 1926, 1950; Pettijohn, 1949; Trask, 1955), the development and application of geochemical methods specific to sedimentary geological problems blossomed in the period following the Second World War ( Degens, 1965; Garrels and Mackenzie, 1971) and culminated in recent years, as reflected by the publication of various texts on marine geochemistry (e.g., Chester, 1990, 2000), biogeochemistry (e.g., Schlesinger, 1991; Libes, 1992), and organic geochemistry (e.g., Tissot and Welte, 1984; Engel and Macko, 1993).Coincident with the growth of these subdisciplines a new focus has emerged in the geological sciences broadly represented under the title of "Earth System Science" (e.g., Kump et al., 1999). Geochemistry has played the central role in this revolution (e.g., Berner, 1980; Garrels and Lerman

  6. Bottom-trawling along submarine canyons impacts deep sedimentary regimes (United States)

    Paradis, Sarah; Puig, Pere; Masqué, Pere; Juan-Díaz, Xènia; Martín, Jacobo; Palanques, Albert


    Many studies highlight that fish trawling activities cause seafloor erosion, but the assessment of the remobilization of surface sediments and its relocation is still not well documented. These impacts were examined along the flanks and axes of three headless submarine canyons incised on the Barcelona continental margin, where trawling fleets have been operating for decades. Trawled grounds along canyon flanks presented eroded and highly reworked surface sediments resulting from the passage of heavy trawling gear. Sedimentation rates on the upper canyon axes tripled and quadrupled its natural (i.e. pre-industrialization) values after a substantial increase in total horsepower of the operating trawling fleets between 1960 s and 1970 s. These impacts affected the upper canyon reaches next to fishing grounds, where sediment resuspended by trawling can be transported towards the canyon axes. This study highlights that bottom trawling has the capacity to alter natural sedimentary environments by promoting sediment-starved canyon flanks, and by enhancing sedimentation rates along the contiguous axes, independently of canyons’ morphology. Considering the global mechanisation and offshore expansion of bottom trawling fisheries since the mid-20th century, these sedimentary alterations may occur in many trawled canyons worldwide, with further ecological impacts on the trophic status of these non-resilient benthic communities. PMID:28233856

  7. Isolation of Geobacter species from diverse sedimentary environments (United States)

    Coaxes, J.D.; Phillips, E.J.P.; Lonergan, D.J.; Jenter, H.; Lovley, D.R.


    In an attempt to better understand the microorganisms responsible for Fe(III) reduction in sedimentary environments, Fe(III)-reducing microorganisms were enriched for and isolated from freshwater aquatic sediments, a pristine deep aquifer, and a petroleum-contaminated shallow aquifer. Enrichments were initiated with acetate or toluene as the electron donor and Fe(III) as the electron acceptor. Isolations were made with acetate or benzoate. Five new strains which could obtain energy for growth by dissimilatory Fe(III) reduction were isolated. All five isolates are gram- negative strict anaerobes which grow with acetate as the electron donor and Fe(III) as the electron acceptor. Analysis of the 16S rRNA sequence of the isolated organisms demonstrated that they all belonged to the genus Geobacter in the delta subdivision of the Proteobacteria. Unlike the type strain, Geobacter metallireducens, three of the five isolates could use H2 as an electron donor fur Fe(III) reduction. The deep subsurface isolate is the first Fe(III) reducer shown to completely oxidize lactate to carbon dioxide, while one of the freshwater sediment isolates is only the second Fe(III) reducer known that can oxidize toluene. The isolation of these organisms demonstrates that Geobacter species are widely distributed in a diversity of sedimentary environments in which Fe(III) reduction is an important process.

  8. Tectonic and sedimentary evolution of Bransfield Basin, Antarctica

    Energy Technology Data Exchange (ETDEWEB)

    Jeffers, J.D.; Thomas, M.A.; Anderson, J.B.


    The Bransfield basin is the youngest and best developed of a series of extensional marginal basins on the Pacific margin of the Antarctic Peninsular. Marine geophysical data collected over five seasons show that the back arc is segmented laterally into three subbasins separated by transform zones. These subbasins differ in width, depth, structural style, and seisimicity and are correlated with three different age segments of subducted sea floor. The distribution of principal sedimentary environments, identified from high-resolution seismic reflection data, and their associated lithofacies, seen in piston cores and surface sediment samples, is controlled largely by the tectonic segmentation of the basins. Terrigenous sediments prograde into the basin from the continent side, whereas sediment gravity-flow processes deliver volcaniclastic material from the arc to slope-base aprons and to fan lobes at the outlets of fiords. Organic-rich muds fill the deep basin; their proximity to submarine volcanic centers produces thermogenic hydrocarbons. Understanding the recent tectonic and sedimentary evolution of the Bransfield basin may help refine interpretations of the older deformed marginal basin sequences of southern South America, the Scotia Arc, and the Antarctic Peninsula.

  9. Diagenesis of sedimentary phosphorite deposits in Djebel Onk basin, Algeria

    DEFF Research Database (Denmark)

    Redjehimi, Hacène; Friis, Henrik; Boutaleb, Abdelhak

    Phosphate rocks are important economic natural resources. The sedimentary succession of Djebel Onk, which is characterised by the deposition of phosphatic formations of Late Palaeocene - Early Eocene age (Upper Thanetian-Lower Ypresian), range in age from Upper Cretaceous (Maastrichtian) to the E......Phosphate rocks are important economic natural resources. The sedimentary succession of Djebel Onk, which is characterised by the deposition of phosphatic formations of Late Palaeocene - Early Eocene age (Upper Thanetian-Lower Ypresian), range in age from Upper Cretaceous (Maastrichtian......) to the Eocene (Lutetian); this marine sequence of approximately 500m thick is overlain in discordance by a thick continental sequence of sand and clays of Miocene age, then by the Quaternary deposits. The Thanetian sequence starts with dark grey marls and pass up section to thick economic phosphorite layer...... of about 30m at Djebel Onk and which thins until it disappears northwards, the West and the South of this economic phosphorite layer generally ends by a lumachellic level. The economic phosphorite layer crops out as a NE-SW lenticular body of friable gray-brown phosphorites and consists of two phosphate...

  10. Canada's Changing Geography of Jobs and Trade. (United States)

    Kilgour, David


    Discusses the impact of globalization on the jobs and trade of Canada. Emphasizes new relationships with countries in Latin America and Africa. Notes the types of trade that Canada enjoys with these two areas and encourages expansion of business into them. (DSK)

  11. Current Trends in Leisure Sports in Canada

    Institute of Scientific and Technical Information of China (English)



    The purpose of this study was to explore the current trends in leisure sports in Canada. Based on physical activity and sport participation levels investigation conducted by Statistics Canada and the Ca-nadian Fitness and Lifestyle Research Institute,this paper provided an overview of the most recent findings on participation of leisure,sport,physical activity,and exercise of Canadians.

  12. Open Educational Resources in Canada 2015 (United States)

    McGreal, Rory; Anderson, Terry; Conrad, Dianne


    Canada's important areas of expertise in open educational resources (OER) are beginning to be built upon or replicated more broadly in all education and training sectors. This paper provides an overview of the state of the art in OER initiatives and open higher education in general in Canada, providing insights into what is happening nationally…

  13. Historical Empathy and "Canada: A People's History" (United States)

    Bryant, Darren; Clark, Penney


    In this article, we examine the CBC/Radio-Canada series, "Canada: A People's History," for its use of empathy, specifically with regard to its portrayal of Aboriginal people. We call the empathy promoted in the series, emotive empathy, and compare it to the concept of historical empathy constructed by researchers in history education. The emotive…

  14. Identifying sources, formation pathways and geological controls of methane in shallow groundwater above unconventional natural gas plays in Alberta, Canada (United States)

    Mayer, B.; Humez, P.; Nightingale, M.; Ing, J.; Kingston, A. W.; Clarkson, C.; Cahill, A.; Parker, B. L.; Cherry, J. A.; Millot, R.; Kloppmann, W.; Osadetz, K.; Lawton, D.


    With the advent of shale gas development facilitated by hydraulic fracturing it has become increasingly important to develop tracer tools to scientifically determine potential impacts of stray gases on shallow aquifers. To assess potential future impacts on shallow aquifers by leakage of natural gas from unconventional energy resource development, it is essential to establish a reliable baseline. Occurrence of methane in shallow groundwater in Alberta (Canada) between 2006 and 2014 was assessed and was ubiquitous in 186 sampled monitoring wells. Free and dissolved gas sampling and measurement approaches yielded comparable results with often low methane concentrations in shallow groundwater, but in 28 samples methane exceeded 10 mg/L in dissolved gas and 300,000 ppmv in free gas. Methane concentrations in free and dissolved gas samples were found to increase with well depth and were especially elevated in groundwater obtained from aquifers containing coal seams and shale units. Carbon isotope ratios of methane averaged -69.7 ± 11.1 ‰ in free gas and -65.6 ± 8.9 ‰ in dissolved gas. δ13C values were not found to vary with well depth or lithology indicating that the methane in Alberta groundwater was formed via a similar mechanism. The low δ13C values in concert with average δ2H values of -289 ± 44 ‰ suggest that most methane was of biogenic origin predominantly generated via CO2 reduction. This interpretation is confirmed by gas dryness parameters typically >500 due to only small amounts of ethane and a lack of propane in most samples. Novel approaches of in-situ concentration and isotope measurements for methane during drilling of a 530 m deep well yielded a mud-gas profile characterizing natural gas occurrences in the intermediate zone. Comparison with mudgas profile carbon isotope data revealed that methane in the investigated shallow groundwater in Alberta is isotopically similar to hydrocarbon gases found in 100-250 meter depths in the Western

  15. Sedimentary dynamics along the west coast of Bohai Bay, China, during the twentieth century

    DEFF Research Database (Denmark)

    Wang, Fu; Wang, Huang; Zong, Y.


    from the sediment cores, the chronology of the sediment sequences was established, from which the sedimentary history of the tidal flats was reconstructed. Results inform spatial and temporal variations in sedimentation rate along the Tianjin coast, from which sedimentary dynamics can be deduced. Two...... in this study. This study highlights the usefulness of applying both 210Pb and 137Cs dating methods. These dating methods, together with detailed sedimentary analysis, can provide valuable sedimentary evidence of coastal change and natural and human causes of change....

  16. Geochemistry of dispersed sedimentary matter and its fluxes in the water column of the Caspian Sea (United States)

    Lukashin, V. N.; Lisitzin, A. P.


    The first data on the chemical composition of dispersed matter from sedimentary traps are reported. The suspended components of sedimentary matter (amorphous silica, organic matter, carbonates, and lithogenic material, as well as Fe, Mn, and minor elements) are considered. As a result, it is shown that the intraannual variability in vertical fluxes of sedimentary matter is characterized by a seasonal increase in spring and autumn. The high fluxes of the components of sedimentary matter on the northern and southern slopes of the Derbent Basin in winter are explained by precipitation of material from the nepheloid layer that forms over the contour current.

  17. The supra-detachment tectono-sedimentary record of rifted margins: the example of the Los Barriles Basin, SE Baja California Sur. (United States)

    Masini, Emmanuel; Robin, Cécile; Geoffroy, Laurent; Strzerzynski, Pierre


    coarse conglomerates of granitic composition and overlies the previous Refugio fm. only in the Southern part of the basin with NS incisions. To the North, the Barriles fm. is replaced by the San Isidoro polymictic conglomerates with divergent paleoflows as an independent sedimentary system. These three units are syn-tectonic since they onlap the allochthon to the east, are successively tilted, indicating the occurrence of growth structures, and are deposited over the exhuming footwall. High angle faults cross cutting the detachment fault are observed in the western border of the basin. These faults control the syn-Refugio segmentation of the former basin as indicated by sedimentary process and the sourcing change. The latter Barriles fm. records the axial progradation of the Refugio's feeder fan over the opening basin. (4) The El Choro fluvial sandy fm. (post-tectonic Pleistocene) strongly incised the previous units and occurs as a major undeformed unconformity over the whole Los Barriles basin. Comparing the Los Barriles tectono-sedimentary evolution with those of other supra-detachment systems, such as those exposed in the Alps or in the Pyrenees, we can show that there are strong similarities as the progressive switching from local-lateral processes to more regional and axial sedimentary processes. A main remaining question is how the sub-aerial tectono-sedimentary evolution can be linked with the subsidence and the sedimentary evolution of the off-shore basins for which continental breakup and onset of seafloor spreading is interpreted to be of Mid-Pliocene age.

  18. Sedimentary constraints on the development of a narrow deep strait (São Sebastião Channel, SE Brazil) (United States)

    Alcántara-Carrió, Javier; Sasaki, Dalton Kei; Mahiques, Michel Michaelovitch de; Taborda, Rui; de Souza, Luiz Antonio Pereira


    The São Sebastião Channel (SSC), which separates São Sebastião Island from the continent, is a deep elongated strait on the inner shelf of the São Paulo Bight (SE Brazil). The aim of this study is to explain why it is presently sediment starved, instead of forming a tombolo. Wave data were obtained from both a WW3 model database and buoy records, and wave propagation patterns from the SWAN numerical model. Grain size trend analysis of 579 surficial sediment samples from the strait and the surrounding region served to estimate the residual transport directions. Bedload sediment transport was computed considering in situ currents and bottom sediment grain size. Moreover, six seismic profiles and one gravity core were obtained in the strait in order to evaluate the hickness of the sedimentary deposits. The geometry of the SSC (X/B=0.3, where B is the breakwater or island diameter and X is its cross-shore distance to the mainland) predicts that a tombolo should be formed, and wave patterns confirm that it is a zone sheltered from both S and NE waves. Previous studies have shown that the hydrodynamics of the SSC is controlled by wind-driven currents, which are more intense in the eastern and central sectors of the strait. The western sector is currently covered by sandy mud, whereas very coarse to fine sand prevails in the deeper eastern sector. Sediment patterns show a trend to deposition of fine sediment in the western sector of the SSC and two main depocentres located at the northern limit of the study area and at the southern mouth of the strait. Sandy mud in the western sector forms a 40-m-thick deposit close to the outer limit of Araçá Bay, whereas the remainder of the SSC is covered by a very thin layer of sandy sediments. Dominance of mud in the depositional western sector suggests low availability of sand in the area. Therefore, despite the geometry and wave patterns of the SSC favouring the formation of a tombolo, the dominance of wind-driven currents

  19. Sedimentary history and mass flow structures of Chryse and Acidalia Planitiae, Mars (United States)

    Tanaka, K.L.


