Publications
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The Pennsylvanian Fire Clay tonstein of the Appalachian basin—Its distribution, biostratigraphy, and mineralogy
The Middle Pennsylvanian Fire Clay tonstein, mostly kaolinite and minor accessory minerals, is an altered and lithified volcanic ash preserved as a thin, isochronous layer associated with the Fire Clay coal bed. Seven samples of the tonstein, taken along a 300-km traverse of the central Appalachian basin, contain cogenetic phenocrysts and trapped silicate-melt inclusions of a rhyolitic magma. The
Authors
C. L. Rice, Harvey E. Belkin, T.W. Henry, R. E. Zartman, Michael J. Kunk
Digital bedrock geologic map of the Mount Holly and Ludlow quadrangles, Vermont: Database
No abstract available.
Authors
Gregory J. Walsh, Nicholas M. Ratcliffe, John B. Dudley, Thomas Merrifield
Digital bedrock geologic map of the Mount Holly and Ludlow quadrangles, Vermont
No abstract available.
Authors
Gregory J. Walsh, Nicholas M. Ratcliffe, John B. Dudley, Thomas Merrifield
Digital bedrock geologic map of the Plymouth quadrangle, Vermont
No abstract available.
Authors
Gregory J. Walsh, Nicholas M. Ratcliffe
Digital bedrock geologic map of the Plymouth quadrangle, Vermont
No abstract available.
Authors
Gregory J. Walsh, Nicholas M. Ratcliffe
Paleogene stratigraphy of the Solomons Island, Maryland, corehole
The Solomons Island corehole was drilled in the hope of obtaining a continuous and more nearly complete section of upper Paleocene and lower Eocene strata than are found in the discontinuous and fragmentary sections in the outcrop belt to the west. Consultation with Harry Hansen (Maryland Geological Survey) on possible drilling sites that were within the limits of our equipment and funding led to
Authors
Thomas G. Gibson, Laurel M. Bybell
Preliminary analysis of integrated stratigraphic data from the South Venice corehole, Sarasota County, Florida
No abstract available.
Authors
G. Lynn Brewster-Wingard, S.D. Weedman, T.M. Scott, Lucy E. Edwards, R.C. Green
Palynomorph biostratigraphy of Eocene samples from the Sagavanirktok Formation at Franklin Bluffs, North Slope of Alaska
No abstract available.
Authors
Norman O. Frederiksen, Lucy E. Edwards, T. D. Fouch, L. D. Carter, T. S. Collett
Geologic, hydrologic, and water-quality data for a multi-aquifer system in Coastal Plain sediments near Millers Pond, Burke County, Georgia, 1992-93
No abstract available.
Authors
John S. Clarke, William F. Falls, Lucy E. Edwards, Norman O. Frederiksen, Laurel M. Bybell, Thomas G. Gibson, Ronald J. Litwin
Calcareous nannofossils from Paleogene deposits in the Salt Range, Pakistan
No abstract available.
Authors
Laurel M. Bybell, Jean Self-Trail
The Manson Impact Structure: 40Ar/39Ar age and its distal impact ejecta in the Pierre Shale in southeastern South Dakota
The 40Ar/39Ar ages of a sanidine clast from a melt-matrix breccia of the Manson, Iowa, impact structure (MIS) indicate that the MIS formed 73.8 ± 0.3 million years ago (Ma) and is not coincident with the Cretaceous-Tertiary boundary (64.43 ± 0.05 Ma). The MIS sanidine is 9 million years older than 40Ar/39Ar age spectra of MIS shock-metamorphosed microcline and melt-matrix breccia interpreted earli
Authors
G. A. Izett, W. A. Cobban, J. Obradovich, Michael J. Kunk
40Ar/39Ar thermochronology and Alleghanian development of the southernmost Appalachian Piedmont, Alabama and southwest Georgia
40Ar/39Ar age spectra of hornblende, muscovite, and microcline, and total fusion ages of biotite from metamorphic rocks of the Inner Piedmont, Pine Mountain, and Uchee belts are reported. Mineral cooling ages from the eastern part of the Inner Piedmont are as follows: hornblende, 320 Ma; muscovite, 296 Ma; biotite, 293 Ma; and microcline (diffusional release patterns) Tmax = 267 Ma, Tmin = 234 Ma.
Authors
Mark G. Steltenpohl, Michael J. Kunk