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Page 6393, results 159801 - 159825

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Publication Extents

Not all publications have extents, not all extents are completely accurate
The water resources of southeast Iowa
R. W. Coble, J.V. Roberts
1971, Iowa Geological Survey Water Atlas 4
Water is vital in the lives of the people and the economy of any area.  In order to utilize this natural resource in the most efficient and beneficial manner, a basic knowledge and understanding of its sources and the occurrence and potential of each source must be gained.  To provide...
Chemical compositions of rock types as factors in our environment
Harry A. Tourtelot
Helen L. Cannon, Howard C. Hopps, editor(s)
1971, Book chapter, Environmental geochemistry in health and disease
The types of rocks that form geologic units in the Earth’s crust supply most of the raw materials from which soils are formed and from which water derives its inorganic constituents. The compositions of what we eat and drink thus depend in part upon the compositions of the source rocks.Igneous...
Remanent magnetization and susceptibility of late Cenozoic rocks from New Zealand
Allan Cox
1971, New Zealand Journal of Geology and Geophysics (14) 192-207
Measurements of magnetic remanence and susceptibility were made on 176 samples of volcanic rocks from 22 late Cenozoic formations from the North Island. Intensities of remanence, susceptibilities, and Q ratios are highly variable in both the ignimbrites and andesites and their ranges overlap, indicating that the magnetic...
Magnetic susceptibility and triangular exchange coupling in the tourmaline mineral group
T. Tsang, A. N. Thorpe, G. Donnay, Frank E. Senftle
1971, Journal of Physics and Chemistry of Solids (32) 1441-1448
Magnetic susceptibilities of three iron-rich tourmaline crystals from Mexquitic (Mexico), Pierpont (New York), and Madagascar with different and known chemical compositions have been studied from 8° to 300°K. The iron atoms in the tourmaline crystal structure, space group R3m, a∼15·9, c∼7·2 , are...
Palaeomagnetism and potassium-argon ages of volcanic rocks of Ngorongoro caldera, Tanzania
C. S. Grommé, T. A. Reilly, A. E. Mussett, R. L. Hay
1971, Geophysical Journal International (22) 101-115
Natural remanent magnetization (NRM) has been measured in 21 lava flows and 1 tuff in the south-west wall of Ngorongoro caldera, Tanzania. The lowest three lavas are normally magnetized, the next two have intermediate directions, and the remainder are reversed; potassium-argon dating places the reversal at 2.45 My, corresponding...
Wells and springs in California and Nevada within 100 miles of point 37°15' N, 116°25' W, on Nevada test site
William Thordarson, B.P. Robinson
1971, Report
Studies of published and unpublished geologic and ground-water data, for an inventory of 6,032 wells and 754 springs in parts of Inyo and Mono Counties, California, and Clark, Esmeralda, Lincoln, and Nye Counties, Nevada, reveal the following information:A complex sequence of granitic, metamorphic, volcanic, and sedimentary rocks of Precambrian to...
Water resources of the Coamo area, Puerto Rico
Ennio V. Giusti
1971, Report
This study, like other similar studies, was made possible by a cooperative water-resources program between the U.S. Geological Survey and the Puerto Rico Water Resources Authority (at the time), representing also the Puerto Rico Aqueduct & Sewer Authority and the Puerto Rico Industrial Development Company.This report covers the hydrologic investigation...
Open-channel integrating-type flow meter
K.C. Koopman
1971, Report
A relatively inexpensive meter for measuring cumulative flow in open channels with a rated control,. called a "totalizer", was developed. It translates the nonlinear function of gage height to flow by use of a cam and a float. A variable resistance element in an electronic circuit is controlled by the...
Application of remote sensing techniques for appraising changes in wildlife habitat
Harvey K. Nelson, Albert T. Klett, John E. Johnston
1971, Conference Paper, International Workshop in Earth Resources Survey Systems
An attempt was made to investigate the potential of airborne, multispectral, line scanner data acquisition and computer-implemented automatic recognition techniques for providing useful information about waterfowl breeding habitat in North Dakota. The spectral characteristics of the components of a landscape containing waterfowl habitat can be detected with airborne scanners. By...
Biology of larval sea lampreys (Petromyzon marinus) of the 1960 year class, isolated in the Big Garlic River, Michigan, 1960-65
Patrick J. Manion, Alberton L. McLain
1971, Technical Report 16
The early life history of the sea lamprey, from hatching to the first capture of metamorphosed individuals, is described from observations on a known-age population isolated in a tributary of southern Lake Superior. The population had its origin in the spring of 1960, when 722 sea lampreys nearing spawning condition...
Limnological data from Lake St. Clair, 1963 and 1965
Jarl K. Hiltunen
1971, Data Report 54
Data, primarily benthological, are given for collections made at 14 stations. Included are records of water transparency, water temperature, water samples for chemical analysis, and bottom samples for the analysis of the macrobenthos....
Salmonid viruses: Infectious pancreatic necrosis virus
K. Wolf, M. C. Quimby
1971, Archiv Fur Die Gesamte Virusforschung (34) 144-156
Epizootics occurred among young trout in France, and the behavior and symptoms suggested infectious pancreatic necrosis (IPN) virus. Specimens preserved in glycerol were sent to the U.S.A. for virological examination. Virus was isolated from four of five lots, but neutralization with antiserum against ATCC VR299 strain IPN virus was incomplete....
The determination of vanadium in brines by atomic absorption spectroscopy
Hans J. Crump-Wiesner, H.R. Feltz, W.C. Purdy
1971, Analytica Chimica Acta (55) 29-36
A standard addition method is described for the determination of vanadium in brines by atomic absorption spectroscopy with a nitrous oxide-acetylene flame. Sample pH is adjusted to 1.0 with concentrated hydrochloric acid and the vanadium is directly extracted with 5% cupferron in methyl isobutyl ketone...
Variation of iridium in a differentiated tholeiitic dolerite
L. P. Greenland
1971, Geochimica et Cosmochimica Acta (35) 319-322
Iridium has been determined in a drill core from the Great Lake (Tasmania) dolerite sheet. Iridium decreases systematically from the mafic dolerites (0.25 ppb) to the granophyres (0.006 ppb). The trend with differentiation closely parallels that of chromium....
Scanning electron microscopy of clays and clay minerals
B.F. Bohor, R.E. Hughes
1971, Clays and Clay Minerals (19) 49-54
The scanning electron microscope (SEM) proves to be ideally suited for studying the configuration, texture, and fabric of clay samples. Growth mechanics of crystalline units—interpenetration and interlocking of crystallites, crystal habits, twinning, helical growth, and topotaxis—also are uniquely revealed by the SEM.Authigenic kaolins make up the bulk of the examples...