Paleoceanography
1944-9186
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Các bài báo tiêu biểu
A Pliocene‐Pleistocene stack of 57 globally distributed benthic δ18O recordsWe present a 5.3‐Myr stack (the “LR04” stack) of benthic δ18 O records from 57 globally distributed sites aligned by an automated graphic correlation algorithm. This is the first benthic δ18 O stack composed of more than three records to extend beyond 850 ka, and we use its improved signal quality to identify 24 new marine isotope stages in the early... ...
Tập 20 Số 1 - 2005
Glacial‐interglacial CO2 change: The Iron HypothesisSeveral explanations for the 200 to 280 ppm glacial/interglacial change in atmospheric CO2 concentrations deal with variations in southern ocean phytoplankton productivity and the related use or nonuse of major plant nutrients. An hypothesis is presented herein in which arguments are made that new productivity in today's southern ocean (7.4 × 1013 g... ...
Tập 5 Số 1 - Trang 1-13 - 1990
Deepwater source variations during the last climatic cycle and their impact on the global deepwater circulationThe degree of similarity of the ∂13 C records of the planktonic foraminiferal speciesN. pachyderma and of the benthic foraminiferal genusCibicides in the high‐latitude basins of the world ocean is used as an indicator of the presence of deepwater sources during the last climatic cycle. Whereas continuous formation of d... ...
Tập 3 Số 3 - Trang 343-360 - 1988
Astronomic timescale for the Pliocene Atlantic δ18O and dust flux records of Ocean Drilling Program Site 659High‐resolution benthic oxygen isotope and dust flux records from Ocean Drilling Program site 659 have been analyzed to extend the astronomically calibrated isotope timescale for the Atlantic from 2.85 Ma back to 5 Ma. Spectral analysis of the δ18 O record indicates that the 41‐kyr period of Earth's orbital obliquity dominates the Pliocene record. This is shown to be tr... ...
Tập 9 Số 4 - Trang 619-638 - 1994
Application of the Ce anomaly as a paleoredox indicator: The ground rulesMuch attention has been paid, in recent years, to the potential application of the Ce anomaly, measured in various marine phases, as a paleoceanographic indicator of widespread marine anoxia. In this paper we present and discuss results from recent studies of present‐day rare earth element (REE) distributions (and hence Ce anomaly distributions) in the marine environment which are particul... ...
Tập 5 Số 5 - Trang 823-833 - 1990
The timing of major climate terminationsA simple, untuned “constant sedimentation rate” timescale developed using three radiometric age constraints and eleven δ18 O records longer than 0.8 Myr provides strong support for the validity of the SPECMAP timescale of the late Quaternary [Imbrie et al., 1984]. In particular, the present study independently confirms the link between major d... ...
Tập 12 Số 4 - Trang 577-585 - 1997
El Niño variability off Peru during the last 20,000 yearsHere we present a high‐resolution marine sediment record from the El Niño region off the coast of Peru spanning the last 20,000 years. Sea surface temperature, photosynthetic pigments, and a lithic proxy for El Niño flood events on the continent are used as paleo–El Niño–Southern Oscillation proxy data. The onset of stronger El Niño activity in Peru started around 17,000 calibrated years b... ...
Tập 20 Số 4 - 2005
Nannofossils and superplumes: The Early Aptian “nannoconid crisis”A group of calcareous nannoplankton named nannoconids experienced a crisis in the early Aptian and recovered only later in the late Aptian after a period of virtual absence. Although no extinctions occurred, the widespread nature of the “nannoconid crisis” suggests a global causal factor. This crisis is recorded within the Chiastozygus litterarius nannofossil and... ...
Tập 9 Số 3 - Trang 483-501 - 1994
The 41 kyr world: Milankovitch's other unsolved mysteryFor most of the Northern Hemisphere Ice Ages, from ∼3.0 to 0.8 m.y., global ice volume varied predominantly at the 41,000 year period of Earth's orbital obliquity. However, summer (or summer caloric half year) insolation at high latitudes, which is widely believed to be the major influence on high‐latitude climate and ice volume, is dominated by the 23,000 year precessional period. Thus th... ...
Tập 18 Số 1 - 2003
Enhanced productivity led to increased organic carbon burial in the euxinic North Atlantic basin during the late Cenomanian oceanic anoxic eventThree Cenomanian/Turonian (C/T, ∼93.5 Ma) black shale sections along a northeast‐southwest transect in the southern part of the proto‐North Atlantic Ocean were correlated by stable carbon isotope stratigraphy using the characteristic excursion in δ13 C values of both bulk organic matter (OM) and molecular fossils of algal chlorophyll and steroids. All three sites show a... ...
Tập 17 Số 4 - 2002