A Late Cretaceous Microfossil Assemblage from the Buffalo Head Hills, North-Central Alberta

1975 ◽  
Vol 12 (7) ◽  
pp. 1157-1174 ◽  
Author(s):  
John H. Wall ◽  
Chaitanya Singh
Keyword(s):  
The Arctic ◽  
Pollen Assemblage ◽  
North Central ◽  
Radiolarian Assemblage ◽  
Southern Alberta ◽  
Corroborative Evidence ◽  
Northern Alaska ◽  
Microfossil Assemblage ◽  
Northern Alberta ◽  
Upper Campanian

A small outcrop belonging to an unnamed shale unit in the Buffalo Head Hills of north-central Alberta has yielded marine microfossils of Senonian, most probably Campanian, age.The foraminiferal fauna, including Haplophragmoides fraseri, Verneuilinoides bearpawensis, Praebulimina carseyae and Cassidella tegulata, suggests equivalence with that of the upper Campanian Bearpaw fauna of southern Alberta.The radiolarian assemblage includes Spongurus (Spongurantha) sp., Spongodiscus (Spongodisus) sp. cf. S. (S.) renillaeformis, Spongostaurus sp., Spongotripus (Spongotripus) sp. cf. S. (S.) morenoensis and Dictyomitra (Dictyomitra) multicostata, which are present in the Bearpaw Formation of southern Alberta, and in an interval of the Schrader Bluff Formation of northern Alaska, considered middle Senonian in age.Among the dinoflagellates recorded from the outcrop, three species of Dinogymnium – D. acuminatum, D. longicornis and D. sibiricum, and four species of Deflandrea – D. granulifera, D. minor, D. spectabilis and D. victoriensis are restricted to strata of Senonian age (inclusive of Maestrichtian Stage). Of this group, Dinogymnium longicornis, Deflandrea granulifera and D. spectabilis are present in the Bearpaw Formation of southern Alberta. The dinoflagellate assemblage has four species in common with that of the Senonian or younger beds in western Siberia.The pollen assemblage is dominated by species of Aquilapollenites – A. dolium, A. trialatus and A. turbidus – strongly indicative of a Campanian age. A megaspore, Balmeisporites rarus, suggests a Senonian age.The microfossil assemblage provides corroborative evidence in support of J. A. Jeletzky's hypothesis that a marine connection existed between the Arctic and Western Interior regions through northern Alberta during the Santonian and Campanian.

Danian Mollusks from the Prince Creek Formation, Northern Alaska, and Implications for Arctic Ocean Paleogeography

1993 ◽  
Vol 67 (S35) ◽  
pp. 1-35 ◽  
Author(s):  
Louie Marincovich
Keyword(s):  
Arctic Ocean ◽  
World Ocean ◽  
Ocean Basin ◽  
The Arctic ◽  
The North ◽  
The World ◽  
The Arctic Ocean ◽  
Molluscan Fauna ◽  
Endemic Genera ◽  
Northern Alaska

The marine molluscan fauna of the Prince Creek Formation near Ocean Point, northern Alaska, is of Danian age. It is the only diverse and abundant Danian molluscan fauna known from the Arctic Ocean realm, and is the first evidence for an indigenous Paleocene shallow-water biota within a discrete Arctic Ocean Basin faunal province.A high percentage of endemic species, and two endemic genera, emphasize the degree to which the Arctic Ocean was geographically isolated from the world ocean during the earliest Tertiary. Many of the well-preserved Ocean Point mollusks, however, also occur in Danian faunas of the North American Western Interior, the Canadian Arctic Islands, Svalbard, and northwestern Europe, and are the basis for relating this Arctic Ocean fauna to that of the Danian world ocean.The Arctic Ocean was a Danian refugium for some genera that became extinct elsewhere during the Jurassic and Cretaceous. At the same time, this nearly landlocked ocean fostered the evolution of new taxa that later in the Paleogene migrated into the world ocean by way of the northeastern Atlantic. The first Cenozoic occurrences are reported for the bivalves Integricardium (Integricardium), Oxytoma (Hypoxytoma), Placunopsis, Tancredia (Tancredia), and Tellinimera, and the oldest Cenozoic records given for the bivalves Gari (Garum), Neilo, and Yoldia (Cnesterium). Among the 25 species in the molluscan fauna are four new gastropod species, Amauropsis fetteri, Ellipsoscapha sohli, Mathilda (Fimbriatella) amundseni, and Polinices (Euspira) repenningi, two new bivalve genera, Arcticlam and Mytilon, and 15 new bivalve species, Arcticlam nanseni, Corbula (Caryocorbula) betsyae, Crenella kannoi, Cyrtodaria katieae, Gari (Garum) brouwersae, Integricardium (Integricardium) keenae, Mytilon theresae, Neilo gryci, Nucula (Nucula) micheleae, Nuculana (Jupiteria) moriyai, Oxytoma (Hypoxytoma) hargrovei, Placunopsis rothi, Tancredia (Tancredia) slavichi, Tellinimera kauffmani, and Yoldia (Cnesterium) gladenkovi.

