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Articles 1501 - 1530 of 1545
Full-Text Articles in Earth Sciences
Influence Of Las Vegas Wash Density Current On Nutrient Availability And Phytoplankton Growth In Lake Mead, John R. Baker, Larry J. Paulson
Influence Of Las Vegas Wash Density Current On Nutrient Availability And Phytoplankton Growth In Lake Mead, John R. Baker, Larry J. Paulson
Publications (WR)
Density currents are commonly formed in reservoirs because of temperature or salinity induced density differences between inflowing and receiving waters. Anderson and Pritchard (1951) were among the first to demonstrate this in their investigations of density currents in Lake Mead. They found that the Colorado River formed an underflow in Lake Mead during the winter, an overflow in the spring and an interflow in the summer and fall. Wunderlich and Elder (1973) have since described the hydromechanics of these types of flow patterns, and density currents have been reported for several other large reservoirs (Carmack et al. 1979, Johnson and …
Chemistry Of The Spring Waters Of The Ouachita Mountains Excluding Hot Springs, Arkansas, George H. Wagner, Kenneth F. Steele
Chemistry Of The Spring Waters Of The Ouachita Mountains Excluding Hot Springs, Arkansas, George H. Wagner, Kenneth F. Steele
Arkansas Water Resources Center Technical Reports
This report is based on the chemical analysis of the waters from 93 springs and 9 wells. Springs, when free from metal plumbing, provide an uncontaminated source of the ground water and it was desired to obtain water uncontaminated with metals. A few wells were added to the list, usually because of their unique location in the sampling grid.
A Statistical Analysis Of The Quality Of Surface Water In Nebraska, R. A. Engberg
A Statistical Analysis Of The Quality Of Surface Water In Nebraska, R. A. Engberg
United States Geological Survey: Publications
This report provides descriptive statistics for 29 chemical or biological constituents for 109 stream sites in Nebraska sampled by the U.S. Geological Survey beginning in 1946. Also provided for each site are regression equations relating specific conductance to each of 12 chemical constituents and a regression equation relating specific conductance to stream discharge. The descriptive statistics are presented by river basins. Water leaving these basins that has the lowest mean specific conductance (266 umho/cm) is from the Niobrara River at Verdel, and water that has the highest (1,890 umho/cm) is from the South Platte River at Roscoe. Statewide, the principal …
Saratoga: The Bubbles Of Reputation And Their Implications For An Embryonic Rift System In The Upper Hudson River Valley, James R. Young
Saratoga: The Bubbles Of Reputation And Their Implications For An Embryonic Rift System In The Upper Hudson River Valley, James R. Young
Geology Theses and Dissertations
Carbonated, alkaline, saline waters occur over a wide area in the upper Hudson River Valley approaching 1,000 square miles. Through the sampling (spring and fall) of 39 locations, half of which were hitherto unsampled, the waters are shown to be a complexly mixed system with at least five major components.
They are:
1) a gaseous phase consisting primarily of CO2;
2) a fluid (containing the dissolved CO2) possibly analogous to a metamorphic brine whose major chemistry is HCO3>Na>Cl;
3) formational waters of variably low salinities which may be the end products of progressive dilution of Paleozoic connate brines …
"Energy Resources", Harrison Scott Brown
"Energy Resources", Harrison Scott Brown
Special Collections: Oregon Public Speakers
With: Salter, C. L. The urban enigma.
