Now showing items 31-40 of 173
Ultra-high temperatures from oxygen isotope thermometry of a coesite-sanidine grospydite
(Springer-Verlag, 1992-11)
The oxygen isotope compositions of coesite, sanidine, kyanite, clinopyroxene and garnet were measured in an ultra-high pressure-temperature grospydite from the Roberts Victor kimberlite, South Africa. The δ 18 O values ...
Organic geochemical study of mineralization in the Keweenawan Nonesuch Formation at White Pine, Michigan
(Elsevier, 1990)
The role of organic matter in the formation of metal ores has been investigated in the Nonesuch Formation at White Pine, Michigan. Organic matter in mineralized strata was characterized by isotopic, molecular and ...
Silicon in magnetite: High resolution microanalysis of magnetite-ilmenite intergrowths
(Springer-Verlag, 1982-11)
Magnetite-ilmenite “oxidation-exsolution” intergrowths from an original titanomagnetite microphenocryst from an ash flow tuff unit have been studied using conventional transmission electron microscopy and analytical electron ...
Regional retrograde alteration of sub-greenschist facies chlorite to smectite
(Springer-Verlag, 1994-01)
Dioctahedral smectite is present as a retrograde alteration product of chlorite in Permian-Triassic red slates of the Malaguide Complex in Sierra de Espuña (Betic Cordillera). Mineral assemblages and textures, illite ...
Formation waters from Mississippian-Pennsylvanian reservoirs, Illinois basin, USA: Chemical and isotopic constraints on evolution and migration
(Elsevier, 1993-02)
We have analyzed a suite of seventy-four formation-water samples from Mississippian and Pennsylvanian carbonate and siliciclastic strata in the Illinois basin for major, minor, and trace element concentrations and for ...
Europium anomalies and the genesis of basalt: A discussion
(Elsevier, 1969-06)
The argument advanced by Philpotts and Schnetzler that europium anomalies in igneous rocks and minerals are mainly caused by crystal chemistry without control by oxidation-reduction reactions is refuted on the grounds that ...
Fatty acids and hydrocarbons in surficial sediments of Lake Huron
(Elsevier, 1979-07)
Fatty acid and hydrocarbon distributions in surficial sediments from ten locations in southern Lake Huron indicate both aquatic and terrigenous recent biological sources of these geolipid materials. Normal alkanoic acids ...
Mineralogical and biological controls on the Fe/Ca and Mn/Ca ratios of lacustrine carbonate allochems
(Elsevier, 1983-01)
The Fe/Ca and Mn/Ca ratios of lacustrine carbonate allochems are primarily controlled by the mineralogy of the carbonate polymorph. However, these ratios are subject to a significant degree of biological control among ...
Stable isotope geochemistry and phase equilibria of coesite-bearing whiteschists, Dora Maira Massif, western Alps
(Springer-Verlag, 1993-05)
Peak metamorphic temperatures for the coesite-pyrope-bearing whiteschists from the Dora Maira Massif, western Alps were determined with oxygen isotope thermometry. The δ 18 O( smow ) values of the quartz (after coesite) ...