Beaver River Research Articles

Numerical modelling of toppling

Evidence of large-scale toppling deformation has been reported in association with deep-seated landslides affecting mountain slopes along the Beaver River valley, Glacier National Park, British Columbia, Canada. A study has been undertaken to quantitatively investigate the relationship between the toppling mass movement process and the deep-seated landslides; specifically, whether the landslides represent a limiting condition of the toppling process. This is the first of two papers that describe the study. Methods of toppling analysis, including limit-equilibrium, finite-element, and distinct-element methods, are critically reviewed. The distinct-element method emerges as the best technique for modelling both block and flexural modes of toppling. The method is verified by modelling three examples of toppling: a theoretical block topple, a physical model of flexural toppling, and an engineered slope from the Brenda mine near Peachland, British Columbia. The results demonstrate that the Universal Distinct Element Code (UDEC) is capable of modelling both block and flexural types of toppling, that the toppling mass movement process limits to deep-seated planar aswell as curvilinear landslides, and that other landforms such as obsequent scarps and grabens are a manifestation of the toppling process. The research reported here contributes to understanding of the deformation behaviour of engineered slopes and the evolution of natural slopes in rock masses containing pervasive discontinuities. Key words: block toppling, flexural toppling, landslide, numerical modelling, distinct element, DDEC, sackung.

Late Pleistocene and Holocene lake fluctuations in the Sevier Lake basin, Utah, USA

Sevier Lake is the modern lake in the topographically closed Sevier Lake basin, and is fed primarily by the Sevier River. During the last 12000 years, the Beaver River also was a major tributary to the lake. Lake Bonneville occupied the Sevier Desert until late in its regressive phase when it dropped to the Old River Bed threshold, which is the low point on the drainage divide between the Sevier Lake basin and the Great Salt Lake basin. Lake Gunnison, a shallow freshwater lake at 1390 m in the Sevier Desert, overflowed continuously from about 12000 to 10000 yr B.P., into the saline lake in the Great Salt Lake basin, which continued to contract. This contrast in hydrologic histories between the two basins may have been caused by a northward shift of monsoon circulation into the Sevier Lake basin, but not as far north as the Great Salt Lake basin. Increased summer precipitation and cloudiness could have kept the Sevier Lake basin relatively wet.

Essay of Hydrology XXXVI: Beaver River of Novascotia (Ⅱ)

Essay of Hydrology XXXVI: Beaver River of Novascotia (Ⅱ)

Pre-Keweenawan anorthosite inclusions in the Keweenawan Beaver Bay and Duluth Complexes, northeastern Minnesota

Large numbers of calcic anorthosite inclusions varying in size from centimetres to several hundred metres occur in the Beaver River gabbro unit of the Beaver Bay Complex exposed along the North Shore of Lake Superior. Lesser numbers of similar inclusions occur in the Duluth Complex. Both host rocks crystallized at about 1.13 b.y. B.P. and are of Keweenawan age. The inclusions have been divided into four groups, based on outcrop and petrographic data, as follows: (1) Tectonite inclusions that were sheared and recrystallized. The tectonites consist of plagioclase (An 76–78 ), minor to accessory olivine (Fo 78 ), and accessory magnetite-ilmenite. (2) Igneous inclusions that have igneous structures and textures. Plagioclase ranges in composition from An 54 to An 80 . Principal mafics are augite (Wo 40 En 45 Fs 15 ) and orthopyroxene (Wo 2 En 80 Fs 18 ), but more iron-rich pyroxenes (Wo 38 En 40 Fs 22 ), including pigeonite (Wo 10 En 55 Fs 35 ), occur as much smaller grains in most igneous inclusions and are comparable to pyroxenes in host rocks. Textural evidence and mineral chemistry suggest that the Fe-rich pyroxenes, as well as the more albitic plagioclase, represent contamination. (3) Intermediate inclusions whose textures are intermediate between the tectonites and igneous rocks. Some of these appear to have been incompletely recrystallized, and some were modified to more igneous-appearing rocks by reaction with host rocks. (4) Cataclastic and brecciated inclusions having brittle deformation that is not apparent in the host rocks. Representatives of each group were analyzed for rare-earth elements (REE) and Sm-Nd, Rb-Sr isotopes. The chemical data correlate with the textural groups. For example, tectonites have low REE abundances with Nd about one times chondrites, whereas those in the igneous-textured group have higher REE abundances with Nd up to as much as seven times chondrites. Isotopic data show that the isotopic systems of the inclusions were disturbed and that contamination was introduced. Tectonites have 87 Sr/ 86 Sr and 143 Nd/ 144 Nd ratios that are less than those of the Beaver River gabbro when recalculated to 1.13 b.y. Igneous-textured inclusions have 143 Nd/ 144 Nd ratios that are lower than tectonite values at 1.13 b.y., but 87 Sr/ 86 Sr ratios vary widely, with some being greater than ratios in the host Beaver River gabbro. None of the inclusions has an isotope ratio that would allow a co-magmatic relationship with either the Duluth Complex or the Beaver River gabbro. Sm-Nd data from an incompletely equilibrated inclusion suggest recrystallization between 1.14 b.y. B.P. and 1.9 b.y. B.P., perhaps as a result of the 1.8 b.y. B.P. Penokean event. Calculations of a crystallization age for the inclusions are speculative but suggest crystallization at or before 1.9 b.y. B.P.

