Alberta Foothills Research Articles

Grazing impacts on bulk density and soil strength in the foothills fescue grasslands of Alberta, Canada

Alberta foothills fescue grasslands are very productive ecosystems but there is concern that the traditional season-long (continuous) grazing regimes may be leading to soil deterioration due to compaction and increased soil strength. The objectives of this study were to quantify grazing effects on soil bulk density and soil strength of sloped areas in the Alberta foothills fescue grasslands at the Agriculture Canada Stavely Range Substation. The effects of two grazing intensities (heavy and very heavy) for two treatments (short duration and continuous) on these two parameters were compared to an ungrazed control. Soil bulk density and soil water to a depth of 7.5 cm were measured with a surface water/density gauge. Soil strength was measured with a hand-pushed cone penetrometer to a depth of 45 cm. Cone index, the maximum penetration resistance in a given depth interval, was used as a measurement parameter for soil strength.Grazing affected both soil bulk density and penetration resistance. Even short-duration treatments affected these soil properties, although their effects were similar for both heavy and very heavy grazing intensities. Distinction between heavy and very heavy continuous grazing treatments was clear for both bulk density and penetration resistance, with the very heavy treatment having the greatest detrimental effect on these two soil parameters for all treatments. Bulk density and soil strength values were always lowest in the spring after snowmelt and highest late in the growing season, reflecting the water status of these ecosystems. Identical treatment rankings were obtained using bulk density and penetration resistance, but cone index was a more sensitive indicator of the effects of grazing than bulk density. Key words: Grazing, fescue grasslands, bulk density, soil strength

AEC Highlander slender wheatgrass

AEC Highlander slender wheatgrass, Elymus trachycaulus (Link) Gould in Stunners subsp. trachycaulus, was developed for use in reclaiming and revegetating disturbed sites in the mountains and foothills of Alberta. Its primary advantage over other varieties is its ability to grow rapidly and produce mature seed in the short growing seasons found at higher elevations. Key words: Slender wheatgrass, Elymus trachycaulus, cultivar description, reclamation

Coal rank, distribution, and coalbed methane potential of the Lower Cretaceous Luscar Group, Bow River to Blackstone River, central Alberta Foothills: F. M. Dawson & W. D. Kalkreuth, Bulletin — Geological Survey of Canada, 473, 1994, 52 pp, 8 maps

Coal rank, distribution, and coalbed methane potential of the Lower Cretaceous Luscar Group, Bow River to Blackstone River, central Alberta Foothills: F. M. Dawson & W. D. Kalkreuth, Bulletin — Geological Survey of Canada, 473, 1994, 52 pp, 8 maps

A Microcomputer‐Based Geographic Information System for Hydrologic Simulation

Abstract: A microcomputer‐based geographic information system (GIS) supporting hydrologic simulation is described. The hydrologically‐oriented GIs can automatically provide parameters required for prediction of flood hydroghraphs and physically‐based synthetic flood frequency curves for ungaged watersheds. The hydrologic model uses the Soil Conservation Service (SCS) runoff curve number (CN) method and a synthetic unit hydrograph to represent the physical transformation of rainfall into runoff The standard SCS method was modified to account for randomness of key parameters whose probability distributions can be derived from regional rainfall and runoff data. The GIs, and hydrologic theory and techniques, including the modified SCS method, derivation of a regional dimensionless unit hydrograph, and Monte Carlo simulation procedure, are described. Results of hydrologic analysis and simulation by the system implemented for an area of 11000 km2 in the Alberta foothills are presented.

Coal deposits in the front ranges and foothills of the Canadian Rocky Mountains, southern Canadian Cordillera

