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1
Jagoda, Kalinga, Bharat Maheshwari, and Gregory Gutowski. "Deer Creek Land Development (DCLD)." International Journal of Commerce and Management 22, no. 2 (June 22, 2012): 133–44. http://dx.doi.org/10.1108/10569211211239430.
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Yeager, Elizabeth A., and Sarah A. Stutzman. "Deer Creek Farms: Tradition into the Future." American Journal of Agricultural Economics 96, no. 2 (February 13, 2014): 598–605. http://dx.doi.org/10.1093/ajae/aat108.
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Spence, Brian C., and E. J. Dick. "Geographic variation in environmental factors regulating outmigration timing of coho salmon (Oncorhynchus kisutch) smolts." Canadian Journal of Fisheries and Aquatic Sciences 71, no. 1 (January 2014): 56–69. http://dx.doi.org/10.1139/cjfas-2012-0479.
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The environmental cues that regulate smoltification and trigger downstream movement by salmon should vary across space in response to differences in the predictability of favorable conditions for migration and ocean entry. To examine this, we modeled the short-term outmigration probability of four coho salmon (Oncorhynchus kisutch) populations in three distinct geographic regions in relation to photoperiod, temperature, streamflow, lunar phase, and interactions among these variables. For smolts in Deer and Flynn creeks, Oregon (1960–1972), migration probability was influenced by numerous factors, including photoperiod, temperature (absolute and change), flow (absolute and change), and lunar phase, with certain factors interacting. Smolts from Carnation Creek, British Columbia (1972–1986) responded to a similarly diverse suite of factors (excluding lunar phase), though in somewhat different ways. In contrast, migration timing of smolts in Sashin Creek, Alaska (1959–1969) was best explained by a model that included only photoperiod, temperature, and the interaction between these terms. These population differences suggest fundamental differences across regions in the selection processes operating in both marine and freshwater environments.
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Beschta, Robert L., and William J. Ripple. "INCREASED WILLOW HEIGHTS ALONG NORTHERN YELLOWSTONE's BLACKTAIL DEER CREEK FOLLOWING WOLF REINTRODUCTION." Western North American Naturalist 67, no. 4 (December 2007): 613–17. http://dx.doi.org/10.3398/1527-0904(2007)67[613:iwhany]2.0.co;2.
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Casbeer, Warren, Gustavious Williams, and M. Borup. "Phosphorus Distribution in Delta Sediments: A Unique Data Set from Deer Creek Reservoir." Hydrology 5, no. 4 (October 11, 2018): 58. http://dx.doi.org/10.3390/hydrology5040058.
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Recently, Deer Creek Reservoir (DCR) underwent a large drawdown to support dam reconstruction. This event exposed sediments inundated by the reservoir, since dam completion in the early 1940s. This event allowed us to take sediment data samples and evaluate them for phosphorous (P) content. It is difficult for normal reservoir sediment studies to have sediment samples at high spatial resolution because of access. During the drawdown, we collected 91 samples on a grid 100 m in one direction and 200 m in the other. This grid defined an area of approximately 750,000 m2 (185 acre). We took both surface samples, and at some sites, vertical samples. We determined water soluble P for all the samples, and P in four other reservoirs or fractions for 19 samples. Results showed water soluble P in the range of 2.28 × 10−3 to 9.81 × 10−3, KCl-P from 2.53 × 10−3 to 1.10 × 10−2, NaOH-P from 5.30 × 10−2 to 4.60 × 10−1, HCl-P from 1.28 × 10−1 to 1.34, and residual (mostly organic) P from 8.23 × 10−1 to 3.23 mg/g. We provide this data set to the community to support and encourage research in this area. We hope this data set will be used and analyzed to support other research efforts.
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Kelly, A. J., E. Karl Sauer, S. L. Barbour, E. A. Christiansen, and R. A. Widger. "Deformation of the Deer Creek bridge by an active landslide in clay shale." Canadian Geotechnical Journal 32, no. 4 (August 1, 1995): 701–24. http://dx.doi.org/10.1139/t95-069.
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Two parallel, concurrently active slip surfaces of a landslide in clay shale of the Cretaceous Lea Park Formation are causing deformation of a bridge structure across the North Saskatchewan River near Deer Creek, Saskatchewan. The upper slip occurs at the contact between the shale and glacial deposits, which is common in this region. However, the second slip occurs deep in the shale, 24 m below the upper slip zone. This multilevel landslide mechanism, not reported previously in this region, is resulting in a complex deformation pattern where components of the structure are moving at different rates. The multilevel slip mechanism is related to a unique combination of the hydrogeology and geologic structure at this site. Under an upward groundwater gradient, slip surfaces occur at discontinuities in available shearing resistance at different elevations in the shale. The discontinuities are gouge zones in the clay shale, which are the result of a combination of glacial shear and regional tectonism where parameters have been reduced to a residual state ([Formula: see text] and c′ = 0). The pore-water pressures for the slope stability analysis were generated from a site specific finite element seepage model using boundary conditions determined from a regional finite element seepage model. The groundwater models were calibrated from piezometer data and from hydrochemistry of water from farm wells, piezpmeters, and natural surface ponds. The hydrochemistry was used to delineate groundwater, discharge areas from recharge areas. The validity of the landslide mechanism is supported by a stability analysis integrated with the finite element seepage analysis, which demonstrates that two separate parallel slip surfaces at different depths can be at a state of limiting equilibrium concurrently. Key words : bridge deformation, Cretaceous shale, integrated models, residual strength, multilevel slips.
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Goodrich, R. R., J. F. T. Agapito, C. Pollastro, and L. J. Lafrentz. "Longwall mining through a graben with anomalous stresses at the deer creek mine." International Journal of Rock Mechanics and Mining Sciences 35, no. 4-5 (June 1998): 401–2. http://dx.doi.org/10.1016/s0148-9062(98)00038-2.
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Rains, R. Bruce, James A. Burns, and Robert R. Young. "Postglacial alluvial terraces and an incorporated bison skeleton, Ghostpine Creek, southern Alberta." Canadian Journal of Earth Sciences 31, no. 10 (October 1, 1994): 1501–9. http://dx.doi.org/10.1139/e94-133.
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Ghostpine Creek near Three Hills, southern Alberta, is a tributary of the Red Deer River. It has three sets of paired alluvial terraces (T-1 to T-3) in a downstream part of the valley. The rare discovery of a largely intact skeleton of plains bison (Bison bison bison) in a T-2 point bar prompted terrace mapping, 14C dating, and interpretation of the postglacial evolution of the valley. Downvalley portions of the creek began incision into the newly drained bed of glacial Lake Drumheller probably about 13 000 BP. Localized valley deepening up to 20 m, the production of erosional benches and residual spurs, and the development of partly convex-up creek paleothalwegs occurred between about 13 000 and 7600 BP, by which time basal T-1 alluvium was beginning to accumulate. Subsequent aggradation of T-1 sediment and then degradation of about 3–4 m were followed by aggradation of T-2 alluvium. These trends had taken place by 2600 BP, when the bison died and its skeletal remains were buried in uppermost sediment of a T-2 point bar. Between 2600 BP and now, the creek incised about 5 m below the former T-2 channel position and aggraded, partly synchronously, up to 3 m of T-3–floodplain alluvium. Radiocarbon-dated alluvial terrace sequences in Alberta show generally comparable trends of rapid early creek incision followed by partially overlapping episodes of net aggradation and degradation from basin to basin. However, such episodes were not closely synchronized between basins.
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Natkaniec-Nowak, Lucyna, Magdalena Dumańska-Słowik, Adam Gaweł, Anna Łatkiewicz, Joanna Kowalczyk-Szpyt, Anna Wolska, Stanislava Milovská, Jarmila Luptáková, and Karolina Ładoń. "Fire agate from the Deer Creek deposit (Arizona, USA) – new insights into structure and mineralogy." Mineralogical Magazine 84, no. 2 (February 5, 2020): 343–54. http://dx.doi.org/10.1180/mgm.2020.8.
