Publications
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Short-term survival of ammonites in New Jersey after the end-Cretaceous bolide impact Short-term survival of ammonites in New Jersey after the end-Cretaceous bolide impact
A section containing the Cretaceous/Paleogene (= Cretaceous/Tertiary) boundary in Monmouth County, New Jersey, preserves a record of ammonites extending from the end of the Cretaceous into possibly the beginning of the Danian. The section includes the upper part of the Tinton Formation and lower part of the Hornerstown Formation. The top of the Tinton Formation is represented by a richly
Authors
Neil H. Landman, Matthew P. Garb, Remy Rovelli, Denton S. Ebel, Lucy E. Edwards
Standardizing texture and facies codes for a process-based classification of clastic sediment and rock Standardizing texture and facies codes for a process-based classification of clastic sediment and rock
Proposed here is a universally applicable, texturally based classification of clastic sediment that is independent from composition, cementation, and geologic environment, is closely allied to process sedimentology, and applies to all compartments in the source-to-sink system. The classification is contingent on defining the term "clastic" so that it is independent from composition or...
Authors
K.M. Farrell, W.B. Harris, D. J. Mallinson, S.J. Culver, S.R. Riggs, J. Pierson, J.C. Lautier
Calcareous nannofossil assemblage changes across the Paleocene-Eocene thermal maximum: Evidence from a shelf setting Calcareous nannofossil assemblage changes across the Paleocene-Eocene thermal maximum: Evidence from a shelf setting
Biotic response of calcareous nannoplankton to abrupt warming across the Paleocene/Eocene boundary reflects a primary response to climatically induced parameters including increased continental runoff of freshwater, global acidification of seawater, high sedimentation rates, and calcareous nannoplankton assemblage turnover. We identify ecophenotypic nannofossil species adapted to low pH...
Authors
Jean M. Self-Trail, David S. Powars, David K. Watkins, Gregory A. Wandless
Ages of pre-rift basement and synrift rocks along the conjugate rift and transform margins of the Argintine Precordillera and Laurentia Ages of pre-rift basement and synrift rocks along the conjugate rift and transform margins of the Argintine Precordillera and Laurentia
New geochronologic data from basement rocks support the interpretation that the Argentine Precordillera (Cuyania) terrane was rifted from the Ouachita embayment of the Iapetan margin of Laurentia. New data from the Ozark dome show a range of ages in two groups at 1466 ± 3 to 1462 ± 1 Ma and 1323 ± 2 to 1317 ± 2 Ma, consistent with existing data for the Eastern Granite-Rhyolite province...
Authors
William A. Thomas, Robert D. Tucker, Ricardo A. Astini, Rodger E. Denison
Digital outcrop model of stratigraphy and breccias of the southern Franklin Mountains, El Paso, Texas Digital outcrop model of stratigraphy and breccias of the southern Franklin Mountains, El Paso, Texas
This chapter reviews and synthesizes the lithostratigraphy, biostratigraphy, chronostratigraphy, and breccia types of the southwestern part of the great American carbonate bank in the southern Franklin Mountains (SFM), El Paso, Texas. Primary stratigraphic units of focus are the Lower Ordovician El Paso and Upper Ordovician Montoya Groups. These groups preserve breccias formed by...
Authors
Jerome A. Bellian, Charles Kerans, John E. Repetski
Magnetostratigraphy susceptibility for the Guadalupian Series GSSPs (Middle Permian) in Guadalupe Mountains National Park and adjacent areas in West Texas Magnetostratigraphy susceptibility for the Guadalupian Series GSSPs (Middle Permian) in Guadalupe Mountains National Park and adjacent areas in West Texas
Here we establish a magnetostratigraphy susceptibility zonation for the three Middle Permian Global boundary Stratotype Sections and Points (GSSPs) that have recently been defined, located in Guadalupe Mountains National Park, West Texas, USA. These GSSPs, all within the Middle Permian Guadalupian Series, define (1) the base of the Roadian Stage (base of the Guadalupian Series), (2) the...