Canada has the fifth largest inventory of coal resources in the World. More than one-third of Canada's resources currently favourable for exploitation occur in the southern Canadian Rocky Mountains, with major deposits in the Front Ranges, Inner Foothills and Outer Foothills physiographic provinces. In the Front Ranges, major deposits of metallurgical and thermal, high-volatile bituminous to semi-anthracite coal occur in the Late Jurassic-Early Cretaceous Mist Mountain Formation. In the Inner Foothills of northeastern British Columbia and west-central Alberta, significant resources of metallurgical and thermal, medium- and low-volatile bituminous coal occur in Early Cretaceous strata of the Gething (Aptian) and Gates (Albian) Formations. In the Outer Foothills resources of thermal, high-volatile bituminous coal occur in Late Cretaceous and Paleocene strata of the Belly River (Campanian), Coalspur (Maastrichtian-Paleocene) and Paskapoo (Paleocene) Formations. The major coal deposits of the Front Ranges and Inner Foothills accumulated within the coastal plains of the Fernie and Moosebar-Clearwater seas, respectively. Shorelines prograded to the north and northeast into a foreland basin that evolved in advance of, and in response to, the evolving Columbian Orogen. In the Outer Foothills, coal deposits of the Belly River Formation originated within prograding coastal plains during the withdrawal of the Pakowki Sea. The major coal deposits of the Coalspur and Paskapoo Formations accumulated in the alluvial plain environments of the foreland basin during the Laramide orogeny. Coal measures of the southern Canadian Rocky Mountains were variably folded and faulted during the Laramide orogeny (Late Cretaceous-Eocene). Structural deformation has significantly affected the mineability and quality of the coals. Many of the coal seams are sheared, structurally thickened or thinned and repeated by thrust faults or truncated by normal faults. Shearing of the seams in adjacent hanging and footwall strata has led locally to pronounced oxidation, resulting in weak coal pillars and roofs in underground mines. Faulting and folding has partitioned many coal deposits into discrete structural domains of varying style and complexity, each of which can present a unique challenge in designing optimum coal extraction methods. The variation in coal rank in the southern Canadian Rocky Mountains mainly reflects the preorogenic (pre-Laramide) depth of burial. In some areas, however, there is evidence for syn- and post-orogenic coalification, resulting from the emplacement of thick overthrust sheets and/or deposition of thick Tertiary molasse, most of which has been subsequently eroded. With few exceptions, coals of the southern Canadian Rocky Mountains are characterized by low sulphur contents (< 1%) and ash yields that range from 10% to 30%. The maceral composition of the coals is highly variable; Late Jurassic and Early Cretaceous coals are known for high percentages of semi-fusinite (ca. 30%) and Late Cretaceous and Paleocene coals for high vitrinite contents compared to most coals. All of the coal-bearing stratigraphic successions include multiple, thick seams and all existing mining operations are designed to extract and, where necessary, blend multiple seams.

The Causes of Severe Convective Outbreaks in Alberta. Part I: A Comparison of a Severe Outbreak with Two Nonsevere Events

Abstract Abstract Mesoscale and synoptic-scale analyses were carried out for a severe convective outbreak and two nonsevere convective events in central Alberta. High-resolution upper-air and surface observations gathered during the Limestone Mountain Experiment (LIMEX-85) permitted a detailed diagnosis of the evolution of the atmosphere over the Alberta foothills. On the severe day, deep convection was triggered when upper-level cooling, associated with an advancing, synoptic-scale trough, occurred in phase with strong surface heating over the Alberta foothills from 0800 to 1200 local daylight time (LDT). The deep destabilization over the elevated topography acted to amplify the mountain-plain circulation and to generate mesoscale upslope moisture transport. Concurrently, the surface synoptic pressure gradient gave rise to northeasterly winds that advected a tongue of moist plains air into the lower branch of the mountain-plain circulation. The plains moisture was thus permitted to reach the foothills in...

The Causes of Severe Convective Outbreaks in Alberta. Part II: Conceptual Model and Statistical Analysis

Abstract An intercomparison of all 11 Limestone Mountain Experiment case days provided the basis for a conceptual model of severe convective outbreaks in Alberta. It is proposed that most severe convective events result when upper-level cooling, associated with an advancing, synoptic-scale trough, occurs in phase with strong surface heating over the Alberta foothills. The deep destabilization over the elevated topography acts to amplify the mountain-plain circulation and to generate mesoscale upslope moisture transport. Concurrently, the surface synoptic pressure gradient gives rise to east-northerly winds that advect the moisture-rich air of the eastern plains into the lower branch of the mountain-plain circulation. In this manner, the plains moisture is permitted to reach the convectively active foothills through underrunning of the capping lid. The end product is the initiation of well-organized, severe convective storms that move eastward with the westerly component of the midtropospheric winds. A sta...