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AbstractFire agates from Deer Creek are highly appreciated gemstones due to the presence of optical phenomena and rainbow colours that cause fiery effects to be observed on their characteristic brown base. The specific morphology of poorly ordered chalcedony (crystallinity index = 0.1–1.5) with an admixture of mogánite (av. 6.6%), micro-quartz and opal-C forming a colloform texture seems to be responsible for the presence of fire effect in these agates. The multi-layered silica spheroidal forms (‘bubble’-like structure), already noted in hand specimens, could be the centres of reflection and interference of white light. Numerous, microscopic inclusions of Fe and Ti compounds randomly scattered within some silica zones, together with microstructural features of agate, could determine the colour and size of the domains with the optical effect. Deer Creek fire agates form veins within their host volcanic rocks. The silica mineralisation filling the network of fissures in the host rocks was supplied cyclically with aqueous fluids of varying composition, enriched periodically in CO2, Fe, Ti, Mn, Zn and Ca. As a result, the red-brown colour of fire agates was created by scattered pigments of tiny iron oxides (magnetite, maghemite) and titanium oxides (rutile, anatase) within the silica matrix. The precipitation of strongly disordered silica with a characteristic colloform texture is diagnostic for boiling processes in this area.
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Trabert, Sarah. "Partners and Power: Understanding Ancestral Wichita and French Trade at the Deer Creek Site." International Journal of Historical Archaeology 23, no. 2 (August 27, 2018): 444–61. http://dx.doi.org/10.1007/s10761-018-0473-2.
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Hall, Russell L. "New Lower Jurassic ammonite faunas from the Fernie Formation, southern Canadian Rocky Mountains." Canadian Journal of Earth Sciences 24, no. 8 (August 1, 1987): 1688–704. http://dx.doi.org/10.1139/e87-162.
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New ammonite faunas are described from sections along Bighorn and Scalp creeks in central-western Alberta where Lower Jurassic parts of the Fernie Formation are exposed. The first record of the upper Sinemurian Obtusum Zone from the Fernie is based on the occurrence of Asteroceras cf. stellare and Epophioceras cf. breoni in the basal pebbly coquina on Bighorn Creek. The overlying Red Deer Member has yielded Amaltheus cf. stokesi, representing the upper Pliensbachian Margaritatus Zone; in immediately superjacent strata the first North American examples of ?Amauroceras occur together with Protogrammoceras and ?Aveyroniceras. In the basal parts of the overlying Poker Chip Shale a fauna including Harpoceras cf. falciferum, Harpoceratoides, Polyplectus cf. subplanatus, Hildaites cf. serpentiniformis, and Dactylioceras cf. athleticum is correlated with the lower Toarcian Falciferum Zone.The upper parts of the Poker Chip Shale on Fording River in southeastern British Columbia contain a fauna representing some part of the upper Toarcian, but owing to poor preservation, generic identifications are only tentatively made.
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Dixon, Kelly J., Shannon A. Novak, Gwen Robbins, Julie M. Schablitsky, G. Richard Scott, and Guy L. Tasa. "“Men, Women, and Children Starving”: Archaeology of the Donner Family Camp." American Antiquity 75, no. 3 (July 2010): 627–56. http://dx.doi.org/10.7183/0002-7316.75.3.627.
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In spring of 1846, the George and Jacob Donner families and some 80 traveling companions began their overland trek to California. When the party ascended the Sierra Nevada in late October, a snowstorm forced the group to bivouac. At this point, the train became separated into two contingents; the larger party camped near Donner Lake and the smaller group—including the Donner families—settled at Alder Creek. Though written accounts from the Lake site imply many resorted to cannibalism, no such records exist for Alder Creek. Here we present archaeological findings that support identification of the Alder Creek camp. We triangulate between historical context, archaeological traces of the camp, and osteological remains to examine the human condition amid the backdrops of starvation and cannibalism. A stepped analytical approach was developed to examine the site’s fragmentary bone assemblage (n= 16,204). Macroscopic and histological analyses indicate that the emigrants consumed domestic cattle and horse and procured wild game, including deer, rabbit, and rodent. Bladed tools were used to extensively process animal tissue. Moreover, bone was being reduced to small fragments; pot polish indicates these fragments were boiled to extract grease. It remains inconclusive, however, whether such processing, or the assemblage, includes human tissue.
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Eberth, David A., and Sandra L. Kamo. "First high-precision U–Pb CA–ID–TIMS age for the Battle Formation (Upper Cretaceous), Red Deer River valley, Alberta, Canada: implications for ages, correlations, and dinosaur biostratigraphy of the Scollard, Frenchman, and Hell Creek formations." Canadian Journal of Earth Sciences 56, no. 10 (October 2019): 1041–51. http://dx.doi.org/10.1139/cjes-2018-0098.
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The Battle Formation (BFm) is a widespread Upper Cretaceous marker horizon in western Canada that records a time of low sediment input and marks the boundary between the Edmontonian and Lancian land-vertebrate ages. Here, we present the first high-precision U–Pb CA–ID–TIMS age of 66.936 ± 0.047/0.060/0.140 Ma for the Battle bentonite, an altered vitric ash in the upper portion of the BFm at Knudsen’s Farm in the Red Deer River valley of Alberta. This age supersedes those previously reported, confirms that rates of sediment accumulation for the formation were very low (∼1.40 cm/ka), and allows us to interpolate an age range of ∼66.88–67.20 Ma for the BFm. Our data also provide a maximum age of ∼66.88 Ma for the base of the overlying Scollard Formation, a dinosaur-rich unit. We combine our age data with calibrated magneto- and palynostratigraphic data to assess chronostratigraphic correlations among the Scollard Formation of Alberta, the Frenchman Formation of Saskatchewan, and the Hell Creek Formation in eastern Montana. Whereas the combined data support previous interpretations that equate the age ranges of the Scollard Formation, Frenchman Formation, and the upper one third of the Hell Creek Formation in eastern Montana, they also indicate that all of the lower one third (L3) and part of the middle one third (M3) of the Hell Creek Formation in Montana are chronostratigraphically equivalent to all or part of the sub-BFm unconformity and the BFm in Alberta. Accordingly, a minimum age of ∼67.20 Ma is assessed for the base of the Hell Creek Formation in its type area.
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Jackson, L. J. "New Evidence for Early Woodland Seasonal Adaptation from Southern Ontario, Canada." American Antiquity 51, no. 2 (April 1986): 389–401. http://dx.doi.org/10.2307/279953.
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Radiocarbon dated features at the newly investigated Dawson Creek site in southern Ontario, Canada, document recurrent Amerindian occupations between the ninth and fifth centuries B.C. Artifactual, botanical, and faunal remains from six hearths evidence consistent fall season visits by task groups using Vinette 1 ceramics. Indicated reliance on nut-collecting and deer-hunting is duplicated at small Early Woodland sites elsewhere in Ontario and the Great Lakes region. Early thick ceramic types are clearly associated with scheduled seasonal activities. Possible differentiation of artifact assemblages by site function and season underscores the need for more discriminating definition of Early Woodland culture in the Northeast.
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Leith, Elizabeth A. "European Trade Goods on the Southern Plains: The Bryson-Paddock (34KA5) and Deer Creek (34KA3) Sites." Plains Anthropologist 53, no. 208 (November 2008): 551–64. http://dx.doi.org/10.1179/pan.2008.038.
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Jollimore, Troy. "“Some Version of the Same River”." Boom 4, no. 3 (2014): 36–45. http://dx.doi.org/10.1525/boom.2014.4.3.36.
