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Articles 61 - 90 of 113
Full-Text Articles in Entire DC Network
Applications Of The Band-Limited-White Noise Source Model For Predicting Site-Specific Strong Ground Motions, Ivan G. Wong, Walter J. Silva, Robert B. Darragh, Cathy Stark, Douglas H. Wright
Applications Of The Band-Limited-White Noise Source Model For Predicting Site-Specific Strong Ground Motions, Ivan G. Wong, Walter J. Silva, Robert B. Darragh, Cathy Stark, Douglas H. Wright
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Since the Band-Limited-White-Noise (BLWN) source model coupled with random vibration theory (RVT) was first developed in the early 1980's, it has been used successfully to predict strong ground motions at rock sites in different tectonic regimes. The BLWN-RVT methodology is appropriate for an engineering characterization of strong ground motions at a site since the method captures the important features of these motions in terms of peak acceleration and spectral composition and requires a minimum of input parameters. Recently, the capability to estimate strong ground motions at soil sites has been incorporated into the methodology by using RVT and plane-wave propagators …
Structural Damage In A Populated Area Due To An Active Fault, N. Kalteziotis, N. Sabatakakis, G. Koukis, H. Zervogiannis, G. Tsiambaos
Structural Damage In A Populated Area Due To An Active Fault, N. Kalteziotis, N. Sabatakakis, G. Koukis, H. Zervogiannis, G. Tsiambaos
International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
The city of Patras was struck in August 1989 by a shallow earthquake of MS= 4.8 which caused a surface rupture and serious structural damage to several buildings located in a narrow elongated zone. A detailed investigation programme was carried out including geological mapping, drilling of boreholes, in situ and laboratory testing and monitoring of horizontal and vertical movements. It was found that the surface rupture, about 1500 m long, was closely related with the reactivation of a preexisting normal fault. The structural damage of buildings was found to be limited mainly in a narrow zone 50 m …
Geotechnical And Groundwater Site Characterization On The Umtra Project, J. A. Caldwell, R. A. Rager, L. Coons
Geotechnical And Groundwater Site Characterization On The Umtra Project, J. A. Caldwell, R. A. Rager, L. Coons
International Conference on Case Histories in Geotechnical Engineering
Reclamation of 24 inactive uranium mill tailngs piles involves remedial work to stabilize the piles for 1000 years. Site characterization of geotechnical and groundwater conditions at each site is undertaken prior to remedial action design. This paper describes the approach to UMTRA Project site characterization. A case history, Green River, is described. Details of site characterization costs for most sites are provided.
Hazardous Waste Disposal Site Hydrogeologic Characterization, S. M. Testa
Hazardous Waste Disposal Site Hydrogeologic Characterization, S. M. Testa
International Conference on Case Histories in Geotechnical Engineering
A major hazardous waste disposal facility near Arlington, Oregon serving the Pacific Northwest, Canada, and Alaska maintains numerous favorable environmental characteristics for siting of a hazardous waste disposal facility. The risk of contamination as a result of potential leakage from a waste management unit via primary pathways to surface water, groundwater or by direct contact and/or ingestion is thus reasonably low. However, these same characteristics which make the site most suitable for hazardous waste disposal often conflict with: 1) the demonstration of the groundwater monitoring system's ability to adequately perform immediate leak detection monitoring as mandated under the Resource Conservation …
A Study Of A Road Landslide In Puerto Rico, C. Rodriguez-Pérez, L. Vázquez Castillo, C. Rodriguez-Molina, A. Vázquez Castillo
A Study Of A Road Landslide In Puerto Rico, C. Rodriguez-Pérez, L. Vázquez Castillo, C. Rodriguez-Molina, A. Vázquez Castillo
International Conference on Case Histories in Geotechnical Engineering
Numerous landslides have plagued the construction of a 1.3 mile road sector in the mountainous region of central Puerto Rico. The area is underlain by a sequence of landslide deposits overlying a muddy limestone and hard overconsolidated clayey soils. Landslides have occurred in both cuts and fills that have delayed the road construction for a period of more than two years, bringing as a result, great economic losses for the Puerto Rico Highway Authority. The landslide trigger mechanism has been intimately related to high rainfall, commonly observed in this region. The geotechnical and geological studies performed previous to the construction …
Rock Mass Behaviour Assessment For Large Cavern In Rock, A. K. Dube, B. Singh