Highway-Related Landslides in Mountainous Volcanic Terrain: An Example from West-Central Utah

Mountainous volcanic terrain presents a special challenge in avoiding highway-related landslides. Volcanic bedrock is commonly very susceptible to landsliding because of varying physical properties of the rocks and the abundance of potential failure surfaces. Mountainous terrain further limits the areas in which roads can be built and makes avoiding potential landslide areas difficult. Landslides along Utah Highway 153 along Beaver River Canyon in the Marysvale volcanic field of west-central Utah provide an example of the difficulties of road construction and maintenance in such terrain. Debris slides and rockslides are chronic problems along 5.1 km of this highway in Beaver Canyon where the road was built along a natural bench on the canyon slope that coincides with an inherently weak zone in the stratigraphic succession of the volcanic bedrock. Numerous landslides have resulted, with attendant costly operational and environmental consequences. Detailed, comprehensive geologic investigations are clearly a necessary prerequisite to locating roads in mountainous volcanic terrain. (Author)

Eastern Cordilleran Foldbelt and Foreland of Northern Canada: ABSTRACT

The eastern Cordilleran foldbelt and foreland of Canada north of lat. 60°N lies between the Tintina trench and the Canadian shield. It includes part of the southern rim of Canada basin and the junction between the Cordilleran and Innuitian orogenes. The sedimentary succession rests with profound unconformity on the westward continuation of the crystalline rocks of the shield, tapering eastward to a zero edge against the shield but truncated northward at the outer edge of the continental shelf. Widespread unconformities within and beneath the succession attest to regionally episodic orogeny and epeirogeny from the Proterozoic into the Tertiary. In contrast to the tectonic style of equivalent thrust-faulted parts of the southern Canadian Cordillera, the region is characterized by bundles of right- and left-hand en echelon folds cut by two major, right-lateral strike-slip fault systems, the Richardson fault array bordering upon the foreland, and the Kaltag fault zone transecting the foldbelt. Laramide horizontal shortening with concomitant vertical thickening of the sedimentary succession is roughly one-fourth that at the 49th Parallel. Known reservoir rocks for hydrocarbons include lower Paleozoic platformal carbonate rocks just north of lat. 60°N in both the foreland (Rabbit Lake) and eastern margin of the foldbelt (Beaver River and Pointed Mountain); Middle Devonian reefs (Norman Wells) and lower Carboniferous sandstone traps (Chance) within the foldbelt; and most recently, shale-cored anticlines and growth-fault structures in the Tertiary clastic sequence on the continental shelf at the junction of the Cordilleran and Innuitian Orogens. End_of_Article - Last_Page 759------------