The Geology And Geochemistry Of The North Fork Stock, Northeastern Oregon, David Joseph Matty
The Geology And Geochemistry Of The North Fork Stock, Northeastern Oregon, David Joseph Matty
Dissertations and Theses
The North Fork stock is a composite intrusive body of Late Jurassic-Early Cretaceous age which outcrops in the Blue Mountains of northeastern Oregon. The upper 600 m of the intrusion are exposed over an area of approximately 36 km2 along the canyon walls of the North Fork of the John Day River in Grant and Umatilla counties. The stock intrudes metasediments, metavolcanics, and metagabbros associated with the Permian-Triassic Elkhorn Ridge Argillite. Contact metamorphism of the Elkhorn Ridge Argillite is developed to the hornblende-hornfels facies throughout most of the exposed area of this unit in the study area. The contact …
Petrology And Mineral Chemistry Of Some Jan Mayen Volcanics, Carla A. White
Petrology And Mineral Chemistry Of Some Jan Mayen Volcanics, Carla A. White
Geology Theses and Dissertations
The island of Jan Mayen is the northernmost active volcano on the Mid-Atlantic Ridge. The rocks of Jan Mayen belong to the potassic series of the alkaline rocks and appear to belong to the straddle type association. The ankaramites and alkali olivine basalts are characterized by the presence of large xenocrysts of rimmed chromium diopside, titaniferous salite, olivine (Fo83 to Fo88), magnetite and sometimes plagioclase (bytownite rimmed by labradorite). Phenocrysts of olivine (Fo74) and plagioclase (andesine) are present in several rocks. These and phenocrysts lie in a matrix composed of` titaniferous salite, olivine (Fo58), plagioclase (andesine), magnetite, biotite and sometimes …
Alkalinity And Ph In The Southern Chesapeake Bay And The James River Estuary, George T. F. Wong
Alkalinity And Ph In The Southern Chesapeake Bay And The James River Estuary, George T. F. Wong
OES Faculty Publications
The ranges of alkalinity and pH in the southern Chesapeake Bay and the James River estuary were 2.25 meq·liter−1 at 32‰ to
The Distribution Of Several Metals And Cation Exchange Capacity In Sediment Fractions From An Artificial And Natural Marsh, James River, Virginia, William Nivens
OES Theses and Dissertations
In order to examine the mechanisms by which Fe, Mn, Ca, Zn, Cu, Ni and Pb are bound in sediments, a sequential selective extraction procedure was employed on sediment samples collected at an experimental dredge disposal marsh and a neighboring natural marsh located near Windmill Point, James River, Va. The metal concentrations were determined in six phases, interstitial water, exchangeable, easily reducible (oxides of Mn), organic, moderately, reducible (oxides of Fe), and residual fractions. In addition, the cation exchange capacity (CEC) of the sediments was determined as well as the actual role of organics and colloidal iron coatings as they …
Geochemistry Of A Carbonatite In Montgomery County, Arkansas, George H. Wagner, Ronald H. Konig, Michael D. Jones
Geochemistry Of A Carbonatite In Montgomery County, Arkansas, George H. Wagner, Ronald H. Konig, Michael D. Jones
Journal of the Arkansas Academy of Science
No abstract provided.
Sediment Interstitial Dissolved Mercury And Carbon Relationships In An Artificial And Natural Marsh, James River, Virginia, Apostolos Katsaounis
Sediment Interstitial Dissolved Mercury And Carbon Relationships In An Artificial And Natural Marsh, James River, Virginia, Apostolos Katsaounis
OES Theses and Dissertations
Thirty six sediment cores were collected during August, 1976 and January, 1977 in order to examine the relationships between dissolved organic carbon and total dissolved mercury in the interstitial water of two marshes located near Windmill Point, James River, 16 km downstream from Hopewell, Virginia. The Windmill Point marsh development site is a dredged material disposal island in the James River. The reference marsh which does not contain dredged material, is located 2.3 km upstream at Ducking Stool Point.
The concentrations of dissolved organic carbon and total dissolved mercury showed no significant difference between the two marshes. Trends in the …
Petrology Of The Oceanographer Fracture Zone (35ºn35ºw), Tsugio Shibata
Petrology Of The Oceanographer Fracture Zone (35ºn35ºw), Tsugio Shibata
Geology Theses and Dissertations
During a geological and geophysical survey of the Oceanographer Fracture Zone (35°N, 35°W), seventeen dredge hauls containing a variety of rocks were obtained. Petrographic study shows that these rock samples can be classified into six main rock types: fresh basalt, weathered basalt, metabasalt, gabbro, metagabbro, and serpentinite. Most of the dredge hauls were positioned on the steep, southern wall of the fracture zone, and an inference from the dredging results suggests that basalt is the most abundant rock type which outcrops at the junction between the rift valley and the fracture zone; however, as we move away from the junction, …
Processes Controlling The Distribution Of Methane In The Cariaco Tranch, Venezuela, Denis A. Wiesenburg
Processes Controlling The Distribution Of Methane In The Cariaco Tranch, Venezuela, Denis A. Wiesenburg
OES Theses and Dissertations
Abstract unavailable.
