Olsson, Richard K. (2006): The Late Cretaceous/early Paleogene record at Bass River borehole, New Jersey coastal plain

Leg/Site/Hole:
Identifier:
2010-038013
georefid

Creator:
Olsson, Richard K.
Rutgers University, Department of Geological Sciences, Piscataway, NJ, United States
author

Identification:
The Late Cretaceous/early Paleogene record at Bass River borehole, New Jersey coastal plain
2006
In: Anonymous, Geological Society of America, 2006 annual meeting
Geological Society of America (GSA), Boulder, CO, United States
38
7
400
At the Bass River Borehole (New Jersey Coastal Plain Drilling Project, ODP Leg 174AX) the Cretaceous/Paleogene boundary (K/P) lies within an unconformity-bounded, depositional sequence (age ca. 69.1 to 64.5 Ma). A 6-cm-thick spherule layer that contains shocked minerals and an iridium anomaly within this sequence marks the K/P boundary. Calcareous planktonic biostratigraphy indicates that sedimentation was continuous across the K/P and benthic foraminiferal biofacies indicate that relative sea-level fell from 100-150 m above present sea-level in the lower part of the sequence (transgressive systems tract) to ca. 50 m (highstand systems tract) across the K/P. Three significant events are inferred from the depositional record: 1) The K/P event caused by an asteroid impact at Chicxulub, Mexico, 2) a tsunami event following the ballistic fallout of tektites from the Chicxulub ejecta vapor cloud, possibly triggered by massive slumping on the Atlantic slope, and 3) a approximately 5 degrees C warming of sea-surface temperatures related to the main outpouring of the Deccan Traps in India that began about 500 k.y. and ended about 22 k.y. before the K/P. There is no relationship between the first two events and sea-level change during K/P deposition. The third event probably led to a slight rise in sea-level prior to the K/P due to thermal expansion of ocean waters. Carbon 13 values of benthic and planktonic foraminifera across the K/P show the well-known carbon isotopic shift that indicates a reduction in oceanic primary productivity, the "Strangelove" ocean. Oxygen 18 values of early Paleogene (Danian) planktonic species indicate that they occupied a narrow range in the water column, suggesting a thin, restricted deep chlorophyll maximum (DCM) layer. Post Danian oxygen 18 values show that a greater vertical range of the water column was used by a greater diversity of species with shallow, intermediate, and deeper-dwelling habitats, indicating a return to pre-K/P oceanic fertility conditions. Abstract 109476 modified by 128.6.77.212 on 6-29-2006
English
Coverage:Geographic coordinates:
North:75.0000
West:-80.0000East: 20.0000
South:0.0000

Stratigraphy; Atlantic Coastal Plain; Atlantic Ocean; Bass River; Cenozoic; Cretaceous; geochemical anomalies; iridium; isotope ratios; isotopes; K-T boundary; Leg 174AX; lower Paleocene; lower Paleogene; Mesozoic; metals; New Jersey; North Atlantic; Northwest Atlantic; O-18/O-16; Ocean Drilling Program; oxygen; paleo-oceanography; Paleocene; Paleogene; paleotemperature; platinum group; sea-surface temperature; spherules; stable isotopes; stratigraphic boundary; Tertiary; United States; Upper Cretaceous;

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