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Photographer Byron Wolfe traveled to Deer Creek in California to capture the locations of a series of photographs of Ishi, “the last wild Indian in North America,” taken in 1914. His purpose was to show what had changed in the intervening century, to pose questions about the original photographers’ intentions and choices, whether and in what sense they took the results to be “authentic” portraits of Ishi’s earlier life, and what they wanted people to find in, and take away from, the pictures they took. Wolfe’s photographs juxtaposed with the originals accompany an essay by Troy Jollimore, a meditation on Ishi’s legacy, wilderness, and how the art and artifice of photography helps us make sense of people, place, and history.
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Baadsgaard, H., J. F. Lerbekmo, and I. McDougall. "A radiometric age for the Cretaceous–Tertiary boundary based upon K–Ar, Rb–Sr, and U–Pb ages of bentonites from Alberta, Saskatchewan, and Montana." Canadian Journal of Earth Sciences 25, no. 7 (July 1, 1988): 1088–97. http://dx.doi.org/10.1139/e88-106.
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Bentonites associated with coal seams at the North American Cretaceous–Tertiary (K–T) boundary in the Red Deer Valley of Alberta, in the Frenchman Valley of Saskatchewan, and near Hell Creek, Montana, were dated by the K–Ar, Rb–Sr, and U–Pb methods. Based upon palynological stratigraphic correlation and the presence of a sharp iridium anomaly, the three sampled bentonite horizons all occur less than 1 m above the established K–T boundary. There is evidence of possible systematic errors giving dating results outside nominal statistical error values. Despite possible constant errors, the weighted mean of nine average dates is calculated as 64.3 ± 1.2 Ma (2σ standard deviation). An unweighted averaging produces a grand mean age of 64.4 ± 1.2 Ma.
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Williams, Gustavious Paul, and Ashley Childers Walton. "Method for Estimating Sediment Mass Movement from Delta Recutting: A Case Study Using Single Beam Sonar in Deer Creek Reservoir." Water 11, no. 11 (October 25, 2019): 2222. http://dx.doi.org/10.3390/w11112222.
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The recutting of delta sediments typically occurs during reservoir drawdown in the summer months. It can affect various reservoir processes and can impact water quality because of resuspending nutrients during warm periods supports phytoplankton growth. Quantifying this sediment movement is a key element for evaluating the life and quality of a reservoir. This study targets reservoirs in the intermountain region of the U.S. These reservoirs are filled in the spring, then drawdown through the summer to provide irrigation water. Incoming sediment loads are generally restricted to spring high flows, with little new sediment entering the reservoirs during the remainder of the year. As the reservoirs undergo drawdown, the sediment deposited in the delta region during spring flows is re-cut from the exposed delta and moved into submerged delta region. The majority of flow and sediment movement both above and below the water surface occurs in channels cut into the sediments during spring deposition. During recutting, channels in the exposed sediments often move, but the submerged channels are more stationary. Traditional single-beam sonar surveys are performed on a grid and changes are used to quantify sediment movements. This approach is not applicable to delta recutting as the grid resolution is not sufficient to resolve the relevant changes that occur in the narrow excised flow channels. This study explores the ability to quantify and monitor sediment mass movement in Deer Creek Reservoir (DCR) using a single beam sonar. Our method uses surveyed cross-sections across the flow channels. It is difficult to position boat passes exactly on previous survey lines, and small location differences in an up-stream or down-stream location can be significant because of the slope of the channel. To address this, we surveyed each line in two directions, then interpolated both the position and elevation data. We performed periodic surveys over a two-month period. We were able to document and quantify both sediment deposition and erosion areas. As expected, sediment movement was from the inlet areas toward the reservoir. The data showed both deposition and erosion depending on the distance from the reservoir head, which changed over the survey period. This method can be used to quantify sediment recutting and resuspension that can affect nutrient loads during critical warm, low-reservoir conditions, but is difficult to implement accurately.
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Ehasz, Joseph, and Michael Pavone. "Discussion of “ Design of Deer Creek Damp ” by Harold Hollingsworth, Timothy R. Conner, and Victor E. Anderson (pp. 541–558)." Journal of Geotechnical Engineering 113, no. 10 (October 1987): 1269–71. http://dx.doi.org/10.1061/(asce)0733-9410(1987)113:10(1269).
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Hollingsworth, Harold, Timothy R. Conner, and Victor E. Anderson. "Closure to “ Design of Deer Creek Damp ” by Harold Hollingsworth, Timothy R. Conner, and Victor E. Anderson (pp. 541–558)." Journal of Geotechnical Engineering 113, no. 10 (October 1987): 1271–75. http://dx.doi.org/10.1061/(asce)0733-9410(1987)113:10(1271).
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Li, Qiang, Hezhong Yuan, Hui Li, Dengjun Wang, Yan Jin, and Deb P. Jaisi. "Loading and Bioavailability of Colloidal Phosphorus in the Estuarine Gradient of the Deer Creek‐Susquehanna River Transect in the Chesapeake Bay." Journal of Geophysical Research: Biogeosciences 124, no. 12 (December 2019): 3717–26. http://dx.doi.org/10.1029/2019jg005135.
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Lerbekmo, J. F. "The Dorothy bentonite: an extraordinary case of secondary thickening in a late Campanian volcanic ash fall in central Alberta." Canadian Journal of Earth Sciences 39, no. 12 (December 1, 2002): 1745–54. http://dx.doi.org/10.1139/e02-079.
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The late Campanian (~73 Ma) Dorothy bentonite outcrops in the marine Bearpaw Shale for 20 km along the Red Deer River valley east of Drumheller, Alberta, and is up to 13.5 m thick. An isopach map based upon 230 sub surface and surface thickness measurements illustrates an elongated southwestnortheast lobe with maximum dimensions of about 300 km by 50 km. The volume is ~57 km3 distributed within an area of ~11 000 km2. This bentonite is the altered product of what is believed to be a short-lived Plincan-type eruption from part of the Howell Creek Instrusives in southeastern British Columbia. Fortuitous preservation of the original ash in an up to 2.5 m thick calcite-cemented tuffaceous zone near the middle of the bentonite shows the original ash to have been >99% glass shards and pumice. The remainder of the ash is a crystal component consisting mostly of plagioclase and biotite. The silica content of the isotropic glass shards of about 77%, and a refractive index of 1.503 ± 0.001, suggest a magma of rhyolitic composition.
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Lynch, Elizabeth A., and Anna Burke Weckwerth. "Herbaceous Vascular Flora Of Forested Seep Wetlands In Winneshiek County, Iowa, USA." Journal of the Iowa Academy of Science 124, no. 1-4 (January 1, 2017): 1–10. http://dx.doi.org/10.17833/0896-8381-124.1-4.1.
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Forested seep wetlands dominated by skunk cabbage (Symplocarpus foetidus) occur frequently in the Canoe Creek watershed of the Upper Iowa River, but this type of wetland has not been described systematically in the upper Midwest. The goal of this study is to document the herbaceous plant flora of five seeps. Although individual seeps are small (200-500 m2), they provide habitat for a high number of plant species. Five seeps with total area less than 0.2 ha supported more than 120 native vascular herbaceous taxa, 20 of which have a coefficient of conservatism (C-value) of 7 or higher and 23 that are obligate wetland species. Several species that were common in these habitats 100 years ago appear to have been locally extirpated or have become uncommon in the region, including Gentianopsis crinita, Cirsium muticum, Eupatorium altissimum, Chelone glabra, and Micranthes pensylvanica. Today, these plant communities are threatened by invasive plant species, high levels of deer herbivory, and destruction by human activities. We hope that by documenting their current species composition we can inspire protection of these wetlands and provide a baseline for monitoring future changes.
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Parker, Israel D., Roel R. Lopez, Reema Padia, Meghan Gallagher, Raghupathy Karthikeyan, James C. Cathey, Nova J. Silvy, and Donald S. Davis. "Role of free-ranging mammals in the deposition of Escherichia coli into a Texas floodplain." Wildlife Research 40, no. 7 (2013): 570. http://dx.doi.org/10.1071/wr13082.