Rock Mass Behaviour Assessment For Large Cavern In Rock, A. K. Dube, B. Singh
International Conference on Case Histories in Geotechnical Engineering
A large power house cavern (22m x 50m x 250m) is proposed to be excavated for installing a 1000 MW hydroelectric power plant for Tehri Dam Project. The gorge chosen for the dam is very narrow and the topography is rugged and inhospitable. This dampened the process of preconstruction investigations. A number of tunnels were constructed for various project structures in the vicinity of the cavern. This provided an excellent opportunity to study the rock mass behaviour. Tunnel closure and rock loads were monitored with the help of instruments. Deformation moduli were also determined for different rock grades with the …
Slope Stabilization Measures For Kirkwood Penstock, Early Intake, California, K. D. Weaver, D. J. Gross, L. T. Bauer
Slope Stabilization Measures For Kirkwood Penstock, Early Intake, California, K. D. Weaver, D. J. Gross, L. T. Bauer
International Conference on Case Histories in Geotechnical Engineering
Kirkwood Penstock, located in a deep, steep-sided canyon near .Yosemite National Park, California, is an integral part of the Hetch Hetchy system, which conveys water from the Sierra Nevada Mountains to the city of San Francisco, California. A heavy rainfall approximately 17 years following construction of the facility triggered settlement of the foundation. Measures undertaken to arrest this settlement included consolidation grouting, construction of facilities to divert surface runoff away from the penstock, and installation of a geomembrane to prevent infiltration of rainfall and snow melt in the vicinity of the penstock. No evidence of further settlement has been detected …
Study Of Some Debris Avalanches In Garwal Himalaya, India, H. C. Nainwal, Y. P. Sundriyal, C. Prasad
Study Of Some Debris Avalanches In Garwal Himalaya, India, H. C. Nainwal, Y. P. Sundriyal, C. Prasad
International Conference on Case Histories in Geotechnical Engineering
This study was carried out in the Alaknanda - Dhauliganga catchment area, located in the north and northeast of Joshimath in the Garfiwal Himalaya. The snow fields, cirques and the related glaciers are located above the altitude approximate 4000 meters, while the river valley have a mean altitude of around 2000 meters. The strategic roads viz. Joshimath-Badrinath and Joshimath-Nitipass pass through this area with a number of villages along with their cultivated land are located along the roads. These roads are often blocked on huge debris avalanches not only damage the road, but also the cultivated land and forests. The …
Subsidence Movements And Structural Damage Related To An Abandoned Coal Mine, Y. P. Chugh, K. Chandrashekhar, R. J. Missavage
Subsidence Movements And Structural Damage Related To An Abandoned Coal Mine, Y. P. Chugh, K. Chandrashekhar, R. J. Missavage
International Conference on Case Histories in Geotechnical Engineering
An area in southwestern Illinois has been experiencing surface and subsurface movements with associated damage to surface structures. The area is underlain by an abandoned, partially extracted room-and-pillar underground coal mine. Instrumentation included TDR (Time Domain Reflectometry), Inclinometers, Sondex, Tiltplates, and precision land surveys. This paper presents the results of a 16-month cooperative study between the Department of Mining Engineering at SIUC and a local coal company.
A Paleoenvironmental Study Of The Salem Limestone In The Vicinity Of St. Louis, Missouri, Douglas J. Van Brunt
A Paleoenvironmental Study Of The Salem Limestone In The Vicinity Of St. Louis, Missouri, Douglas J. Van Brunt
Masters Theses
“The Salem Limestone (Meramecian) of Mississippian age in the vicinity of St. Louis, Missouri is composed of a variable sequence of limestones deposited in shallow waters adjacent to scattered positive elements. This unit varies in thickness from zero up to 160 feet.
A medium to coarse-grained calcarenite is the dominant rock-type of the thesis area and is most abundant in the central and southwest regions. Stratigraphic sections in the northern region are more dolomitic, increasingly brecciated, and contains numerous secondary features. The southeast region is thinly bedded and composed of greater amounts of micrite formed by algal activity or direct …
A Gravity And Magnetic Study Of The Crooked Creek Cryptoexplosion Structure, Crawford County, Missouri, Charles Edward Woodbury
A Gravity And Magnetic Study Of The Crooked Creek Cryptoexplosion Structure, Crawford County, Missouri, Charles Edward Woodbury
Masters Theses
"The pre-Pennsylvanian structure at Crooked Creek consists of a complex, vertically faulted ring of Cambrian and Ordovician sediments with a central uplifted core. The center of the structure is strongly deformed and contains shatter cones, brecciation, and other signs of extreme shock.
