Modes of occurrence and geochemistry at DSDP Holes 69-505A and 69-505B
| Cobertura |
MEDIAN LATITUDE: 1.918400 * MEDIAN LONGITUDE: -83.789150 * SOUTH-BOUND LATITUDE: 1.916800 * WEST-BOUND LONGITUDE: -83.790000 * NORTH-BOUND LATITUDE: 1.920000 * EAST-BOUND LONGITUDE: -83.788300 * DATE/TIME START: 1979-09-29T00:00:00 * DATE/TIME END: 1979-09-29T00:00:00 |
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| Data(s) |
19/07/1983
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| Resumo |
The compositions of chrome spinels of Costa Rica Rift basalts from Deep Sea Drilling Project Site 505 vary depending on their occurrences as (1) inclusions in olivine crystals, (2) inclusions in Plagioclase crystals, and (3) isolated crystals in variolitic or glassy samples. The variations are a consequence of (1) changes of melt compositions as crystallization proceeds, and (2) contrasting behavior of olivine and Plagioclase in competition with spinels for Al and Mg. Some spinels have skeletal rims compositionally less magnesian than mineral cores; however, the cores do not appear to be xenocrysts, unlike some texturally similar spinels in Mid-Atlantic Ridge basalts. |
| Formato |
application/zip, 2 datasets |
| Identificador |
https://doi.pangaea.de/10.1594/PANGAEA.817000 doi:10.1594/PANGAEA.817000 |
| Idioma(s) |
en |
| Publicador |
PANGAEA |
| Direitos |
CC-BY: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted |
| Fonte |
Supplement to: Furuta, Toshio; Tokuyama, Hidekazu (1983): Chromian spinels in Costa Rica Rift basalts, Deep Sea Drilling Project Site 505 - A preliminary interpretation of electron microprobe analyses. In: Cann, JR; Langseth, MG; Honnorez, J; Von Herzen, RP; White, SM; et al. (eds.), Initial Reports of the Deep Sea Drilling Project (U.S. Govt. Printing Office), 69, 805-810, doi:10.2973/dsdp.proc.69.153.1983 |
| Palavras-Chave | #69-505A; 69-505B; Al; Al2O3; Aluminium; Aluminium oxide; Calculated based on oxygen number; Calculated from total Fe and structural formula; Chromium; Chromium(III) oxide; Chromium number; Coexisting olivine, maximum; Coexisting olivine, minimum; ?0 = values unknown; Cr; Cr/(Cr + Al); Cr2O3; Deep Sea Drilling Project; Description; Diameter; DRILL; Drilling/drill rig; DSDP; Electron microprobe; Event; Fe2+; Fe3+; FeO; Fo; Forsterite; Glomar Challenger; Grains; Iron 2+; Iron 3+; Iron oxide, FeO; Isolated; Label; Leg69; Magnesium; Magnesium number; Magnesium oxide; Manganese; Manganese oxide; Mg; Mg/(Mg + Fe); Mg/(Mg + Fe2+); MgO; Mn; MnO; Ni; Nickel; Nickel oxide; NiO; North Pacific/GRABEN; ODP sample designation; Ol; Olivine; Pl; Plagioclase; Sample code/label; Sample ID; Si; Silicon; Silicon dioxide; SiO2; Ti; TiO2; Titanium; Titanium oxide; Total; Total iron; V; V2O5; Vanadium; Vanadium oxide; Ø |
| Tipo |
Dataset |