Authors
Bruce R. Wardlaw, Brooks B. Ellwood, Lance L. Lambert, Jonathan H. Tomkin, Gordon L. Bell, Galina P. Nestell
The Middle Ordovician Knox unconformity in the Black Warrior Basin The Middle Ordovician Knox unconformity in the Black Warrior Basin
Analysis of well core and cuttings from the Black Warrior Basin in Mississippi reveals the presence of a Middle Ordovician (Whiterockian) erosional unconformity interpreted to be equivalent to the well-known Knox-Beekmantown unconformity in eastern North America. The unconformity occurs at the top of a peritidal dolostone unit known informally as the upper dolostone, whose stratigraphic...
Authors
Gary S. Dwyer, John E. Repetski
Cambrian-lower Middle Ordovician passive carbonate margin, southern Appalachians Cambrian-lower Middle Ordovician passive carbonate margin, southern Appalachians
The southern Appalachian part of the Cambrian–Ordovician passive margin succession of the great American carbonate bank extends from the Lower Cambrian to the lower Middle Ordovician, is as much as 3.5 km (2.2 mi) thick, and has long-term subsidence rates exceeding 5 cm (2 in.)/k.y. Subsiding depocenters separated by arches controlled sediment thickness. The succession consists of five
Authors
J. Fred Read, John E. Repetski
Fold-to-fault progression of a major thrust zone revealed in horses of the North Mountain fault zone, Virginia and West Virginia, USA Fold-to-fault progression of a major thrust zone revealed in horses of the North Mountain fault zone, Virginia and West Virginia, USA
The method of emplacement and sequential deformation of major thrust zones may be deciphered by detailed geologic mapping of these important structures. Thrust fault zones may have added complexity when horse blocks are contained within them. However, these horses can be an important indicator of the fault development holding information on fault-propagation folding or fold-to-fault...
Authors
Randall C. Orndorff
Dinocyst taphonomy, impact craters, cyst ghosts, and the Paleocene-Eocene thermal maximum (PETM) Dinocyst taphonomy, impact craters, cyst ghosts, and the Paleocene-Eocene thermal maximum (PETM)
Dinocysts recovered from sediments related to the Chesapeake Bay impact structure in Virginia and the earliest Eocene suboxic environment in Maryland show strange and intriguing details of preservation. Features such as curled processes, opaque debris, breakage, microborings and cyst ghosts, among others, invite speculation about catastrophic depositional processes, rapid burial and...
Authors
Lucy E. Edwards
Antarctic and Southern Ocean influences on Late Pliocene global cooling Antarctic and Southern Ocean influences on Late Pliocene global cooling
The influence of Antarctica and the Southern Ocean on Late Pliocene global climate reconstructions has remained ambiguous due to a lack of well-dated Antarctic-proximal, paleoenvironmental records. Here we present ice sheet, sea-surface temperature, and sea ice reconstructions from the ANDRILL AND-1B sediment core recovered from beneath the Ross Ice Shelf. We provide evidence for a major...
Authors
Robert McKay, Tim Naish, Lionel Carter, Christina Riesselman, Robert Dunbar, Charlotte Sjunneskog, Diane Winter, Francesca Sangiorgi, Courtney Warren, Mark Pagani, Stefan Schouten, Veronica Willmott, Richard Levy, Robert DeConto, Ross D. Powell
Igneous activity, metamorphism, and deformation in the Mount Rogers area of SW Virginia and NW North Carolina: A geologic record of Precambrian tectonic evolution of the southern Blue Ridge Province Igneous activity, metamorphism, and deformation in the Mount Rogers area of SW Virginia and NW North Carolina: A geologic record of Precambrian tectonic evolution of the southern Blue Ridge Province
Mesoproterozoic basement in the vicinity of Mount Rogers is characterized by considerable lithologic variability, including major map units composed of gneiss, amphibolite, migmatite, meta-quartz monzodiorite and various types of granitoid. SHRIMP U-Pb geochronology and field mapping indicate that basement units define four types of occurrences, including (1) xenoliths of ca. 1.33 to ≥1...
Authors
Richard P. Tollo, John N. Aleinikoff, Roland Mundil, C. Scott Southworth, Michael A. Cosca, Douglas W. Rankin, Allison E. Rubin, Adrienne Kentner, Christopher A. Parendo, Molly S. Ray