A magnetic low over the center of the structure suggests that igneous material was not involved in the formation of the structure, and this is corroborated by core analysis. Gravity data indicates several small gravity lows, possibly associated with areas of brecciation, circling the flanks of the structure. As in the magnetic data, there is no indication that …
Missouri S&T Magazine, April 1986, Miner Alumni Association
Missouri S&T Magazine, April 1986, Miner Alumni Association
Missouri S&T Magazine
No abstract provided.
A Case Of Singular Geotechnical Failure For Industrial Structures In The Peruvian Andes, A. Carillo Gil, R. Torres Vega
A Case Of Singular Geotechnical Failure For Industrial Structures In The Peruvian Andes, A. Carillo Gil, R. Torres Vega
International Conference on Case Histories in Geotechnical Engineering
During the rainy season of 1982, foundation distress was occurred at several recently completed and still incomplete structures of an important mine project located in the Peruvian Andes. When the tailings thickener was tested an unexpected settlement started, some cracking was observed in the slab, and the central pier settled and tilted. The nature of the distress suggested the failure occurred as the result of the combined effect of a long term seepage under the bearing foundation soil and due to its different degree of compaction. This paper presents the characteristics of these problems as both foundation and fill materials, …
Carrying Water To Newcastle, Lloyd Lore Wartes
Carrying Water To Newcastle, Lloyd Lore Wartes
UMR-MEC Conference on Energy / UMR-DNR Conference on Energy
Western coals, now being shipped by unit trains to eastern and southern markets, contain from 13% to 32% moisture. Drying of these coals at the mine would reduce the cost of coal to the utilities from 10% to 16% IF the railroads do not materially increase rates on higher BTU coal.
The spontaneous combustion of dry coal can be inhibited, and the savings per unit train should range from $1,375,000 to $4,129,000 per year according to the various minimum tonnage rates. The shipment of dried coal will reduce the tonnages being shipped by 15%, or increase the railroad carrying capacity …
Oil Shale Energy And The Environment, Stephen Utter
Oil Shale Energy And The Environment, Stephen Utter
UMR-MEC Conference on Energy / UMR-DNR Conference on Energy
Shale oil can be produced from oil shale by true In situ, modified in situ, and surface retorting methods. Both modified in situ and surface methods require mining of the oil shale. The environmental Implications of an oil shale mining industry are reviewed and the impacts upon land use, air and water quality, and ecological systems discussed. The Bureau's mining environmental research program is described and the results to date summarized.
Geology Of The Al-Khums Area Northwestern Libya With Emphasis On The Stratigraphy And Biostratigraphy Of The Al-Khums Formation, Mostafa Juma Salem
Geology Of The Al-Khums Area Northwestern Libya With Emphasis On The Stratigraphy And Biostratigraphy Of The Al-Khums Formation, Mostafa Juma Salem
Doctoral Dissertations
"The dissertation represents a geologic study of an area bordering the Mediterranean Sea in northwestern Libya. About 1200 km2 were mapped and 28 stratigraphic sections were prepared.
The bedrock consists of 16 stratigraphic units of Mesozoic and Cenozoic age having a combined maximum thickness of about 750 meters. The oldest unit exposed, the Abu Shaybah Formation, is a redbed sequence of Triassic and Jurassic age. These beds are unconformably separated from Cretaceous carbonates (Garian Limestone, Ain Tobi Formation, and Gezzar Dolomite). These units in turn are overlain by the Miocene Al-Khums Formation. Younger Quaternary units consist of nearshore marine …
The National Waste Terminal Storage Program, C. D. Zerby
The National Waste Terminal Storage Program, C. D. Zerby
UMR-MEC Conference on Energy / UMR-DNR Conference on Energy
The National Waste Terminal Storage (NWTS) program has been established to provide facilities (federal repositories) in various deep geologic formations at multiple locations in the USA which will safely dispose of the commercial radioactive waste that must be delivered to a federal repository for terminal storage. This paper presents an overview of the NWTS program and describes the stepwise approach that is being taken in meeting the objective of the program.
Classification Of Surficial Materials, James Hadley Williams
Classification Of Surficial Materials, James Hadley Williams
Doctoral Dissertations
"A surficial materials classification system has been designed to fit the needs of a geologist in mapping and classifying surficial materials. The system developed in this study is intended primarily for analysis of surficial materials where time-stratigraphic markers are not applicable or recognized. Primary classification is based on fabric and mode of origin supplemented by data on engineering and pedologic properties.
