Onset of the Mid-Cretaceous greenhouse in the Barremian-Aptian; igneous events and the biological, sedimentary, and geochemical responses

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doi: 10.1029/1999PA900040
Author(s): Larson, Roger L.; Erba, Elisabetta
Author Affiliation(s): Primary:
University of Rhode Island, Graduate School of Oceanography, Narragansett, RI, United States
Volume Title: Paleoceanography
Source: Paleoceanography, 14(6), p.663-678. Publisher: American Geophysical Union, Washington, DC, United States. ISSN: 0883-8305 CODEN: POCGEP
Note: In English. 82 refs.; illus., incl. strat. cols., 2 tables, sketch maps
Summary: Basalts and biostratigraphy dated at 125-120 Ma from the Ontong Java and Manihiki Plateaus in the western Pacific evidence the largest volcanic event in Earth history in at least the past 160 m.y. The intervening Nova-Canton Trough rifted at about 121-118 Ma, and a number of guyots and seamounts formed concurrently or slightly later. Geological events that probably were responses to these volcanic/tectonic events occurred in the following chronostratigraphic order. Biotic fluctuations began at about 122.5 Ma. At about 122.0 Ma, 87Sr/86Sr began to decline slowly. Metal concentrations of Co, Mn, Pb, Yb, and Cu in sediments peaked at about 121.5-121.2 Ma. Changes in planktonic communities and sedimentation culminated in a nannoconid "crisis" just prior to 120.5 Ma and in the Selli black shale (OAE la) at about 120.5-119.5 Ma. A sharp drop in δ13C occurred at the beginning of the Selli event and rebounded into a longer positive excursion that reached a peak after the Selli event at about 119.5-118.5 Ma. At 120.5 Ma, 87Sr/86Sr declined rapidly and reached a minimum at about 116-113 Ma. We speculate that the intensity of these latter responses suggests a corresponding peak in volcanic/tectonic activity at about 121-119 Ma. Copyright 1999 by the American Geophysical Union.
Year of Publication: 1999
Research Program: ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Alkaline earth metals; Aptian; Barremian; Basalts; Biostratigraphy; C-13/C-12; Carbon; Chronostratigraphy; Cretaceous; East Pacific; Geochemistry; Igneous rocks; Isotope ratios; Isotopes; Lower Cretaceous; Manihiki Plateau; Mesozoic; Metals; Middle Cretaceous; Nova-Canton Trough; Ontong Java Plateau; Pacific Ocean; Paleoenvironment; South Pacific; Southeast Pacific; Sr-87/Sr-86; Stable isotopes; Strontium; Volcanic rocks; Volcanism; West Pacific
Record ID: 2000031739
Copyright Information: GeoRef, Copyright 2017 American Geosciences Institute.

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