The Analysis Of Volatile Organic Compounds In The Southern Chesapeake Bay, Virginia By Gas Chromatography/Mass Spectrometry, James D. Haluska
The Analysis Of Volatile Organic Compounds In The Southern Chesapeake Bay, Virginia By Gas Chromatography/Mass Spectrometry, James D. Haluska
OES Theses and Dissertations
Sea-water samples from the Norfolk, Virginia area were analyzed for trace volatile organic compounds by helium sparging. Contents of the trap were injected into a gas chromatograph/mass spectrometer. Analysis of the trap contents indicated the presence of aliphatic and olef1nic hydrocarbons containing up to six carbon atoms and eight halogenated compounds of up to two carbon atoms in length. The halogenated compounds which were identified were dichlorofluoromethane, trichlorotrifluoroethane, carbon tetrachloride, chloroform, trichloroethane (2 isomers) bromodichloromethane, and chlorotrifluoroethylene. The
relative concentrations of volatile organic compounds generally tended to increase in samples collected from water prone to urban environmental pressures. All eight …
Maine Gems And Gem Minerals, Maine State Museum
Maine Gems And Gem Minerals, Maine State Museum
Maine Collection
Maine Gems and Gem Minerals
The Maine State Museum - Printed under Appropriation No. 1741.1
Sections Include : "An Introduction to the Gemstones of Maine", "Tourmaline", "Beryl", "Quartz Family Gems", "Topaz", "Gold", "Miscellaneous Gem Varieties", "Maine's 'Lost' Gem Mines", "Hamlin Necklace", etc
A Geochemical Study Of A Marsh Environment, Thomas F. Lytle, Julia Sever Lytle, Patrick L. Parker
A Geochemical Study Of A Marsh Environment, Thomas F. Lytle, Julia Sever Lytle, Patrick L. Parker
Gulf and Caribbean Research
The goal of this study was twofold: 1) chemically to characterize a specific salt marsh, the sediments and associated biota and 2) to establish clear relationships between the chemical substances residing in the sediments and similar or identical substances occurring in the biological specimens. In this particular study it was felt that the hydrocarbons would yield the most significant organic geochemical information. These compounds are ubiquitous but minor components of all organisms. Though their function is not entirely understood, it is known that they are concentrated in the waxy coatings of plants and most likely aid in the protective mechanisms …
The Geology Of The Pittsburg Landing Area, Snake River Canyon, Oregon-Idaho, David L. White
The Geology Of The Pittsburg Landing Area, Snake River Canyon, Oregon-Idaho, David L. White
All-Inclusive List of Electronic Theses and Dissertations
The major purpose of the study was to map, describe, and correlate the pre-Tertiary rocks. Accessible and excellent exposures at Pittsburg Landing enabled the writer to make a somewhat detailed study of the stratigraphy. The thesis area also offered an opportunity to study in a reconnaissance manner, the Tertiary Columbia River Basalt as described by Waters, and more recently y Ozier.
Determination Of Nutrient Levels And Proposed Predictive Models For Phosphate In The Lafayette River, Norfolk, Virginia, John R. Montgomery
Determination Of Nutrient Levels And Proposed Predictive Models For Phosphate In The Lafayette River, Norfolk, Virginia, John R. Montgomery
OES Theses and Dissertations
The Lafayette River, an Urban, well-mixed estuarine embayment, was sampled from October, 1970 to January, 1972 for phosphate, nitrate, nitrite, oxygen, water temperature and salinity. The mean values found for these samples were: oxygen saturation from 69% to 106% nitrate from 0 to 4 microgram-atoms per liter, and salinity from 13 ‰ to 24 ‰. The mouth of the Elizabeth River to Hampton Roads as also sampled from May, 1971 to August, 1971. The Lafayette and Elizabeth Rivers were also sampled over a 24 hour period in the summer of 1971 and the Lafayette River again in the winter of …
Catechol Effected Dissolution Of Silicate Minerals, James Maurice Kelley
Catechol Effected Dissolution Of Silicate Minerals, James Maurice Kelley
Dissertations and Theses
The chemical properties of guanidinium tris(catecholato)siliconate, [(H₂N)₂C=NH₂]₂[Si(C₆H₄O₂)₃]·XH₂O (0 < X < 1), precipitated from an ammoniacal solution of silica and catechol by adding guanidinium hydrochloride, (H₂N)₂C=NH·HC1, were studied, and infrared, nmr, x-ray powder diffraction, and analytical data were gathered.
This same compound was, upon addition of' (H₂N)₂C=NH·HC1, isolated from 0.25, M aqueous catechol solutions buffered at pH 10 and containing the silicate minerals albite, andradite, muscovite, pyrophyllite, talc, and wollastonite, and also from unbuffered catechol solutions containing wollastonite and andradite.
It is concluded from this work that the formation of an anionic catechol-silicon complex, Si(C₆H₄O₂)₃²⁻, is largely responsible for the dissolution of the minerals mentioned above. From this conclusion, it is proposed that naturally occurring members of the class of organic compounds to which catechol belongs, the aromatic v̲i̲̲c̲-diols, may play …
History Of Sedimentation In Montsweag Bay, Detmar Schnitker
History Of Sedimentation In Montsweag Bay, Detmar Schnitker
Maine Collection
History of Sedimentation In Montsweag Bay
by Setmar Schnitker
Bulletin #25, Department of Forestry, Augusta, Maine, 1972.
