Now showing items 1-10 of 61
An unmetasomatized source for the Malaitan alnoite (Solomon Islands): Petrogenesis involving zone refining, megacryst fractionation, and assimilation of oceanic lithosphere
(Elsevier, 1989-08)
The Malaitan alnoite contains a rich and varied megacryst suite of unprecedented compositional range. We have undertaken trace element and isotope modeling in order to formulate a petrogenetic scheme which links the host ...
The hydrothermal component in ferromanganese nodules from the southeast Pacific Ocean
(Elsevier, 1989-06)
Statistical analyses of geochemical data from ferromanganese nodule samples representing a broad area of the southeast Pacific Ocean indicate nodule compositions are controlled by four factors: (1) suboxic diagenesis; (2) ...
Oxidation states of the upper mantle recorded by megacryst ilmenite in kimberlite and type A and B spinel lherzolites
(Springer-Verlag, 1984-01)
The intrinsic oxygen fugacities of homogeneous, inclusion-free, megacryst ilmenites from the Frank Smith, Excelsior, Sekameng and Mukorob kimberlite pipes in southern Africa, and the alnöitic breccia in the Solomon Islands ...
Sedimentary biomarker and isotopic indicators of the paleoclimatic history of the Walker Lake basin, western Nevada
(Elsevier, 1988)
Walker Lake, a terminal saline lake in western Nevada, has experienced major fluctuations in its water level due to changes in the regional climate during Quaternary times. As part of a paleo-climatological study of western ...
Comparison of lipid character of sediments from the Great Lakes and the Northwestern Atlantic
(Elsevier, 1984)
Geolipid compositions of surficial sediments from Lake Michigan, Lake Huron, and from three locations in the Northwestern Atlantic were determined to compare source inputs and alteration processes in different sedimentary ...
Contrasting serpentinization processes in the eastern Central Alps
(Springer-Verlag, 1988-08)
Stable isotope compositions have been determined for serpentinites from between Davos (Arosa-Platta nappe, Switzerland) and the Valmalenco (Italy). δD and δ 18 O values (−120 to −60 and 6–10‰, respectively) in the Arosa-Platta ...
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 ...
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 ...
Petrology of spinel harzburgite xenoliths from the Kishb Plateau, Saudi Arabia
(Springer-Verlag, 1986-07)
Two spinel harzburgite xenoliths from a Pleistocene alkali basalt unit erupted at the northwestern corner of the Tertiary Kishb Plateau (Saudi Arabia) are characterized by an incipient transition from protogranular to ...