    Geologic mapping and crater counting in Chryse and Acidalia Planitiae (GAP) reveal five major sedimentary deposits of Hesperian to Early Amazonian age, including (1) a mass flow deposited during the Early Hesperian near Deuteronilus Mensae (northeast of the map region) that may have resulted from the carving of Kasei Valles, >3000 km southwest of the exposed part of the deposit; (2) knobby plains material consisting of channel (likely; from Simud and Tiu Valles and possibly Ares and Shalbatana Valles) and mass-wasting deposits in central and eastern CAP; (3) material largely from Maja and Ares Valles emplaced in at least western and southern CAP (outcrops in southern Chryse Planitia developed thermokarst); (4) a thin mass flow covering much of southern Chryse Planitia that emanated from Simud and Tiu Valles; and (5) a thick, extensive (perhaps >3500 km across) mass flow deposit in central and northern CAP derived from accumulation and backflow of the preceding thin mass flow or perhaps melting of polar deposits. Other possible deposits may not be recognizable owing to burial by younger materials or a lack of morphologic signature. Various associated landforms appear to be consistent with the mass flow interpretations, including lobate and linear scarps along deposit edges, fractures related to desiccation of thick sediments, troughs, and ridges near the edges of the deposit indicative of secondary mass movement and deformation, pitted domes and fissure-fed flows possibly formed by sedimentary (mud) eruptions, and longitudinal channel grooves perhaps formed by roller vortices. No convincing evidence for paleoshorelines or stagnant ice sheets is found in CAP. These findings suggest that mass flow and hyperconcentrated flooding may have been the predominant processes of outflow-channel dissection in CAP. Elsewhere in the northern plains, similar landforms are prevalent. The mass flow interpretation does not require either multiple episodes of extraordinarily high

  20. Hydraulic jumps within pyroclastic density currents and their sedimentary record (United States)

    Douillet, G.; Mueller, S.; Kueppers, U.; Dingwell, D. B.


    This contribution presents a complete and comprehensive formulation of the hydraulic jump phenomenon and reviews sedimentary structures that may be associated with them. Beginning from the general fluid phenomenon, we then focus on examples from pyroclastic density currents in order to infer dynamic parameters on the parent flows. A hydraulic jump is a fluid dynamics phenomenon that corresponds to the sudden increase of the thickness of a flow accompanied by a decrease of its velocity and/or density. A hydraulic jump is the expression of the transition of the flow from two different flow regimes: supercritical to subcritical. This entrains a change in the energy balance between kinetic energy and gravity potential energy. Recently, the terms of 'pneumatic jumps' have been used for similar phenomenon driven within a gas phase, and granular jumps for dense granular flows. It is thought that such strong changes in the flow conditions may leave characteristic structures in the sedimentary record. Indeed, the main variables influencing the sedimentation rate are the flow velocity, particle concentration and turbulence level, all of them strongly affected by a hydraulic jump. Structures deposited by hydraulic/pneumatic jumps have been called cyclic steps and chute and pool structures. Chute and pools represent the record of a single supercritical to subcritical transition, whereas cyclic steps are produced by stable trains of hydraulic jumps and subsequent re-accelerations. Pyroclastic density currents (PDCs) are gas and pyroclasts flows. As such, they can be subjected to granular and pneumatic jumps and their deposit have often been interpreted as containing records of jumps. Steep sided truncations covered by lensoidal layers have been interpreted as the record of internal jumps within density stratified flows. Fines-depleted breccias at breaks in slope are thought to result from the enhanced turbulence at a jump of the entire flow. Sudden increases in thickness of

  1. Magnetic fabrics in tectonically inverted sedimentary basins: a review (United States)

    García-Lasanta, Cristina; Román-Berdiel, Teresa; Casas-Sainz, Antonio; Oliva-Urcia, Belén; Soto, Ruth; Izquierdo-Llavall, Esther


    Magnetic fabric studies in sedimentary rocks were firstly focused on strongly deformed tectonic contexts, such as fold-and-thrust belts. As measurement techniques were improved by the introduction of high-resolution equipments (e.g. KLY3-S and more recent Kappabridge susceptometers from AGICO Inc., Czech Republic), more complex tectonic contexts could be subjected to anisotropy of magnetic susceptibility (AMS) analyses in order to describe the relationship between tectonic conditions and the orientation and shape of the resultant magnetic ellipsoids. One of the most common complex tectonic frames involving deformed sedimentary rocks are inverted extensional basins. In the last decade, multiple AMS studies revealed that the magnetic fabric associated with the extensional stage (i.e. a primary magnetic fabric) can be preserved despite the occurrence of subsequent deformational processes. In these cases, magnetic fabrics may provide valuable information about the geometry and kinematics of the extensional episode (i.e. magnetic ellipsoids with their minimum susceptibility axis oriented perpendicular to the deposit plane and magnetic lineation oriented parallel to the extension direction). On the other hand, several of these studies have also determined how the subsequent compressional stage can modify the primary extensional fabric in some cases, particularly in areas subjected to more intense deformation (with development of compression-related cleavage). In this contribution we present a compilation of AMS studies developed in sedimentary basins that underwent different degree of tectonic inversion during their history, in order to describe the relationship of this degree of deformation and the degree of imprint that tectonic conditions have in the previous magnetic ellipsoid (primary extension-related geometry). The inverted basins included in this synthesis are located in the Iberian Peninsula and show: i) weak deformation (W Castilian Branch and Maestrazgo basin

  2. Early Archaean crustal collapse structures and sedimentary basin dynamics (United States)

    Nijman, W.; de Vries, S. T.


    Observations in the Lower Archaean (>3.3 Ga) of the Pilbara and Kaapvaal Cratons point to a direct genetic relationship between the thickness and facies distribution of volcano-sedimentary basin fills and non-linear patterns of extensional faults in early Earth. The basin fills consist of mafic volcanic products, largely pillow basalts, with distinct phases of intermediate to felsic volcanism and concentration of silica, either primary or secondary, in sediments deposited near base-level. The extensional structures are listric growth-faults, arranged in superposed arrays, that migrated upwards with the growth of the Early Archaean stratigraphical column. The faults linked intermittently occurring shallow-level felsic intrusions via porphyry pipes, veins and hydrothermal circulations with the surficial sedimentary basin fill of cherty sediments, concurrent mineralisation and alteration products. The non-linear pattern of the fault systems is recorded by their restored facing directions over large areas and corresponds best with over 100 km-wide (semi)circular crustal collapse structures. Crustal collapse, and therefore basin formation, did not represent a reaction to compression and crustal thickening. It also had no relationship with the present-day distribution of granitoid domes and greenstone belts. Collapse followed crustal uplift recorded by shallowing of the basin fill from a general subaqueous level of deposition of pillow basalts towards zero water level for the sediments and low-relief emersion. Maxima of extension coincide with the appearance of intermediate or felsic volcanic rocks in the overall mafic environment. The geodynamical setting is most appropriately explained by crustal delamination and related plume activity. Although individual features may be compared to Phanerozoic and Recent geological phenomena, like calderas, for the collapse structures as a whole such younger counterparts cannot be found. Rather they have their equivalents in collapse

  3. Hydrogeologic framework of fractured sedimentary rock, Newark Basin, New Jersey (United States)

    Lacombe, Pierre J.; Burton, William C.


    The hydrogeologic framework of fractured sedimentary bedrock at the former Naval Air Warfare Center (NAWC), Trenton, New Jersey, a trichloroethylene (TCE)-contaminated site in the Newark Basin, is developed using an understanding of the geologic history of the strata, gamma-ray logs, and rock cores. NAWC is the newest field research site established as part of the U.S. Geological Survey Toxic Substances Hydrology Program, Department of Defense (DoD) Strategic Environmental Research and Development Program, and DoD Environmental Security Technology Certification Program to investigate contaminant remediation in fractured rock. Sedimentary bedrock at the NAWC research site comprises the Skunk Hollow, Byram, and Ewing Creek Members of the Lockatong Formation and Raven Rock Member of the Stockton Formation. Muds of the Lockatong Formation that were deposited in Van Houten cycles during the Triassic have lithified to form the bedrock that is typical of much of the Newark Basin. Four lithotypes formed from the sediments include black, carbon-rich laminated mudstone, dark-gray laminated mudstone, light-gray massive mudstone, and red massive mudstone. Diagenesis, tectonic compression, off-loading, and weathering have altered the rocks to give some strata greater hydraulic conductivity than other strata. Each stratum in the Lockatong Formation is 0.3 to 8 m thick, strikes N65 degrees E, and dips 25 degrees to 70 degrees NW. The black, carbon-rich laminated mudstone tends to fracture easily, has a relatively high hydraulic conductivity and is associated with high natural gamma-ray count rates. The dark-gray laminated mudstone is less fractured and has a lower hydraulic conductivity than the black carbon-rich laminated mudstone. The light-gray and the red massive mudstones are highly indurated and tend to have the least fractures and a low hydraulic conductivity. The differences in gamma-ray count rates for different mudstones allow gamma-ray logs to be used to correlate and

  4. Human exposure to soil contaminants in subarctic Ontario, Canada

    Directory of Open Access Journals (Sweden)

    Ellen Stephanie Reyes


    Full Text Available Background: Chemical contaminants in the Canadian subarctic present a health risk with exposures primarily occurring via the food consumption. Objective: Characterization of soil contaminants is needed in northern Canada due to increased gardening and agricultural food security initiatives and the presence of known point sources of pollution. Design: A field study was conducted in the western James Bay Region of Ontario, Canada, to examine the concentrations of polychlorinated biphenyls, dichlorodiphenyltrichloroethane and its metabolites (ΣDDT, other organochlorines, and metals/metalloids in potentially contaminated agriculture sites. Methods: Exposure pathways were assessed by comparing the estimated daily intake to acceptable daily intake values. Ninety soil samples were collected at random (grid sampling from 3 plots (A, B, and C in Fort Albany (on the mainland, subarctic Ontario, Canada. The contaminated-soil samples were analysed by gas chromatography with an electron capture detector or inductively coupled plasma mass spectrometer. Results: The range of ΣDDT in 90 soil samples was below the limit of detection to 4.19 mg/kg. From the 3 soil plots analysed, Plot A had the highest ΣDDT mean concentration of 1.12 mg/kg, followed by Plot B and Plot C which had 0.09 and 0.01 mg/kg, respectively. Concentrations of other organic contaminants and metals in the soil samples were below the limit of detection or found in low concentrations in all plots and did not present a human health risk. Conclusions: Exposure analyses showed that the human risk was below regulatory thresholds. However, the ΣDDT concentration in Plot A exceeded soil guidelines set out by the Canadian Council of Ministers of the Environment of 0.7 mg/kg, and thus the land should not be used for agricultural or recreational purposes. Both Plots B and C were below threshold limits, and this land can be used for agricultural purposes.

  5. Paint removal activities in Canada (United States)

    Foster, Terry


    Paint removal activities currently under way in Canada include: research and development of laser paint stripping; development and commercialization of a new blasting medium based on wheat starch; commercialization of a new blasting medium and process using crystalline ice blasting for paint removal and surface cleaning; and the development of automated and robotic systems for paint stripping applications. A specification for plastic media blasting (PMB) of aircraft and aircraft components is currently being drafted by NDHQ for use by the Canadian Armed Forces (CAF) and contractors involved in coating removal for the CAF. Defense Research Establishment Pacific (DREP) is studying the effects of various blast media on coating removal rates, and minimizing the possibility of damage to substrates other than aluminum such as graphite epoxy composite and Kevlar. The effects of plastic media blasting on liquid penetrant detection of fatigue cracks is also under investigation.

  6. Forest insect pests in Canada

    Energy Technology Data Exchange (ETDEWEB)



    The papers presented in this book cover the range of forest insect pest management activities in Canada. The first section contains papers on the current status of insect pests by region, including data on insect populations and extent of defoliation caused by the insect. The next section covers pest management technology, including the use of insecticides, insect viruses, fungal pathogens, growth regulators, antifeedants, pheromones, natural predators, and aerial spraying. The third section contains papers on the application of technology and equipment for forest pest control, and includes papers on the impacts of insecticides on the forest environment. The fourth section describes operational control programs by province. The final paper presents future strategies for the management of forest pests. An author index is included.

  7. Cinéma / Canada


    Berthomé, Jean-Pierre; Coulombe, Michel; Dvorak, Marta; Garel, Sylvain; Noguez, Dominique; Suchet, Simone; Vimenet, Pascal


    Longtemps connue en France par le biais de cinéastes québécois tels que Claude Jutra, Gilles Carle, ou Pierre Perrault, l'industrie cinématographique du Canada a dû se développer dans l'ombre d'Hollywood. Elle s'est forgée une réputation internationale d'excellence dans les domaines qui ne concurrençaient pas les studios américains : le documentaire, le court-métrage, et les films d'animation. Nous sommes en présence d'un cinéma fortement subventionné (et même d'un cinéma d'État) qui repose s...

  8. Canada's population: growth and dualism. (United States)

    Beaujot, R P


    In Canada the current 1.3% population growth rate is causing some concern. Those concerned argue that such a rate of growth in combination with high levels of consumption could jeopardize the country's resource base and its comfortable style of living. Many Canadians are questioning high levels of immigration, for now that the fertility level is below replacement level, net immigration contributes substantially to population growth (over 1/3 in 1976). The growing proportion of non-Europeans among recent immigrants is causing resentment, and, in a tight job market, immigrants are regarded as threats to the World War 2 baby boom cohort who are now at working ages. The baby boom generation also puts stress on housing and health services, and it will increase the need for pension checks as it ages. Although French fertility is no longer high and immigration is no longer dominated by the British, the French group's 200-year struggle to preserve its identity continues on in the current effort of the Quebec government to enforce the use of French language by law within that province. Geography and climate dictate another demographic fact that divides the country and pervades its history. In addition to intense regionalism, uneven population distribution is responsible for 2 other concerns: the rapid growth of several already large cities and depopulation of many small communities. Focus in this discussion is on Canada's population growth in the past and as projected for the future, historical and current fertility, mortality and immigration trends, the search for a new immigration policy, the impact of the baby boom generation on the population's age structure and the problems this creates, and recent shifts in population distribution and in the country's ethnic and linguistic makeup. The population policy proposals evolved thus far involve to a great extent the use of immigration as a lever for achieving given population objectives.