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Context The role of wildlife in faecal pollution of water bodies (deposition of Escherichia coli (E. coli)) is not well understood. Current water-quality and land-use planning research largely relies on unreliable wildlife data (e.g. poor sourcing of abundance estimates, population density estimates applied to multiple fundamentally different areas, suspect or insufficiently described data collection techniques) Aims Our goal for the present research was to investigate deposition of E. coli into a floodplain by free-ranging mammals. Objectives of the research were to determine the density of important free-ranging meso- and large mammals in the study area, determine faecal E. coli loads for each species, and evaluate spatial data on species-specific faecal deposition. Methods We conducted our research in south-eastern Texas, USA, on two cattle ranches bisected by Cedar Creek (44-km long). Cedar Creek has elevated E. coli concentrations. We conducted mark–recapture and mark–resight population density estimates (2008/09) for meso- and large mammals in the study areas. We collected faecal samples from all captured wildlife. We also conducted transects through the study area to determine faecal-deposition patterns. Key results We found that raccoons (Procyon lotor), wild pigs (Sus scrofa), Virginia opossums (Didelphis virginiana) and white-tailed deer (Odocoileus virginianus) all had substantial faecal E. coli loads and population densities, thus implying an important role in E. coli deposition into the study floodplain. All species were widely distributed through the floodplain. Conclusions Free-ranging mammals contribute E. coli to floodplains and potentially affect water quality. We determined that four species commonly found in floodplains throughout North America all contributed E. coli to the study floodplain, thus implying mammal E. coli contributions in many locations and this is potentially important for E. coli management. Implications Improved locally specific mammal population estimates and estimates of locally derived E. coli concentration will improve floodplain and water-quality models that often depend on data of various quality. Additionally, our analyses demonstrated the need for continued research into the role of wildlife in E. coli deposition.
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McKnight, Diane M., Kenneth E. Bencala, Gary W. Zellweger, George R. Aiken, Gerald L. Feder, and Kevin A. Thorn. "Sorption of dissolved organic carbon by hydrous aluminum and iron oxides occurring at the confluence of Deer Creek with the Snake River, Summit County, Colorado." Environmental Science & Technology 26, no. 7 (July 1992): 1388–96. http://dx.doi.org/10.1021/es00031a017.
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Kuzyk, Gerald W., Jeff Kneteman, and Fiona K. A. Schmiegelow. "Pack Size of Wolves, Canis lupus, on Caribou, Rangifer tarandus, Winter Ranges in Westcentral Alberta." Canadian Field-Naturalist 120, no. 3 (July 1, 2006): 313. http://dx.doi.org/10.22621/cfn.v120i3.321.
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We studied pack size of Wolves (Canis lupus) on Woodland Caribou (Rangifer tarandus caribou) winter ranges in westcentral Alberta. These Caribou winter ranges are experiencing increasing pressure from resource extraction industries (forestry, energy sector) and concerns have been raised regarding increased Wolf predation pressure on Caribou in conjunction with landscape change. Thirty-one Wolves, from eight Wolf packs, were fitted with radiocollars on two Caribou winter ranges in the Rocky Mountain foothills, near Grande Cache, Alberta (2000-2001). There was a mean of 8.2 Wolves/pack and between 30 and 39 Wolves on each of the RedRock/Prairie Creek and Little Smoky Caribou ranges. The average pack size of Wolves in this region does not appear to have increased over that recorded historically, but the range (5-18) in the number of Wolves per pack varied considerably over our study area. Wolves preyed predominately on Moose (Alces alces), averaging one Moose kill every three to five days. There was some indication that pack size was related to prey size, with the smallest pack preying on Deer (Odocoileus spp.). It was clear that Caribou could not be the primary prey for Wolves, due to their low numbers, and relative to the pack size and Wolf kills we observed.
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Hall, Russell L. "New, biostratigraphically significant ammonites from the Jurassic Fernie Formation, southern Canadian Rocky Mountains." Canadian Journal of Earth Sciences 43, no. 5 (May 1, 2006): 555–70. http://dx.doi.org/10.1139/e06-004.
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Jurassic ammonites described here for the first time come from numerous localities in the Fernie Formation in the Foothills and Front Ranges of the Rocky Mountains of north- and south-eastern British Columbia and central- and south-western Alberta, and provide useful new age data for several members of the formation. The occurrence of Orthodactylites sp. in the uppermost beds of the Red Deer Member indicates this unit extends upwards into the basal Toarcian, which will be helpful in the search for carbon-isotope excursions associated with the early Toarcian anoxic event. The presence of Hettangian and lower Pliensbachian strata in outcrop of the Gordondale Member is confirmed. Diversity of the ammonite fauna in the Grey Beds is enlarged by the presence of ? Kepplerites ? Cadomites and Choffatia spp. These faunas also provide biostratigraphic constraints for carbon- and oxygen-isotope trends and UPb ages recently recorded from the Highwood Member and Grey Beds exposed in Bighorn Creek and its eastern tributary, and in Fording River. The first occurrence of Zemistephanus richardsoni from cratonic rocks, recorded here, suggests close proximity of the allochthonous terranes Wrangellia and Stikinia, the only other areas from which this species is known, to the northwest North American craton by early Bajocian time. One new species, Cardioceras (Subvertebriceras) ferniensis, is described.
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Rodriguez, Alisha, Andrew Calderwood, Brad T. Gooch, Maribeth Kniffin, and Laura Foglia. "Determining initial viability of local scale managed aquifer recharge projects in alluvial deposition systems." Acque Sotterranee - Italian Journal of Groundwater 10, no. 2 (June 24, 2021): 7–18. http://dx.doi.org/10.7343/as-2021-500.
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Critical groundwater overdraft is one of the greatest water issues of our time. In California, decades of overdraft have resulted in the passage of the 2014 Sustainable Groundwater Management Act, which requires critically overdrafted groundwater basins to create groundwater sustainability plans for future groundwater management. Many managers are using managed aquifer recharge (MAR) in their overall sustainability portfolio, in an attempt to balance groundwater use. Soil maps have been used in the past to determine viability of managed aquifer recharge sites. However, soil maps do not account for the high permeability pathways that exist in the subsurface, which have the potential to provide high efficiency recharge to the water table. This paper emphasizes the utility of creating data dense fine resolution geostatistical models and generating many realizations of the subsurface, which can then be used for analysis to understand the variability in recharge potential for specific recharge sites. These geostatistical realizations were investigated using connectivity metrics to evaluate the spread of highly conductive pathways throughout the subsurface. Connectivity analyses of high conductivity pathways show confidence that the study site- three vineyards located in the floodplain between the Cosumnes River and Deer Creek in Elk Grove, CA - has the potential to provide efficient recharge to the water table. These connectivity analyses can be completed prior to running computationally expensive and time intensive groundwater models and can be used as a way to understand variance between realizations of these geostatistical models.
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Ouyang, Ying, Prem B. Parajuli, and Daniel A. Marion. "Estimation of surface water quality in a Yazoo River tributary using the duration curve and recurrence interval approach." Water Supply 13, no. 2 (March 1, 2013): 515–23. http://dx.doi.org/10.2166/ws.2013.055.
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Pollution of surface water with harmful chemicals and eutrophication of rivers and lakes with excess nutrients are serious environmental concerns. This study estimated surface water quality in a stream within the Yazoo River Basin (YRB), Mississippi, USA, using the duration curve and recurrence interval analysis techniques. Data from the US Geological Survey (USGS) surface water monitoring station located in Deer Creek east of Leland from the YRB were selected for the analysis. Results showed that the water quality constituents, namely water temperature, specific conductivity (SC) and dissolved oxygen (DO), in this stream were found not to be the major concerns as the percentages of the time when these constituents did not meet their criteria were very low. Our results further revealed that the water temperature and SC increased as time elapsed, indicating the potential global warming and contamination impacts in this stream. In contrast, the DO and pH decreased as time elapsed, postulating a potential increase in biochemical oxygen demand and an acidic trend in this stream. Over the last decade, the average recurrence intervals when the water temperature, SC, and DO did not meet their criteria or minimum conditions were around 1 year. Using a target DO value of 429 kg d−1 proposed by the Mississippi Department of Environmental Quality, results from this study showed that there was about 25% of the time when the DO load did not meet the target value. This study suggests that the duration curve and recurrence interval analysis techniques are useful statistical tools for water quality trend estimation.