Contents: Abstract / Introduction / Geographic Setting / Seismic Profiling / Pleistocene Sediments / Holocene Sediments / Actual Sedimentation /. Suspended Sediments / Recent Changes / Outlook / Acknowledgements / References
Petrology Of The Nemeiben Lake Ultramafic And Associated Nickel-Sulphide Deposits, Anantaramam Peddada
Petrology Of The Nemeiben Lake Ultramafic And Associated Nickel-Sulphide Deposits, Anantaramam Peddada
Geology Theses and Dissertations
The Nemeiben Lake ultramafic body is located in the center of Saskatchewan, Canada, within the Churchill Province of the Canadian Shield. The ultramafic rocks consist of serpentinites, partly serpentinized and uralitized pyroxenite, and unaltered pyroxenite. Associated sulphide mineralization is of disseminated, net texture, and fracture filling types. The ore minerals present are pyrrhotite, pentlandite, chalcopyrite, pyrite, marcasite, violarite, bravoite and native copper. The sulphides are considered to be initially of magmatic origin formed from a sulphide melt separated at a late stage during crystallization of the ultramafic rocks. Subsequent serpentinization has locally redistributed the ores.
Serpentinization in the Nemeiben Lake …
An Evaluation Of A Stable Isotope Of Dysprosium For Labeling And Tracing Sedimentary Particles, Charles Glenn Boone
An Evaluation Of A Stable Isotope Of Dysprosium For Labeling And Tracing Sedimentary Particles, Charles Glenn Boone
OES Theses and Dissertations
An evaluation of the application of dysprosium oxide as a tracer coating to surface label sedimentary particles is made. Physical and chemical properties of the labeled sand are studied. Effective diameters and settling properties of the tracer sand are compared with unlabeled sand. A total of 8.51 kg of labeled sand was placed on the beach at Camp Pendleton. Dispersal patterns obtained 1 and 4 hours after tracer injection indicate a general down current mean tracer migration rate of 0.21 cm/sec (0.42ft/sec). An absolute detection limit of 4 or 5 parts per 100,000 and a real detection limit, after field …
Geology Of The Moose River And Roach River Synclinoria, Northwestern Maine, Arthur J. Boucot, Edward W. Heath
Geology Of The Moose River And Roach River Synclinoria, Northwestern Maine, Arthur J. Boucot, Edward W. Heath
Maine Collection
Geology of the Moose River and Roach River Synclinoria, Northwestern Maine
by Arthur J. Boucot, with contributions by Edward W. Heath
Bulletin No.21, Maine Geological Survey
Department of Economic Development, Augusta, Maine (August, 1969).
Contents: Abstract / Introduction / Stratigraphy / Intrusive Rocks / Metamorphism / Structure / Large Scale Maps / Somerset Island / Lobster Island / Historical Geology / The Problem of Shell Beds / References / Appendix I /
Solution Geochemistry Of The Water Of Limestone Terrains, John Thrailkill, David B. Beiter, Michael T. Osolnik, Roger H. Postley, William T. Mitchell, Leonard N. Plummer, James R. Riddell, Richard C. Worley, Robert D. Zwicker
Solution Geochemistry Of The Water Of Limestone Terrains, John Thrailkill, David B. Beiter, Michael T. Osolnik, Roger H. Postley, William T. Mitchell, Leonard N. Plummer, James R. Riddell, Richard C. Worley, Robert D. Zwicker
KWRRI Research Reports
Limestone groundwater flows mainly in openings it has solutionally enlarged, thus an understanding of the water's state of saturation relative to calcite (the principal mineral component of limestone) is fundamental to an understanding of the nature and evolution of the limestone aquifer. This study investigated the Mammoth Cave-Sinkhole Plain (MCSP) and Cave Hollow (CH) aquifers in Kentucky, both in Missippian limestones.