  9. Sedimentary features of the Blackhawk formation (Cretaceous) at Sunnyside, Carbon County, Utah (United States)

    Maberry, John O.


    The Blackhawk Formation at Sunnyside, Utah, was deposited along the western margin of the Western Interior Cretaceous sea during southeastward withdrawal of the sea. Sand was the dominant type of land-derived sediment deposited in the Sunnyside district during the regressive phases. Sand bodies prograded seaward in response to changing sediment supply from a source west of Sunnyside. Where conditions were favorable for the accumulation of vegetable material, peat deposits formed and were later changed to bituminous Coal by diagenesis. Studies of the coal bed show that the coals were formed from accumulation of small, low-growing plants and plant debris that was transported into the area of accumulation. Remains of large plants in the coals are rare. Trace fossils, which are tracks, trails and burrows formed by organisms and preserved in the rock, are extremely abundant in the Blackhawk rocks. These biogenic sedimentary structures are common in Cretaceous deposits throughout the western United States. Trace fossil distribution in the rocks is controlled by the depositional environment preferred by their creators. A study of the trace fossils of a. locality allows a more precise determination of the conditions during deposition of the sediments. Water depth, bottom conditions, salinity, current velocity and amount of suspended nutrients in the water are some of the environmental factors that may be reconstructed by studying trace fossils. The Blackhawk Formation at Sunnyside comprises the members, the Kenilworth Member and the Sunnyside Member. Field studies show that the formation may be further subdivided in the Sunnyside district., according to the precepts of units of mappable thickness and similar lithologic characteristics. The Blackhawk pinches out eastward and north. ward into the Mancos Shale, and names for submembers become meaningless. Names are of value in the region of interest, however, because of the prominence of the named units. Coal mining is the

  10. A Bibliometric Analysis of Digestive Health Research in Canada

    Directory of Open Access Journals (Sweden)

    Désirée Tuitt


    Full Text Available Measurement of the impact and influence of medical/scientific journals, and of individual researchers has become more widely practiced in recent decades. This is driven, in part, by the increased availability of data regarding citations of research articles, and by increased competition for research funding. Digestive disease research has been identified as a particularly strong discipline in Canada. The authors collected quantitative data on the impact and influence of Canadian digestive health research. The present study involved an analysis of the research impact (Hirsch factor and research influence (Influence factor of 106 digestive health researchers in Canada. Rankings of the top 25 researchers on the basis of the two metrics were dominated by the larger research groups at the University of Toronto (Toronto, Ontario, McMaster University (Hamilton, Ontario, and the Universities of Calgary (Calgary, Alberta and Alberta (Edmonton, Alberta, but with representation by other research groups at the Universities of Manitoba (Winnipeg, Manitoba, Western Ontario (London, Ontario and McGill University (Montreal, Quebec. Female and male researchers had similar scores for the two metrics, as did basic scientists versus clinical investigators. Strategic recruitment, particularly of established investigators, can have a major impact on the ranking of research groups. Comparing these metrics over different time frames can provide insights into the vulnerabilities and strengths of research groups.

  11. Paleomagnetic studies on sedimentary Jurassic rocks from southern Bulgaria (United States)

    Kruczyk, J.; Kaḑziałko-Hofmokl, M.; Nozharov, P.; Petkov, N.; Nachev, I.

    Paleomagnetic investigations were performed on Jurassic sediments sampled in the mobile area of Bulgaria comprising Srednogorie, Kreiste and Stranja. The main carriers of magnetic properties of rocks studied are pigmentary haematite and goethite of post-sedimentary origin. The characteristic component of natural remanence (CARM), isolated by means of analysis of demagnetization procedure is secondary, and was acquired after the main tectonic event that took place in this area during the Upper Cretaceous. The CARM directions before tectonic correction are close to the results for Upper Cretaceous magmatic rocks from Srednogorie. The mean CARM direction and the corresponding polar position obtained for the whole region studied are compared with reference data for the Eurasian Platform. The difference between the reference and our data implies anticlockwise rotation of southern Bulgaria relative to Eurasia by ˜ 10-20° and a northward tilt of the region under study by ˜ 10-15° after acquisition of CARM.

  12. Sources of sedimentary humic substances: vascular plant debris (United States)

    Ertel, John R.; Hedges, John I.


    A modern Washington continental shelf sediment was fractionated densimetrically using either an organic solvent, CBrCl 3, or aqueous ZnCl 2. The resulting low density materials (extraction of fresh and naturally degraded vascular plant materials reveals that significant levels of humic and fulvic acids are obtained using classical extraction techniques. Approximately 1-2% of the carbon from fresh woods and 10-25% from leaves and bark were isolated as humic acids and 2-4 times those levels as fulvic acids. A highly degraded hardwood yielded up to 44% of its carbon as humic and fulvic acids. The humic acids from fresh plants are generally enriched in lignin components relative to carbohydrates and recognizable biochemicals account for up to 50% of the total carbon. Humic and fulvic acids extracted directly from sedimentary plant debris could be responsible for a major fraction of the biochemical component of humic substances.

  13. Multilayered aquifer modeling in the coastal sedimentary basin of Togo (United States)

    Gnazou, M. D. T.; Sabi, B. E.; Lavalade, J. L.; Schwartz, J.; Akakpo, W.; Tozo, A.


    This work is a follow up to the hydrogeological synthesis done in 2012 on the coastal sedimentary basin of Togo. That synthesis notably emphasized the lack of piezometric monitoring in the last thirty years. This has kept us from learning about the dynamics and evolution of the resource in the context of rapidly increasing demand. We are therefore presenting a model for understanding flows, and its main objectives are to provide an initial management tool that should evolve with time as new data (piezometric monitoring, pumping tests, etc.) become available, and to determine what new information can be obtained that will help policy makers to manage the resource better. The results of steady state flow calibration have shown that the aquifer of the Continental Terminal overexploited in the West, can still be exploited in the East of the basin, the Maastrichtian on the whole basin. On the other hand, exploitation of Paleocene aquifers should be done with care.

  14. Test of hyperelasticity in highly nonlinear solids: sedimentary rocks. (United States)

    D'Angelo, R M; Winkler, K W; Plona, T J; Landsberger, B J; Johnson, D L


    We report measurements of three-wave mixing amplitudes on systems whose third order elastic constants have also been measured by means of the elastoacoustic effect. Because attenuation and diffraction are an important aspect of our measurement technique we analyze our results using a modified Khoklhov-Zabolotskaya-Kuznetsov equation in the frequency domain. We find that the value of beta so deduced for polymethyl methacrylate agrees quite well with that predicted from the stress dependent sound speed measurements, establishing that polymethyl methacrylate may be considered as a hyperelastic solid. The beta values of sedimentary rocks, though they are typically 2 orders of magnitude larger than, e.g., polymethyl methacrylates, are still a factor 3-10 less than those predicted from the elastoacoustic effect.

  15. Sediment Flux from Stratigraphy: Insights from 300 Ma Sedimentary Archives (United States)

    Romans, B.; Mason, C. C.; Eriksson, K. A.


    Tectonic or climate signals that originate in net-erosional catchments are transmitted down-system as sediment. The accumulation of that sediment in net-depositional regions and preservation as stratigraphy can be accessed and used to reconstruct signal generation and propagation. Studies of modern to millennial rates in deep-time sedimentary archives do not yet exist. Here, we use the extraordinary tidal rhythmite deposits of the Pride Shale in the Appalachian Basin as a high-resolution chronometer to constrain the duration of basin filling. We then use the scale of fluvial channel bodies in the underlying and overlying units combined with climate-specific empirical relationships derived from modern systems to estimate the size of the paleo-catchment. The resultant estimates of sediment yield allow calculation of denudation rates for a system in which the catchment has long-since eroded.

  16. Research into surface wave phenomena in sedimentary basins (United States)

    Wojcik, G. L.; Isenberg, J.; Ma, F.; Richardson, E.


    This study is a continuation of an engineering seismology research effort prompted by the sensitivity of guidance sets in Minuteman Wing V to distant earthquakes. An earlier report considers the probable cause of anomalous patterns of seismic alarms triggered by two North American earthquakes. This report extends the previous study by examining the propagation of surface waves from the 1975 Pocatello Valley, Idaho earthquake sequence across Wyoming to Wing V. In addition, the more general question of surface wave phenomena in sedimentary basins is addressed, particularly the effect of laterally inhomogeneous (dipping) basin-bedrock interfaces. Findings indicate that fundamental and first overtone surface waves are significantly modified by the travel path. In contrast, higher modes are relatively unchanged by the travel path, and affect Wing V in much the same way as body waves considered in the previous study.

  17. Recent trends and variability in river discharge across northern Canada (United States)

    Déry, Stephen J.; Stadnyk, Tricia A.; MacDonald, Matthew K.; Gauli-Sharma, Bunu


    This study presents an analysis of the observed inter-annual variability and inter-decadal trends in river discharge across northern Canada for 1964-2013. The 42 rivers chosen for this study span a combined gauged area of 5.26 × 106 km2 and are selected based on data availability and quality, gauged area and record length. Inter-annual variability in river discharge is greatest for the eastern Arctic Ocean (coefficient of variation, CV = 16 %) due to the Caniapiscau River diversion into the La Grande Rivière system for enhanced hydropower production. Variability is lowest for the study area as a whole (CV = 7 %). Based on the Mann-Kendall test (MKT), no significant (p > 0.05) trend in annual discharge from 1964 to 2013 is observed in the Bering Sea, western Arctic Ocean, western Hudson and James Bay, and Labrador Sea; for northern Canada as a whole, however, a statistically significant (p < 0.05) decline of 102.8 km3 25 yr-1 in discharge occurs over the first half of the study period followed by a statistically significant (p < 0.05) increase of 208.8 km3 25 yr-1 in the latter half. Increasing (decreasing) trends in river discharge to the eastern Hudson and James Bay (eastern Arctic Ocean) are largely explained by the Caniapiscau diversion to the La Grande Rivière system. Strong regional variations in seasonal trends of river discharge are observed, with overall winter (summer) flows increasing (decreasing, with the exception of the most recent decade) partly due to flow regulation and storage for enhanced hydropower production along the Hudson and James Bay, the eastern Arctic Ocean and Labrador Sea. Flow regulation also suppresses the natural variability of river discharge, particularly during cold seasons.

  18. PUMa - modelling the groundwater flow in Baltic Sedimentary Basin (United States)

    Kalvane, G.; Marnica, A.; Bethers, U.


    In 2009-2012 at University of Latvia and Latvia University of Agriculture project "Establishment of interdisciplinary scientist group and modelling system for groundwater research" is implemented financed by the European Social Fund. The aim of the project is to develop groundwater research in Latvia by establishing interdisciplinary research group and modelling system covering groundwater flow in the Baltic Sedimentary Basin. Researchers from fields like geology, chemistry, mathematical modelling, physics and environmental engineering are involved in the project. The modelling system is used as a platform for addressing scientific problems such as: (1) large-scale groundwater flow in Baltic Sedimentary Basin and impact of human activities on it; (2) the evolution of groundwater flow since the last glaciation and subglacial groundwater recharge; (3) the effects of climate changes on shallow groundwater and interaction of hydrographical network and groundwater; (4) new programming approaches for groundwater modelling. Within the frame of the project most accessible geological information such as description of geological wells, geological maps and results of seismic profiling in Latvia as well as Estonia and Lithuania are collected and integrated into modelling system. For example data form more then 40 thousands wells are directly used to automatically generate the geological structure of the model. Additionally a groundwater sampling campaign is undertaken. Contents of CFC, stabile isotopes of O and H and radiocarbon are the most significant parameters of groundwater that are established in unprecedented scale for Latvia. The most important modelling results will be published in web as a data set. Project number: 2009/0212/1DP/ Project web-site:

  19. Modeling of the nonlinear resonant response in sedimentary rocks

    Energy Technology Data Exchange (ETDEWEB)

    Ten Cate, James A [Los Alamos National Laboratory; Shankland, Thomas J [Los Alamos National Laboratory; Vakhnenko, Vyacheslav O [NON LANL; Vakhnenko, Oleksiy [NON LANL


    We suggest a model for describing a wide class of nonlinear and hysteretic effects in sedimentary rocks at longitudinal bar resonance. In particular, we explain: hysteretic behaviour of a resonance curve on both its upward and downward slopes; linear softening of resonant frequency with increase of driving level; gradual (almost logarithmic) recovery of resonant frequency after large dynamical strains; and temporal relaxation of response amplitude at fixed frequency. Starting with a suggested model, we predict the dynamical realization of end-point memory in resonating bar experiments with a cyclic frequency protocol. These theoretical findings were confirmed experimentally at Los Alamos National Laboratory. Sedimentary rocks, particularly sandstones, are distinguished by their grain structure in which each grain is much harder than the intergrain cementation material. The peculiarities of grain and pore structures give rise to a variety of remarkable nonlinear mechanical properties demonstrated by rocks, both at quasistatic and alternating dynamic loading. Thus, the hysteresis earlier established for the stress-strain relation in samples subjected to quasistatic loading-unloading cycles has also been discovered for the relation between acceleration amplitude and driving frequency in bar-shaped samples subjected to an alternating external drive that is frequency-swept through resonance. At strong drive levels there is an unusual, almost linear decrease of resonant frequency with strain amplitude, and there are long-term relaxation phenomena such as nearly logarithmic recovery (increase) of resonant frequency after the large conditioning drive has been removed. In this report we present a short sketch of a model for explaining numerous experimental observations seen in forced longitudinal oscillations of sandstone bars. According to our theory a broad set of experimental data can be understood as various aspects of the same internally consistent pattern. Furthermore

  20. Predicting the transport properties of sedimentary rocks from microstructure

    Energy Technology Data Exchange (ETDEWEB)

    Schlueter, Erika M. [Univ. of California, Berkeley, CA (United States)


    Understanding transport properties of sedimentary rocks, including permeability, relative permeability, and electrical conductivity, is of great importance for petroleum engineering, waste isolation, environmental restoration, and other applications. These transport properties axe controlled to a great extent by the pore structure. How pore geometry, topology, and the physics and chemistry of mineral-fluid and fluid-fluid interactions affect the flow of fluids through consolidated/partially consolidated porous media are investigated analytically and experimentally. Hydraulic and electrical conductivity of sedimentary rocks are predicted from the microscopic geometry of the pore space. Cross-sectional areas and perimeters of individual pores are estimated from two-dimensional scanning electron microscope (SEM) photomicrographs of rock sections. Results, using Berea, Boise, Massilon, and Saint-Gilles sandstones show close agreement between the predicted and measured permeabilities. Good to fair agreement is found in the case of electrical conductivity. In particular, good agreement is found for a poorly cemented rock such as Saint-Gilles sandstone, whereas the agreement is not very good for well-cemented rocks. The possible reasons for this are investigated. The surface conductance contribution of clay minerals to the overall electrical conductivity is assessed. The effect of partial hydrocarbon saturation on overall rock conductivity, and on the Archie saturation exponent, is discussed. The region of validity of the well-known Kozeny-Carman permeability formulae for consolidated porous media and their relationship to the microscopic spatial variations of channel dimensions are established. It is found that the permeabilities predicted by the Kozeny-Carman equations are valid within a factor of three of the observed values methods.

