Chronostratigraphy of the Trenton Group and Utica Shale, Pt. II: Stratigraphic correlations using Ordovician glasses in K-bentonites

Conference · Wed Jan 01 00:00:00 EST 1992 · Geological Society of America, Abstracts with Programs; (United States)

OSTI ID:5589155

Delano, J W; Tice, S ^[1]; Mitchell, C E; Goldman, D ^[2]; Samson, S D ^[3]

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1. State Univ. of New York, Albany, NY (United States). Dept. of Geological Sciences
2. State Univ. of New York, Buffalo, NY (United States). Dept. of Geology
3. Syracuse Univ., NY (United States). Dept. of Geology

Rhyolitic glasses in the form of pristine melt inclusions that occur within quartz phenocrysts are being used for the geochemical fingerprinting of Ordovician K-bentonites in the northern Appalachian Basin. These melt inclusions are samples of pre-eruptive magma that became trapped during phenocryst growth in the deep crustal magma chambers. Plinian eruptions led to quenching of the enclosed rhyolitic magma to form glass when the quartz phenocrysts were blasted into the atmosphere. Preservation of this Ordovician glass is due to its being hermetically sealed within a mineral (quartz) that is resistant to weathering and diagenetic alteration. Chemical compositions of glasses in four Ordovician K-bentonites from the Mohawk Valley of New York State have been acquired using high-precision, electron microprobe analyses. The elements Mg, Cl, Ca, Ti, and Fe are often diagnostic. The accompanying figure illustrates one combination of elements that is effective in distinguishing K-bentonites, which are not stratigraphically equivalent. These K-bentonites were selected to test competing chronostratigraphies of the northern Appalachian Basin and indicate problems with the model by Cisne et al.

• OSTI ID: 5589155
• Report Number(s): CONF-921058-; CODEN: GAAPBC
• Journal Information: Geological Society of America, Abstracts with Programs; (United States), Vol. 24:7; Conference: 1992 annual meeting of the Geological Society of America (GSA), Cincinnati, OH (United States), 26-29 Oct 1992; ISSN 0016-7592
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
NEW YORK
SEDIMENTARY BASINS
GEOCHEMISTRY
AGE ESTIMATION
BENTONITE
CHEMICAL COMPOSITION
GLASS
INCLUSIONS
ORDOVICIAN PERIOD
STRATIGRAPHY
CHEMISTRY
CLAYS
DEVELOPED COUNTRIES
GEOLOGIC AGES
GEOLOGIC STRUCTURES
GEOLOGY
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
MATERIALS
NORTH AMERICA
PALEOZOIC ERA
USA
580000* - Geosciences