The influence of opening size on snow evaporation in the forests of the Alberta Foothills

Insitu snow evaporation was measured in circular openings, from 0H (full forest) to 5H (where H is the height of the surrounding trees; approximately 20 m), cut in the lodgepole pine (Pinuscontorta Dougl.) forest of the Alberta Foothills. Additional measurements were also made in a large 40H irregular clearing. The ratios of snow evaporation measured in the circular clearings to that measured in the large irregular opening were 0.24, 0.23, 0.28, and 0.41 for the 0H, 1H, 3H, and 5H, respectively. The aerodynamic approach yielded a good estimate of average daily snow evaporation in the large opening, with a computed value of 1.01 mm versus a measured one of 1.07 mm. Snow evaporation in the 0H opening was enhanced over that attributable to turbulent transport by nighttime radiative transfer from the canopy, which kept the snow warmer than in the other openings and prevented condensation. Vertical transfer efficiencies, the slope of the curve relating snow evaporation to the product of horizontal wind speed and vertical humidity gradient, were similar in all clearing sizes in spite of possible fundamental differences in wind fields created by the various canopy–opening interactions. Comparison of data from smaller openings with data from a previous study by A.J. West suggests that differences in snow evaporation between openings can be indexed to opening size.

Structure and Stratigraphy of the Southern Alberta Foothills, Grease Creek Syncline Area

Structure and Stratigraphy of the Southern Alberta Foothills, Grease Creek Syncline Area

Passive-Roof Duplexes Under the Rocky Mountain Foreland Basin, Alberta (1)

Seismic reflection data in the Central Alberta Foothills near Edson reveal the presence of small passive-roof duplexes in Upper Cretaceous rocks within the otherwise undeformed foreland basin, as much as 40 km northeast of the mountain front monocline. The tops and bottoms of the duplexes are defined by backthrusts and sole thrusts, which follow bedding planes within Upper Cretaceous strata. Overlying the structures is an essentially uncontracted 1.8-km-thick section of Upper Cretaceous and Tertiary rocks, which is passively uplifted over the thickened duplexes. The underlying autochthonous sequence of Mesozoic and Paleozoic rocks exhibits some minor folding but is also uncontracted. Our interpretation extends both the upper and lower detachments of the widely accepted triangle-zone model more than 30 km farther under the foreland basin than has previously been supposed. The seismic data illustrate relatively clearly the form of the leading edge of the last phase of Rocky Mountain thrusting. We expect that similar features will be observed elsewhere in the Rocky Mountain foothills and, probably, at other mountain fronts worldwide.

Early warning of slope instabilities by microseismic monitoring : Proc 4th Conference on Acoustic Emission/Microseismic Activity in Geological Structures and Materials, Pennsylvania, 22–24 October 1985 P511–529. Publ Clausthal-Zellerfeld: Trans Tech Publications, 1989

Pursuant to the technology transfert agreement between CANMET and USMB, microseismic monitoring was undertaken in a large opin pit coal mine in the Foothills of Alberta, Canada. The field test monitored a slope where instabilities were expected. This paper also refers to attempts made to develop and understanding of the event's location in relation to the displacements developed in the slope

A palaeoenvironmental study of Fairfax Lake, a small lake situated in the rocky mountain foothills of west-central Alberta

Fairfax Lake is a small, oligotrophic to mesotrophic headwater lake situated in the Foothills of the Rocky Mountains of west-central Alberta (Latitude 52° 58′ N; Longitude 116° 34′ W). Through acquisition of a sediment core, and analyses of the diatoms, chrysophyte stomatocysts, pollen and sedimentary pigments, including myxoxanthophyll and oscillaxanthin, a palaeoenvironmental history of the lake has been determined. The sedimentary record spans ca. 13 200 years. An open tree-less vegetation existed in the region ca. 13 200–ca. 11 600 years BP. Maximum oscillaxanthin and myxoxanthophyll concentrations, hence the largest blue-green algal populations, occurred during the same interval. With increasing temperature pioneering parkland vegetation appeared ca. 11 600 years BP but was replaced ca. 10 100 years BP by spruce forest. Pine appeared ca. 7800 years BP and this marked the development of the present day montane boreal forest. Diatoms were not found until ca. 11 255 years BP. Benthic taxa dominated but by ca. 10 100 years BP planktonic taxa had become more prominent. Lake levels are interpreted as having risen, and the lake water was probably more transparent. Maximum chlorophyll and total carotenoid concentrations occur ca. 11 255 to ca. 7000 years BP corresponding to the warm early to mid-Holocene period. Lake nutrient levels appear to have been higher prior to ca. 7000 years BP, and the lake has changed from being eutrophic during the early Holocene to its present status as an oligotrophic to mesotrophic lake. Subtle hydrological changes have also occurred in the catchment as water levels do not appear to have remained constant.