  1. Tectonic and sedimentary evolution of the Luna field area, Italy

    Energy Technology Data Exchange (ETDEWEB)

    Roveri, M. (AGIP S.A., Milan (Italy))


    The Luna gas field is located near Crotone (Calabria region, southern Italy) in a shallow-water/onshore area. It was discovered and put into production during the early 1970s. Up to now it has produced 19 {times} 10{sup 9} sm{sup 3} of gas; its productivity (50 {times} 10{sup 6} sm{sup 3}/y) has remained virtually unaltered since the beginning. The field is located on the axial culmination of a thrust-related anticline of the Apennine postcollisional thrust belt; it can be roughly subdivided into two areas characterized by different stratigraphic contexts. In the northern and central parts of the field is a structural trap. Reservoir rocks are Serravallian to Tortonian deep marine resedimented conglomerates and sandstones. These deposits represent part of the infill of a middle-upper Miocene foredeep. Reservoir rocks are now thrusted, eroded, and unconformably overlain by lower Pliocene shales, which are the most important seal in this part of the field. In the southern part of the field is a combination trap. Reservoir rocks are upper Tortonian shallow-water sandstones. They lap onto a Tortonian unconformity related to a tectonic phase which split the previous foredeep into minor piggyback basins. The upper Tortonian sandstones are overlain and sealed by Messinian shales and evaporites. Tectonosedimentary evolution of the area and, consequently, areal distribution and geometry of sedimentary bodies - both potential reservoirs and seals - have been reconstructed using a sequence stratigraphy approach. The sedimentary record has been informally subdivided into five main depositional sequences bounded by unconformities or their correlative conformities; classic facies analysis and petrophysical, seismic, and biostratigraphic data have been utilized to define the internal characteristics of each sequence.

  2. Estimation of sedimentary proxy records together with associated uncertainty

    Directory of Open Access Journals (Sweden)

    B. Goswami


    Full Text Available Sedimentary proxy records constitute a significant portion of the recorded evidence that allow us to investigate paleoclimatic conditions and variability. However, uncertainties in the dating of proxy archives limit our ability to fix the timing of past events and interpret proxy record inter-comparisons. While there are various age-modeling approaches to improve the estimation of the age-depth relations of archives, relatively less focus has been given to the propagation of the age (and radiocarbon calibration uncertainties into the final proxy record. We present a generic Bayesian framework to estimate proxy records along with their associated uncertainty starting with the radiometric age-depth and proxy-depth measurements, and a radiometric calibration curve if required. We provide analytical expressions for the posterior proxy probability distributions at any given calendar age, from which the expected proxy values and their uncertainty can be estimated. We illustrate our method using two synthetic datasets and then use it to construct the proxy records for groundwater inflow and surface erosion from Lonar lake in central India. Our analysis reveals interrelations between the uncertainty of the proxy record over time and the variance of proxy along the depth of the archive. For the Lonar lake proxies, we show that, rather than the age uncertainties, it is the proxy variance combined with calibration uncertainty that accounts for most of the final uncertainty. We represent the proxy records as probability distributions on a precise, error-free time scale that makes further time series analyses and inter-comparison of proxies relatively simpler and clearer. Our approach provides a coherent understanding of age uncertainties within sedimentary proxy records that involve radiometric dating. It can be potentially used within existing age modeling structures to bring forth a reliable and consistent framework for proxy record estimation.

  3. A tale of two cedars – International symposium on western redcedar and yellow-cedar (United States)

    Constance Harrington


    From May 24-28, 2010, an international symposium on western redcedar (Thuja plicata) and yellowcedar (Callitropsis nootkatensis [syn., Chamaecyparis nootkatensis]) was held at the University of Victoria on Vancouver Island in British Columbia, Canada. The symposium was entitled “A Tale of Two Cedars” and...

  4. Whales, Dolphins, and Porpoises of the Western North Atlantic: A Guide to Their Identification. (United States)

    Leatherwood, Stephen; And Others

    This field guide is designed to permit observers to identify the cetaceans (whales, dolphins, and porpoises) they see in western North Atlantic, including the Caribbean Sea, the Gulf of Mexico, and the coastal waters of the United States and Canada. The animals described are not grouped by scientific relationships but by similarities in appearance…

  5. Colliding Rights in the Schools: Trinity Western University v. The British Columbia College of Teachers. (United States)

    Van Brummelen, Harro; Sawatsky, Kevin


    Discusses British Columbia College of Teachers' (BCCT) denial of Trinity Western University's (TWU) teacher education programs and teacher certification due to TWU's prohibition of homosexuality. Reports that TWU filed suit, and the Supreme Court of Canada determined that BCCT's action interfered with TWU's right to religious freedom. (Contains 32…

  6. Western Retrospections and Outlook

    Institute of Scientific and Technical Information of China (English)


    This year marks the 10-year anniversary of the strategy on development of China’s western region. With a land area of 6.85 million square km, accounting for 71.4 percent of the country’s total, the western region has been an indispensable part in achieving China’s overall prosperity and

  7. The volcanic-sedimentary sequence of the Lousal deposit, Iberian Pyrite Belt (Portugal) (United States)

    Rosa, Carlos; Rosa, Diogo; Matos, Joao; Relvas, Jorge


    The Iberian Pyrite Belt (IPB) is a massive sulfide province that is located in the south of Portugal and Spain, and hosts more than 90 massive sulfide deposits that amount to more than 1850 million metric tonnes of sulfide ore (Tornos, 2006). The ore deposits size, vary from ~1Mt to >100Mt (e.g. Neves Corvo and Aljustrel in Portugal, and Rio Tinto and Tharsis in Spain). The ore deposits are hosted by a submarine sedimentary and volcanic, felsic dominated, succession that constitutes the Upper Devonian to Lower Carboniferous Volcanic and Sedimentary Complex (VSC). The VSC ranges in thickness from approximately 600 to 1300 m (Tornos 2006). The VSC overlies the Phyllite-Quartzite Group (PQ) (Upper Devonian, base unknown) and is overlain by the Baixo Alentejo Flysch Group (Lower to Upper Carboniferous). The Lousal massive sulfide deposit is located in the western part of the IPB and occurs mostly interbedded with black mudstone. The VSC sequence at Lousal mine consists of a mudstone and quartzite sequence (PQ Group) in the lower part of the succession, over which a thick sequence of rhyolitic lavas (>300 m) occurs. Above the rhyolitic lavas there is a thick sequence of black and grey mudstone that hosts the massive sulfide ore bodies, and a rhyolitic sill. The upper part of the VSC sequence consists of a thick mudstone interval that hosts two thick basaltic units, locally with pillows. The rhyolites have small coherent cores, locally with flow bands, that grade to surrounding massive clastic intervals, with large lateral extent. The clasts show jigsaw-fit arrangement in many places and have planar or curviplanar margins and locally are perlitic at the margin. The top contact of these units is in most locations not exposed, which makes difficult to interpret the mode of emplacement. However, the thick clastic intervals, above described, are in accordance with quenching of volcanic glass with abundant water and therefore indicate that quenching of the rhyolites was the

  8. Operational expert system applications in Canada

    CERN Document Server

    Suen, Ching Y


    This book is part of a new series on operational expert systems worldwide. Expert systems are now widely used in different parts of the world for various applications. The past four years have witnessed a steady growth in the development and deployment of expert systems in Canada. Research in this field has also gained considerable momentum during the past few years. However, the field of expert systems is still young in Canada. This book contains 13 chapters contributed by 31 experts from both universities and industries across Canada covering a wide range of applications related to electric

  9. Bailarinas Exoticas, Striptease e Inmigracion en Canada.

    Directory of Open Access Journals (Sweden)

    Gloria Patricia Diaz Barrero.


    Full Text Available This article is the product of exploratory field research conducted in Toronto, Canada. It consists of in-depth interviews of Latin American women from diverse countries who obtained temporary work visas as exotic dancers. The objective of the study is to determine the ways in which women are recruited in their countries of origin, transported to Canada and what happens to them upon arrival. The author proposes that the conditions inherent to migration, more than women's legal status, determines their emotional, economic and legal well-being. However, upon obtaining legal residency in Canada, abuse committed by employers and state agents is significantly reduced.

  10. Age and sedimentary record of inland eolian sediments in Lithuania, NE European Sand Belt

    DEFF Research Database (Denmark)

    Kalińska-Nartiša, Edyta; Thiel, Christine; Nartišs, Maris


    in any detail. The sedimentary structural-textural features are investigated and a chronology was derived using optically stimulated luminescence on both quartz and feldspar. The sedimentary structures and the rounding and surface characteristics of the quartz grains argue for a predominance of eolian...

  11. Well-log based prediction of temperature models in the exploration of sedimentary settings

    DEFF Research Database (Denmark)

    Fuchs, Sven; Förster, Andrea; Wonik, Thomas

    ) developed for matrix TC of sedimentary rocks. The equations resulted from a statistical analysis of an artificial set of mineral assemblages (consisting of 15 rock-forming minerals) typical for the different types of sedimentary rocks. The matrix TC was transformed into bulk TC by using a well-log derived...

  12. The sedimentary dynamics in natural and human-influenced delta channel belts

    NARCIS (Netherlands)

    Hobo, N.


    This study investigates the increased anthropogenic influence on the within-channel belt sedimentary dynamics in the Rhine delta. To make this investigation, the sedimentary dynamics within the life-cycle of a single channel belt were reconstructed for three key periods of increasing human impact, w

  13. Formation of Ocean Sedimentary Rocks as Active Planets and Life-Like Systems (United States)

    Miura, Y.


    Wet shocked rocks are discarded globally and enriched elements in ocean-sedimentary rocks, which is strong indicator of ocean water of other planets. Ocean-sedimentary rocks are strong indicator of water planets and possible exo-life on planet Mars.

  14. Stratigraphic Correlation of Middle Triassic Sequences among Different Paleogeographic Sedimentary Facies in South China

    Institute of Scientific and Technical Information of China (English)


    Affected by the Indosinian movement, the sediments in the main part of South China, Yangtzeplatform, started to transform from marine to continental during the Middle Triassic. In the meantime, a noticeable paleogeographic and sedimentary facies differentiation occurred in the marginal regions of the platforms and produced completely different lithologic and paleontologicsequences in various paleogeographic gradients and sedimentary facies areas, which brought about the difficulties for the stratigraphic correlation based on the traditional stratigraphies. This paper proposes to use some characteristic environmental events as the markers of the stratigraphic corre lation across various paleogeographic sedimentary facies, considering that some distinctive regionalenvironmental events should have affected at the same time on the entire basin or the connectedsedimentary regions and produced some closely related sedimentary records in the stratigraphic sequences though the affected intensity and recorded pattern might be different among the regions.The change of violent relative sea level (generally water depth) and the alteration of tectonic activity summarized from the dynamic mechanism of sedimentation are the best markers of environmental events for stratigraphic correlation. Based on the analysis and recognition of some significantenvironmental events at the typical stratigraphic sequences from various paleogeographic sedimentary facies and combined with the consideration of the variations in expressed form and strength fthe events among different paleogeographic gradients and sedimentary facies, the stratigraphic sequences from different sedimentary facies can be easily correlated directly. Furthermore, the evolutionary history of the whole sedimentary basin can be clearly established.

  15. Astronomical forcing and geochronological application of sedimentary cycles in the Mediterranean Pliocene-Pleistocene

    NARCIS (Netherlands)

    Hilgen, F.J.


    A new, astronomically calibrated time scale is presented for the Mediterranean Pliocene based on the correlation of sedimentary cycles to astronomical curves which describe the quasi-periodic variations in the Earth's orbit during the last 5.5 Ma. These sedimentary cycles are found in a continuous d

  16. Astronomical forcing and geochronological application of sedimentary cycles in the Mediterranean Pliocene-Pleistocene

    NARCIS (Netherlands)

    Hilgen, F.J.


    A new, astronomically calibrated time scale is presented for the Mediterranean Pliocene based on the correlation of sedimentary cycles to astronomical curves which describe the quasi-periodic variations in the Earth's orbit during the last 5.5 Ma. These sedimentary cycles are found in a

  17. Sedimentary process control on carbon isotope composition of sedimentary organic matter in an ancient shallow-water shelf succession (United States)

    Davies, S. J.; Leng, M. J.; Macquaker, J. H. S.; Hawkins, K.


    Source and delivery mechanisms of organic matter are rarely considered when interpreting changing δ13C through sedimentary successions even though isotope excursions are widely used to identify and correlate global perturbations in the carbon cycle. Combining detailed sedimentology and geochemistry we demonstrate how organic carbon abundance and δ13C values from sedimentary organic matter from Carboniferous-aged mudstones are influenced by the proportion of terrestrial versus water column-derived organic matter. Silt-bearing clay-rich shelf mudstones that were deposited by erosive density flows are characterized by 1.8-2.4% organic carbon and highδ13C values (averaging -22.9 ± 0.3‰, n = 12). Typically these mudstones contain significant volumes of terrestrial plant-derived material. In contrast, clay-rich lenticular mudstones, with a marine macrofauna, are the products of the transport of mud fragments, eroded from pre-existing water-rich shelfal muds, when shorelines were distant and biological productivity in the water column was high. Higher organic carbon (2.1-5.2%) and lowerδ13C values (averaging -24.3 ± 0.5‰, n = 11) characterize these mudstones and are interpreted to reflect a greater contribution by (isotopically more negative) amorphous organic matter derived from marine algae. Differences in δ13C between terrestrial and marine organic matter allow the changing proportions from different sources to be tracked through this succession. Combining δ13C values with zirconium (measured from whole rock), here used as a proxy for detrital silt input, provides a novel approach to distinguishing mudstone provenance and ultimately using δ13C to identify oil-prone organic matter in potential source rocks. These results have important implications for using bulk organic matter to identify and characterize global C-isotope excursions.

