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  1. Book ; Online: Palaeoclimatic control of Upper Pliocene Discoaster assemblages in the North Atlantic

    Chepstow-Lusty, Alex / Backman, Jan / Shackleton, Nicholas J.

    eISSN: 2041-4978

    2018  

    Abstract: Abundance variations of six Pliocene species of the nannofossil genus Discoaster were analyzed over the time interval 1.89–2.95 Ma at five sites in the North Atlantic; DSDP 552 (56°N), DSDP 607 (41°N), ODP 659 (18°N), ODP 658 (20°N) and ODP 662 (1°S). ... ...

    Abstract Abundance variations of six Pliocene species of the nannofossil genus Discoaster were analyzed over the time interval 1.89–2.95 Ma at five sites in the North Atlantic; DSDP 552 (56°N), DSDP 607 (41°N), ODP 659 (18°N), ODP 658 (20°N) and ODP 662 (1°S). Individual species are compared between the five sites as a percentage of the total Discoaster assemblage, using age models based mainly on Discoaster datums (3 control points used at each site). The sampling interval is approximately 3 kyrs. Discoaster brouweri , the only species covering the complete time interval became a less significant component of the assemblages with increasing latitude during the interval prior to 2.3 Ma. Discoaster triradiatus shows a distinct abundance acme at all sites between 1.89–2.7 Ma. Discoaster surculus increased in relative abundance with higher latitudes and upwelling conditions (ODP Site 658). Discoaster pentaradiatus is an important component of the assemblages at all sites, but displays an inverse abundance relationship with D. surculus as a function of increasing latitude and upwelling conditions. Discoaster tamalis and Discoaster asymmetricus are reduced at low latitudes and in upwelling conditions and increase relative to D. brouweri at higher latitudes, where there is strong evidence for taxonomic affinity.
    Subject code 551
    Language English
    Publishing date 2018-09-27
    Publishing country de
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Book ; Online: Age determination and stable carbon oxygen isotopes of sediment core MD99-2334, supplementary data to: Skinner, L C; Shackleton, Nicholas J (2004): Rapid transient changes in northeast Atlantic deep water ventilation age across Termination I. Paleoceanography, 19, PA2005

    Skinner, L C / Shackleton, Nicholas J

    2004  

    Abstract: A sequence of accelerator mass spectrometry (AMS) 14C dates performed on benthic and planktonic foraminifera from a northeast Atlantic deep-sea core (MD99-2334K; 37?48'N, 10?10'W; 3146 m) permit the reconstruction of deep water "14C ventilation ages" ... ...

    Abstract A sequence of accelerator mass spectrometry (AMS) 14C dates performed on benthic and planktonic foraminifera from a northeast Atlantic deep-sea core (MD99-2334K; 37?48'N, 10?10'W; 3146 m) permit the reconstruction of deep water "14C ventilation ages" across the last deglaciation. The records from MD99-2334K have been placed on the GISP2 timescale via the synchrony of temperature changes recorded in the Greenland ice cores and in North Atlantic planktonic delta18O(cc) (calcite delta18O). On the basis of a range of estimates for past source water Delta14C, this permits the estimation of 14C projection ventilation ages for comparison with benthic-planktonic 14C age differences. Although the accurate estimation of past ventilation ages is precluded by unknown deep water Delta14C source signatures, and by uncertainty regarding the extent of deep water mixing, it is clear that deep water ventilation in the northeast Atlantic was significantly reduced during the last glaciation, increased abruptly coincident with the B?lling-Aller?d warming, and rapidly became reduced again during the Younger Dryas cold reversal. The character of these changes is consistent with a varying dominance of North Atlantic Deep Water (NADW) versus Antarctic Bottom Water (AABW). Parallel benthic delta13C, deep water temperature (T(dw)), and deep water delta18O (delta18O(dw)) estimates support this inference. The fact that deglacial changes in the deep water radiocarbon content of the northeast Atlantic run parallel to opposite changes in atmospheric radiocarbon content, and in parallel with Greenland temperature fluctuations, unequivocally implicates changes in ocean circulation in deglacial climate evolution and illustrates the capacity for the deep ocean to respond and contribute to abrupt climate change.
    Language English
    Dates of publication 2004-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1029/2003PA000983
    DOI 10.1594/PANGAEA.738036
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  3. Book ; Online: Nannofossil assemblages of mid-Pliocene sediments from the equatorial Atlantic, supplementary data to: Gibbs, Samantha; Shackleton, Nicholas J; Young, Jeremy R (2004): Orbitally forced climate signals in mid-Pliocene nannofossil assemblages. Marine Micropaleontology, 51(1-2), 39-56