Several types of classification systems presently exist for use in soil investigations. Only three of these systems have found widespread acceptance, two serving the engineering profession and the other the needs of the soil scientist. These systems are not …
Tertiary Welded Tuffs Of The Ryan Spring Area, Needle Range, Beaver County, Utah, Peter Carlyle Rauch
Tertiary Welded Tuffs Of The Ryan Spring Area, Needle Range, Beaver County, Utah, Peter Carlyle Rauch
Masters Theses
"The Needle Range of southwestern Utah is composed of Paleozoic sediments overlain by a thick sequence of Tertiary volcanic rocks primarily of the welded tuff class. The area has undergone at least four stages of post-eruptive structural deformation. The most significant stage is that which formed the range by normal Basin and Range type faulting. The faults strike northwest and tilt the volcanic layers northeast.
The volcanic section is composed primarily of the Needles Range Formation (Oligocene) overlain by the Isom Formation and underlain by several flows and ash flows, one of which has been tentatively correlated to the Escalante …
An Investigation Of Combined Thermal Weakening And Mechanical Disintegration Of Hard Rock, George Bromley Clark, T. F. Lehnhoff, Vernon Dale Allen, Mahendrakumar Ramkrishna Patel
An Investigation Of Combined Thermal Weakening And Mechanical Disintegration Of Hard Rock, George Bromley Clark, T. F. Lehnhoff, Vernon Dale Allen, Mahendrakumar Ramkrishna Patel
Mining Engineering Faculty Research & Creative Works
"The research under modified Contract No. H0220068 has been devoted to experimental thermal-mechanical fragmentation of Missouri red granite in place, and to supporting theoretical analyses. The results of the previous year's experimental work showed that thermal stresses are several times more effective in fragmenting hard rock when they are created within the rock rather than upon the surface. Also, large blocks {4-foot cubes) are not adequate to simulate the response of in situ rock.
Based upon laboratory tests an experimental round was designed analogous to an explosive blasting round with coiled wire heating elements placed in drill holes. Three displacement …
Heavy Metal Analysis Of Stream Sediments In The James River Basin, Missouri, William J. Head
Heavy Metal Analysis Of Stream Sediments In The James River Basin, Missouri, William J. Head
Masters Theses
"A reconnaissance survey of stream sediments using the minus 80 mesh sieve fraction was made at 53 sites throughout the James River basin, Missouri. Sample sites within the 1460 square miles of the basin were chosen at tributary confluences, suspected contamination sources, and known areas of mineralization. Replicates and stream profiles were taken to check for analytical variation and reproducibility of results. Sediment samples were prepared by a hot nitric acid leach method. The sediments were analyzed using an atomic absorption unit to determine Cu, Pb, Zn, and Cd trace metal contents.
Values of selected streams within the basin were …
Stratigraphy, Genesis, And Economic Potential Of The Southern Part Of The Florida Land-Pebble Phosphate Field, Dean Stanley Clark
Stratigraphy, Genesis, And Economic Potential Of The Southern Part Of The Florida Land-Pebble Phosphate Field, Dean Stanley Clark
Doctoral Dissertations
"The important and highly productive Florida land-pebble phosphate field is located in west central peninsular Florida in portions of Hillsborough, Polk, Hardee, and Manatee counties. The Pine Level phosphate area, described in detail in this report, is south of the previously known and mined deposits and occurs in portions of Manatee, Sarasota, and De Soto counties. Results of the current geologic study of the Pine Level phosphate deposit and the evaluation of the overall potential of this southern part of the land-pebble field are presented.
The entire southern part of the phosphate field is underlain by more than 15,000 feet …
The Mio-Eugeosynclinal Thrust Interface And Related Petroleum Implications In The Sason-Baykan Area, Southeast Turkey, Ismail Özkaya
The Mio-Eugeosynclinal Thrust Interface And Related Petroleum Implications In The Sason-Baykan Area, Southeast Turkey, Ismail Özkaya
Doctoral Dissertations
"A detailed investigation of the stratigraphy, structure and petroleum geology of the Sason-Baykan region in 600 square km area of the thrust belt of southeast Turkey was completed at a scale 1: 25 000. Geosynclinal sediments within the area were redated.
Results of field study indicate a massive plate of metamorphic rocks and crystalline limestones was thrust southward over geosynclinals sediments. These in turn were thrust over the southern marginal basin deposits. A stratigraphic sequence of the allochthonous geosynclinals sediments was reconstructed and correlated with the autochthonous Tertiary section. Contrary to earlier views the allochthonous sediments and accompanying igneous rocks …
Digital Registration Of Stereo Images Using The Fast Fourier Transform, Victor Francis Wilreker Jr.