  18. Recent Developments for Satellite-Based Fire Monitoring in Canada (United States)

    Abuelgasim, A.; Fraser, R.


    Wildfires in Canadian forests are a major source of natural disturbance. These fires have a tremendous impact on the local environment, humans and wildlife, ecosystem function, weather, and climate. Approximately 9000 fires burn 3 million hectares per year in Canada (based on a 10-year average). While only 2 to 3 percent of these wildfires grow larger than 200 hectares in size, they account for almost 97 percent of the annual area burned. This provides an excellent opportunity to monitor active fires using a combination of low and high resolution sensors for the purpose of determining fire location and burned areas. Given the size of Canada, the use of remote sensing data is a cost-effective way to achieve a synoptic overview of large forest fire activity in near-real time. In 1998 the Canada Centre for Remote Sensing (CCRS) and the Canadian Forest Service (CFS) developed a system for Fire Monitoring, Mapping and Modelling (Fire M3; Fire M3 automatically identifies, monitors, and maps large forest fires on a daily basis using NOAA AVHRR data. These data are processed daily using the GEOCOMP-N satellite image processing system. This presentation will describe recent developments to Fire M3, included the addition of a set of algorithms tailored for NOAA-16 (N-16) data. The two fire detection algorithms are developed for N-16 day and night-time daily data collection. The algorithms exploit both the multi-spectral and thermal information from the AVHRR daily images. The set of N-16 day and night algorithms was used to generate daily active fire maps across North America for the 2001 fire season. Such a combined approach for fire detection leads to an improved detection rate, although day-time detection based on the new 1.6 um channel was much less effective (note - given the low detection rate with day time imagery, I don't think we can make the statement about capturing the diurnal cycle). Selected validation sites in western

  19. Canada Education Savings Program: Annual Statistical Review 2011 (United States)

    Human Resources and Skills Development Canada, 2011


    The Canada Education Savings Program has been an initiative of the Government of Canada since 1998. As part of the Department of Human Resources and Skills Development, the program administers the Canada Education Savings Grant and the Canada Learning Bond. These two initiatives help Canadian families save for a child's post-secondary education in…

  20. Canada Education Savings Program: Annual Statistical Review--2009 (United States)

    Human Resources and Skills Development Canada, 2009


    The Canada Education Savings Program is an initiative of the Government of Canada. As part of the Department of Human Resources and Skills Development, the program administers the Canada Education Savings Grant and the Canada Learning Bond. These two initiatives help Canadian families save for a child's post-secondary education in Registered…

  1. 9 CFR 93.418 - Cattle from Canada. (United States)


    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Cattle from Canada. 93.418 Section 93... CONVEYANCE AND SHIPPING CONTAINERS Ruminants Canada 8 § 93.418 Cattle from Canada. (a) Health certificates. Cattle intended for importation from Canada must be accompanied by a certificate issued in...

  2. 9 CFR 93.317 - Horses from Canada. (United States)


    ... period. (b) Horses of United States origin that are imported into Canada under an export health... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Horses from Canada. 93.317 Section 93... CONVEYANCE AND SHIPPING CONTAINERS Horses Canada 16 § 93.317 Horses from Canada. (a) Except as provided in...

  3. Cost Effectiveness of Infant Vaccination for Rotavirus in Canada

    Directory of Open Access Journals (Sweden)

    Doug Coyle


    Full Text Available INTRODUCTION: Rotavirus is the main cause of gastroenteritis in Canadian children younger than five years of age, resulting in significant morbidity and cost. The present study provides evidence on the cost effectiveness of two alternative rotavirus vaccinations (RotaTeq [Merck Frosst Canada Ltd, Canada] and Rotarix [GlaxoSmithKline, Canada] available in Canada.

  4. The mean residence time of river water in the Canada Basin

    Institute of Scientific and Technical Information of China (English)

    CHEN Min; XING Na; HUANG YiPu; QIU YuSheng


    Seawater was collected from the western Arctic Ocean for measurements of 18O, 226Ra and 228Ra. The fractions of river runoff and sea ice melt-water in water samples were estimated by using δ18O-S-PO* tracer system. The mean residence time of river water in the Canada Basin was calculated based on the relationship between 228Ra/226Ra)A.R. and the fractions of river runoff in the shelf and deep ocean. Our results showed that the river runoff fractions in the Canada Basin were significantly higher than those in the shelf regions, suggesting that the Canada Basin is a major storage region for Arctic river water. 228Ra activity concentrations in the Chukchi shelf and the Beaufort shelf ranged from 0.16 to 1.22 Bq/m3,lower than those reported for shelves in the low and middle latitudes, indicating the effect of sea ice melt-water. A good positive linear relationship was observed between 228Ra/226Ra)A.R. and the fraction of river runoff for shelf waters, while the 228Ra/226Ra)A.R in the Canada Basin was located below this regressive line. The low 228Ra/226Ra)A.R. in the Canada Basin was ascribed to 228Ra decay during shelf wa-ters transporting to the deep ocean. The residence time of 5.0-11.0 a was estimated for the river water in the Canada Basin, which determined the time response of surface freshening in the North Atlantic to the river runoff into the Arctic Ocean.

  5. Western Energy Corridor -- Energy Resource Report

    Energy Technology Data Exchange (ETDEWEB)

    Leslie Roberts; Michael Hagood


    The world is facing significant growth in energy demand over the next several decades. Strategic in meeting this demand are the world-class energy resources concentrated along the Rocky Mountains and northern plains in Canada and the U.S., informally referred to as the Western Energy Corridor (WEC). The fossil energy resources in this region are rivaled only in a very few places in the world, and the proven uranium reserves are among the world's largest. Also concentrated in this region are renewable resources contributing to wind power, hydro power, bioenergy, geothermal energy, and solar energy. Substantial existing and planned energy infrastructure, including refineries, pipelines, electrical transmission lines, and rail lines provide access to these resources.

  6. Energy policy and free trade in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Uslaner, E.M. (Maryland Univ., College Park, MD (USA))


    Canada and the USA signed a free trade agreement that went into effect on 1 January 1989. The USA saw the accord as having the potential to open markets in both countries for the mutual advantage of each. Americans have become more protectionist in recent years, but the object of such protectionism has been Japan rather than Canada. Canadians worried that the accord might lead to further economic and cultural domination by the USA. Many Canadians view their energy resources as a national birthright that can play a key role in fostering a sense of nationalism. Other Canadians consider energy resources to be provincial birthrights and worry that the federal government will interfere in free trade with other countries (especially the USA) to impose a feeling of nationalism on Canada. The debate over free trade thus mirrors that on energy in Canada. (author).

  7. 1982 Aleutian Canada goose nesting survey (United States)

    US Fish and Wildlife Service, Department of the Interior — Investigation of the endangered Aleutian Canada goose (Branta canadensis leucopareia) was conducted from 1974 to 1976, again in 1977 and in 1979 on Buldir. During...

  8. Immunizing Canada geese against avian cholera (United States)

    Price, J.I.


    A small flock of captive giant Canada geese were vaccinated with the experimental bac- terin in Nebraska to test its efficacy under field conditions. Only 2 of 157 vaccinates died from avian cholera during an annual spring die-off.

  9. Coaxial Connections: Art Education in Canada. (United States)

    Gray, James V.


    Several avenues of communication that bind art education in the United States and Canada are described. Developments of mutual understanding have tightened the art education relationship between the two countries. (RM)

  10. Cackling Canada goose nesting populations, Yukon Delta (United States)

    US Fish and Wildlife Service, Department of the Interior — Number of potential territories, number of cackling Canada Goose nests, and percent occupancy of available territories from CCG plots on the Yukon Delta National...

  11. Ammi Canada 2015 Annual Conference: Abstract Titles

    Directory of Open Access Journals (Sweden)


    Full Text Available Abstracts to be presented at the 2015 Annual Conference of the Association of Medical Microbiology and Infectious Disease Canada, April 16 to 18, Charlottetown, Prince Edward Island, alphabetized according to the surname of the first author.

  12. Mineral Operations of Latin America and Canada (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of records for over 900 mineral facilities in Latin America and Canada. The mineral facilities include mines, plants, smelters, or refineries...

  13. Options for sequestration of CO{sub 2} from major stationary point sources, British Columbia, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Danae A. Voormeij; George J. Simandl [University of Victoria, Victoria, BC (Canada)


    This study presents a conceptual overview of the major CO{sub 2} point sources for British Columbia (BC), Canada, and suggests potential geological sinks for the disposal of these emissions. In BC, stationary sources of CO{sub 2} include operations in aluminium and glass manufacturing; cement, chemical and smelting industries; oil and gas processing; coal operations; waste incinerators; pulp and paper mills; and, potentially, thermal power plants. In 2003, these point sources generated approximately 17 Mt of CO{sub 2} equivalent, about 26% of BC's total estimated GHG emissions. Major single stationary point sources or clusters of smaller stationary sources with combined emissions in excess of 500 kt/yr are located in the Vancouver area, Fort Nelson, Campbell River, Kitimat, Fort St. John, and Elkford.. BC is located on a tectonically active continental margin, which consists of a variety of sedimentary, igneous and metamorphic lithologies underlain by a crystalline basement. CO{sub 2} sequestration potential in sedimentary basins similar to that in Alberta is applicable only in northeastern BC. Alternate options need to be considered for the rest of BC, including injection of CO{sub 2} into deep coal seams, ocean disposal and mineral carbonation. Matching large stationary point sources to suitable sinks suggests that northeastern BC has potential for injection into deep saline aquifers, depleted gas reservoirs and coal beds. Vancouver Island and southeastern BC are also partly underlain by deep coal beds. Large tracts of ultramafic rocks bearing magnesium silicates indicate that the raw material necessary for the mineral sequestration process exists in sufficient amounts to sequester CO{sub 2} emissions from point sources in the Vancouver and Prince George regions. Offshore sedimentary basins are under a moratorium, which limits sequestration planning for stationary CO{sub 2}-emission sources located along the west coast. 26 refs., 4 figs., 1 tab.

  14. Western Conference Team Names

    Institute of Scientific and Technical Information of China (English)


    Memphis Grizzlies(孟菲斯灰熊) The Grizzlies were originally based in Van- couver,British Columbia,on Canada’s Pacific coast,where grizzly bears do live. Minnesota Timberwolves(明尼苏达森林狼) Minnesota,which is located on the border with Canada,contains large expanses of fores- ted wilderness where timberwolves make their home.

  15. Plating effluent management in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Paine, P. [Environment Canada, Hull, PQ (Canada)


    There are some 600 firms in Canada classified as metal finishers, employing about 8,000 people; 60 per cent of these firms are located in Ontario. Annual sales are in the range of $800 million. About 25 per cent of the total effort is devoted to the automotive industry. Regulatory initiatives are based on the Toxic Substance Management Policy 1995 Framework, and involve multi-stakeholder consultation to identify, evaluate and recommend goals, targets, and management options to reduce exposure to hexavalent chromium, maximize the recycling of nickel and minimize the releases of cadmium from industry operations by promoting and encouraging appropriate P2 practices. Other regulatory initiatives follow from the Fisheries Act of 1970, the Metal Finishing Liquid Effluent Guidelines of 1977, and the Canadian Environmental Protection Act of 1988. There are also non-regulatory initiatives, such as the Metal Finishing Industry Pollution Project, a voluntary cooperative effort directed towards formulating plans to reduce toxic effluents from metal finishing operations and to develop and implement site-specific P2 plans. The various treatment technologies such as physico-chemical treatment of multi-metal rinse waters and periodic bath dumpings at on-site waste water treatment plants, water reduction practices to make more effective use of rinse water, evaporation, ion exchange, packed bed scrubbers, fume suppressants, composite mesh pads and separate ventilation for degreasing are also described. Specific case studies are cited to illustrate the various treatment technologies.