    Shackleton, Nicholas J / Gibbs, Samantha / Young, Jeremy R

    2004  

    Abstract: Downcore cyclic variation in high-resolution nannofossil abundance records from mid-Pliocene equatorial Atlantic ODP Sites 662 and 926 demonstrate the direct response by several Pliocene taxa (notably Discoaster, Sphenolithus and Florisphaera profunda) ... ...

    Abstract Downcore cyclic variation in high-resolution nannofossil abundance records from mid-Pliocene equatorial Atlantic ODP Sites 662 and 926 demonstrate the direct response by several Pliocene taxa (notably Discoaster, Sphenolithus and Florisphaera profunda) to orbitally forced climatic variation. In particular, these records display strong obliquity and precessional signals reflecting primarily high latitude, Southern hemisphere changes influencing upwelling intensity and local low-latitude, insolation-driven climatic changes (via the productivity and/or turbidity influence of Amazon-sourced terrigenous material) at Sites 622 and 926 respectively. In seasonal studies of coccolithophorid assemblages, only part of the variation observed can be explained by abiotic processes, so it is perhaps not surprising that in this study few Pliocene nannofossil taxa demonstrate significant correlations with each other or with physical environmental parameters. Only some variance in nannofossil abundances can be explained by the primary controls of temperature and productivity. The rest is attributed to nonlinear responses to climatic changes; biotic processes such as grazing, predation, viral infection and competition, and/or, abiotic factors for which there is no readily available proxy (e.g. salinity). The lack of strong, consistent intra- and inter-relationships of the nannoflora and the environment reflects an ecologically complex, differentiated original community producing a complex integrated signal transmitted into the fossil record.
    Language English
    Dates of publication 2004-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1016/j.marmicro.2003.09.002
    DOI 10.1594/PANGAEA.676965
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  4. Book ; Online: Stable carbon and oxygen isotope ratios of foraminifera from the latest Miocene to earliest Pliocene of Ceare Rise, western tropical Atlantic, supplementary data to: Pfuhl, Helen A; Shackleton, Nicholas J (2004): Changes in coiling direction, habitat depth and abundance in two menardellid species. Marine Micropaleontology, 50(1-2), 3-20

    Pfuhl, Helen A / Shackleton, Nicholas J

    2004  

    Abstract: We present a detailed study of menardellid speciation, abundance and coiling changes between 6.34 and 5.1 Ma (latest Miocene and earliest Pliocene). Menardellids are widely distributed in tropical to subtropical waters from Miocene to modern time, ... ...