Expansion of the Trade in Northern Alaska and Western Arctic Canada

2018 ◽  
Author(s):  
John R. Bockstoce
Keyword(s):  
San Francisco ◽  
Fur Trade ◽  
The Arctic ◽  
Arctic Canada ◽  
Trading Company ◽  
Whaling Industry ◽  
Western Arctic ◽  
Northern Alaska

This chapter focuses on the development and advance of the arctic fur trade to the year 1914: the decline of the shore whaling industry and the rise of the market for white fox furs; the beginning of the dispersal of trapping families along the coast; the importance of the Cape Smythe Whaling and Trading Company at Barrow, Alaska; and the activities of H. Liebes and Company, furriers of San Francisco.

Escherichia coli O157:H7 Lineages in Healthy Beef and Dairy Cattle and Clinical Human Cases in Alberta, Canada

2009 ◽  
Vol 72 (3) ◽  
pp. 601-607 ◽  
Author(s):  
RANJANA SHARMA ◽  
KIM STANFORD ◽  
MARIE LOUIE ◽  
KRYSTY MUNNS ◽  
S. JACOB JOHN ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Tetracycline Resistance ◽  
Geographic Location ◽  
Feedlot Cattle ◽  
Pulsed Field Gel Electrophoresis ◽  
Escherichia Coli O157 ◽  
Strain Diversity ◽  
Significant Difference ◽  
Southern Alberta ◽  
Northern Alberta

The aim of this study was to examine the prevalence and distribution of Escherichia coli O157:H7 lineage-specific polymorphism assay (LSPA) 6 genotypes from cattle (n = 313) and clinical human (n = 203) isolates from northern and southern Alberta, Canada, to understand possible associations of genotypes with host and geographic location. The majority of cattle isolates (feedlot and dairy) typed as LSPA-6 111111 (72.2%), with proportionately higher LSPA-6 222222 (19.4%) than other LSPA-6 genotypes (10.7%). Clinical human isolates also typed primarily as LSPA-6 111111 (90.1%), but a higher percentage of genotypes (6.8%) other than LSPA-6 222222 (3.1%) was observed. A significantly higher frequency of LSPA-6 111111 in southern Alberta cattle (P < 0.0001) and a significant difference in LSPA-6 genotypes between human versus feedlot cattle from northern Alberta (P < 0.0001) were detected. LSPA-6 211111 genotype was third and second most common in cattle and humans, respectively, and several new LSPA-6 genotypes (n = 19) were also discovered. Despite avoiding over-representation of isolates from specific farms or outbreaks, higher strain diversity among cattle by pulsed-field gel electrophoresis (PFGE; 50 genotypes) in contrast to human (9 PFGE genotypes) isolates was observed. The majority of cattle (74.4%) and human (90.6%) isolates were susceptible to the antimicrobials tested. Within resistant cattle isolates, sulfisoxazole-tetracycline resistance was common (62.5%) and was accounted for by the presence of sul1 and sul2, and tet(A) and tet(B) determinants. An association between LSPA-6 and PFGE genotypes but not between geographic location and PFGE genotype for both hosts was evident.

scholarly journals Dynamical Downscaling Data for Studying Climatic Impacts on Hydrology, Permafrost, and Ecosystems in Arctic Alaska

2016 ◽  
Author(s):  
Lei Cai ◽  
Vladimir A. Alexeev ◽  
Christopher D. Arp ◽  
Benjamin M. Jones ◽  
Anna Liljedahl ◽  
...  
Keyword(s):  
Observational Data ◽  
Dynamical Downscaling ◽  
Dew Point ◽  
Climatic Variables ◽  
The Arctic ◽  
Linear Scaling ◽  
Permafrost Degradation ◽  
Near Surface ◽  
Temperature Bias ◽  
Northern Alaska

