Now showing items 171-180 of 192
Electrochemical measurements bearing on the oxidation state of the Skaergaard Layered Intrusion
(Springer-Verlag, 1989-07)
The oxygen fugacities (fO 2 's) of magnetically-concentrated fractions (MCF) of three rock samples from the Skaergaard Layered Intrusion were measured between 800–1150° C using oxygen-specific, solid zirconia electrolytes ...
Occurrence of wide-chain Ca-pyriboles as primary crystals in the Salton Sea Geothermal Field, California, USA
(Springer-Verlag, 1986-09)
Amphiboles and pyroxenes occurring in the Salton Sea Geothermal Field were found to contain coherent intergrowths of chain silicates with other than double and single chain widths by using transmission and analytical ...
Geochemistry of eolian dust in Pacific pelagic sediments: Implications for paleoclimatic interpretations
(Elsevier, 1991-08)
Geochemical data (REEs, Th, Sc) were determined for the operationally defined eolian dust (ODED) fraction (n = 57) from the north and equatorial Pacific Ocean. Paleoclimate studies commonly have assumed that this sediment ...
Phyllosilicates in hydrothermally altered basalts from DSDP Hole 504B, Leg 83 — a TEM and AEM study
(Springer-Verlag, 1992-10)
Phyllosilicates occurring as replacements of olivine, clinopyroxene and interstitial materials and as veins or fracture-fillings in hydrothermally altered basalts from DSDP Hole 504B, Leg 83 have been studied using ...
An analytical electron microscopic study of a pyroxene-amphibole intergrowth
(Springer-Verlag; Springer-Verlag GmbH & Co. KG, 1981-06)
Samples of a garnet granulite from the mafic border units of the Lake Chatuge, Georgia alpine peridotite body were found to contain lamellar intergrowths of a pargastic amphibole in augite having the typical appearance of ...
40Ar/39Ar dating of very fine-grained samples: An encapsulated-vial procedure to overcome the problem of 39Ar recoil loss
(Elsevier, 1992-12-15)
40Ar/39Ar dating of very fine-grained materials is compromised by the loss of 39Ar by recoil, and also sometimes other Ar isotopes, during irradiation. An encapsulated sample 40Ar/39Ar procedure is described which overcomes ...
The Aurora volcanic field, California-Nevada: oxygen fugacity constraints on the development of andesitic magma
(Springer-Verlag; Springer-Verlag Berlin Heidelberg, 1996-10)
The Aurora volcanic field, located along the northeastern margin of Mono Lake in the Western Great Basin, has erupted a diverse suite of high-K and shoshonitic lava types, with 48 to 76 wt% SiO 2 , over the last 3.6 million ...
Sr/Ca and Mg/Ca ratios in polygenetic carbonate allochems from a Michigan marl lake
(Elsevier, 1981-03)
Rapid accumulation of CaCO3 is occurring in Littlefield Lake, a marl lake located in central Michigan. The sediment, which is 95% CaCO3, primarily consists of eight different genetic groups of carbonate allochems. These ...