Geology and petrogenesis of the Kirkpatrick Basalt, Pain Mesa and Solo Nunatak, northern Victoria Land, Antarctica
The flows on Pain Mesa were divided into a Lower Suite and an Upper Suite based on differences in their chemical compositions. The Upper Suite has higher concentrations of SiO/sub 2/, alkalies, total Fe, MnO, TiO/sub 2/, and P/sub 2/O/sub 5/ than the Lower Suite. In addition, the flows of the Upper Suite are homogeneous in chemical composition compared to the Lower Suite which is differentiated. The isotope compositions of Sr and O of the Lower Suite are positively correlated which indicates that the magma was contaminated by crustal material. The isotopic and chemical compositions of the flows of the Lower Suite were explained by fractional crystallization and simultaneous assimilation of a crustal contaminant. The initial Sr isotope ratios of the Upper Suite, calculated for an assumed age of 175 Ma, were lower than those of the Lower Suite, and are not constant. However, by lowering the assumed age of the Upper Suite to 92 Ma the range of the initial Sr-isotope ratios was greatly reduced. Paleomagnetic results and K-Ar dating of Ferrar rocks at the Litell Rocks Nunatak in northern Victoria Land also support the hypothesis that the Upper Suite is Cretaceous in age. The magma source of both suites has elevated /sup 87/Sr//sup 86/Sr ratios compared to normal mantle values because of prior enrichment in Rb. The magma source was enriched in Rb about 475 Ma years ago. This data coincides with the Ross Orogeny which may reflect a causal relationship between these events. The occurrence of igneous activity in northern Victoria Land and Marie Byrd Land were juxtaposed during the Mesozoic Era but were later separated as a result of major right lateral displacement along the Transantarctic rift system.
- Research Organization:
- Ohio State Univ., Columbus (USA)
- OSTI ID:
- 7188901
- Resource Relation:
- Other Information: Thesis (Ph. D.)
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ANTARCTICA
GEOLOGIC DEPOSITS
GEOCHEMISTRY
GEOLOGIC HISTORY
AGE ESTIMATION
ARGON
CONTINENTAL CRUST
CORRELATIONS
ENRICHMENT
GEOLOGY
IRON
ISOTOPE DATING
ISOTOPE RATIO
MAGMA
MANGANESE OXIDES
OXYGEN
PALEOMAGNETISM
PHOSPHORUS OXIDES
POTASSIUM
RUBIDIUM
SILICON OXIDES
STRONTIUM
STRONTIUM 86
STRONTIUM 87
TECTONICS
TITANIUM OXIDES
ALKALI METALS
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METALS
ANTARCTIC REGIONS
BETA DECAY RADIOISOTOPES
CHALCOGENIDES
CHEMISTRY
EARTH CRUST
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
FLUIDS
GASES
HOURS LIVING RADIOISOTOPES
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MAGNETISM
MANGANESE COMPOUNDS
METALS
NONMETALS
NUCLEI
OXIDES
OXYGEN COMPOUNDS
PHOSPHORUS COMPOUNDS
POLAR REGIONS
RADIOISOTOPES
RARE GASES
SILICON COMPOUNDS
STABLE ISOTOPES
STRONTIUM ISOTOPES
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
580100* - Geology & Hydrology- (-1989)
580400 - Geochemistry- (-1989)