  16. Bombardier Inc. Factory, Valcourt, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Hollick, J. [Solar Wall International Ltd., Downsview (Canada)


    Bombardier Inc. of Montreal, Canada has installed over 15,000 m{sup 2} of unglazed solar air collectors at its various manufacturing plants in Quebec. The solar collectors decrease operating expenses and significantly improve indoor air quality. Bombardier's engineers compared the cost of this system with other methods of recladding and improving ventilation and found the costs to be the same. With no extra costs for free solar heating, the system has an immediate payback, along with other benefits of improved air quality and attractive architecturally designed walls that utilize solar energy. Bombardier's first solar heating installation at their Sea Doo manufacturing plant has a solar wall area of 740 m{sup 2}. The heat-absorbing surface area is 611 m{sup 2} of a custom dark olive-green colour, with the balance being the white canopy plenum along the top and vertical dividers. The entire surface of the solar panel is separated into six sections with one fan per section. Wall-mounted ventilation fans were installed to bring in a total of 71,400 m{sup 3}/h of heated ventilation air. Monitored solar and destratification savings for the year 1993-94 were CA $33,000 (ECU 20,440) based on energy savings of 894,000 kWh. (author)

  17. The aeolian sedimentary system in the northern Qilian Shan and Hexi Corridor (N-China) - geomorphologic, sedimentologic and climatic drivers (United States)

    Nottebaum, Veit; Lehmkuhl, Frank; Stauch, Georg


    The formation of aeolian deposits depends on the influence of climatic factors but also on non-climatic controls, such as local geomorphological setting and tectonic activity. Unravelling the environmental history needs a careful consideration of a set of sections to capture spatial variability and a detailed investigation of depositing processes and chronology. Along the northern margin of the Qilian Shan mountain range 22 OSL-dated loess and aeolian sand sections and additional surface samples reveal the interactions between climatic, geomorphologic and sedimentologic factors. Thin loess covers (~1-2 m) occur in elevations of 2000 to 3800 m asl, which were mainly accumulated during the Holocene. End-member modelling of loess grain size data exhibits three dominant aeolian transport pathways representing local transport from fluvial storages, dust storm contribution and background dust deposition. Their relative contributions show a clear dependence on geomorphological setting, and additionally, synchronous trends throughout the Holocene. Their relative changes allow conclusions about Holocene environmental conditions. Discontinuous archives (aeolian sand, lacustrine, and alluvial deposition) in the lower forelands of the Qilian Shan show a distinct spatial pattern contrasting western and eastern forelands. The comparison of OSL ages exhibits high sediment accumulation (~2 m/ka) in the drier western part during the Late Glacial, while the lack of Holocene ages indicates sediment discharge / deflation. In contrast, moister areas in the eastern foreland yield scattered Holocene ages. This indicates high sediment dynamics, benefiting from fluvial reworking and thus provided sediment availability. Fluvial sediment supply plays an important role in sediment recycling. Meanwhile, western forelands lack efficient sand sources and fluvial reworking agents. The study exemplifies the complex sedimentary systems acting along mountain to foreland transects which often host

  18. Western Food in China

    Institute of Scientific and Technical Information of China (English)


    AS the Chinese saying goes, "Ask for local custom when you enter a foreign country." Western food’s first introduction to China in the 17th century was accompanied with its adoption to Chinese dining habits. Western food was introduced into China in large scale during the mid-19th and early 20th centuries. However, as early as the 17th century Western missionaries and envoys were introducing food from their homeland to upper-class Chinese as a means of paying tribute or

  19. Violence the Western way. (United States)

    Roth, B E


    Despite the quiet revolution in response to changing conceptualizations of gender in psychoanalysis, the Western has remained the domain of aggressive phallic masculinity. The iconic imagery of the Western, when combined with its narrative trajectory, is used to tell stories of violent encounters between men. The acceptance of the genre, and its duplication by other cultures and film makers, indicates that the Westerns' imagery and moral solutions tap into some basic deep structures of anxiety and pleasure in violence between men. As long as societies require subtle sublimations of aggressive and violent drives, it is likely that men will seek imaginary regressive experiences to discharge frustrations.

  20. Increasing turbine vendor competition in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Magee, J.T. [Emerging Energy Research, Cambridge, MA (United States)


    An overview of the wind turbine market in Canada was presented. Canada is now experiencing increased turbine vendor competition. Trends in wind turbine OEM market shares in Canada have increased from 10 per cent in 2000 to over 70 per cent in 2007. Several major companies in Canada have signed large-scale orders for delivery in 2010. It is expected that future wind turbine demands in all areas of Canada will increase. However, projections for Canadian wind growth demonstrate the difficulties provinces are now facing in trying to attract manufacturing investment away from the United States. Growth in wind turbine investment is in the process of creating a more robust North American wind turbine generator chain. However, the majority of new facilities are located in the United States. It is not known if Quebec's wind turbine generators will be viable outside of fulfilling Hydro-Quebec's tendering process. Canada's wind industry must consider equipment transport costs as well as a shortage of operating and maintenance service infrastructure. It was concluded that growth in the United States is expected to have a positive impact on Canadian wind energy customers. tabs., figs.

  1. Source characterisation of Sedimentary organic matter in mangrove ecosystems of northern Kerala, India: Inferences from bulk characterisation and hydrocarbon biomarkers

    Digital Repository Service at National Institute of Oceanography (India)

    Resmi, P.; Manju, M.N.; Gireeshkumar, T.R.; RatheeshKumar, C.S.; Chandramohanakumar, N.

    diagenesis of sedimentary organic matter. The elemental and isotopic ratios along with sedimentary chlorophyll a content, suggested substantial contribution of planktonic organic matter apart from mangrove/terrestrial derived organic matter. The sources...

  2. New paleomagnetic data from late Paleozoic sedimentary rocks of Novaya Zemlya Archipelago: tectonic implications (United States)

    Abashev, Victor V.; Metelkin, Dmitry V.; Mikhaltsov, Nikolay E.; Vernikovsky, Valery A.; Matushkin, Nikolay Yu.


    New paleomagnetic data for Novaya Zemlya archipelago were obtained by processing the samples collection gathered during the 2014 field season. The paleomagnetic directions and paleomagnetic poles were determined from the Paleozoic sedimentary complexes located on the Southern Island (Upper Permian) and the Northern Island (Lower and Upper Devonian, Upper Carboniferous) of the archipelago. Positive fold and reversal tests indicate that the isolated paleomagnetic directions correspond to the primary magnetization components. The corresponding paleomagnetic pole are in good agreement with poles obtained earlier in the 1980s by E.L. Gurevich and I.A. Pogarskaya. Considering the confidence ovals, the paleomagnetic poles obtained for the sites of the Northern Island are located close to the corresponding path segment of the APWP of Europe. This means that at least since the early Devonian, the northern part of Novaya Zemlya Archipelago had a position that was close to its current position relatively to the Arctic margin of Europe and has not undergone significant shifts or rotations. However, the upper Permian paleomagnetic pole for the Southern Island is very different from the corresponding part of the European APWP. We are considering this pole position within a model, involving significant intraplate movement between the structures of the European and Siberian tectonic provinces until the Late Cretaceous. The sinistral strike-slips inferred by the model could have caused or were accompanying the opening of the Mesozoic rift system in Western Siberia. This event has reached its maximum within the South Kara basin and resulted in the north-westward (in geographic coordinates) displacement of the southern part of the Novaya Zemlya Archipelago in relation to the Arctic margin of Europe and in the deformation of the Pay-Khoy-Novaya Zemlya margin, which caused its modern curved form. The study was supported by the Russian Science Foundation, grant No. 14-37-00030 and the

  3. Sedimentary organic matter characterization of the Triassic-Jurassic boundary GSSP at Kuhjoch (Austria) (United States)

    Ruhl, M.; Veld, H.; Kürschner, W. M.


    The Triassic-Jurassic (T-J) boundary interval coincides with enhanced extinction rates in the marine realm and pronounced changes in terrestrial ecosystems on the continents. It is further marked by distinct negative excursions in the δ13C org and δ13C carb signature that may represent strong perturbations of the global carbon cycle. We present integrated geochemical, stable-isotope and palynological data from the Kuhjoch section, the Global boundary Stratotype Section and Point (GSSP) for the base of the Jurassic (Northern Calcareous Alps, Austria). We show that the initial carbon isotope excursion (CIE), coinciding with the marine extinction interval and the formation of black shales in the western Tethys Eiberg Basin, is marked by only minor changes in kerogen type, which is mainly of terrestrial origin. Increased Total Organic Carbon (TOC) concentrations of 9% at the first half of the initial CIE coincide with Hydrogen Index (HI) values of over 600 mg HC/g TOC. The high correlation (with R2 = 0.93) between HI values and terrestrial Cheirolepidiaceaen conifer pollen suggests a terrestrial source for the hydrogen enriched organic compounds. The lack of major changes in source of the sedimentary organic matter suggests that changes in the δ13C org composition are genuine and represent true disturbances of the global C-cycle. The sudden decrease in total inorganic carbon (TIC) concentrations likely represents the onset of a biocalcification crisis. It coincides with a 4.5‰ negative shift in δ13C org values and possibly corresponds to the onset of CAMP related volcanic activity. The second half of the initial CIE is marked by the dramatic increase of green algae remains in the sediment. The simultaneous increase of the C org/N tot ratio suggests increased marine primary production at the final stage of black shale formation.

  4. Tectonic and Sedimentary Response of the Huangshan Basin to Paleo-Pacific Subduction undernearth Southeast China (United States)

    Xu, X.; Tang, S.; Lin, S.


    The subduction of the Paleo-Pacific Plate predominated the Late Mesozoic tectonic evolution of southeast China. This process is well documented by Jurassic-Cretaceous deposition and structural deformation. Zircon U-Pb ages of volcano-sedimentary rocks and fault-slip data of brittle faults were investigated in the Huangshan Basin. Detrital zircon U-Pb ages show that the provenances of the Huangshan Basin changed during Late Jurassic to Early Cretaceous. The source region of Early and Middle Jurassic sediments is mainly the Wuyishan domain to the southeast. But the Early Cretaceous clastic rocks are derived from the Jiangnan domain to the north. The inversions of fault-slip data show that paleostress fields also changed during Late Jurassic to Early Cretaceous. The strike-slip regime with nearly E-W compression and N-S extension predominated in the late Middle Jurassic whereas intense NW-SE-striking extensional one during Early Cretaceous. Moreover, geochemistry and zircon U-Pb ages of Late Jurassic (156~152 Ma) and Early Cretaceous (~130 Ma) felsic volcanic rocks in the Huangshan Basin also argue for a tectonic event occurred during Late Jurassic to Early Cretaceous. Above results imply that the tectonic background of southeast China changed from the initial subduction of the Paleo-Pacific plate during the Early and Middle Jurassic into subsequence back-arc extension in the Early Cretaceous. The paleostress field then changed into the strike-slip regime with N-S compression and E-W extension during late Early Cretaceous, which is caused by the collision between the Philippine and South China blocks. And after that, a weak and short-lived N-S extension was replaced by the strike-slip regime with NW-SE compression and NE-SW extension. Meanwhile, the South China continental margin also changed from an Andean-type to a Western Pacific-type plate boundary in early Late Cretaceous.

  5. Natural gas origins of large and medium-scale gas fields in China sedimentary basins

    Institute of Scientific and Technical Information of China (English)


    China sedimentary basins present abundant natural gas resource thanks to its unique geological settings.Marine highly-matured hydrocarbon source rocks,widespread coal-measure strata and low temperature Quaternary saline strata,etc.,indicate the wide foreground of China natural gas resources. Up to now,most of the petroliferous basins have been discovered to have wholesale natural gas accumulation from Precambrian,Paleozoic,Mesozoic to Cenozoic in the east,the central,the west and the coast of China.These large and medium-scale gas reservoirs are mainly composed of hydrocarbon gas with big dry coefficient,tiny non-hydrocarbon,wide carbon isotope distribution and varying origin types,the hydrocarbon gas includes coal-formed gas,oil-formed gas,biogenic gas and inorganic gas, etc.Coal-formed gas is the main type of China natural gas resources,in particular several explored large-scale gas fields(>100 billion cubic meter)of Kela 2,Sulige and Daniudi,etc.,they all belong to coal-formed gas fields or the gas fields consisting mostly of coal-formed gas.Oil-formed gas is also abundant in China marine basins,for example marine natural gas of Sichuan Basin generated from crude oil cracking gas.Primary and secondary biogenic gas fields were discovered respectively in the Qaidam Basin and Western Slope of Songliao Basin.In addition,inorganic gases are mainly distributed in the eastern China,in particular the Songliao Basin with abundant carbon dioxide accumulation,indicating that the eastern China present large exploration potential of inorganic gas.

  6. Origin of sedimentary organic matter at the Northern Cascadia Margin (United States)

    Kaneko, M.; Naraoka, H.


    Gas hydrate in marine sediments may have important roles on global carbon cycle and climatic change. We examined origins of sedimentary organic matter and bacterial activity in deep and hydrate-bearing sediment cored in Site U1327 and U1328 at northern Cascadia Margin by IODP Exp311, using σ13C of total organic carbon (TOC), σ15N of total nitrogen (TN), σ34S of total sulfur (TS), and σ13C of biomarkers in hydrocarbon fraction. In both sites, TOC/TN ratios and σ13C of TOC values ranged from 5.5 to 18.0 and -25.7 to -21.5 ‰, respectively, suggesting that sedimentary organic matter is a mixture of terrestrial and marine sources. Long chain (n)-alkanes (C27, C29, and C30), known as biomarkers of terrestrial higher plant were most abundant components (up to ~50 μg/gCorg) through down to 300 mbsf, and their σ13C values (-34.3 to -28.7 ‰) reveal their C3 plant origin. In addition, very long-chain alkene (C37) occurred in some sediments, which suggests the blooming by coccolithophore in the past. σ34S of TS values at both sites show large variation between -30 to +20 ‰. Most of σ34S of TS values were less than present σ34S value of seawater sulfate (+20.3 ‰). This is attributable to isotope fractionation during microbial sulfate reduction. Crocetenes including one double bond occurred in deep sediments with higher σ13C values (-23 ‰) than the reported σ13C values (< ~ -100 ‰, Elvert et al, 2000), providing possibility of heterotrophic archaea using marine organic matter as a carbon source. Pentamethylicosane (PMI) was detected in relatively high concentrations at 249 mbsf at Site U1328 and its σ13C value was -46.4 ‰. This PMI could be chemoautotrophic archaea in origin such as methanogen. Diploptene was also detected in most sediments with the σ13C value of -37 to -35 ‰, probably being characteristic of chemoautotrophic bacteria.

  7. Sedimentary Records of the Paleohurricane Activity in the Bahamas (United States)

    Wallace, E. J.; Donnelly, J. P.; Wiman, C.; Cashman, M.


