Publications
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Correlation of late Cenozoic basaltic lava flows in the Carbondale and Eagle collapse centers in west-central Colorado based on geochemical, isotopic, age, and petrographic data
Major-, minor-, and trace-element abundance data on 220, late Cenozoic, basaltic rocks in and around the Carbondale and Eagle collapse centers in west-central Colorado are combined with isotopic, age, and petrographic data to correlate lava flows and establish the timing and minimum areal extent of collapse events associated with removal of Pennsylvanian evaporite. On the basis of these data, 46 d
Authors
James R. Budahn, D. M. Unruh, Michael J. Kunk, Frank M. Byers, R. M. Kirkham, R. K. Streufert
Tertiary cooling and tectonic history of the White River uplift, Gore Range, and western Front Range, central Colorado: Evidence from fission-track and 39Ar/ 40Ar ages
Apatite fission-track (AFT) data from Proterozoic and Paleozoic rocks in the mountains of north central Colorado (White River Uplift, Gore Range, and western Front Range) record significant cooling that began with uplift and erosion related to the Laramide Orogeny and continued through the Tertiary to Pliocene time. The mountains immediately flanking the Blue River half graben (Williams Fork Mount
Authors
C.W. Naeser, Bruce Bryant, Michael J. Kunk, Karl S. Kellogg, R.A. Donelick, W. J. Perry
40Ar/39Ar ages of late Cenozoic volcanic rocks within and around the Carbondale and Eagle collapse centers, Colorado: Constraints on the timing of evaporite-related collapse and incision of the Colorado River
40Ar/ 39Ar dating results of 133 samples from 84 late Cenozoic volcanic rocks provide emplacement ages that constrain the timing of evaporite collapse and the incision rates of the Colorado River. Our samples are from areas in west-central Colorado, both within and outside of the Carbondale and Eagle collapse centers. Significant pulses of volcanic activity occurred in the intervals from 24 to 22,
Authors
Michael J. Kunk, James R. Budahn, D. M. Unruh, Josette O. Stanley, R. M. Kirkham, Bruce Bryant, R. B. Scott, David J. Lidke, R. K. Streufert
Eagle collapse center: Interpretation of evidence for late Cenozoic evaporite-related deformation in the Eagle River basin, Colorado
Evaporite tectonism resulted in deformation and collapse over an area of ~2500 km2 that is referred to as the Eagle collapse center. The collapse center includes much of the Eagle and Colorado River drainage basins between Vail, Dotsero, and McCoy, Colorado. The volume loss of evaporitic rocks by dissolution in the collapse center is estimated to be nearly 1700 km33 . Before ca. 10 Ma, Miocene bas
Authors
David J. Lidke, Mark R. Hudson, R. B. Scott, Ralph R. Shroba, Michael J. Kunk, W. J. Perry, R. M. Kirkham, James R. Budahn, R. K. Streufert, J.O. Stanley, B.L. Widmann
Structural and tectonic setting of the Charleston, South Carolina, region: Evidence from the Tertiary stratigraphic record
Eleven upper Eocene through Pliocene stratigraphic units occur in the subsurface of the region surrounding Charleston, South Carolina. These units contain a wealth of information concerning the long-term tectonic and structural setting of that area. These stratigraphic units have a mosaic pattern of distribution, rather than a simple layered pattern, because deposition, erosion, and tectonic warpi
Authors
R. E. Weems, W.C. Lewis
Stream piracy in the Black Hills: A geomorphology lab exercise
The Black Hills of South Dakota exhibits many fine examples of stream piracy that are very suitable for teaching geomorphology lab exercises. This lab goes beyond standard topographic map interpretation by using geologic maps, well logs, gravel provenance and other types of data to teach students about stream piracy. Using a step-by-step method in which the lab exercises ramp up in difficulty, stu
Authors
Brent J. Zaprowski, Edward B. Evenson, Jack B. Epstein
Road log and stop descriptions; Day 1, Stop 1; Delaware Water Gap; geologic overview, stratigraphy, structure, formation of the gap, and glacial geology
No abstract available.
Authors
Jack B. Epstein
Structural relations along the Taconic unconformity between New York, New Jersey, and Pennsylvania
No abstract available.
Authors
Jack B. Epstein, Peter T. Lyttle
Structural geology of the Delaware Water Gap National Recreation Area
No abstract available.
Authors
Jack B. Epstein
Stratigraphy in the region of Delaware Water Gap National Recreation Area
No abstract available.
Authors
Jack B. Epstein
Road log and stop descriptions; Day 2, Stop 7; East Stroudsburg railroad cut; Schoharie Formation and Onondaga Limestone; stratigraphy and structure
No abstract available.
Authors
C. A. Ver Straeten, J. D. Inners, Jack B. Epstein
Road log and stop descriptions; Day 1, Stop 6; High Point; overview of bedrock geology, geomorphology, and the Culvers Gap River
No abstract available.
Authors
Jack B. Epstein, Donald H. Monteverde, Ron W. Witte