Abstract. Climatic changes are most pronounced in northern high latitude regions. Yet, there is a paucity of observational data, both spatially and temporally, such that regional-scale dynamics are not fully captured, limiting our ability to make reliable projections. In this study, a group of dynamical downscaling products were created for the period 1950 to 2100 to better understand climate change and its impacts on hydrology, permafrost, and ecosystems at a resolution suitable for northern Alaska. An ERA-interim reanalysis dataset and the Community Earth System Model (CESM) served as the forcing mechanisms in this dynamical downscaling framework, and the Weather Research & Forecast (WRF) model, embedded with an optimization for the Arctic (Polar WRF), served as the Regional Climate Model (RCM). This downscaled output consists of multiple climatic variables (precipitation, temperature, wind speed, dew point temperature, and surface air pressure) for a 10 km grid spacing at three-hour intervals. The modeling products were evaluated and calibrated using a bias-correction approach. The ERA-interim forced WRF (ERA-WRF) produced reasonable climatic variables as a result, yielding a more closely correlated temperature field than precipitation field when long-term monthly climatology was compared with its forcing and observational data. A linear scaling method then further corrected the bias, based on ERA-interim monthly climatology, and bias-corrected ERA-WRF fields were applied as a reference for calibration of both the historical and the projected CESM forced WRF (CESM-WRF) products. Biases, such as, a cold temperature bias during summer and a warm temperature bias during winter as well as a wet bias for annual precipitation that CESM holds over northern Alaska persisted in CESM-WRF runs. The linear scaling of CESM-WRF eventually produced high-resolution downscaling products for the Alaskan North Slope for hydrological and ecological research, together with the calibrated ERA-WRF run, and its capability extends far beyond that. Other climatic research has been proposed, including exploration of historical and projected climatic extreme events and their possible connections to low-frequency sea-atmospheric oscillations, as well as near-surface permafrost degradation and ice regime shifts of lakes. These dynamically downscaled, bias corrected climatic datasets provide improved spatial and temporal resolution data necessary for ongoing modeling efforts in northern Alaska focused on reconstructing and projecting hydrologic changes, ecosystem processes and responses, and permafrost thermal regimes. The dynamical downscaling methods presented in this study can also be used to create more suitable model input datasets for other sub-regions of the Arctic. Supplementary data are available at https://doi.org/10.1594/PANGAEA.863625.

scholarly journals Risks Without Borders: A Cultural Consensus Model of Risks to Sustainability in Rapidly Changing Social–Ecological Systems

2020 ◽  
Vol 12 (6) ◽  
pp. 2446 ◽  
Author(s):  
Berill Blair ◽  
Amy Lovecraft
Keyword(s):  
Environmental Changes ◽  
The Arctic ◽  
Cultural Consensus ◽  
Social Challenges ◽  
Consensus Analysis ◽  
Cultural Consensus Analysis ◽  
Social Ecological ◽  
Adaptation Action ◽  
Northern Alaska ◽  
Shared Understandings

Global sustainability goals cannot realistically be achieved without strategies that build on multiscale definitions of risks to wellbeing. Particularly in geographic contexts experiencing rapid and complex social and environmental changes, there is a growing need to empower communities to realize self-identified adaptation goals that address self-identified risks. Meeting this demand requires tools that can help assess shared understandings about the needs for, and barriers to, positive change. This study explores consensus about risks and uncertainties in adjacent boroughs grappling with rapid social–ecological transformations in northern Alaska. The Northwest Arctic and North Slope boroughs, like the rest of the Arctic, are coping with a climate that is warming twice as fast as in other regions. The boroughs are predominantly inhabited by Iñupiat people, for whom the region is ancestral grounds, whose livelihoods are still supported by subsistence activities, and whose traditional tribal governance has been weakened through multiple levels of governing bodies and institutions. Drawing on extensive workshop discussions and survey experiments conducted with residents of the two boroughs, we developed a model of the northern Alaska region’s social–ecological system and its drivers of change. Using cultural consensus analysis, we gauged the extent of consensus across the boroughs about what key risks threaten the sustainability of their communities. Though both boroughs occupy vast swaths of land, each with their own resource, leadership, and management challenges, we found strong consensus around how risks that impact the sustainability of communities are evaluated and prioritized. Our results further confirmed that rapid and complex changes are creating high levels of uncertainties for community planners in both boroughs. We discuss the mobilizing potential of risk consensus toward collective adaptation action in the civic process of policy making. We note the contribution of cultural consensus analysis as a tool for cross-scale learning in areas coping with rapid environmental changes and complex social challenges.

High-precision U–Pb CA–ID–TIMS dating and chronostratigraphy of the dinosaur-rich Horseshoe Canyon Formation (Upper Cretaceous, Campanian–Maastrichtian), Red Deer River valley, Alberta, Canada

2020 ◽  
Vol 57 (10) ◽  
pp. 1220-1237 ◽  
Author(s):  
David A. Eberth ◽  
Sandra L. Kamo
Keyword(s):  
High Precision ◽  
Coastal Plain ◽  
Upper Cretaceous ◽  
Red Deer ◽  
Alluvial Plain ◽  
Type Area ◽  
Southern Alberta ◽  
Dinosaur Evolution ◽  
Horseshoe Canyon Formation ◽  
Upper Campanian