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NEWMAN, R. E., S. J. McCONNELL, R. H. WESTON, M. REEVES, C. BERNASCONI, P. J. BAKER, and P. C. WYNN. "The relationship between plasma testosterone concentrations and the seasonal variation in voluntary feed intake in fallow bucks (Dama dama)." Journal of Agricultural Science 130, no. 3 (May 1998): 357–66. http://dx.doi.org/10.1017/s0021859698005279.
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In two experiments conducted at Badgery's Creek, NSW (Latitude 34°S) the roles of testosterone and the thyroid hormones triiodothyronine (T3) and thyroxine (T4) as possible initiators of the change in voluntary feed intake (VFI) associated with the seasonal reproductive behaviour (rut) in male fallow deer were investigated.In Expt 1, the association between changes in these hormones with the onset of the rut was assessed in deer in which the timing of this event was manipulated by changing the photoperiod, or by melatonin administration. Groups were maintained under either natural photoperiod (n=6; control), a constant long daylength (16 h light[ratio ]8 h dark; n=9; LD group) or a constant long daylength and implanted with melatonin capsules (n=5; LD+M group) for 7 months from December until the following July. Blood samples were obtained weekly and VFI recorded.Feed intake decreased by 94% from the last week of March for 3 weeks in the control group. Changes of a similar magnitude were measured in the LD and LD+M groups but these changes were advanced by 1 and 9 weeks respectively in these groups. In all groups, circulating testosterone concentrations increased markedly at a time corresponding with the decrease in VFI. The concentrations returned to basal levels with the resumption in VFI. A distinct decrease in plasma concentrations of T3 and T4 in all three groups was associated with the decrease in VFI, however, the relationship with T3 was less apparent.In Expt 2, the role of testosterone in the regulation of the decline in VFI was investigated. Fallow bucks were treated with testosterone enanthate every 4 or 5 days for 28 days up to 6 weeks prior to the expected onset of the rut. Plasma testosterone concentrations, which were increased 13-fold, resulted in a decline in VFI which was comparable to that observed in the subsequent rut. Plasma free fatty acid concentrations were correlated negatively with the decline in VFI.Thus, the seasonal increase in circulating testosterone concentrations plays an important role in initiating the fall in VFI associated with the rut. As the rut was still apparent in animals maintained under an extended photoperiod, it is possible that factors other than decreasing daylength act as the cue for the timing of the rut.
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Srivastava, Anurag, Joan Q. Wu, William J. Elliot, Erin S. Brooks, and Dennis C. Flanagan. "A Simulation Study to Estimate Effects of Wildfire and Forest Management on Hydrology and Sediment in a Forested Watershed, Northwestern U.S." Transactions of the ASABE 61, no. 5 (2018): 1579–601. http://dx.doi.org/10.13031/trans.12326.
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Abstract. Suitable fuel reduction treatments are needed in the Colville National Forest, Washington, to reduce the risk of severe wildfire. This study aimed to identify high-risk erosion hillslopes following wildfire to aid in forest fuel reduction planning and to evaluate the effects of fuel treatments on the watershed hydrological response. The specific objectives were (1) to assess the soil burn severity associated with wildfires and use that information to identify critical hillslopes for forest fuel treatments, and (2) to evaluate the potential changes in water yield and peak flows from pre-treatment (undisturbed forest) to post-treatment (thinning and prescribed burn) conditions, in the East Deer Creek Watershed (EDCW), a subwatershed of the Colville National Forest. Assessments were made using a modeling approach for hypothetical wildfire and fuel treatment scenarios. FlamMap, a fire behavior model, was used to predict the spatial distribution of wildfire intensity for a hypothetical event under current vegetation conditions. WEPP simulations were subsequently completed to obtain sediment and water yields based on fire intensity and topography. WEPP erosion estimations following a simulated wildfire showed hillslope sediment yield varying from 0 to 49.4 Mg ha-1 year-1 from the 777 hillslopes, which were ranked in descending order of sediment yield to identify critical hillslopes for fuel treatments. The WEPP model calibrated for a nearby gauged watershed was then applied to the EDCW for pre-treatment and post-treatment conditions. At the watershed scale, the increase in water yield from pre-treatment to post-treatment conditions ranged from 0.7% to 5.6% on hillslopes delivering 10% to 50% of the predicted post-fire sediment. Simulated water balance components at the treated hillslopes showed substantial changes. Surface runoff, subsurface lateral flow, and deep percolation increased 150% (5 mm), 50% (9 mm), and 40% (41 mm), respectively, whereas evapotranspiration (ET) decreased 23% (124 mm). The relative differences between pre- and post-harvest peak flows showed no clear trends as treatment area increased. The results suggest that thinning and prescribed burns to treated hillslopes in the EDCW may lead to an increase in water yield and significant alterations in hydrological processes. Keywords: Fuel treatments, Modeling, Peak flows, Sediment, Water yield, Wildfire.
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Ufnar, Jennifer A., David F. Ufnar, Shiao Y. Wang, and R. D. Ellender. "Development of a Swine-Specific Fecal Pollution Marker Based on Host Differences in Methanogen mcrA Genes." Applied and Environmental Microbiology 73, no. 16 (June 22, 2007): 5209–17. http://dx.doi.org/10.1128/aem.00319-07.
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ABSTRACT The goal of this study was to evaluate methanogen diversity in animal hosts to develop a swine-specific archaeal molecular marker for fecal source tracking in surface waters. Phylogenetic analysis of swine mcrA sequences compared to mcrA sequences from the feces of five animals (cow, deer, sheep, horse, and chicken) and sewage showed four distinct swine clusters, with three swine-specific clades. From this analysis, six sequences were chosen for molecular marker development and initial testing. Only one mcrA sequence (P23-2) showed specificity for swine and therefore was used for environmental testing. PCR primers for the P23-2 clone mcrA sequence were developed and evaluated for swine specificity. The P23-2 primers amplified products in P23-2 plasmid DNA (100%), pig feces (84%), and swine waste lagoon surface water samples (100%) but did not amplify a product in 47 bacterial and archaeal stock cultures and 477 environmental bacterial isolates and sewage and water samples from a bovine waste lagoon and a polluted creek. Amplification was observed in only one sheep sample out of 260 human and nonswine animal fecal samples. Sequencing of PCR products from pig feces demonstrated 100% similarity to pig mcrA sequence from clone P23-2. The minimal amount of DNA required for the detection was 1 pg for P23-2 plasmid, 1 ng for pig feces, 50 ng for swine waste lagoon surface water, 1 ng for sow waste influent, and 10 ng for lagoon sludge samples. Lower detection limits of 10−6 g of wet pig feces in 500 ml of phosphate-buffered saline and 10−4 g of lagoon waste in estuarine water were established for the P23-2 marker. This study was the first to utilize methanogens for the development of a swine-specific fecal contamination marker.
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Floate, Kevin D. "Extent and patterns of hybridization among the three species of Populus that constitute the riparian forest of southern Alberta, Canada." Canadian Journal of Botany 82, no. 2 (February 1, 2004): 253–64. http://dx.doi.org/10.1139/b03-135.