Chinooks and winter evaporation

Chinooks are warm mountain winds which occur in the foothills of southern Alberta. They are often blamed for encouraging droughts in the western prairies because of the link believed to exist between them and excessive surface and subsurface evaporation. Measurements made over four winters show that evaporation rates during a chinook exceed the net radiation flux when there is water standing over the surface. However, the vapour flux fraction reduces to a level below the potential rate once the moisture content drops below saturation level within the upper subsurface layer no thicker than 2 mm. Meanwhile, the soil moisture reservoir below that layer remains virtually undepleted even in the face of persistently strong chinook events.

Palynostratigraphic zonation of Paleocene strata in the central and south-central Alberta Plains

Paleocene strata of the Scollard and Paskapoo formations in the central and south-central Alberta Plains can be subdivided into five formal biostratigraphic zones, based in part on a Momipites–Caryapollenites palynofloral lineage. A similar zonation previously identified from strata of the Wind River basin in Wyoming displays similar palynomorph occurrences. However, differences that are present are likely a result of latitudinal climatic zonation between Alberta and Wyoming during Paleocene time.Lowermost Paleocene strata of Alberta (Wodehouseia fimbriata Zone) are barren of Momipites species, which subsequently first appear in the Momipites wyomingensis Zone. These two zones include strata from the Cretaceous–Tertiary boundary (Nevis coal seam) to the top of the Scollard Formation. A diverse assemblage of Momipites spp. plus Aquilapollenites spinulosus, Caryapollenites prodromus, and Tiliaepollenites danei are present in the Aquilapollenites spinulosus Zone within the lowermost Paskapoo Formation. Two more species of Caryapollenites appear in the Caryapollenites wodehousei Zone. The Pistillipollenites mcgregorii Zone is characterized by the presence of Pistillipollenites mcgregorii, Insulapollenites rugulatus, and Caryapollenites inelegans. Momipites leffingwellii is absent from the lower portion of this zone, with Momipites waltmanensis, Momipites actinus, and Momipites triorbicularis absent from the upper portion. Lower P. mcgregorii Zone strata are the youngest strata encountered in the vicinity of the Red Deer River valley. Upper P. mcgregorii Zone strata include strata of the Obed–Marsh coal zone within the uppermost part of the Paskapoo Formation adjacent to the Alberta Foothills.

Revised Definitions for the Upper Cretaceous Bad Heart Formation and Associated Units in the Foothills and Plains of Alberta and British Columbia