Digital Registration Of Stereo Images Using The Fast Fourier Transform, Victor Francis Wilreker Jr.
Masters Theses
"The exact alignment of multispectral imagery is a requirement of any image classification system. This investigation develops a system of programs which result in a technique that corrects for the translational and rotational misalignment of two images. Rotational and translational components are determined by using the fast Fourier transform to find the points of maximum correlation between the two images. The registration of two equal but misaligned boxes is given as an example of how the transform technique is used in correlating the images. The results of registering two digitized images that were obtained by scanning a pair of color …
Arctic Marine Terminals -- Some Environmental And Engineering Considerations, Robert L. Mccollom Jr., William W. Moore
Arctic Marine Terminals -- Some Environmental And Engineering Considerations, Robert L. Mccollom Jr., William W. Moore
UMR Journal -- V. H. McNutt Colloquium Series
Studies are presently underway to determine the technical and economic feasibility of various Arctic marine transportation systems, including ice-breaker super-tankers and submarine tankers. An important consideration in these studies is the design and construction of marine terminal facilities which will be suited to the unique problems of the Arctic. Factors which will significantly affect the design of proposed marine terminals include:
1) bathymetric configuration of the continental shelf;
2) influence of moving pack ice on artificial structures, both at the air-water interface and along the bottom;
3) lateral and vertical variations in soil conditions, including residual permafrost, which might adversely …
Ground Water Of The Uncompahgre Valley Montrose County, Colorado, Ted William Craig
Ground Water Of The Uncompahgre Valley Montrose County, Colorado, Ted William Craig
Masters Theses
"Data from water quality tests of 50 wells and from general well information of 309 wells registered with the Colorado Division of Water Resources are presented for the area of Montrose County, Colorado, drained by the Uncompahgre River. This information, along with other pertinent information such as water laws and costs, is evaluated to determine the feasibility of increasing the use of ground water in the area. The drainage basin of the Uncompahgre River within the Montrose area bas three main geologic structures: the Uncompahgre uplift, the Montrose syncline, and the Gunnison uplift. All formations exposed in the area are …
The Rollamo 1970, University Of Missouri - Rolla
A Subsurface Geologic Study Of Petroleum Possibilities In The Pennsylvanian Rocks Of Concho County, Texas, Gregory Paul Kraus
A Subsurface Geologic Study Of Petroleum Possibilities In The Pennsylvanian Rocks Of Concho County, Texas, Gregory Paul Kraus
Masters Theses
"During early Pennsylvanian time the area now occupied by Concho County was a portion of the Texas peninsula, a broad, low arch with a karst topography developing on its exposed Ellenburger surface. A mid-Pennsylvanian marine transgression inundated the arch and it became an area of clear, shallow water deposition favorable to limestone development. Local sedimentation during Strawn time was largely controlled by its position relative to the Llano uplift and surrounding basins. A variety of subsurface maps were constructed for this study essentially utilizing electric log data. The results indicate that limestones of the Strawn platform facies rapidly change in …
Geology Of The Acari Iron Mining District Arequipa, Peru, Raul Alejandro Zevallos
Geology Of The Acari Iron Mining District Arequipa, Peru, Raul Alejandro Zevallos
Masters Theses
"The Acari Iron Mining District, part of a tilted uplifted fault block, comprises an area about 300 square kilometers, in the southern part of the coastal belt of Peru. It is in the foothills of the western range of the Andes and it is dominantly formed by granodioritic and granitic intrusive rocks which belong to the Andean batholith of Cretaceous-Tertiary age. The intrusive rocks are overlain by a central, elongated, northwest trending band, of metasedimentary and volcanic rocks
The magnetite deposits of Acari district are long, dike-shaped bodies, which fill two systems of fractures in the granodiorite intrusive, located in …
Petrology And Mineralogy Of The "Old Workings Area," El Salvador, Chile, Bertis James Vander Schaaff
Petrology And Mineralogy Of The "Old Workings Area," El Salvador, Chile, Bertis James Vander Schaaff
Masters Theses
"The 'Old Workings Area,' so called for its early mining by the Incas, is located 4 1/2 miles northeast of the El Salvador Porphyry copper deposit, the third largest copper producer in Chile. The area mapped in this study is shown to consist of rhyolite pebble conglomerate, two volcanic flows, andesite and rhyolite porphyry, and two intrusions. Quartz porphyry and tourmaline-bearing breccia. Petrographic study of surface and drill core rock samples confirms the field nomenclature used for the five rock types. All of the rock types are altered, but the quartz porphyry and andesite are the most intensely altered. Both …