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Three species of Populus (Salicaceae) overlap and hybridize in southern Alberta, Canada. Variation in leaf morphology throughout the region identifies five genetically distinct zones. The drainage of the Oldman River contains a pure zone of balsam poplar (Populus balsamifera L.), a pure zone of plains cottonwood (Populus deltoides Marsh.), plus overlap and hybrid zones of balsam poplar narrowleaf cottonwood (Populus angustifolia James) and balsam poplar narrowleaf cottonwood plains cottonwood. The drainage of the Red Deer River contains a pure zone of balsam poplar, a pure zone of plains cottonwood, plus an overlap and hybrid zone of balsam poplar plains cottonwood. Zones on both drainages coincide with an elevational gradient. Overlap and hybrid zones extend at least 700 river km (the length obtained by measuring distances between sites of hybridization on a river and its tributaries) combined across the two drainages. Principal components analyses on leaf morphology identify a pattern of bidirectional intro gression between sect. Tacamahaca (balsam poplar, narrowleaf cottonwood) species. These analyses also identify a pattern of unidirectional introgression between Tacamahaca and sect. Aigeiros (plains cottonwood) species, with F1 hybrids backcrossing only with the Tacamahaca parent. This pattern of unidirectional introgression subsequently was assessed and supported with data from the drainages of Ashley Creek and the Ogden River, Utah, which contain hybrid and overlap zones between narrowleaf cottonwood (Tacamahaca) and Fremont cottonwood, Populus fremontii S. Watson (Aigeiros). Given its unique nature in terms of extent, health, and composition, and given the effect of plant hybrid zones on the ecology and evolution of their associated organisms, it is hoped that the current study will facilitate future research targeting conservation of this riparian forest in its full genetic complexity.Key words: Populus, hybridization, riparian, cottonwood, introgression.
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Kuijper, Marijn, and Perry de Louw. "Brackish water ecosystem restoration based on integrated water system design." Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation 38, no. 1 (January 1, 2007): 115–25. http://dx.doi.org/10.2478/v10060-008-0028-z.
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Brackish water ecosystem restoration based on integrated water system design Despite their current location within a primary agricultural area, most of the creek remnants in the Dutch clay polder areas have a high potential for recovery into healthy ecosystems. Like most areas in the Netherlands the clay polders are densely populated. Therefore multifunctional land use is encouraged and different types of land use coexist within small distances from each other. As a result water conflicts occur: agricultural land use requires deep groundwater levels and causes eutrophication by spreading nutrients into the water system, while existing ecosystems within and around the creek remnants need wetland conditions and low nutrient levels. Furthermore periods of high discharge cause flooding of arable land. Extreme measures like filling in ditches and increasing water levels are needed to achieve the water targets for wetlands around the creeks. On the other hand, the effects of these measures easily cause water logging in nearby agricultural areas. We introduce an integrated approach for the restoration of creek ecosystems. Both the complex interaction of groundwater, surface water and ecology and the limiting conditions imposed by adjacent agricultural land use, spatial developments and regulatory settings like the European Water Framework Directive are thereby taken into account. A highly integrated set of measures is proposed creating optimal conditions for both high agricultural production and flourishing creek ecosystems.
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Hansen, Carly, and Gustavious Williams. "Evaluating Remote Sensing Model Specification Methods for Estimating Water Quality in Optically Diverse Lakes throughout the Growing Season." Hydrology 5, no. 4 (November 14, 2018): 62. http://dx.doi.org/10.3390/hydrology5040062.
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Spectral images from remote sensing platforms are extensively used to estimate chlorophyll-a (chl-a) concentrations for water quality studies. Empirical models used for estimation are often based on physical principles related to light absorption and emission properties of chl-a and generally relying on spectral bands in the green, blue, and near-infrared bands. Because the physical characteristics, constituents, and algae populations vary widely from lake to lake, it can be difficult to estimate coefficients for these models. Many studies select a model form that is a function of these bands, determine model coefficients by correlating remotely-measured surface reflectance data and coincidentally measured in-situ chl-a concentrations, and then apply the model to estimate chl-a concentrations for the entire water body. Recent work has demonstrated an alternative approach using simple statistical learning methods (Multiple Linear Stepwise Regression (MLSR)) which uses historical, non-coincident field data to develop sub-seasonal remote sensing chl-a models. We extend this previous work by comparing this method against models from literature, and explore model performance for a region of lakes in Central Utah with varying optical complexity, including two relatively clear intermountain reservoirs (Deer Creek and Jordanelle) and a highly turbid, shallow lake (Utah Lake). This study evaluates the suitability of these different methods for model parameterization for this area and whether a sub-seasonal approach improves performance of standard model forms from literature. We found that while some of the common spectral bands used in literature are selected by the data-driven MLSR method for the lakes in the study region, there are also other spectral bands and band interactions that are often more significant for these lakes. Comparison of model fit shows an improvement in model fit using the data-driven parameterization method over the more traditional physics-based modeling approaches from literature. This suggests that the sub-seasonal approach and exploitation of information contained in other bands helps account for lake-specific optical characteristics, such as suspended solids and other constituents contributing to water color, as well as unique (and season-specific) algae populations, which contribute to the spectral signature of the lake surface, rather than only relying on a generalized optical signature of chl-a. Consideration of these other bands is important for development of models for long-term and entire growing season applications in optically diverse water bodies.
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Clausen, Eric. "Using topographic map interpretation methods to determine Tookany (Tacony) Creek erosion history upstream from Philadelphia, Pennsylvania, USA." Journal of Geography and Geology 8, no. 4 (December 2, 2016): 30. http://dx.doi.org/10.5539/jgg.v8n4p30.
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Topographic map interpretation methods are used to determine erosional landform origins in and adjacent to the Tookany (Tacony) Creek drainage basin, located upstream from and adjacent to Philadelphia, PA. Five wind gaps notched into the Tookany-Wissahickon Creek drainage divide (which is also the Delaware-Schuylkill River drainage divide), a deep through valley crossing the Tookany-Pennypack Creek drainage divide, a Tookany Creek elbow of capture, orientations of Tookany Creek tributary valleys, a narrow valley carved in erosion resistant metamorphic bedrock, and the relationship of a major Tookany Creek direction change with a Pennypack Creek elbow of capture and a Pennypack Creek barbed tributary are used along with other evidence to reconstruct how a deep south oriented Tookany Creek valley eroded headward across massive southwest oriented flood flow. The flood flow origin cannot be determined from Tookany Creek drainage basin evidence, but may have been derived from a melting continental ice sheet, and originally flowed across the Tookany Creek drainage basin region on a low gradient topographic surface equivalent in elevation to or higher than the highest present day Tookany Creek drainage divide elevations with the water flowing in a complex of shallow diverging and converging channels that had formed by scouring of less resistant bedrock units and zones. William Morris Davis, sometimes referred to as the father of North American geomorphology, spent much of his boyhood and several years as a young man living in the Tookany Creek drainage basin and all landforms discussed here were within walking distance of his home and can be identified on a topographic map published while he was developing and promoting his erosion cycle ideas. Davis never published about Tookany Creek drainage basin erosion history, but he developed and promoted uniformitarian and erosion cycle models that failed to recognize the significance of Tookany Creek drainage basin erosional landform features providing evidence of the immense floods that once crossed present day drainage divides and eroded the Tookany Creek drainage basin.
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Lu, H. Y. "Characterization of extractable metals from the aquifers with arsenic contamination in the Tsengwen Creek, Taiwan." Soil and Water Research 9, No. 2 (April 25, 2014): 66–76. http://dx.doi.org/10.17221/42/2013-swr.
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Arsenic contamination in groundwater is a common groundwater problem worldwide. To manage groundwater resources effectively, it is crucial to determine the arsenic source. Taiwan’s Tsengwen Creek watershed is one of the known areas for groundwater arsenic contamination. Water-rock interactions are evaluated on a regional scale. A conceptual hydrogeological framework is first established based on groundwater hydrochemistry. The local aquifer system can be categorized into high-arsenic deep aquifer and low-arsenic shallow aquifer. The average geochemistry of sediments indicates that arsenic and heavy metals are not significantly enriched in the deeper aquifer on the scale of the whole watershed. Therefore, arsenic contamination in the deeper groundwater of the Tsengwen Creek watershed is not simply source-controlled. However, the Fe-Mn oxides in sediments contain slightly more arsenic in the deep aquifer. The long residence time of groundwater could magnify the enrichment and cause natural arsenic contamination in the deep aquifer.