ABSTRACT Recent work on the Coniacian-Santonian Muskiki, Marshybank and formations of the Upper Cretaceous Alberta Group has shown that the facies change from shale to siltstone and sandstone that marks the base of the Marshybank in the Foothills type area can be traced in the subsurface as a continuous horizon throughout the basin. Sandstones and siltstones of the Marshybank are abruptly overlain by dark marine shales of the Dowling Member; this contact is also readily traced in well logs. The Formation of the type area in the Plains typically comprises a ferruginous, oolitic, silty sandstone. Similar oolitic sandstones are not present in the Marshybank and 'Bad Heart' of the Foothills. The top of the Marshybank is covered in chert pebbles and marks a regional disconformity. This surface and its associated pebble bed can be traced from the Foothills into the Plains, where it marks the base of the Formation. These relationships suggest that it is logical to redefine the Marshybank to include not only the siltstone and sandstone as originally defined, but also the equivalent strata present in the Foothills north of the Smoky River. The term Formation should be restricted to the oolitic sandstone and sandy siltstone present in the type area and traceable in the adjacent outcrop and subsurface. These rocks are not only lithologically distinct from the 'Bad Heart' (Marshybank) of the Foothills, but are separated from the latter by a regionally traceable disconformity. This clarification will facilitate discussion of the depositional history of these rocks. RESUME Des travaux recents portant sur les formations Coniaciennes-Santoniennes Muskiki, Marshybank et Heart, du groupe Alberta du Cretace superieur, ont demontre que les changements de facies de schiste argileux a microgres et gres qui marquent la base de la formation Marshybank dans la region type des piemonts peuvent etre retrouves dans la subsurface sous forme de niveau stratigraphique ininterrompu a la grandeur du bassin. Les gres et les microgres de la formation Marshybank sont suivis abruptement par les schistes argileux fonces du membre Dowling; ce contact est aussi nettement visible dans les diagraphies de forage. La formation de la region type des plaines comprend typiquement un gres silteux oolitique ferrugineux. Des gres oolithiques semblables ne se retrouvent pas dans les formations Marshybank et Bad Heart des piemonts. Le haut de la formation Marshybank est recouvert de galets de chert et represente une discordance stratigraphique regionale. Cette surface, ainsi que la couche de galets qui lui est associee, peut etre suivie a partir des piemonts jusque dans les plaines, ou elle marque la base de la formation Heart. Ces relations suggerent qu'il est logique de redefinir la formation Marshybank afin d'y inclure non seulement les microgres et les gres telle que definie a l'origine, mais aussi les strates equivalentes qui se trouvent dans les piemonts au nord de la riviere Smoky. Le terme formation devrait etre restreint aux gres oolithiques et aux microgres sableux presents dans la region type et qui se retrouvent dans les affleurements et dans la subsurface adjacents. Ces roches sont non seulement differentes du point de vue lithologique de la formation Bad Heart (Marshybank) des piemonts, mais sont separees de cette derniere par une discordance stratigraphique qu'on retrouve a l'echelle regionale. Cette clarification facilitera la discussion de l'histoire stratigraphique de ces roches. Traduit par Marc Charest

Detrital modes of sand and sandstone derived from andesitic rocks as a paleoclimatic indicator

The effect of climate on the composition of volcanic sand is tested by determining detrital modes of modern stream sands derived from high-relief, andesitic rocks in areas of contrasting humid and semi-arid climates. The three humid sample areas, Mt. Pelee, Mt. Fuego, and Mt. Rainier, consist of active volcanoes and associated Neogene rocks, whereas the three semi-arid sample areas are underlain by Oligocene and Miocene (southwestern Colorado), Eocene (southwestern New Mexico), and Late Cretaceous (southwestern Montana) volcanic rocks. Point-counts of the medium sand-sized fraction of 66 samples (35 semi-arid, 31 humid) indicate that the ratio of volcanic rock fragments to plagioclase plus volcanic rock fragments (RFP index) and the ratio of volcanic rock fragments to accessory minerals (primarily monocrystalline pyroxene, amphibole, or biotite) plus volcanic rock fragments (RFA index) are statistically lower in humid regions, reflecting a greater degree of chemical breakdown of the parent rock and gravel- and sand-sized rock fragments and release of monocrystalline grains. The RFP index is applied as a paleoclimatic indicator to Late Cretaceous and Paleocene foreland-basin sandstones of the southern Foothills of Alberta, Canada. Interpretations of changes through time in paleoclimate based on the RFP index correlate closely with independent interpretations of paleoclimate based on the distribution of coal and caliche.

