Petrology and metamorphic history of metapelites in the Boehls Butte quadrangle, northern Idaho
Conference
·
· Geol. Soc. Am., Abstr. Programs; (United States)
OSTI ID:6644378
Metapelitic rocks in the Goat Mountain area record a pre-Beltian anatectic event and two later metamorphic events correlated to the M2 and M3 events observed by Lang and Rice. The co-occurrence of all three aluminosilicates is the result of M2 kyanite-sillimanite growth and M3 andalusite growth. The conditions of M2 metamorphism are estimated at 675 +/- 50/sup 0/C and 9.3 +/- 1.5 kb as determined from a variety of geothermo/barometers. M2 AFM mineral assemblages include Grt-Bt-Ky+/-Sil+/-Str and Crd-Bt-Ky+/-Sil. Partitioning of Mg and Fe in garnet and staurolite is normal (K/sub D/ > 1) for relict staurolite enclosed by aluminosilicate or muscovite and reversed (K/sub D/ < 1) for apparently stable staurolite and staurolite occurring as inclusions in garnet. Cordierite occurs as an overgrowth of kyanite; a texture which cannot be explained by reactions among the coexisting minerals. The texture may be explained by prograde consumption of chlorite or consumption of garnet upon decompression. The M3 event had limited effect on M2 mineral assemblages but resulted in crenulation and brittle deformation of M2 fabrics. The M3 event occurred during uplift and cooling following the M2 event. The M3 event is correlated to uplift of the Idaho batholith implying a Cretaceous age of M2 metamorphism.
- Research Organization:
- Univ. of Oregon, Eugene (USA)
- OSTI ID:
- 6644378
- Report Number(s):
- CONF-8510489-
- Conference Information:
- Journal Name: Geol. Soc. Am., Abstr. Programs; (United States) Journal Volume: 17
- Country of Publication:
- United States
- Language:
- English
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Conference
·
Sun Feb 28 23:00:00 EST 1993
· Geological Society of America, Abstracts with Programs; (United States)
·
OSTI ID:5934672
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Conference
·
Mon Dec 31 23:00:00 EST 1984
· Geol. Soc. Am., Abstr. Programs; (United States)
·
OSTI ID:6596617
Decompressional metamorphic P-T paths from kyanite-sillimanite-andalusite bearing rocks in north-central New Mexico
Conference
·
Tue Dec 31 23:00:00 EST 1991
· Geological Society of America, Abstracts with Programs; (United States)
·
OSTI ID:5807814
Related Subjects
15 GEOTHERMAL ENERGY
152004 -- Geothermal Data & Theory-- Isotope & Trace Element Studies
58 GEOSCIENCES
580300* -- Mineralogy
Petrology
& Rock Mechanics-- (-1989)
ALUMINIUM COMPOUNDS
ALUMINIUM SILICATES
CHLORITE MINERALS
CRETACEOUS PERIOD
FEDERAL REGION X
GARNETS
GEOBAROMETRY
GEOLOGIC AGES
GEOLOGIC HISTORY
GEOLOGY
GEOTHERMOMETERS
GEOTHERMOMETRY
IDAHO
MEASURING INSTRUMENTS
MESOZOIC ERA
METAMORPHIC ROCKS
METAMORPHISM
MICA
MINERALIZATION
MINERALOGY
MINERALS
MUSCOVITE
NORTH AMERICA
OXYGEN COMPOUNDS
PARTITION
PETROGENESIS
PETROLOGY
ROCKS
SILICATE MINERALS
SILICATES
SILICON COMPOUNDS
THERMOMETERS
USA
152004 -- Geothermal Data & Theory-- Isotope & Trace Element Studies
58 GEOSCIENCES
580300* -- Mineralogy
Petrology
& Rock Mechanics-- (-1989)
ALUMINIUM COMPOUNDS
ALUMINIUM SILICATES
CHLORITE MINERALS
CRETACEOUS PERIOD
FEDERAL REGION X
GARNETS
GEOBAROMETRY
GEOLOGIC AGES
GEOLOGIC HISTORY
GEOLOGY
GEOTHERMOMETERS
GEOTHERMOMETRY
IDAHO
MEASURING INSTRUMENTS
MESOZOIC ERA
METAMORPHIC ROCKS
METAMORPHISM
MICA
MINERALIZATION
MINERALOGY
MINERALS
MUSCOVITE
NORTH AMERICA
OXYGEN COMPOUNDS
PARTITION
PETROGENESIS
PETROLOGY
ROCKS
SILICATE MINERALS
SILICATES
SILICON COMPOUNDS
THERMOMETERS
USA