Beaver River Middle Devonian Carbonate: Performance Review of a High-Relief, Fractured Gas Reservoir With Water Influx

Beaver River Middle Devonian Carbonate: Performance Review of a High-Relief, Fractured Performance Review of a High-Relief, Fractured Gas Reservoir With Water Influx This paper discusses the performance history of Beaver River Field, located in British Columbia and the Yukon Territory. Development in this frontier location was supported by reserve estimates of more than 1 Tcf and high well deliverabilities. After production began in 1971, a severe decrease in recoverable reserves and deliverability resulted from water influx. Introduction When first produced, Beaver River Field [located 100 miles northwest of Fort Nelson on the border of British Columbia and the Yukon Territory (Fig. 1)] was thought to be British Columbia's largest gas field, with recoverable reserves estimated at more than 1 Tcf. Initial production rates of more than 200 MMcf/D from six wells were production rates of more than 200 MMcf/D from six wells were reduced after 2 years because of increased water production. Although production was curtailed to determine the cause of water production, this problem soon was overshadowed by reduced capacity resulting from increasing water/gas ratios. In 5 years, field rates have decreased from 230 MMcf/D to 3 MMcf/D. The field was shut in Oct. 1978. Because of the effects of water influx, ultimate recoverable reserves are estimated at 178 Bcf. Field Discovery and Development The Beaver River Anticline first was recognized in 1944 by the Geological Survey of Canada during a reconnaissance project. Amoco Canada Petroleum Co. Ltd., began exploring project. Amoco Canada Petroleum Co. Ltd., began exploring the area in 1954; the A-1 Beaver River well was drilled in 1958. This well was abandoned with lost drillstring in the hole in the Middle Devonian carbonate at 11,752 ft. However, the well indicated the presence of a potential gas-bearing horizon. In Jan. 1961, drilling began for Well A-2. This 13,500-ft well penetrated 1,200 ft of Middle Devonian carbonate without reaching the water contact. Testing established an absolute open flow (AOF) of 85 MMcf/D, while core analysis indicated average porosity of 3%. The success of this well justified exploratory drilling in the adjacent Pointed Mountain Anticline and supported the drilling of more Beaver River wells. From 1967 to 1970, continuous drilling led to successful completion of four additional gas wells at Beaver River. AOF potentials of up to 100 MMcf/D at Beaver River and 200 MMcf/D at Pointed Mountain, a 20-day high-rate flow test at Pointed Mountain (showing no apparent depletion), and evidence of good porosity all contributed to a favorable view of the area's potential. A sales contract based on reserves of 1.47 Tcf was signed, which led to the design and construction of a dehydration plant and transmission line. Production from the field began Oct. 1971. Stratigraphy and Structure Beaver River Field is located in a structural belt known as the Liard Plateau or the Liard Fold Belt, bounded by the Mackenzie Mountains on the north and the Rocky Mountains and foothills on the south. The main production at Beaver River is from a thick sequence of highly altered dolomites. Although these dolomites range in age from Middle Devonian through Ordovician, production is from the upper portion of this sequence. Here, the reservoir is called the "Middle Devonian carbonate. The Middle Devonian carbonate was deposited as a relatively monotonous carbonate and evaporite sequence in shallow subtidal to supratidal environments on a broad carbonate bank. JPT P. 1672

Beaver River Anticline and its Associated Giant Gas Reserve in Canada's Northland: ABSTRACT

