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Publications

Filter Total Items: 822

Contrasting P‐T‐t paths: Thermochronologic evidence for a Late Paleozoic final assembly of the Avalon Composite Terrane in the New England Appalachians

Strongly contrasting pressure‐temperature‐time paths for the Avalon composite terrane and the structurally overlying Putnam‐Nashoba zone in eastern New England obtained from thermochronologic and thermobarometric data are best explained by a late Paleozoic underthrusting of cover rocks by the Avalon composite terrane. We present new Ar and U‐Pb thermochronologic data that show that in the southern
Authors
R. P. Wintsch, J. F. Sutter, Michael J. Kunk, John N. Aleinikoff, Michael J. Dorais

Closure of the Isthmus of Panama: The near-shore marine record of Costa Rica and western Panama

The final closure of the Isthmus of Panama at ∼3.5 Ma divided the American tropical ocean into two separate and different oceanographic regions. Consequences for the marine biota were profound, but, hitherto, correlation of the Pacific and Caribbean coastal sections has not been precise enough to track biologic patterns. We present here a correlation of 31 sections from the Pacific and Caribbean c
Authors
Anthony G. Coates, Jeremy B. C. Jackson, Laurel S. Collins, Thomas M. Cronin, Harry J. Dowsett, Laurel M. Bybell, Peter Jung, Jorge Obando

Alleghanian development of the Goat Rock fault zone, southernmost Appalachians: Temporal compatibility with the master decollement

The Goat Rock and associated Bartletts Ferry fault zones, which mark the eastern margin of the Pine Mountain Grenville basement massif, are controversial due to the suggestion that they are rare exposed segments of the late Paleozoic southern Appalachian master decollement. The controversy in part stems from reported middle Paleozoic (Acadian) radiometric dates postulated as the time of movement a
Authors
Mark G. Steltenpohl, S. Goldberg, T.B. Hanley, Michael J. Kunk

Calibration of the latest Eocene-Oligocene geomagnetic polarity time scale using 40 Ar/ 39 Ar dated ignimbrites

A discontinuous record of late Eocene-Oligocene geomagnetic polarity has been determined using high-precision (±<0.15 m.y.) 40Ar/39Ar sanidine dating and a paleomagnetic study of 37-27 Ma ignimbrites in New Mexico, Colorado, and Texas. This record provides age control for several geomagnetic polarity reversals that occurred during three periods of intense ignimbrite volcanism: 36.8-33.5 Ma, 32.7-3
Authors
W. C. McIntosh, J. W. Geissman, C.E. Chapin, Michael J. Kunk, Christopher D. Henry

Hydrogeology of thick till deposits in Connecticut

No abstract available.
Authors
Robert L. Melvin, Byron D. Stone, J. R. Stone, N.J. Trask

Paleocene and Eocene strata of the central Atlantic Coastal Plain

No abstract available.
Authors
Thomas G. Gibson, Laurel M. Bybell, David L. Govoni

Potomac River Paleocene and Eocene stop descriptions

No abstract available. 
Authors
Thomas G. Gibson, Laurel M. Bybell

The second Lehigh Tunnel; geology and the New Austrian Tunnelling Method

No abstract available.
Authors
Jack B. Epstein, Patricia F. Buis