    Hurricanes pose a threat to human lives and can cause significant destruction of coastal areas. This threat has become more pronounced with recent rises in sea level and coastal populations. Currently, there is a large degree of uncertainty surrounding future changes in tropical cyclone activity. This is due to the limitations of climate models as well as the scarcity and unreliability of the current observational record. With so much uncertainty surrounding the current projections of hurricane activity, it is crucial to establish a longer and more accurate historical record. This study uses sediment cores extracted from blueholes in the Bahamas to develop a record of intense hurricane landfalls in the region dating back more than a millennia. The collected cores were sectioned, split, and scanned on an X-ray fluorescence scanner to obtain a high resolution core profile of the sediments' elemental composition and to identify potential sedimentary structures. Age control of the samples was determined using radiocarbon dating, coarse fraction was measured every centimeter, and hurricane event bed frequency was established for each core. We assess the statistical significance of the patterns observed in the sedimentary record using a coupled ocean-atmosphere hurricane model to simulate storms representative of modern climatology. Cores extracted from two blue holes near South Andros Island provide approximately a 1600 year and a 600 year record respectively, with sedimentation rates exceeding 1 cm/year. Both records contain coarse grained event deposits that correlate with known historical intense hurricane strikes in the Bahamas within age uncertainties. The 1600 year record confirms previous hurricane reconstructions from the Caribbean indicating higher tropical cyclone activity from 500 to 1400 CE. In addition, these new high-resolution records indicate elevated intense hurricane activity in the 17th and 18th centuries CE, when activity is also elevated in lower

  8. Basement Fault Reactivation by Fluid Injection into Sedimentary Reservoirs (United States)

    Peter, Eichhubl; Fan, Zhiqiang; Zhu, Cheng


    Many suspected injection-induced earthquakes occur in crystalline basement rather than in the overlying sedimentary injection reservoir. To address why earthquakes nucleate in the basement rather than the injection layer we investigate the relationship between pore pressure diffusion, rock matrix deformation, and induced fault reactivation through 3D fully coupled poroelastic finite element models. These models simulate the temporal and spatial perturbation of pore pressure and solid stresses within a basement fault that extends into overlying sedimentary layers and that is conductive for flow along the fault but a barrier for flow across. We compare the effects of direct pore pressure communication and indirect poroelastic stress transfer from the injection reservoir to the fault on increasing the Coulomb failure stress that could reactivate the basement fault for normal, reverse, and strike-slip faulting stress regimes. Our numerical results demonstrate that volumetric expansion of the reservoir causes a bending of the fault near the injector and induces shear tractions along the downdip direction of the fault in the basement. These induced shear tractions act to increase the Coulomb failure stress for a normal faulting stress regime, and decrease the Coulomb failure stress for a reverse faulting regime. For a strike-slip faulting stress regime, the induced shear tractions increase the Coulomb failure stress both in the reservoir and basement. The induced normal traction on the fault reduces the Coulomb failure stress in all three tectonic regimes, but is larger in the reservoir than in the basement due to the more pronounced poroelastic effect in the reservoir. As a result, strike-slip stress regimes favor fault reactivation in the basement. Whereas the magnitude of the direct pore pressure increase exceeds the magnitude of induced poroelastic stress change, the poroelastic stress change increases the Coulomb failure stress in the basement fault for the normal

  9. Glacially induced stresses in sedimentary rocks of northern Poland (United States)

    Trzeciak, Maciej; Dąbrowski, Marcin


    During the Pleistocene large continental ice sheets developed in Scandinavia and North America. Ice-loading caused bending of the lithosphere and outward flow in the mantle. Glacial loading is one of the most prominent tectono-mechanical event in the geological history of northern Poland. The Pomeranian region was subjected several times to a load equivalent of more than 1 km of rocks, which led to severe increase in both vertical and horizontal stresses in the upper crustal rocks. During deglaciation a rapid decrease in vertical stress is observed, which leads to destabilization of the crust - most recent postglacial faults scarps in northern Sweden indicate glacially induced earthquakes of magnitude ~Mw8. The presence of the ice-sheet altered as well the near-surface thermal structure - thermal gradient inversion is still observable in NW Poland. The glacially related processes might have left an important mark in the sedimentary cover of northern Poland, especially with regard to fracture reopening, changes in stress state, and damage development. In the present study, we model lithospheric bending caused by glacial load, but our point of interest lies in the overlying sediments. Typical glacial isostatic studies model the response of (visco-) elastic lithosphere over viscoelastic or viscous asthenosphere subjected to external loads. In our model, we introduce viscoelastic sedimentary layers at the top of this stack and examine the stress relaxation patterns therein. As a case study for our modelling, we used geological profiles from northern Poland, near locality of Wejherowo, which are considered to have unconventional gas potential. The Paleozoic profile of this area is dominated by almost 1 km thick Silurian-Ordovician shale deposits, which are interbedded with thin and strong limestone layers. This sequence is underlain by Cambrian shales and sandstones, and finally at ~3 km depth - Precambrian crystalline rocks. Above the Silurian there are approximately

  10. Migration stopover ecology of western avian populations: A southwestern migration workshop (United States)

    Skagen, Susan K.; Melcher, Cynthia P.; Hazelwood, Rob


    The importance of migration stopover sites in ensuring that migratory birds successfully accomplish their journeys between breeding and non-breeding ranges has come to the forefront of avian research. Migratory birds that breed in western United States (US) and Canada and overwinter primarily in western Mexico migrate across the arid region of northern Mexico and southwestern US. Many of these migrants use lowland riparian stopover habitats, which comprise less than 0.1% of the western U.S. landscape. These habitats represent a significant conservation priority.

  11. Noble gases in CH 4-rich gas fields, Alberta, Canada (United States)

    Hiyagon, H.; Kennedy, B. M.


    The elemental and isotopic compositions of helium, neon, argon, and xenon in twenty-one CH 4-rich natural gas samples from Cretaceous and Devonian reservoirs in the Alberta, Canada, sedimentary basin were measured. In all but a few cases, radiogenic ( 4He, 40Ar, and 131-136Xe) and nucleogenic ( 21,22Ne) isotopes dominated. Based solely on the noble gas composition, two types of natural gas reservoirs are identified. One (Group B) is highly enriched in radiogenic-nucleogenic noble gases and varies little in composition: 3He /4He = 1.5 ± 0.5 × 10 -8, 40Ar /36Ar = 5000-6500 , 40∗Ar /4He = 0.10 , 136∗Xe /4He ~ 0.7 × 10 -9, and 21∗Ne /22∗Ne = 0.452 ± 0.041 (∗ denotes radiogenic or nucleogenic origin; all 4He is radiogenic). High nitrogen content with 4He /N 2 ~ 0.06 is also characteristic of Group B samples. The remaining samples (Group A) contain a radiogenic-nucleogenic component with a different composition and, relative to Group B samples, the extent of enrichment in this component is less and more variable: 3He /4He = 10-70 × 10 -8, 40Ar /36Ar Precambrian basement, consistent with a present-day mass flux into the overlying sedimentary basin. Inferred 40∗Ar /136∗Xe 4He ratios imply a basement source enriched in thorium relative to uranium and potassium (Th/U > 20). Combined, the overall lower total radiogenic-nucleogenic content of Group A reservoirs, the greater variability in composition, and the appearance of Group A noble gases in reservoirs higher in the sedimentary sequence relative to the underlying basement implies that the Group A radiogenic-nucleogenic noble gases are indigenous to the sediments. The most interesting aspect of the Group A noble gases are the very high 3He /4He ratios; ~ 10-70 times greater than expected if derived from average crust. The mantle, surface cosmogenic 3He production, cosmic dust, or production in a lithium-enriched environment as potential sources for the 3He excesses are evaluated. The present data set

  12. Croatian Language Maintenance in Canada

    Directory of Open Access Journals (Sweden)

    Ivana Petrović


    Full Text Available Although the topic of language maintenance has received considerable attention from linguists around the world, there are still many aspects of this language-contact phenomenon that could be examined further. This paper aims to contribute to the existing body of knowledge by exploring the state of Croatian as a heritage language in Canada. The aim of the paper is two-fold. The first is to describe the demographic characteristics of the Croatian community by investigating the number of people of Croatian descent and the number of Croatian speakers in Canada. The second, and more specific, aim of the paper is to provide an account of the state of Croatian as a minority language and examine the extent of language maintenance in the community. To accomplish the first objective, Canadian census data (1996, 2001, 2006, and 2011 was analyzed, with special focus on linguistic census data (number and age of Croatian speakers in Canada, mother tongue of people of Croatian descent, language most used at home, etc.. To accomplish the second objective, census data was supplemented with data from a questionnaire-based survey completed by members of the Croatian community in Toronto. The survey was completed by 220 participants; 110 first-generation Croatian Canadians and 110 second-generation Croatian Canadians. Two versions of the questionnaire were designed, one for first-generation participants and the other for second-generation participants. The great majority of items in the two versions were identical; each version contained questions about demographic characteristics, language use in everyday life, and self-perceived language proficiency in English and Croatian. The majority of questions were of a closed type (multiple-choice questions and rating scales, but there were also some open-ended questions, so as to give participants the opportunity to express their viewpoint or comment on certain issues. Questions were written in both Croatian and English

  13. New Constraints on Maar Geometry and Sedimentary Fill of Laguna Potrok Aike, Southern Patagonia (United States)

    Gebhardt, C. A.; Niessen, F.; Anselmetti, F.; Ariztegui, D.; de Batist, M.; Haberzettl, T.; Ohlendorf, C.; Zolitschka, B.


    Laguna Potrok Aike is located in Southern Patagonia, Argentina, at 52°S and 70°W. The maar lake has a diameter of 3.5 km and is almost circular and bowl-shaped with a deep, flat plain (100 m water depth) in its central part. Steep flanks separate the lake shoulders at 15 to 35 m water depth from the central plain. The lake is situated in the Pali Aike Volcanic Field at the present boundary between the Southern Hemispheric Westerlies and the Antarctic Polar Front. Its lake level is highly susceptible to changes in the Antarctic Circumpolar Current that controls the regional precipitation patterns. Its sedimentary infill possibly contains a long and continuous record of several glacial and interglacial cycles, which is unique in the southern South American realm. Two major stratigraphic units (I and II) were distinguished in the seismic sections. Unit I consists of the lacustrine infill and was further subdivided into Sub-units I-a and I-b on the lake shoulders and I-ab, I-c, and I-d in the central basin. Sub-units I-a and I-b on the lake shoulders are separated by a major unconformity and contain several paleoshoreline structures formed during a step-wise transgression after a lake level lowstand of approx. 35 m below the present lake level. In the central basin, Sub-units I-a and I-b are merged into Sub-unit I-ab, not being separated by any unconformity. Pelagic sedimentation dominates in the northern and central parts, whereas mass movement deposits were found in the southern, western and eastern parts close to the steep diatreme flanks. The boundary between I-ab and I-c is non-erosive with I-ab forming downlaps onto I-c from the eastern and western parts of the lake, pointing at a significantly lower lake level during its accumulation. Sub-unit I-d shows similar characteristics as I-ab. The bedrock (Unit II) that forms the steep diatreme flanks consists of the well-layered sandstones found in the lake surroundings.

  14. Sedimentary records on the subduction-accretion history of the Russian Altai, northwestern Central Asian Orogenic Belt (United States)

    Chen, Ming; Sun, Min


    The Russian Altai, comprising the northern segment of the Altai-Mongolian terrane (AM) in the south, the Gorny Altai terrane (GA) in the north and the intervening Charysh-Terekta-Ulagan-Sayan suture zone, is a key area of the northwestern Central Asian Orogenic Belt (CAOB). A combined geochemical and detrital zircon study was conducted on the (meta-)sedimentary sequences from the Russian Altai to reveal the tectono-magmatic history of these two terranes and their amalgamation history, which in turn place constraints on the accretionary orogenesis and crustal growth in the CAOB. The Cambrian-Ordovician meta-sedimentary rocks from the northern AM are dominated by immature sediments possibly sourced from intermediate-felsic igneous rocks. Geochemical data show that the sediments were likely deposited in a continental arc-related setting. Zircons separated from these rocks are mainly 566-475 Ma and 1015-600 Ma old, comparable to the magmatic records of the Tuva-Mongolian terrane and surrounding island arcs in the western Mongolia. The similar source nature, provenance and depositional setting of these rocks to the counterparts from the Chinese Altai (i.e., the southern AM) imply that the whole AM possibly represents a coherent accretionary prism of the western Mongolia in the early Paleozoic rather than a Precambrian continental block with passive marginal deposition as previously thought. In contrast, the Cambrian to Silurian (meta-)sedimentary rocks from the GA are characterized by a unitary zircon population with ages of 640-470 Ma, which were potentially sourced from the Kuznetsk-Altai intra-oceanic island arc in the east of this terrane. The low abundance of 640-540 Ma zircons (5%) may attest that this arc was under a primitive stage in the late Neoproterozoic, when mafic igneous rocks dominated. However, the voluminous 530-470 Ma zircons (95%) suggest that this arc possibly evolved toward a mature one in the Cambrian to early Ordovician with increasing amount of

  15. The Sedimentary Record of Sea-Level Change (United States)

    Coe, Angela L.; Bosence, Dan W. J.; Church, Kevin D.; Flint, Stephen S.; Howell, John A.; Wilson, R. Chris L.


    This unique textbook describes how past changes in sea-level can be detected through an analysis of the sedimentary record. In particular, it concentrates on the current sequence stratigraphy model. It explains this model from basics and shows how the model can be applied to both siliciclastic and carbonate successions. Designed for undergraduate and graduate courses in sequence stratigraphy, as well as for professional courses within the petroleum industry, this full-colour textbook includes numerous features that will aid tutors and students alike. These include detailed case studies demonstrating the practical applications of sequence stratigraphy and set-aside boxes providing supplementary and background information. Bulleted questions and answers are interspersed throughout the text, encouraging students to test their understanding of the material. The book is supported by a website hosting sample pages from the book, selected illustrations to download, and worked exercises. Written and developed over a number of years by a team of experts from the Open University Full colour throughout with superb illustrations Contains many pedagogical features that will appeal to students and tutors Supported by a website hosting sample pages, illustrations and worked exercises

  16. Land subsidence and hydrodynamic compaction of sedimentary basins

    Directory of Open Access Journals (Sweden)

    H. Kooi


    Full Text Available A one-dimensional model is used to investigate the relationship between land subsidence and compaction of basin sediments in response to sediment loading. Analysis of the model equations and numerical experiments demonstrate quasi-linear systems behaviour and show that rates of land subsidence due to compaction: (i can attain a significant fraction (>40% of the long-term sedimentation rate; (ii are hydrodynamically delayed with respect to sediment loading. The delay is controlled by a compaction response time τc that can reach values of 10-5-107 yr for thick shale sequences. Both the behaviour of single sediment layers and multiple-layer systems are analysed. Subsequently the model is applied to the coastal area of the Netherlands to illustrate that lateral variability in compaction-derived land subsidence in sedimentary basins largely reflects the spatial variability in both sediment loading and compaction response time. Typical rates of compaction-derived subsidence predicted by the model are of the order of 0.1 mm/yr but may reach values in excess of 1 mm/yr under favourable conditions.