The Beaver River gas field is located mostly in northern British Columbia at the approximate junction of the British Columbia-Yukon and Northwest Territories boundaries. The Beaver structure was mapped initially by E. D. Kindle in 1944, while working for the Geological Survey of Canada. Amoco Canada mapped the area in 1955, and as a result of its map interpretation, purchased the Crown lands over the Beaver River structure, as well as several other structures. The discovery well on the Beaver River structure was commenced in 1958 and completed in 1960. The excessive length of time required to drill the well resulted from continued problems, the most serious being a gas blow-out, which resulted in the death of 2 rig hands. A total of 6 follow-up wells has been drilled on the structure, proving a recoverable gas reserve of 1.4 trillion cu ft of gas. The gas reserve is in an anticline which can be mapped by surface geology and has been confirmed in the subsurface by conventional geophysical methods. The producing zone identified as of Middle Devonian age is a secondary dolomite with fair to good porosity and permeability. The porosity and permeability are improved substantially by fracturing associated with the structural deformation. Exploration in the area of Beaver River, while ideal relative to the standards of the surface geologist, is a nightmare of high costs and problems for the geophysicists and engineers. Access problems due to terrain variations, extreme cold in winter, and muskeg in summer, make normal operations extremely difficult and costly. The disturbed belt of Northeast British Columbia and the Yukon and Northwest Territories undoubtedly holds many more giant hydrocarbon accumulations similar to Beaver River. However, for exploration to flourish in these high-cost areas, exploration incentives are necessary. Reasonable assurance that hydrocarbons when found will get to market with as little delay as possible is a primary requirement. With increasing demand for fuel on the North American continent, Canada's northland gains prominence as a potential supplier. As the demand becomes more urgent, exploration for accumulations such as Beaver River should expand. End_of_Article - Last_Page 648------------

Pyroxenes from the Beaver Bay gabbro complex of Minnesota

Although the Beaver Bay ferrogabbro is a small-scale layered intrusion, Ca-rich pyroxenes show a strong iron enrichment during fractionation, ranging from augite (Mg38Fe24 Ca38) to ferrohedengergite (Mg10Fe48Ca42). Ca-poor pyroxenes from intermediate pigeonite (Mg39Fe50Ca11) to ferriferous pigeonite (Mg27Fe65Ca8) occur as intercumulus minerals. The pyroxenes from the non-layered Beaver River gabbro are included in the overall pyroxene fractionation trend of the Beaver Bay gabbro complex. The pyroxene trend of the Beaver Bay gabbro complex is similar to those of the Skaergaard and Bushveld; however, there is a slight difference in that the Ca-rich pyroxenes of Beaver Bay (having Mg content over 30%) are slightly richer in Ca than either the Skaergaard or Bushveld augites.

Devonian Gas Exploration in Northeastern British Columbia: Geology, Operations and Economics

Abstract Following indications of Devonian gas in several widely scatterednortheastern British Columbia wildcats drilled between 1954 and 1956, anaggressive programme of exploration for Middle Devonian gas was begun in the Fort Nelson area in the winter of 1956–57. Since this time the explorationeffort for Devonian gas has steadily increased, with new operators entering theplay, and new discoveries being added each year. All of these discoveries to date are in Middle Devonian beds, with theexception of the Pacific-Imperial Parkland well, which produces from the Upper Devonian Wabamun formation on the Peace River Arch. The discoveries lieentirely in the Plains area with the exception of Beaver River, which is in thefolded belt at the extreme northern edge of the Province. Most of the Middle Devonian fields discovered to date are in reefalcarbonates associated with the rim of a shale embayment which extends southeastinto British Columbia from the Yukon territory. Exploration for these fields isguided by a combination of seismic and subsurface stratigraphic methods. Faciesanalysis is particularly important to delineate favourable carbonateenvironments. Seismic operations and costs run about $70,000.00 per month and are affectedsignificantly by local terrain and weather conditions. Construction andmaintenance of access roads and trucking of rigs and supplies into the bush arealso major exploration expenses. In the drilling of exploratory wells for Middle Devonian gas, it has been common practice to set 300 feet of 13 3/8"surface casing, 2000 to 2500 feet of 9 5/8"intermediate casing through upper Mississippian porous carbonates, 7" casing to the top of the Slave Pointformation, and a 5" liner through the productive zone. Development wells can becompleted in open hole beneath the 7" casing, usually giving higher absoluteopen flow and deliverability rates. With increasing activity drilling costs have been steadily reduced. In theimmediate area of Fort Nelson wells can now be drilled to the Slave Point in 20to 25 days for as little as $100,000.00 and an open hole completion made for$150,000.00. At more remote locations, costs have been appreciably higher.

