Preservation of oxygen isotope compositions in granulites from Northwestern Canada and Enderby Land, Antarctica: implications for high-temperature isotopic thermometry

Article Abstract:

Oxygen isotopic thermometry and data-handling techniques facilitate the estimation of mineral-pair closure temperature for the high temperature, dry granulites of Northwestern Canada and Enderby Land, Antarctica. Isotopic compositions of garnet indicate temperatures greater than 950 degrees celsius. The quartz-magnetite pair exchanged oxygen during ductile deformation, while garnet was unaffected. Garnet's suitability for isotopic thermometry is discussed. The significance of the dry nature of granulites for the preservation of high-temperature isotopic compositions is addressed.

Granulite

---

Isotopic and chemical constraints on the crustal evolution and source signature of Ferrar magmas, north Victoria Land, Antarctica

Article Abstract:

The geochemical and isotopic data of the Ferrar rocks from north Victoria Land, Antarctica, suggest a resemblance to granitoids formed in the early Paleozoic Ross Orogeny. The isotopic structure of the rocks develops from Ross-type material. Many factors may be involved in the production of a variety of compositions exhibited by the rocks. For one example, analysis of the mineral composition and steady epsilon(sub Nd) values indicates differences in alkali content which produces alterations in the ratio of Sr(super 87) to Sr(super 86).

Methods, Natural history, Antarctic regions, Leaching, Magma

---

The oxygen isotope fractionation behaviour of kyanite in experiment and nature

Article Abstract:

A study was conducted to analyze the oxygen isotope fractionation between kyanite and calcium carbonate at four temperatures. The isotopic reaction was improved by the polymorphic transformation of andalusite to kyanite. Results indicated that refractory behavior hindered the application of kyanite for thermometry and supports the use of its O-isotope composition as a basis for recognizing polymetamorphic rock histories.

Oxygen, Oxygen isotopes, Calcium carbonate

Similar abstracts:

• Abstracts: Chemical and isotopic variations in an iron-rich lava flow from the Kirkpatrick Basalt, north Victoria Land, Antarctica: implications for low-temperature alteration
• Abstracts: Carbon fixation by phytoplankton in high Arctic lakes: implications of low temperature for photosynthesis. Laboratory measurements of angular distributions of light scattered by phytoplankton and silt
• Abstracts: Multiphase inclusions in plagioclase from anorthosites in the Stillwater Complex, Montana: implications for the origin of the anorthosites
• Abstracts: Remagnetization of Cretaceous forearc strata on Santa Margarita and Magdalena Islands, Baja California Sur: implications for northward transport along the California margin
• Abstracts: Gravity fields in eastern Halmahera and the Bonin Arc: implications for ophiolite origin and emplacement. Cenozoic motion of the Philippine Sea Plate: palaeomagnetic evidence from eastern Indonesia

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.