Postglacial palaeoecology of the subalpine forest — grassland ecotone of southwestern Alberta: New insights on vegetation and climate change in the Canadian rocky mountains and adjacent foothills

Postglacial vegetation change at the subalpine forest-grassland ecotone in the foothills of southwestern Alberta is reconstructed from fossil pollen, plant macrofossils and fossil charcoal. The fossils were obtained from the sediments of a small lake. Chronological control for the record is provided by tephra analysis and the 14C dating of terrestrial plant macrofossils. The fossil record is compared with the results from similar studies at sites in the Rocky Mountains and foothills of Alberta and British Columbia. The comparison of vegetation change at the upper and lower elevational limits of the subalpine forest provides a record of changes in temperature and aridity over the Holocene. At 10,000 yr B.P. the study site supported a shrub and herb dominated vegetation. Picea-Pinus-Abies forests were present at mid- to high-elevations in the mountains and in the northern foothills by this time. The climate in the southern foothills was likely arid, but not severely cold. A relatively open Picea and Pinus forest was established in the study area between 9400 yr B.P. and 8000 yr B.P. Fire activity in the region was at a postglacial maximum during this period. The transition to forest suggests moister conditions. By 8000 yr B.P. the importance of members of the Chenopodiaceae-Amaranthaceae and Typha latifolia increased suggesting an onset of arid conditions characterised by low and fluctuating water levels in lakes. Between 8000 yr B.P. and 5000 yr B.P. the Picea and Pinus contorta forest at the study site was largely replaced by grassland and Pinus flexilis. At high-elevation sites treeline was located above its modern position during this period. Little vegetation change is recorded at sites in the northern foothills and at mid-elevations at this time. The vegetation change in the southern foothills and at high-elevations suggests both an elevational and latitudinal displacement of vegetation zones during the mid-Holocene. Warm and arid conditions were prevalent in southwestern Alberta. Picea glauca-Pinus contorta-Populus tremuloides forest has occupied the site since 5000 yr B.P., when cooler and moister conditions were established.

Performance validation of the Gueymard sky radiance model

Abstract The Gueymard model of short‐wave sky radiance has been validated against sky radiance date measured in the Rocky Mountain foothills of Alberta. Except for sky points within the circumsolar region in clear skies and for low sun positions in near overcast skies the model performs as well as other current sky radiance models.

Provenance of post-Wapiabi sandstones and its implications for Campanian to Paleocene tectonic history of the southern Canadian Cordillera

Late Campanian to Early Paleocene sandstones of the Alberta Foothills were derived from three types of rocks: (i) andesitic–dacitic volcanic rocks that were presumably comagmatic with middle to late Mesozoic plutons in the Omineca Crystalline Belt; (ii) low-grade metamorphic rocks in the suprastructure of the Omineca Crystalline Belt; and (iii) sedimentary rocks in die Rocky Mountain Thrust Belt, principally pelitic rocks in the western Main Ranges and carbonates and chert-arenites in the eastern Main and Front ranges. A paucity of quartzo-feldspathic rocks fragments and potassium feldspar indicates that the core of the Omineca Crystalline Belt was not extensively exposed at that time.Vertical trends in composition of the sandstones reveal five petrographic stages. Stage I is dominated by volcanic rock fragments and plagioclase, suggesting that initial progradation of the sediment was largely a response to coeval volcanism or tectonic emplacement of older volcanic rocks. Stages III and V are characterized by a significant decrease in the relative proportion of metamorphic detritus and an increase in the proportion of carbonate and chert detritus. These stages may represent periods of thrusting in the eastern Main Ranges or Front Ranges. In contrast, stages II and IV display increases in metamorphic detritus and stage II shows a concomitant decrease in carbonate and chert detritus, trends that indicate wearing down of the eastern Main Ranges or Front Ranges thrust sheet(s) and reintegration of the Omineca Crystalline belt and the western Main Ranges into the drainage basin. The compositional stages indicative of thrust events are associated with coarse facies, including the Entrance and High Divide Ridge conglomerates, whereas those stages indicative of tectonic quiescence are associated with fine-grained facies including coal.

Lithofacies Distribution and Continuity of Cardium Formation (Upper Cretaceous-Turonian) Tempestites, Alberta Foothills, Canada: ABSTRACT

Tempestite lithofacies associations recognized in previous studies of the Cardium Formation reservoir in the Pembina field have been identified and mapped in five outcrops in the Foothills of Alberta. Mesoscale and macroscale maps depicting the lateral continuity and distribution of this lithofacies association indicate that each lithofacies represents a lithosome. Significantly in the outcrops studied, the continuity of lithosome 4, whose flow capacity is an order of magnitude greater than that of other sandstone lithosomes in the Pembina field, decreases with increasing relative distance from shore.