Bacteriological Studies of Freshwater Fish: II. Furunculosis in Ontario Fish in Natural Waters

During a period of 29 months, 1044 fish were taken from different sections of 10 streams in southern Ontario and examined for the presence of Aeromonas salmonicida, the bacterium causing furunculosis in fish. Most of the fish examined were brook trout (Salvelinus fontinalis), and carriers of furunculosis were, with one exception, found only in this species of fish. The one exception was a sculpin (Cottus bairdi). Most of the brook trout found to be carriers were taken from the same section of the Beaver River. As yet, no explanation can be given of the high incidence of furunculosis carriers in these waters, nor is their importance known.

The Taxonomic Status of Oklahoma Beavers, Castor canadensis

Study of the skulls of Oklahoma beavers and comparison with speci- mens from Texas and Kansas shows that individuals from the Red River drainage are referable to Castor canadensis texensis, those from the Arkansas River drainage to C. c. missouriensis. Local names, such as Beaver River, common knowledge among old settlers, and occasional records such as those of Chouteau's trading post, all attest to the fact that at one time beaver were widespread in Oklahoma. Indiscriminate trapping led to their decimation without specimens from early years being deposited in museums. Blair (1939) was unable to cite specimens in his extensive survey of Oklahoma mammals. He cited two literature references to beaver by Snider (1917) and Marcy (1854), and reported some old tree cuttings seen at Wekiwa on the Arkansas River west of Tulsa sometime prior to 1939. In his opinion beaver, at the time of writing, were almost or completely extirpated from the State. Duck and Fletcher (1943), however, noted that the bulk of Oklahoma's beaver population oc- curred on the Washita and North Canadian Rivers, with other colonies in Atoka, Pushmataha, and Pawnee counties. In the absence of speci- mens, Blair postulated that the beaver of eastern Oklahoma might be referable to the subspecies carolinensis, and that of western Oklahoma to texensis. McCarley (1952) recorded two colonies of C. canadensis from Bryan County, but did not allocate them to subspecies, as the animals themselves were not critically examined. Hall and Kelson (1958) indicated that the beaver of the northern one-fourth Oklahoma (including the panhandle) should belong to the subspecies missouriensis and those from the remainder of the State, including McCarley's record, should be texensis. They referred the beaver of the South Canadian River in Texas to the subspecies texensis on the basis of a reference by Bailey (1905). However, examination of Bailey's original comment reveals that he was quoting a report by Howell (evidently an oral account as no reference is cited) that beaver oc-

Rare Shrews from Utah and Wyoming

The collection of mammals in the Museum of Zoology, University of Utah, contains representatives of two rare species of shrews of the genus Sorex . These specimens were obtained from Utah and Wyoming during 1952–1954. Because of their rarity, and inasmuch as their localities of capture extend the known areas of occurrence, we considered it worthwhile to report upon them. This research was financed in part by a grant from the National Science Foundation. Sorex merriami leucogenys Osgood.—Osgood (Proc. Biol. Soc. Washington, 22: 52, April 17, 1909), on the basis of a single specimen, named this subspecies as Sorex leucogenys . The type locality is “Mouth of the canyon of Beaver River, about 3 miles east of Beaver, Beaver County, Utah.” Despite intensive collecting, no additional specimens were reported for 26 years, when Benson (Univ. California Pubis. Zool., 40: 439–455, December 31, 1935), reported upon five specimens from War God Spring, Navajo Mountain, San Juan County, Utah. Since 1935, although …