    Abstract We present a detailed study of menardellid speciation, abundance and coiling changes between 6.34 and 5.1 Ma (latest Miocene and earliest Pliocene). Menardellids are widely distributed in tropical to subtropical waters from Miocene to modern time, revealing a stable isotopic signature characteristic for the top of the thermocline and shallower rather than deeper habitat depth. Menardellid response to its environment reveals a tripartite pattern. The first interval from ~6.34 to 5.75 Ma is marked by a dominance of Menardella limbata, frequent changes in coiling direction, and variable abundance with strongest reductions during intervals of dextral dominance. The onset of an interval of cooling and ice build-up at 5.82 Ma coincides with a weakening of the mixed layer leading to nearly 70 kyr of strongly reduced menardellid abundance. At 5.75 Ma, Menardella multicamerata replaces M. limbata as the prevailing menardellid species, at the same time as the overall abundance of menardellids stabilises. Initial stabilisation of sinistral coiling until the end of the cold interval at ~5.49 Ma suggests the development of a temperature preference in sinistral (cold) and dextral (warm) M. multicamerata. A strong increase in menardellid delta13C values relative to the thermocline gradient (difference between the delta18O records of surface-dwelling Globigerinoides trilobus and Menardella spp.) following 5.77 Ma suggests a move to shallower habitat depths of both M. multicamerata morphotypes. Initiated by mixed layer destabilisation, both the development of a temperature preference and the move to shallower habitat depth in M. multicamerata appear to identify its adjustment to a new niche driving the replacement of M. limbata as the dominant menardellid species.
    Language English
    Dates of publication 2004-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1016/S0377-8398(03)00063-X
    DOI 10.1594/PANGAEA.678283
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  5. Book ; Online: Sea surface temperature estimation for the Iberian Margin, supplementary data to: Martrat, Belen; Grimalt, Joan O; Shackleton, Nicholas J; de Abreu, Lucia; Hutterli, Manuel A; Stocker, Thomas F (2007): Four climate cycles of recurring deep and surface water destabilizations on the Iberian Margin. Science, 317(5837), 502-507

    Martrat, Belen / Grimalt, Joan O / Hutterli, Manuel A / Shackleton, Nicholas J / Stocker, Thomas F / de Abreu, Lucia

    2011  

    Abstract: Centennial climate variability over the last ice age exhibits clear bipolar behavior. High-resolution analyses of marine sediment cores from the Iberian margin trace a number of associated changes simultaneously. Proxies of sea surface temperature and ... ...

    Abstract Centennial climate variability over the last ice age exhibits clear bipolar behavior. High-resolution analyses of marine sediment cores from the Iberian margin trace a number of associated changes simultaneously. Proxies of sea surface temperature and water mass distribution, as well as relative biomarker content, demonstrate that this typical north-south coupling was pervasive for the cold phases of climate during the past 420,000 years. Cold episodes after relatively warm and largely ice-free periods occurred when the predominance of deep water formation changed from northern to southern sources. These results reinforce the connection between rapid climate changes at Mediterranean latitudes and century-to-millennial variability in northern and southern polar regions.
    Language English
    Dates of publication 2011-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1126/science.1139994
    DOI 10.1594/PANGAEA.771894
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  6. Book ; Online: Deep-water temperature reconstruction of sediment core MD99-2334, supplementary data to: Skinner, L C; Shackleton, Nicholas J; Elderfield, Harry (2003): Millennial-scale variability of deep-water temperature and d18Odw indicating deep-water source variations in the Northeast Atlantic, 0-34 cal. ka BP. Geochemistry, Geophysics, Geosystems, 4(12)

    Skinner, L C / Elderfield, Harry / Shackleton, Nicholas J

    2003  

    Abstract: Paired measurements of Mg/Ca and delta18O(cc) (calcite delta18O) in benthic foraminifera from a deep-sea core recovered on the Iberian Margin (MD99-2334K; 37°48'N, 10°10'W; 3,146 m) have been performed in parallel with planktonic delta18O(cc) analyses ... ...