  17. Edge detection in gravity field of the Gheshm sedimentary basin

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    Ali Akbar Hosseini


    Full Text Available Edge detection and edge enhancement techniques play an essential role in interpreting potential field data. This paper describes the application of various edge detection techniques to gravity data in order to delineate the edges of subsurface structures. The edge detection methods comprise analytic signal, total horizontal derivative (THDR, theta angle, tilt angle, hyperbolic of tilt angle (HTA, normalised total horizontal gradient (TDX and normalised horizontal derivative (NTHD. The results showed that almost all filters delineated edges of anomalies successfully. However, the capability of these filters in edge detection decreased as the depth of sources increased. Of the edge enhancement filters, normalized standard deviation filter provided much better results in delineating deeper sources. The edge detection techniques were further applied on a real gravity data from the Gheshm sedimentary basin in the Persian Gulf in Iran. All filters specified a northeast-southwest structural trend. The THDR better outlined the structural morphology and trend. Moreover, it indicated the salt plugs much better than other filters. Analytic signal and THDR successfully enhanced the edges of the shorter wavelength residual structures. Normalized standard deviation (NSTD, TDX and hyperbolic of tilt angle (HTA filters highlighted the likely fault pattern and lineaments, with a dominant northeast-southwest structural trend. This case study shows that the edge detection techniques provides valuable information for geologists and petroleum engineers to outline the horizontal location of geological sources including salt plugs and stand out buried faults, contacts and other tectonic and geological features.

  18. New Insights into the Sedimentary Dynamics along Carbonate Slopes (United States)

    Wunsch, Marco; Betzler, Christian; Lindhorst, Sebastian; Lüdmann, Thomas; Eberli, Gregor


    Hydroacoustic, sedimentological and seismic data of the leeward slope of Great Bahama Bank and the windward slope of the adjacent Cay Sal Bank provide new insights into carbonate platform slope sedimentation. Our study focuses on the diversity and complexity of the slope morphologies and sedimentary patterns which characterize the youngest high-frequency sequence, forming since the Last Glacial Maximum. It is shown that both carbonate platform slopes are dissected by furrows, gullies and channels which are genetically not related. Along the windward slope of Cay Sal Bank, toe of slope erosion, in conjunction with the local tectonic regime is responsible for channel incisions. Our data show that these channels were active during the regression after the last interglacial highstand of sea level. During this regression, downwelling transported platform sediment downslope, which was redistributed along the slope by contour currents. It is also shown that large mass transport complexes at the leeward slope of Great Bahama Bank formed during the last sea level lowstand, probably triggered by the release of pore-water pressure. These MTC created a complex slope morphology of gullies and scarps. These gullies act as a point source by confining the exported platform sediments during the present day sea level highstand.

  19. Igneous-sedimentary petroleum systems; Sistemas petroliferos igneo-sedimentares

    Energy Technology Data Exchange (ETDEWEB)

    Eiras, Jaime Fernandes [Para Univ., Belem, PA (Brazil)]. E-mail:; Wanderley Filho, Joaquim Ribeiro [PETROBRAS S.A., Manaus, AM (Brazil). Unidade de Negocios-BSOL]. E-mail:


    Igneous-sedimentary petroleum systems are mixed systems in which one or more essential elements or processes are related to magmatic events. Many examples worldwide are presented to show the importance of igneous rocks in the exploratory activities, as well as in the petroleum occurrence. Volcanic ash layers are of great importance in stratigraphic correlation and elucidation of structures, particularly when they occur in thick nonfossiliferous strata. They are also good indicators of turbidite deposition where turbidity currents are related to earthquakes generated by magmatic events. Unconventional reservoirs can be created by volcanic eruptions or intrusions, crystallization, reworking, and fracturing. Unaltered igneous rocks can seal vertically and laterally conventional reservoirs due to its excellent cap capacity. Abnormal thermal effect of igneous rocks can compensate the lack of overburden in shallow basins. Structural or combined traps can be formed due to intrusions, such as folded, faulted, and unconformity traps. Porosity can be either primary or secondary, or both. Primary porosity mainly consists of cavities produced by gas volatilization during eruption and cooling. Secondary porosity refers to those pores that result from hydrothermal alteration, recrystallization, and dissolution by groundwater, and tectonic stress. It includes intercrystalline pores formed by crystallization of various secondary minerals, dissolution pores, and tectonic fractures. New technologies of petroleum development and production are encouraging to search for oil and gas within igneous rocks, and new discoveries are expected. (author)

  20. Late Cenozoic sedimentary and tectonic history of south Buton, Indonesia (United States)

    Fortuin, A. R.; De Smet, M. E. M.; Hadiwasastra, S.; Van Marle, L. J.; Troelstra, S. R.; Tjokrosapoetro, S.

    A description and interpretation are given of the Upper Cenozoic sedimentary record of south Buton. Various sections and outcrops were studied and sampled for their microfossil content, to provide age and paleobathymetrical data. Together with information from the literature, these data from the base for a geohistory analysis to evaluate the vertical motions. Deposition started some 11 Ma ago, after the main deformation of the island, which was related to the collision of a microplate carrying Buton, with the southeast arm of Sulawesi. Coarse and fine terrigenous debris accumulated in a rapidly subsiding foreland basin; subsidence may have exceeded 100 cm/ka. When the rate of subsidence decreased a late Miocene-early Pliocene period of quiet pelagic sedimentation followed. From the late Pliocene onwards (around 3.5 Ma BP) an overall uplift took place, with rates between 30-120 cm/ka. This drastic change is explained by the collision of Buton with a submerged microcontinent that presently forms the Tukang Besi platform, situated southeast of Buton, which interaction resulted in wrench type tectonics and a clockwise rotation of over 60° for south Buton.

  1. Sedimentary records of mercury stable isotopes in Lake Michigan

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    Runsheng Yin


    Full Text Available Abstract Mercury (Hg concentrations and Hg isotopic composition were investigated in three sediment cores in Lake Michigan (LM. Two cores were collected from Green Bay, a region heavily impacted by Hg contamination and one core from an offshore region of LM absent of direct point source Hg. Historical trends of Hg influxes suggest increased Hg deposition began in the 1890s in Green Bay and in the early 1800’s in offshore LM. Recently deposited sediment reflecting more anthropogenic influence shows similar δ202 Hg values (-1.0 to -0.5‰ for all three cores however, deep core sediments, reflecting pre-industrial eras, show much lower δ202Hg values (-1.7 to -1.2‰. Using a binary mixing model based on δ202Hg signatures, the proportion of anthropogenic Hg was estimated. Model output confirms that Green Bay is more contaminated by local point source than the offshore LM. An increase in positive Δ199Hg values (-0.02 to +0.27‰ was observed from inner Green Bay to the offshore of LM, which may indicate increased input of atmospheric Hg and decreased watershed inputs along this transect. Overall, this study suggests that sedimentary Hg isotopes maybe a useful tracer in understanding Hg sources and history of Hg contamination in large lakes.

  2. Sedimentary environments of the Cenozoic sedimentary debris found in the moraines of the Grove Mountains, east Antarctica and its climatic implications

    Institute of Scientific and Technical Information of China (English)

    FANG Aimin; LIU Xiaohan; LEE Jong Ik; LI Xiaoli; HUANG Feixin


    During the field work of the 1998~1999's and 1999~2000's Chinese National Antarctic Research Expedition (CHNARE) in the Grove Mountains, east Antarctica, some Cenozoic sedimentary debris are found in two terminal moraine banks over the blue ice near Harding Mount in the center of this region. All the debris are of characteristics of glaciogenic diamicton and belong to the products of the glacial movements of the East Antarctic Ice Sheet. In this paper, the authors make a detailed study on the sedimentary environments of the sedimentary debris through petrologic, sedimentological, mineralogical, and geo-chemical methods. Characteristics of their sedimentary textures and structures, grain size distributions, quartz grains' surface textures and features, together with their geo-chemical compositions all show that these sedimentary rocks are a kind of subglacial lodgement tills which are deposited in the ice sheet frontal area by reactions of glacial movements and glaciogenic melt water. Their palaeoenvironmental implications in revealing the retreat history of East Antarctic Ice Sheet are discussed. The authors draw the conclusion from current study that the glacial frontal of the East Antarctica Ice Sheet might have been retreated to this area during the Pliocene Epoch, which represents a warm climate event accompanied by a large-scale ice sheet retreat in Antarctica at that time.

  3. Sedimentary environment, diagenesis and sequence stratigraphy of Sarvak Formation in Abteymour Oilfield in Western part of the Dezful embayment

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    H., Mehrabi,


    Full Text Available Sarvak Formation (Late Albian-Middle Turonian is one of the important reservoir units after Asmari (Oligo-Miocene in southwest Iran that host an important hydrocarbon reserves in this region. Due to facies and environmental variations as well as complex diagenetic history, its reservoir properties show intense complexity and heterogeneity. To understand these imposed heterogeneities a comprehensive reservoir study including facies analysis, diagenetic study and sequence stratigraphy are carried out. According to facies analysis study, carbonates of the Sarvakformation deposited in a homoclinal ramp-type platform. Low diversity of determined microfacies as well as mud-dominated facies in this field, indicating of a leeward ramp. Main diagenetic processes affected carbonates of this unit are extensive dissolution (in two step: eogenetic and telogenetic, dolomitization (in two ways: mixing zone and stylolite related, cementation (include meteoric, shallow and deep burial cements, micritization, mechanical and chemical compaction (stylolitization, dedolomitization, silicification, pyritization, recrystallization and fracturing. Paragenetic sequence of diagenetic events of this formation above and below Cenomanian-Turonian boundary showed two different histories for these two parts. Three 3rd ordered are recognized in sequence stratigraphic within the Sarvak Formation belong to Middle Cenomanian to Middle Turonian time span. Examining facies distribution patterns and diagenetic events in a sequence stratigraphic framework indicate close relationships and predictability of diagenetic alterations.

  4. Relations between sedimentary sequence and paleoclimatic changes during last 200 ka in the southern South China Sea

    Institute of Scientific and Technical Information of China (English)


    Core NS-93-5 was taken from the mild slope terrace of the southern South China Sea (SCS), which has preserved the steadiness depositional record of the normal marine environment since late Quaternary. Sedimentary sequence and oxygen isotopic stratigraphy of high resolution in the near 200 ka of the southern SCS has been established. By the comparative analysis with GISP2's ice core, the depositional record of D/O's events 1-21 and Heinrich's events H1-H6 in the southern SCS that reflected the quick climate change in short time scale since the last interglacial stage is revealed, which indicates that in the last 200 ka in the southern SCS and the Arctic area there was tele-connection of paleoclimate and the unstability of the Western Pacific Warm Pool. This note shows that the sedimentary layers order of this sea area classified by color identification and by oxygen isotope stratum has the very good corresponding relation. The color feature of sediment changes along with the climate and the former arranges a stagnant time of 1-1.5 ka generally. It was suggested that the paleoclimatic changes resulted in the rise and fall of sea level, the open and close of strait thoroughfare and the upwelling activity, which causes the changes of the oxidation-reduction condition of deep water along with the dynamic environment in this sea area, thus producing the different sediment features of sea bed. In addition, a volcanic ash layer, about 17 cm thick, has been found in the transition of oxygen isotope 4/5 stage, which is related with the Toba's volcanic eruption.

  5. Study of capillary absorption kinetics by X-ray CT imaging techniques: a survey on sedimentary rocks of Sicily

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    Tiziano Schillaci


    Full Text Available Sedimentary rocks are natural porous materials with a great percent of microscopic interconnected pores: they contain fluids, permitting their movement on macroscopic scale. Generally, these rocks present porosity higher then metamorphic rocks. Under certain points of view, this feature represents an advantage; on the other hand, this can constitute an obstacle for cultural heritage applications, because the porosity grade can lead to a deterioration of the lapideous monument for water capillary absorption. In this paper, CT (Computerized Tomography image techniques are applied to capillary absorption kinetics in sedimentary rocks utilized for the Greek temples as well as baroc monuments, respectively located in western and southeastern Sicily. Rocks were sampled near the archaeological areas of Agrigento, Segesta, Selinunte and Val di Noto. CT images were acquired at different times, before and after the water contact, using image elaboration techniques during the acquisition as well as the post-processing phases. Water distribution into porous spaces has been evaluated on the basis of the Hounsfield number, estimated for the 3-D voxel structure of samples. For most of the considered samples, assumptions based on Handy model permit to correlate the average height of the wetting front to the square root of time. Stochastic equations were introduced in order to describe the percolative water behavior in heterogeneous samples, as the Agrigento one. Before the CT acquisition, an estimate of the capillary absorption kinetics has been carried out by the gravimetric method. A petrographical characterization of samples has been performed by stereomicroscope observations, while porosity and morphology of porous have been surveyed by SEM (Scanning Electron Microscope images. Furthermore, the proposed methods have also permitted to define penetration depth as well as distribution uniformity of materials used for restoration and conservation of historical

  6. Only in Canada: A Study of National Market Potential for Christian Higher Education Canada (CHEC) Institutions (United States)

    Hiebert, Al


    In July 2007 Ipsos Reid delivered to Christian Higher Education Canada (CHEC) a report entitled "Christian Post-Secondary Education in Canada, Phase 3: Defining the Market". This article is a selective summary of the full 353-page report. It tabulates and analyzes findings from 1,000 phone interviews and 6,689 online surveys from six…

  7. Only in Canada: A Study of National Market Potential for Christian Higher Education Canada (CHEC) Institutions (United States)

    Hiebert, Al


    In July 2007 Ipsos Reid delivered to Christian Higher Education Canada (CHEC) a report entitled "Christian Post-Secondary Education in Canada, Phase 3: Defining the Market". This article is a selective summary of the full 353-page report. It tabulates and analyzes findings from 1,000 phone interviews and 6,689 online surveys from six population…


    Directory of Open Access Journals (Sweden)

    V. P. Semakin


    Full Text Available In terms of tectonics, the Deryugin basin (Fig. 1 is a part of the epi-Mesozoic Okhotsk plate comprising the heterogeneous basement that is mainly pre-Cenozoic (the lower structural stage and the sedimentary cover that is mainly represented by the Paleogenic-Neogenic-Quaternary deposits with the Upper Cretaceous sedimentary rocks observed locally without a visible hiatus (the upper structural stage.The acoustic basement (AB is composed of the metamorphosed Upper Cretaceous-Paleogenic silty-clayey-siliceous deposits (the western part of the region, amphibolites, gneisses, crystalline schists, weakly metamorphosed sandstones, siltstones, and mudstones (often siliceous, as well as intrusive and effusive rocks of basic, intermediate, and rarely persilic composition (the eastern part of the