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Lukas, Robert, and Konrad F. Weidich. "New Results of the Mid-Cretaceous of the Schleifmühl Creek and Hammer Creek ("Hell" area, E Füssen/Allgäu)." Zeitschrift der Deutschen Geologischen Gesellschaft 138, no. 1 (January 1, 1987): 77–101. http://dx.doi.org/10.1127/zdgg/138/1987/77.
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Clausen, Eric. "Geomorphic History of the Beaver Creek Drainage Basin as Determined from Topographic Map Evidence: Eastern Montana and Western North Dakota, USA." Journal of Geography and Geology 10, no. 3 (August 28, 2018): 79. http://dx.doi.org/10.5539/jgg.v10n3p79.
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The Beaver Creek drainage basin is located along the North Dakota-Montana border slightly to the south of a recognized continental ice sheet margin and immediately to the east of the deep northeast-oriented Yellowstone River valley with Beaver Creek flowing in a north and northeast direction to join the north-oriented Little Missouri River. The Beaver Creek drainage basin originates on an escarpment-surrounded upland and its erosional history was determined by analyzing detailed topographic maps aided by previously made field observations that showed coarse-grained and distinctive alluvium had been transported in an east direction across the Beaver Creek drainage basin and across what is now the deep Little Missouri River valley to sediments making up southwest North Dakota high points containing both the distinctive alluvium and Oligocene age fossils. Drainage divides surrounding the Beaver Creek drainage basin show numerous divide crossings (or notches) linking northwest-oriented Yellowstone River tributary valleys with east-oriented Beaver Creek tributary valleys and west- or northwest-oriented Beaver Creek tributary valleys with southeast- or east-oriented Little Missouri River tributary valleys and suggest the Beaver Creek valley eroded headward across a large-scale flood formed anastomosing channel complex. Buttes located just to the east of the Beaver Creek-Little Missouri River drainage divide suggest the east-oriented water removed as much as 150 meters, or more, of Beaver Creek drainage basin bedrock, and even greater amounts of bedrock from regions to the south of the Beaver Creek drainage basin. Topographic map evidence and routes traveled by the distinctive alluvium suggest a continental ice sheet blocked a large and high-level northeast-oriented river and diverted at least some of the water along the ice sheet margin with the east-oriented floodwaters being captured in a progressive sequence by headward erosion of the Little Missouri River, Beaver Creek, and Yellowstone River valleys (in that order).
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Huntley, David H., and Bruce E. Broster. "Glacial Lake Camelsfoot: a Late Wisconsinan advance stage proglacial lake in the Fraser River valley, Gang Ranch area, British Columbia." Canadian Journal of Earth Sciences 31, no. 5 (May 1, 1994): 798–807. http://dx.doi.org/10.1139/e94-073.
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In the Gang Ranch area, British Columbia, interaction between the regional physiography and ice flow during the Late Wisconsinan Fraser Glaciation resulted in the formation of a proglacial lake confined to valleys of the Fraser River and its tributaries. Lithostratigraphic and geomorphic evidence suggests that ponding was initiated in the Big Bar Creek area where the Fraser River is confined to a deep canyon in the Camelsfoot Range. During ice advance, a proglacial lake system developed that progressively deepened and reached a minimum upper elevation of approximately 710 m asl prior to being overridden by ice. We propose that this system be formally named "Glacial Lake Camelsfoot." A composite stratotype, comprising lithostratigraphic units associated with Glacial Lake Camelsfoot, is described from eight reference sections along Fraser River, Churn, and Lone Cabin creeks in the Gang Ranch area. Additional geomorphic evidence indicates that at the Fraser Glaciation maximum, the Cordilleran Ice Sheet in the study area ranged from 600 to 2000 m in thickness.
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Wang, Yan Chun, Yuan Li, and Jian Guang Li. "Numerical Analysis for Thermal-Chemical-Stress Coupling in Deep Rock Creep Properties." Key Engineering Materials 561 (July 2013): 657–62. http://dx.doi.org/10.4028/www.scientific.net/kem.561.657.
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The control equations for analyzing coupled thermal chemical-mechanical phenomena of deep rocks are established. Using creep equation by experimental data, 3D numerical simulation for creep properties of deep soft tunnel under coupling effect of temperature field, chemical field and stress field are conducted by ANSYS, and different effects of these fields on deep soft rock tunnel creep properties are analyzed, whats more time-creep curves of different temperature, pH value and stress deviation of the mid-point of the top of tunnel are obtained. Effect of these three fields on creep characteristics of deep soft rock cant be ignored. Under deep complex environment, high-stress is main factor of tunnel creep; creep increasing with temperature increasing. From simulation results, we get whether acidic environment or alkaline environment causes significantly stronger corrosive effect on the rock mass than the neutral environment, and increases its creep.
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Wang, Yanchun, Yongyan Wang, Chuanqi Su, and Jianguang Li. "Study of Influence of Environmental Factors on Deep Shale Creep Properties." Shock and Vibration 2018 (November 15, 2018): 1–8. http://dx.doi.org/10.1155/2018/9165238.
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In order to study the influence of environmental factors on creep properties of deep shale, a series of creep tests of deep black shales are performed under different environmental conditions, including stress deviation, temperature, and chemical pH value. The influence of these conditions on creep properties of deep shale is studied. The results show that the creep and creep rate of shale will grow with the increase of temperature, stress difference, and acidity-alkalinity. We get nonlinear creep model of deep shale when pH = 4 and T = 30°C. The critical stress difference of deep shale is no larger than 31.04 MPa when the chemical pH value is 4 and the temperature is 30°C. By scanning shale after corrosion, we know that the effects of chemical pH value on the creep characteristics are mainly determined by the feldspar dissolution and corrosion caused by chemical action. Our work has important theoretical significance and practical value for evaluating rock engineering stability.
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Foriero, A., B. Ladanyi, S. R. Dallimore, P. A. Egginton, and F. M. Nixon. "Modelling of deep seated hill slope creep in permafrost." Canadian Geotechnical Journal 35, no. 4 (August 1, 1998): 560–78. http://dx.doi.org/10.1139/t98-024.
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Attempts have been made to simulate hillslope creep observations at a site near the village of Tuktoyaktuk, Northwest Territories. Unlike other creep studies in permafrost, this site was unique in that the deformations occurred within a massive ice body, forming the core of a 30 m high concentric hill approximately 1200 m long and 700 m wide. The described simulation model of slope creep is based on both an extension of a closed-form solution originally proposed for two- and three-dimensional ice caps and a finite element creep analysis. The solution covers cyclic temperature fluctuations and incorporates spatial variations of the temperature-dependent creep parameters. Results of simulations are compared with in situ measurements of creep displacements in the hill.Key words: permafrost, slope, creep, in situ measurements, numerical simulation.
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Clausen, Eric. "Pennypack Creek Drainage Basin Erosion History: Bucks, Montgomery, and Philadelphia Counties, PA, USA." Journal of Geography and Geology 9, no. 1 (February 27, 2017): 37. http://dx.doi.org/10.5539/jgg.v9n1p37.