The non-marine Horseshoe Canyon Formation (HCFm, southern Alberta) yields taxonomically diverse, late Campanian to middle Maastrichtian dinosaur assemblages that play a central role in documenting dinosaur evolution, paleoecology, and paleobiogeography leading up to the end-Cretaceous extinction. Here, we present high-precision U–Pb CA–ID–TIMS ages and the first calibrated chronostratigraphy for the HCFm using zircon grains from (1) four HCFm bentonites distributed through 129 m of section, (2) one bentonite from the underlying Bearpaw Formation, and (3) a bentonite from the overlying Battle Formation that we dated previously. In its type area, the HCFm ranges in age from 73.1–68.0 Ma. Significant paleoenvironmental and climatic changes are recorded in the formation, including (1) a transition from a warm-and-wet deltaic setting to a cooler, seasonally wet-dry coastal plain at 71.5 Ma, (2) maximum transgression of the Drumheller Marine Tongue at 70.896 ± 0.048 Ma, and (3) transition to a warm-wet alluvial plain at 69.6 Ma. The HCFm’s three mega-herbivore dinosaur assemblage zones track these changes and are calibrated as follows: Edmontosaurus regalis – Pachyrhinosaurus canadensis zone, 73.1–71.5 Ma; Hypacrosaurus altispinus – Saurolophus osborni zone, 71.5–69.6 Ma; and Eotriceratops xerinsularis zone, 69.6–68.2 Ma. The Albertosaurus Bonebed — a monodominant assemblage of tyrannosaurids in the Tolman Member — is assessed an age of 70.1 Ma. The unusual triceratopsin, Eotriceratops xerinsularis, from the Carbon Member, is assessed an age of 68.8 Ma. This chronostratigraphy is useful for refining correlations with dinosaur-bearing upper Campanian–middle Maastrichtian units in Alberta and elsewhere in North America.

The influence of chick production on territory retention in Arctic-breeding Pacific and Yellow-billed loons

The Condor ◽  
2019 ◽  
Vol 121 (1) ◽  
Author(s):  
Brian D Uher-Koch ◽  
Kenneth G Wright ◽  
Joel A Schmutz
Keyword(s):  
Coastal Plain ◽  
Oil And Gas ◽  
Breeding Habitat ◽  
Retention Rates ◽  
The Arctic ◽  
Oil And Gas Development ◽  
Brood Rearing ◽  
Site Familiarity ◽  
Northern Alaska ◽  
The Impact

Abstract Adult birds may use the production of offspring as a measure of habitat quality when prospecting for territories, increasing competition for productive territories. We evaluated the impact of breeding success on territory retention of Pacific (Gavia pacifica) and Yellow-billed (G. adamsii) loons in the National Petroleum Reserve-Alaska on the Arctic Coastal Plain of northern Alaska using mark–resight data and multi-state modeling. We also used behavioral observations of brood-rearing adult loons to quantify the frequency of visits by prospecting loons. We hypothesized that increased competition for productive territories would result in a decrease in territory retention rates. Territory retention rates the year following successful breeding attempts were only slightly lower (0.90) than after failed breeding attempts (0.93), and few territories were consistently successful across years. Overall territory retention rates were high (0.92) and similar for both species, suggesting that adults were able to defend their territories successfully. Males had higher territory retention rates than females, but we found no influence of mass (a possible proxy for fighting ability) on territory retention. These observations, coupled with the high frequency of visits by prospecting loons, provide additional evidence that site familiarity may provide advantages to territory holders. Quantifying territory retention behaviors may also inform land management decisions for oil and gas development in areas where loons are present. High territory retention rates, frequency of visits by prospectors, and limited habitat where new territories can be established suggest that breeding habitat in northern Alaska is saturated and may be limiting Yellow-billed Loon populations. In contrast, Pacific Loons attempting to acquire a territory may be able to form new territories on smaller, unoccupied lakes.

Den ecology of the Arctic fox in northern Alaska

1969 ◽  
Vol 47 (1) ◽  
pp. 121-129 ◽  
Author(s):  
David L. Chesemore
Keyword(s):  
Plant Growth ◽  
Soil Texture ◽  
Ice Core ◽  
The Arctic ◽  
Arctic Fox ◽  
Soil Temperatures ◽  
Alaskan Arctic ◽  
Northern Alaska ◽  
Teshekpuk Lake

During July and August 1962, 50 Arctic fox dens were studied on The Teshekpuk Lake Section of the Alaskan Arctic Slope. Depth to permafrost and soil texture govern location of fox dens in low. ice-core mounds with a minimum mound height of 1 m necessary for the establishment of a successful den. Soil temperatures at den sites were higher than those in nearby non-den habitats. The presence of the fox den alters plant growth near the burrow, changing the typical tundra community into a lush, vigorous one dominated by grasses.

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