    Abstract Paired measurements of Mg/Ca and delta18O(cc) (calcite delta18O) in benthic foraminifera from a deep-sea core recovered on the Iberian Margin (MD99-2334K; 37°48'N, 10°10'W; 3,146 m) have been performed in parallel with planktonic delta18O(cc) analyses and counts of ice-rafted debris (IRD). The synchrony of temperature changes recorded in the Greenland ice cores and in North Atlantic planktonic delta18O(cc) allows the proxy records from MD99-2334K to be placed confidently on the GISP2 time-scale. This correlation is further corroborated by AMS 14C-dates. Benthic Mg/Ca measurements in MD99-2334K permit the reconstruction of past deep-water temperature (T(dw)) changes since ~34 cal. ka BP (calendar kiloyears before present). Using these T(dw) estimates and parallel benthic delta18O(cc) measurements, a record of deep-water delta18O (delta18O(dw)) has been calculated. Results indicate greatly reduced T(dw) in the deep Northeast Atlantic during the last glaciation until ~15 cal. ka BP, when T(dw) warmed abruptly to near-modern values in parallel with the onset of the Bølling-Allerød interstadial. Subsequently, Tdw reverted to cold glacial values between ~13.4 and ~11.4 cal. ka BP, in parallel with the Younger Dryas cold reversal and the H0 ice-rafting event. Similar millennial-scale T(dw) changes also occurred during the last glaciation. Indeed, throughout the last ~34 cal. ka, millennial delta18O(dw) and T(dw) changes have remained well coupled and are linked with IRD pulses coincident with Heinrich events 3, 2, 1, and the Younger Dryas, when transitions to lower T(dw) and delta18O(dw) conditions occurred. In general, millennial T(dw) and delta18O(dw) variations recorded in MD99-2334K describe an alternation between colder, low-delta18O(dw) and warmer, high delta18O(dw) conditions, which suggests the changing local dominance of northern-sourced North Atlantic Deep Water (NADW) versus southern-sourced Antarctic Bottom Water (AABW). The observed similarity of the T(dw) and GISP2 delta18O(ice) records would therefore suggest a common component of variability resulting from the coupling of NADW formation and Greenland climate. A link between Greenland stadials and the incursion of cold, low-delta18O(dw) AABW in the deep Northeast Atlantic is thus implied, which contributes to the relationship between Greenland climate and the millennial benthic delta18O(cc) signal since ~34 cal. ka BP.
    Language English
    Dates of publication 2003-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1029/2003GC000585
    DOI 10.1594/PANGAEA.738090
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  7. Book ; Online: Benthic foraminifera and stable isotope composition in Paleocene-Eocene sediments, supplementary data to: Thomas, Ellen; Shackleton, Nicholas J (1996): The Paleocene-Eocene benthic foraminiferal extinction and stable isotope anomalies. In: Knox, RWO'B; Corfield, RM; Dunay, RE (eds.), Correlation of the Early Paleogene in Northwest Europe, Geological Society Special Publication, 101, 401-441

    Thomas, Ellen / Shackleton, Nicholas J

    1996  

    Abstract: In the late Paleocene to early Eocene, deep sea benthic foraminifera suffered their only global extinction of the last 75 million years and diversity decreased worldwide by 30-50% in a few thousand years. At Maud Rise (Weddell Sea, Antarctica; Sites ... ...