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Topographic map evidence is used to interpret Pennypack Creek drainage basin erosion history in and north of the City of Philadelphia, Pennsylvania (USA). Southwest and west-southwest oriented through valleys crossing the south oriented Pennypack Creek drainage basin, barbed Pennypack Creek tributaries, and significant valley direction changes are used to determine that the Pennypack Creek valley eroded headward across massive southwest oriented floods. Initially floodwaters flowed on a low gradient topographic surface at least as high, if not higher, than the highest Pennypack Creek drainage basin elevations today. Shallow low gradient diverging and converging flow channels were eroded into the underlying bedrock surface predominantly along fault lines and other zones of easier to erode materials. Headward erosion of the much deeper Pennypack Creek valley across this anastomosing channel complex captured southwest oriented floodwaters and flow on northeast ends of beheaded channels was reversed so as to move toward the newly eroded and deeper Pennypack Creek valley. These reversed flow channels captured southwest oriented floodwaters still moving north of the actively eroding Pennypack Creek valley head. This captured water then moved in a northeast direction and eroded deep northeast oriented valleys headward from the newly eroded Pennypack Creek valley. These valleys today account for northeast and east oriented Pennypack Creek valley segments and northeast oriented (barbed) tributaries flowing to south oriented Pennypack Creek. The floodwater source cannot be determined from Pennypack Creek drainage basin evidence, but was from the northeast. Melting of a continental ice sheet could produce floods of sufficient volume and duration to overwhelm whatever drainage system previously existed and to erode new drainage basins in a manner similar to how the Pennypack Creek drainage basin was eroded.
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Lin, Bin, Zhi Bo Chen, and Tao Ma. "The Test Study of Genetic Creep Kernel Function of Artificial Frozen Clay and its Parameters." Advanced Materials Research 368-373 (October 2011): 2634–37. http://dx.doi.org/10.4028/www.scientific.net/amr.368-373.2634.
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The test study the creep property of artificial frozen clay at different frozen temperature by independently developed uniaxial creep testing machine WDT-100, the test result indicated that the nonlinear creep property of deep artificial frozen clay can be described by the function as ε=atb. It is found that the creep of deep frozen clay can be calculated by genetic theory through contrastive study, analysis of parameters of genetic creep kernel function shows that the parameter a and creep stress are exponential relationship while linear correlation with test temperature, parameter b is only related to creep stress.
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Afzaal, Hassan, Aitazaz A. Farooque, Farhat Abbas, Bishnu Acharya, and Travis Esau. "Groundwater Estimation from Major Physical Hydrology Components Using Artificial Neural Networks and Deep Learning." Water 12, no. 1 (December 18, 2019): 5. http://dx.doi.org/10.3390/w12010005.
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Precise estimation of physical hydrology components including groundwater levels (GWLs) is a challenging task, especially in relatively non-contiguous watersheds. This study estimates GWLs with deep learning and artificial neural networks (ANNs), namely a multilayer perceptron (MLP), long short term memory (LSTM), and a convolutional neural network (CNN) with four different input variable combinations for two watersheds (Baltic River and Long Creek) in Prince Edward Island, Canada. Variables including stream level, stream flow, precipitation, relative humidity, mean temperature, evapotranspiration, heat degree days, dew point temperature, and evapotranspiration for the 2011–2017 period were used as input variables. Using a hit and trial approach and various hyperparameters, all ANNs were trained from scratched (2011–2015) and validated (2016–2017). The stream level was the major contributor to GWL fluctuation for the Baltic River and Long Creek watersheds (R2 = 50.8 and 49.1%, respectively). The MLP performed better in validation for Baltic River and Long Creek watersheds (RMSE = 0.471 and 1.15, respectively). Increased number of variables from 1 to 4 improved the RMSE for the Baltic River watershed by 11% and for the Long Creek watershed by 1.6%. The deep learning techniques introduced in this study to estimate GWL fluctuations are convenient and accurate as compared to collection of periodic dips based on the groundwater monitoring wells for groundwater inventory control and management.
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Li, Xiaofeng, and Zhixiang Yin. "Analysis of Shear Characteristics of Deep, Anchored Rock Mass under Creep Fatigue Loading." Advances in Civil Engineering 2021 (August 18, 2021): 1–13. http://dx.doi.org/10.1155/2021/2326237.
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To study the influence of earthquakes and engineering disturbances on the deformation of deeply buried rock masses, shear tests were carried out on anchored sandstone rock masses, anchored marble rock masses, and anchored granite rock masses under creep fatigue loading, and a new creep fatigue model was established to characterize the deformation characteristics of anchored rock masses under creep fatigue loading. The creep fatigue curves of different lithologies clearly show three stages: creep attenuation, steady-state creep, and accelerated creep. Fatigue loading can increase the creep of anchored specimens, and the lower the rock strength is, the higher the creep variable under fatigue loading is. However, for the same rock strength, with the increase in load level, the creep variable produced by creep fatigue load presents a linear downward trend. Considering the changes in the mechanical properties of the anchored rock mass under creep fatigue loading, the creep fatigue model of anchored rock masses is established by introducing a function of the fatigue shear modulus, and the accuracy and applicability of the model are verified by laboratory creep fatigue test data. The model provides a theoretical basis for the study of anchored rock mass support under low-frequency earthquakes or blasting loads.
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Wang, Yan Chun, and Yong Yan Wang. "Study on Nonlinear Viscoelasto-Plastic Creep Model of Deep Soft Rock." Advanced Materials Research 430-432 (January 2012): 168–72. http://dx.doi.org/10.4028/www.scientific.net/amr.430-432.168.
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Based on the mechanical behaviors of deep soft rock at the accelerating creep stage, a nonlinear rheological cell containing exponential equation replaces classic linear cell, a new nonlinear viscoelasto-plastic creep model of deep soft rock is established on the basis of Nishihara model, and the model can describe the three stages of rock nonlinear creep. Using the least squares method of Matlab to investigate test results, the result shows the new nonlinear creep model accords better with the creep test curves, and verify correctness of the new model.
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Wang, Chun Qiu, Shi Bin Gu, Zhong Ju Wei, Bo Li, and Shao Jie Chen. "DYNA Numerical Experiment on Long-Term Stability of Strip Pillar in Deep Mine." Advanced Materials Research 217-218 (March 2011): 1520–24. http://dx.doi.org/10.4028/www.scientific.net/amr.217-218.1520.
Full textAbstract:
The creep test of the No. 3 coal seam of Daizhuang Coal Mine is carried. Based on the experiment results, the creep support effect of deep pillar is analyzed with LS-DYNA. The results show that the circumferential initial creep stress of the tested coal is 3.061MPa and the circumferential initial creep stress is far below the axial initial creep stress which is 7.020MPa. In addition, the creep strength is 9.3266MPa and the creep coefficient is 0.6472. According to the test results, the creep support effect of deep strip pillar can be simulated excellently with LS-DYNA. Stress and deformation in simulated strip pillar show evident rheology. Many changes will take place in the stable situation of pillar after the working face mining. Under the effect of the overlying strata, this pillar turns into steady creep state after 15~16 months, then the pillar is able to maintain long-term stable state.
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Leggott, Mark, and Gordon Pritchard. "The effect of temperature on rate of egg and larval development in populations of Argia vivida Hagen (Odonata: Coenagrionidae) from habitats with different thermal regimes." Canadian Journal of Zoology 63, no. 11 (November 1, 1985): 2578–82. http://dx.doi.org/10.1139/z85-384.
Full textAbstract:
The hypothesis was tested that isolated populations of Argia vivida living in habitats with different thermal regimes would show similar rates of egg and larval development when reared at any constant temperature. Eggs from three populations developed and hatched normally over the temperature range 12.5–32.5 °C, but development rates at 15 and 20 °C were faster in a population from a habitat with daily and annual fluctuations in temperature (Deep Creek, Idaho) than in a population from a more stable geothermal regime (Banff, Alberta), which were in turn faster than in a population from a geothermal site with damped annual fluctuations (Albert Canyon, British Columbia). However, differences between slope or intercept values for the regressions of development time on temperature from the three sites were not statistically significant. Growth rates for Deep Creek larvae were also generally higher than for Banff larvae at all temperatures in all instars, but few of these differences were statistically significant. An estimate of 2600 degree-days above 11.25 °C for completion of egg and larval development leads to prediction of a 1-year life cycle at Banff, a 2- or 3-year life cycle at Deep Creek, and a 3-year life cycle at Albert Canyon.