HR: 0800h
AN: GP21B-0160 [Abstracts]
TI: Diagenetic Origin of Iron Oxides in Plagioclase
AU: * MacDonald, W D
EM: wdmacdon@binghamton.edu
AF: Dept Geological Sciences, SUNY Binghamton, Vestal Parkway East, Binghamton, NY 13850
United States
AU: Poulos, C
EM: christinapoulos@hotmail.com
AF: Dept Geological Sciences, SUNY Binghamton, Vestal Parkway East, Binghamton, NY 13850
United States
AB:
Oriented iron oxide inclusions in plagioclase are typically related to high-temperature phenomena, resulting from exsolution
and/or oxidation during crystallization and cooling of igneous rocks. Empirical observations suggest that low-temperature
alteration, associated with diagenesis, can account for some oriented iron oxides in plagioclase. These late oxides occur
adjacent to margins and fractures in plagioclase crystals and have implications to the interpretation of remanence. Examples
include plagioclase from ashflow tuffs (Bishop Tuff, California) and basalt (Parana basalt, Vargeao impact structure,
Brasil).
DE: 3620 Crystal chemistry
DE: 3640 Igneous petrology
DE: 1518 Magnetic fabrics and anisotropy
DE: 1519 Magnetic mineralogy and petrology
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2004 AGU Fall Meeting