    Abstract : In the late Paleocene to early Eocene, deep sea benthic foraminifera suffered their only global extinction of the last 75 million years and diversity decreased worldwide by 30-50% in a few thousand years. At Maud Rise (Weddell Sea, Antarctica; Sites 689 and 690, palaeodepths 1100 m and 1900 m) and Walvis Ridge (Southeastern Atlantic, Sites 525 and 527, palaeodepths 1600 m and 3400 m) post-extinction faunas were low-diversity and high-dominance, but the dominant species differed by geographical location. At Maud Rise, post-extinction faunas were dominated by small, biserial and triserial species, while the large, thick-walled, long-lived deep sea species Nuttallides truempyi was absent. At Walvis Ridge, by contrast, they were dominated by long-lived species such as N. truempyi, with common to abundant small abyssaminid species. The faunal dominance patterns at the two locations thus suggest different post-extinction seafloor environments: increased flux of organic matter and possibly decreased oxygen levels at Maud Rise, decreased flux at Walvis Ridge. The species-richness remained very low for about 50 000 years, then gradually increased.
    The extinction was synchronous with a large, negative, short-term excursion of carbon and oxygen isotopes in planktonic and benthic foraminifera and bulk carbonate. The isotope excursions reached peak negative values in a few thousand years and values returned to pre-excursion levels in about 50 000 years. The carbon isotope excursion was about -2 per mil for benthic foraminifera at Walvis Ridge and Maud Rise, and about -4 per mil for planktonic foraminifera at Maud Rise. At the latter sites vertical gradients thus decreased, possibly at least partially as a result of upwelling. The oxygen isotope excursion was about -1.5 per mil for benthic foraminifera at Walvis Ridge and Maud Rise, -1 per mil for planktonic foraminifera at Maud Rise.
    The rapid oxygen isotope excursion at a time when polar ice-sheets were absent or insignificant can be explained by an increase in temperature by 4-6°C of high latitude surface waters and deep waters world wide. The deep ocean temperature increase could have been caused by warming of surface waters at high latitudes and continued formation of the deep waters at these locations, or by a switch from dominant formation of deep waters at high latitudes to formation at lower latitudes. Benthic foraminiferal post-extinction biogeographical patterns favour the latter explanation.
    The short-term carbon isotope excursion occurred in deep and surface waters, and in soil concretions and mammal teeth in the continental record. It is associated with increased CaC03-dissolution over a wide depth range in the oceans, suggesting that a rapid transfer of isotopically light carbon from lithosphere or biosphere into the ocean-atmosphere system may have been involved. The rapidity of the initiation of the excursion (a few thousand years) and its short duration (50 000 years) suggest that such a transfer was probably not caused by changes in the ratio of organic carbon to carbonate deposition or erosion. Transfer of carbon from the terrestrial biosphere was probably not the cause, because it would require a much larger biosphere destruction than at the end of the Cretaceous, in conflict with the fossil record. It is difficult to explain the large shift by rapid emission into the atmosphere of volcanogenic CO2, although huge subaerial plateau basalt eruptions occurred at the time in the northern Atlantic. Probably a complex combination of processes and feedback was involved, including volcanogenic emission of CO2, changing circulation patterns, changing productivity in the oceans and possibly on land, and changes in the relative size of the oceanic and atmospheric carbon reservoirs.
    Language English
    Dates of publication 1996-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1144/GSL.SP.1996.101.01.20
    DOI 10.1594/PANGAEA.770123
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  8. Book ; Online: Stable carbon and oxygen isotope ratios of foraminifera from sediments of the Iberian margin, supplementary data to: Shackleton, Nicholas J; Hall, Michael A; Vincent, Edith (2000): Phase relationships between millennial-scale events 64,000-24,000 years ago. Paleoceanography, 15(6), 565-569

    Shackleton, Nicholas J / Hall, Michael A / Vincent, Edith

    2000  

    Abstract: A core recovered on the Iberian margin off southern Portugal can be correlated with Greenland ice cores using oxygen isotope variability in planktonic foraminifera which closely matches the ice core records of temperature over Greenland. Our age model ... ...

    Abstract A core recovered on the Iberian margin off southern Portugal can be correlated with Greenland ice cores using oxygen isotope variability in planktonic foraminifera which closely matches the ice core records of temperature over Greenland. Our age model identifies the base of every interstadial between 64,000 and 24,000 years ago and uses the Greenland Ice Core Project (GRIP) timescale. The oxygen isotope signal in benthic foraminifera (on this GRIP-based timescale) is quite different from the planktonic record and resembles the temperature record over Antarctica when this is synchronized with Greenland using the record of methane in the atmospheric air in the polar ice cores. We interpret the benthic record as indicating significant fluctuations in ice volume during millennial events, and we suggest that Antarctic temperature changed as a function of ice volume.
    Language English
    Dates of publication 2000-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1029/2000PA000513
    DOI 10.1594/PANGAEA.700954
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  9. Article: Evidence of 550-year and 1000-year cyclicities in North Atlantic circulation patterns during the Holocene

    Chapman, Mark R / Shackleton, Nicholas J

    Holocene. 2000 Apr., v. 10, no. 3

    2000  

    Abstract: Sedimentological colour data obtained from North Atlantic deep-sea sediment core NEAP15K pro vide a continuous climate record for the last 11500 yr with a mean sampling interval of <15 yr. Variations in sediment lightness, a proxy for changes in North ... ...

