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Page 6561, results 164001 - 164025

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Geomagnetic polarity zones for icelandic lavas
P. Dagley, R.L. Wilson, J. M. Ade-Hall, G.P.L. Walker, S.E. Haggerty, T. Sigurgeirsson, N.D. Watkins, P.J. Smith, J. Edwards, R.L. Grasty
1967, Nature (216) 25-29
Analysis of cores collected from a sequence of lavas in Eastern Iceland has made possible an accurate calculation of the average rate of reversal of the Earth's magnetic field....
The fractionation of nickel between olivine and augite as a geothermometer
T.A. Hakli, T. L. Wright
1967, Geochimica et Cosmochimica Acta (31) 877-884
The coexisting olivine, clinopyroxene and glass of five samples collected from the Makaopuhi lava lake in Hawaii, at temperatures ranging from 1050 to 1160°C were analysed for nickel with an electron probe microanalyser. The results strongly suggest that the distribution of nickel between these three phase pairs well obeys the...
Geomagnetic polarity epochs: new data from Olduvai Gorge, Tanganyika
C. S. Grommé, R. L. Hay
1967, Earth and Planetary Science Letters (2) 111-115
The lower lava flow of Bed I in Olduvai Gorge, Tanganyika, carries natural remanent magnetization (NRM) having normal polarity. Thermal demagnetization experiments demonstrate the stability of this NRM. Thus the Olduvai geomagnetic polarity event, which was originally named from the upper lava...
Cohenite: Its occurrence and a proposed origin
R. Brett
1967, Geochimica et Cosmochimica Acta (31) 143-159
Cohenite is found almost exclusively in meteorites containing from 6 to 8 wt.% Ni. On the basis of phase diagrams and kinetic data it is proposed that cohenite cannot form in meteorites having more than 8 wt.% Ni and that any cohenite which formed in meteorites having Ni content lower...
Loss of halogens from crystallized and glassy silicic volcanic rocks
D. C. Noble, V. C. Smith, L. C. Peck
1967, Geochimica et Cosmochimica Acta (31) 215-223
One hundred and sixty-four F and Cl analyses of silicic welded tuffs and lavas and glass separates are presented. Comparison of the F and Cl contents of crystallized rocks with those of nonhydrated glass and hydrated glassy rocks from the same rock units shows that most of the halogens originally...
Borate mineral assemblages in the system Na2O-CaO-MgO-B2O3-H2O
C. L. Christ, A.H. Truesdell, Richard C. Erd
1967, Geochimica et Cosmochimica Acta (31) 313-337
The significant known hydrated borate mineral assemblages (principally of the western United States) in the system Na2O-CaO-MgO-B2O3-H2O are expressible in three ternary composition diagrams. Phase rule interpretation of the diagrams is consistent with observation, if the activity of H2O is generally considered to be determined by the geologic environment. The...
Complexometric determination of gallium with calcein blue as indicator
H.N. Elsheimer
1967, Talanta (14) 97-102
A metalfluorechromic indicator, Calcein Blue, has been used for the back-titration of milligram amounts of EDTA in presence of gallium complexes. The indicator was used in conjunction with an ultraviolet titration assembly equipped with a cadmium sulphide detector cell and a microammeter for enhanced end-point detection....
Infection of the walleye, Stizostedion v. vitreum, of western Lake Erie with Bothriocephalus cuspidatus (Cooper)
David R. Wolfert, Vernon C. Applegate, Leonard N. Allison
1967, Papers of the Michigan Academy of Science, Arts, and Letters (52) 105-114
In recent years appreciable changes have taken place in the biota and physiochemical conditions in Lake Erie. The accelerated eutrophication of the lake has been accompanied by the near disappearance of several fish species, e.g., blue pike (Stizostedion vitreum glaucum), lake herring (Coregonus artedi), lake trout (Salvelinus namaycush), sauger...
Fishery picture changing in Lake Erie: pollution a major factor, survey shows
Harry D. Van Meter, William F. Shepherd
1967, Conservationist (22) 2-3
The objectives of these cruises of the research vessel Musky II in 1965 and 1966 were: To determine changes in the fish population and environmental conditions in recent years; to determine if the geographic and depth distributions of certain species of fish in the summer differed from that in the...
A low pressure investigation of the stability of phlogopite
D. R. Wones
1967, Geochimica et Cosmochimica Acta (31) 2248-2253
Phlogopite reacts to form orthorhombic kalsilite, leucite, forsterite and fluid (H2O) at 1012 ± 7°C, 400 bars pressure, and 905 ± 5°C at 100 bars pressure. The heat of reaction is 39 ± 4 kcal compared to 44 ± 6kcal for the reaction of annite to form orthorhombic kalsilite, leueite, fayalite...
Sediments and fossiliferous rocks from the eastern side of the Tongue of the Ocean, Bahamas
Thomas G. Gibson, John Schlee
1967, Deep-Sea Research and Oceanographic Abstracts (14) 691-694
In August 1966, two dives were made with the deep-diving submersible Alvin along the eastern side of the Tongue of the Ocean to sample the rock and sediment. Physiographically, the area is marked by steep slopes of silty carbonate sediment and precipitous rock cliffs dusted by carbonate debris. Three rocks, obtained from...
Molecular characteristics versus biological activity
Vernon C. Applegate, Manning A. Smith, Bennett R. Willeford
1967, Chemistry (40) 28-30
The molecular characteristics of mononitrophenols containing halogens not only play a key role in their biological activity but provide a novel example of selective toxicity among vertebrate animals. It has been reported that efforts to control the parasitic sea lamprey in the Great Lakes are directed at present to...
Observations on unmeasured rivers
Luna Bergere Leopold, Herbert E. Skibitzke
1967, Geografiska Annaler, Series A: Physical Geography (49) 247-255
An analysis of data on hydraulic parameters collected during a single boat trip down a river system is presented, plotted in form of the hydraulic geometry. A dimensionless rating curve is used to estimate bankfull and average discharge for basins of various sizes. When compared with gaging station data, estimates...
A seventeenth century mandibular tumor in a North American Indian
E.E. Kelln, E.V. McMichael, B. Zimmermann
1967, Oral Surgery, Oral Medicine, Oral Pathology (23) 78-81
The oldest tumor so far recorded is believed to have been a hemangioma. It occurred in a bone of a dinosaur’s tail1 and thus considerably antedates the historical period. The oldest known human tumor is much younger, dating back only to the middle of the third century after Christ.1 It...
Field Methods for the Study of Slope and Fluvial Processes
Luna Bergere Leopold, editor(s)
1967, Revue de Géomorphologie Dynamique (17) 147-187
In Belgium during the summer of 1966 the Commission on Slopes and the Commission on Applied Geomorphology of the International Geographical Union sponsored a joint symposium, with field excursions, and meetings of the two commissions. As a result of the conference and associated discussions, the participants expressed the view that...