Publications
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Composition of biotite phenocrysts in Ordovician tephras casts doubt on the proposed trans-Atlantic correlation of the Millbrig K-bentonite (United States) and the Kinnekulle K-bentonite (Sweden) Composition of biotite phenocrysts in Ordovician tephras casts doubt on the proposed trans-Atlantic correlation of the Millbrig K-bentonite (United States) and the Kinnekulle K-bentonite (Sweden)
Biotite phenocryst compositions in three thick, widespread Ordovician K-bentonites, the Deicke and Millbrig from Big Ridge, Alabama, and the Kinnekulle from Mossen, Västergötland, Sweden, fall into three distinct groups, and so the proposed intercontinental correlation of the Millbrig and the Kinnekulle is suspect. Because the biotites are nearly pristine compositionally, electron...
Authors
John Haynes, W.G. Melson, Michael Kunk
An 40Ar/39Ar thermochronology of the Ofoten‐Troms region: Implications for terrane amalgamation and extensional collapse of the northern Scandinavian Caledonides An 40Ar/39Ar thermochronology of the Ofoten‐Troms region: Implications for terrane amalgamation and extensional collapse of the northern Scandinavian Caledonides
Fifteen 40Ar/39Ar cooling ages are reported for metamorphic hornblende and muscovite from far traveled terranes constituting the Ofoten nappe stack of northern Norway. Eight cooling ages on hornblende range from 425 to 394 Ma and seven muscovite ages, from the same or nearby outcrops as the hornblendes, range from 400 to 373 Ma. These data are compared with 40Ar/39Ar ages from over a...
Authors
Janet Coker, Mark Steltenpohl, A. Andersen, Michael Kunk
Age of the Cenomanian-Turonian boundary in the Western Interior of the United States Age of the Cenomanian-Turonian boundary in the Western Interior of the United States
High precision 40Ar/39Ar laser-microprobe ages of individual sanidines,40Ar/39Ar plateau age spectra on bulk sanidine concentrates, U-Pb zircon ages, and zircon and apatite fission-track ages from three bentonites bracketing the Cenomanian-Turonian boundary in the Western Interior of the United States suggest an age for the boundary of 93.1 ± 0.3 (2σ. The lowermost bentonite comes from...
Authors
B. Kowallis, Eric Christiansen, Alan Deino, Michael Kunk, L. Heaman
Geology of the Waterford quadrangle, Virginia and Maryland, and the Virginia part of the Point of Rocks quadrangle Geology of the Waterford quadrangle, Virginia and Maryland, and the Virginia part of the Point of Rocks quadrangle
The bedrock geology of the Waterford quadrangle and of the Virginia part of the Point of Rocks quadrangle consists of a portion of the Middle Proterozoic basement core and its cover sequence on the eastern limb of the Blue Ridge anticlinorium and the adjacent early Mesozoic Culpeper basin. The three major rock associations in this area are: 1) Middle Proterozoic gneisses intruded by late
Authors
William Burton, A.J. Froelich, J. Pomeroy, K. Lee
Preliminary analysis of integrated stratigraphic data from the Phred #1 corehole, Indian River County, Florida Preliminary analysis of integrated stratigraphic data from the Phred #1 corehole, Indian River County, Florida
No abstract available.
Authors
S.D. Weedman, T.M. Scott, Lucy Edwards, G. L. Brewster-Wingard, J.C. Libarkin
Map showing bedrock surface topography, bedrock outcrops, and areas of shallow bedrock in the northern sheet, New Jersey Map showing bedrock surface topography, bedrock outcrops, and areas of shallow bedrock in the northern sheet, New Jersey
No abstract available.
Authors
Byron Stone, Scott Stanford, Ron Witte
Age and diagenesis of the upper Floridan Aquifer and the intermediate aquifer system in southwestern Florida Age and diagenesis of the upper Floridan Aquifer and the intermediate aquifer system in southwestern Florida
No abstract available.
Authors
Lucy McCartan, S.D. Weedman, G.L. Wingard, Lucy Edwards, P. Sugarman, M.D. Feigenson, M. L. Buursink, J.C. Libarkin
U-Pb ages of metarhyolites of the Catoctin and Mount Rogers formations, central and southern Appalachians: Evidence for two pulses of Iapetan rifting U-Pb ages of metarhyolites of the Catoctin and Mount Rogers formations, central and southern Appalachians: Evidence for two pulses of Iapetan rifting
No abstract available.
Authors
John Aleinikoff, Robert Zartman, Marianne Walter, Douglas W. Rankin, Peter Lyttle, William Burton
Impact of the 1993 floods in the upper Mississippi River basin Impact of the 1993 floods in the upper Mississippi River basin
No abstract available.
Authors
J. Dohrenwend, Byron Stone
Sedimentary patterns across the Paleocene-Eocene boundary in the Atlantic and Gulf Coastal Plains of the United States Sedimentary patterns across the Paleocene-Eocene boundary in the Atlantic and Gulf Coastal Plains of the United States
Fossiliferous clay and sand belonging to calcareous nannofossil Zones NP 9 (latest Paleocene) and NP 10 (earliest Eocene) are widespread in the US Gulf and Atlantic Coastal Plains. Although the thickness of Zone NP 9-NP 10 strata is several times greater in the eastern Gulf Coastal Plain than in the Atlantic Coastal Plain, the hiatus that usually is present between these two zones in...
Authors
Thomas Gibson, Laurel Bybell
The scientific assessment and strategy team contributions assessing the 1993 flood on the Mississippi and Missouri River basins The scientific assessment and strategy team contributions assessing the 1993 flood on the Mississippi and Missouri River basins
The Scientific Assessment and Strategy Team was formed to provide scientific advice and assistance to federal officials responsible for making decisions with respect to flood recovery in the Upper Mississippi River Basin (above Cairo, Illinois) as a result of the 1993 flooding. The team assembled data from a wide variety of sources within federal, state, and local governments, and the...
Authors
Gary Freeman, S. Nanda, M. Mausback, Ronald Erickson, John Kelmelis, Byron Stone, William Kirby, James Reel
Flow path studies in forested watersheds of headwater tributaries of Brush Brook, Vermont Flow path studies in forested watersheds of headwater tributaries of Brush Brook, Vermont
An investigation was undertaken into how headwater tributaries of Brush Brook, Vermont, could have average pH differences of almost two units (4.75 and 6.7). Sampling along four tributaries revealed that most of one tributary, below an area of seeps, had consistently higher pH, Ca2+, Mg2+, and K+, and lower Al than other sites. Bedrock mapping showed numerous fractures in vicinity of the...
Authors
Donald S. Ross, R. Bartlett, Frederick Magdoff, Gregory Walsh