    Abstract Sedimentological colour data obtained from North Atlantic deep-sea sediment core NEAP15K pro vide a continuous climate record for the last 11500 yr with a mean sampling interval of <15 yr. Variations in sediment lightness, a proxy for changes in North Atlantic Deep Water (NADW) circulation, are characterized by high-frequency fluctuations with periodicities equivalent to 550 and 1000 yr, as well as a <1600-yr cyclicity comparable to that reported in other studies of Holocene climate. Cross-spectral analysis suggests that the 550-yr and 1000-yr cyclical variations in NADW circulation were coherent with fluctuations in atmospheric con ditions over Greenland, where both these periodicities have been identified previously in the Holocene GISP2 d18O record (Stuiver et al., 1995). A similar statistical comparison provides evidence that high-frequency (550-yr) variability in NADW circulation patterns may have been linked to short-term variations in atmospheric 14C values during the Holocene. In general, NADW production was lower and 14C levels were higher when colder climatic conditions prevailed. These results imply that the pattern of NADW production has been a significant factor affecting centennial-to millennial-scale Holocene climate variability in the North Atlantic region.
    Keywords carbon ; climatic factors ; color ; marine sediments ; meteorological data ; periodicity ; radionuclides ; Greenland
    Language English
    Dates of publication 2000-04
    Size p. 287-291.
    Publishing place Sage Publications
    Document type Article
    ZDB-ID 2027956-5
    ISSN 1477-0911 ; 0959-6836
    ISSN (online) 1477-0911
    ISSN 0959-6836
    DOI 10.1191/095968300671253196
    Database NAL-Catalogue (AGRICOLA)

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  10. Book ; Online: Age model tie points of ODP Sites in the central Atlantic Ocean, supplementary data to: Gibbs, Samantha; Young, Jeremy R; Bralower, Timothy J; Shackleton, Nicholas J (2007): Nannofossil evolutionary events in the mid-Pliocene: an assessment of the degree of synchrony in the extinctions of Reticulofenestra pseudoumbilicus and Sphenolithus abies. Palaeogeography, Palaeoclimatology, Palaeoecology, 217(1-2), 155-172

    Gibbs, Samantha / Bralower, Timothy J / Shackleton, Nicholas J / Young, Jeremy R

    2005  

    Abstract: The mid-Pliocene was an interval of subtle reorganisation within the nannoplankton community, including the prominent and biostratigraphically important last occurrences of Sphenolithus abies and Reticulofenestra pseudoumbilicus. The transition is part ... ...

    Abstract The mid-Pliocene was an interval of subtle reorganisation within the nannoplankton community, including the prominent and biostratigraphically important last occurrences of Sphenolithus abies and Reticulofenestra pseudoumbilicus. The transition is part of the Pliocene to Recent "attrition" of nannofossil species that resulted from changes in the distribution of trophic resources, and deep-water and surface-water current systems, likely associated with the initiation of Northern Hemisphere glaciation.
    The extinctions of Sphenolithus abies and Reticulofenestra pseudoumbilicus were analysed in detail at ODP Sites 659, 662, and 926 in the equatorial and subequatorial Atlantic. These taxa show significantly different patterns of duration and timing of decline based on high-resolution abundance records and calibration with oxygen isotope stratigraphy. The initiation of abundance decline between 3.71 and 3.67 Ma and the extinction of S. abies between 3.56 and 3.52 Ma are diachronous. This extinction may have been a response to the intensification of glacial intervals at this time. In contrast, the last occurrence of R. pseudoumbilicus at 3.81-3.82 Ma appears to be a valid example of biostratigraphic (although not necessarily biological) synchrony in the fossil record. Direct environmental forcing is not attributable for the extinction of R. pseudoumbilicus; however, indirect physical and/or biological environmental stress may explain the observed patterns.
    Language English
    Dates of publication 2005-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1016/j.palaeo.2004.11.005
    DOI 10.1594/PANGAEA.694086
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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