Release, Dispersal, and Reproduction of Fallow Deer in Nebraska

Because of the fine sporting qualities of the fallow deer, Dama dama Linnaeus, it has been introduced in many parts of the world. In the United States this deer has been released in several places, but little has been published as to the success of these introductions. It seems desirable therefore to note that fallow deer have been released in the state of Nebraska (Fig. 1). Fig. 1 —Locality records of fallow deer in Nebraska: 1. Where fallow deer were released. 2. Where fallow deer were observed to mate. 3. Where Sather obtained his information (also at point 1.). 4. and 5. Author's observations in 1954. 6. Agar's report of occurrence. The exact date of the release of the fallow deer in Nebraska is unknown; however, Mr. James H. Agar, Superintendent of the Lincoln, Nebraska, Park Department ( in litt. , October, 1953) writes, “In the late 1930's, the City Park Department took approximately sixty white fallow deer to the Hall Ranch ten miles northwest of Petersburg, Nebraska”. This point of release was in the middle of the Beaver River Valley, which is on the southeastern edge of the Nebraska sandhills in Boone County. In this valley there are extensive hay fields, good willow growths, and some corn fields. Dr. J. Henry Sather, Leader, Pitt-man-Robinson Surveys and Investigations for the State of Nebraska Game Forestation and Parks Commission, also reported ( in litt. , June, 1954) that in 1946 he found fallow deer in Boone and Wheeler counties. He interviewed six residents in Wheeler County and one in Boone …

Beaver River Supply and Low‐Flow Augmentation

Beaver River Supply and Low‐Flow Augmentation

The Correlation of the Lower Allegheny-Pottsville Section in Western Pennsylvania

The reports of the Second Pennsylvania Geological Survey covering the region along the Beaver River and its tributaries in Lawrence, Mercer, and Butler counties, show that the average interval between the Vanport limestone of the Allegheny group and the Homewood formation (sandstone), the youngest member of the Pottsville series is 50 feet. In the Foxburg quadrangle along the Allegheny River, the average interval is 120 feet from the Vanport limestone down to what is called the Homewood sandstone in that folio. The present writer, however, concludes that the Upper Connoquenessing and Homewood sandstones of the Beaver River section are equivalent to the Homewood and Clarion sandstones of the Allegheny River section. The Pottsville series of the Foxburg folio should, therefore, be extended to include the Clarion formation of the Allegheny group and the Clarion sandstone should be regarded as the top member of the Pottsville series in the Allegheny River section. A study of the same members between Mayport near the eastern margin of the Clarion quadrangle and Brookville in Jefferson County, suggested that the Craigsville coal of the Foxburg-Clarion folio is the equivalent of the Brookville coal near Brookville.

Notes on the Birds of the Beaver River Valley in Saskatchewan

Notes on the Birds of the Beaver River Valley in Saskatchewan

Northward flow of ancient Beaver river

Introduction In 1890, in connection with Doctor Foshay, the writer discussed somewhat briefly the abandoned fluvial plains of Beaver river, and attention was called to the evidences of the direction of flow of the stream that eroded the fluvial plain that is now found high above the present stream level[*][1]. With the evidence that is furnished of the ancient slope by the fragments that are still to be found, attention is here specially directed to the evidence furnished by pot-holes found on the old river bed near Rock point. History of Beaver River The life history of Beaver river may be divided into a number of stages. One of the earlier stages is the time when it formed the line of northern discharge for the upper Ohio drainage, the fluvial plain above mentioned forming one of the later beds of the river at this stage of its history. This stage . . . [1]: #fn-1

Glacial Grooves at the Southern Margin of the Drift

Introductory Note. In a preliminary paper in the American Naturalist for September, 1890,* there was a brief sketch of the phenomena herein described in greater detail and illustrated by photographs reproduced, mechanically (plate 18). These phenomena, consisting of grooves, striae and potholes, were discovered by the writers in the course of a survey of the Pleistocene formations of the valley of the Beaver river. The description of the particular phenomena in which we are interested is here prefaced by a short account of some of the features and the geological history of this portion of western Pennsylvania. Physiography of the Beaver Valley. The Beaver river is formed at Lawrence Junction, on the Pittsburgh, Youngstown and Azhtabula railroad, by the confluence of Mahoning and Shenango rivers, and, after a course of about twenty-one miles in a southerly direction, terminates by emptying into the Ohio river at Beaver. In its course it . . .