Both aquifers were always undersaturated with calcite. Except for completely ventilated vadose flows (usually) and some vadose seepage (occasionally), all recharges sampled (sinking streams, vadose flows, and vadose seepage) were also undersaturated. The lack of saturation in the MCSP …
Paleotectonic Investigations Of The Permian System In The United States, Edwin D. Mckee, Stephen S. Oriel, Henry L. Berryhill, Eleanor J. Crosby, Donald A. Myers, George H. Dixon, Marjorie E. Maclachlan, Melville R. Mudge, Edwin K. Maughan, Richard P. Sheldon, Earl R. Cressman, Thomas M. Cheney, Walter E. Hallgarth, Keith B. Ketner
Paleotectonic Investigations Of The Permian System In The United States, Edwin D. Mckee, Stephen S. Oriel, Henry L. Berryhill, Eleanor J. Crosby, Donald A. Myers, George H. Dixon, Marjorie E. Maclachlan, Melville R. Mudge, Edwin K. Maughan, Richard P. Sheldon, Earl R. Cressman, Thomas M. Cheney, Walter E. Hallgarth, Keith B. Ketner
United States Geological Survey: Publications
(A) Allegheny region, by Henry L. Berryhill, Jr
(B) Gulf Coast region, by Eleanor J. Crosby
(C) West Texas Permian basin region, by Steven S. Oriel, Donald A. Myers, and Eleanor J. Crosby
(D) Northeastern New Mexico and Texas-Oklahoma Panhandles, by George H. Dixon
(E) Oklahoma, by Marjorie E. MacLachlan
(F) Central Midcontinent region, by Melville R. Mudge
(G) Eastern Wyoming, eastern Montana, and the Dakotas, by Edwin K. Maughan
(H) Middle Rocky Mountains and northeastern Great Basin, by Richard P. Sheldon, Earl R. Cressman, Thomas M. Cheney, and Vincent E. McKelvey
(I) Western Colorado, southern Utah, and northwestern New …
Roughness Characteristics Of Natural Channels, Harry H. Barnes Jr.
Roughness Characteristics Of Natural Channels, Harry H. Barnes Jr.
United States Geological Survey: Publications
Color photographs and descriptive data are presented for 50 stream channels for which roughness coefficients have been determined. All hydraulic computations involving flow in open channels require an evaluation of the roughness characteristics of the channel. In the absence of a satisfactory quantitative procedure this evaluation remains chiefly an art. The ability to evaluate roughness coefficients must be developed through experience. One means of gaining this experience is by examining and becoming acquainted with the appearance of some typical channels whose roughness coefficients are known. The photographs and data contained in this report represent a wide range of channel conditions. …
Water Chemistry Survey Of Boulder Basin, Lake Mead, P. R. Tramutt, Bureau Of Reclamation
Water Chemistry Survey Of Boulder Basin, Lake Mead, P. R. Tramutt, Bureau Of Reclamation
Publications (WR)
The survey results indicate that the impoundment of water behind Hoover Dam has not adversely affected the dissolved oxygen (DO) content and that water quality and DO content were uniform regardless of depth. The study made in April-May 1964 will provide water quality data of Lake Mead prior to releases from Lake Powell as a basis for evaluating Lake Powell's effect on water quality and limnology of Lake Mead. The performance of a DO analyzer was tested and found unsatisfactory at depths below 150 ft. Parameters tested by standard chemical analyses of water samples in the Denver Laboratory and by …
A Detailed Economic Investigation Of Geochemical And Aeromagnetic Anomalies North Central Maine, W. F. Stickney, R. S. Young, L. A. Wing
A Detailed Economic Investigation Of Geochemical And Aeromagnetic Anomalies North Central Maine, W. F. Stickney, R. S. Young, L. A. Wing
Maine Collection
A Detailed Economic Investigation of Geochemical and Aeromagnetic Anomalies North Central Maine
W.F.Stickney, R.S.Young and L.A.Wing
Special Economic Series No.4, Maine Geological Survey, Department of Economic Development, Augusta, Maine (March 1965).
Contents: Foreword / Part I - Geology (W.F. Stickney) / Part II - Geophysics (R.S. Young) / Part III - Geochemistry (L.A. Wing) / References
Odor Report (1961), Walter A. Lawrance
Geologic And Ground-Water Reconnaissance Of The Loup River Drainage Basin Nebraska, R. T. Sniegocki, R. H. Langford
Geologic And Ground-Water Reconnaissance Of The Loup River Drainage Basin Nebraska, R. T. Sniegocki, R. H. Langford
United States Geological Survey: Publications
The Loup River and its tributaries drain an area of about 15,230 square miles in central Nebraska. The upper three-fifths of the drainage basin is in the Sand Hills region of Nebraska, and the lower two-fifths is in the loess plains and hills region. An eastward-thinning wedge of semiconsolidated and unconsolidated deposits of Tertiary and Quaternary age underlies the surficial dune sand and loess. These deposits, which are recharged by infiltrating precipitation, contain a tremendous volume of water at least 400 million acre-feet and annually discharge about 1.7 million acre-feet into streams. Although wells supply nearly all the water used …