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  • 2010-2014  (10)
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  • 1
    Publication Date: 2022-05-26
    Description: Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 12 (2011): Q04003, doi:10.1029/2010GC003333.
    Description: Core top samples from Indonesian and northeast Atlantic depth transects were used to calibrate Mg/Ca and δ18O in tests of the calcitic benthic foraminifer Hyalinea balthica to bottom water temperature between 4°C and 13°C. This shallow infaunal species is primarily abundant in neritic to upper bathyal sediments (〈600 m). Both linear and exponential calibrations suggest a temperature sensitivity of ~12% per °C that is ~4 times higher than observed in other species of deep-sea benthic foraminifera. Culture experiments support the core top calibration. We find no discernible effect of salinity and saturation on Mg/Ca. Comparison between the measured benthic foraminiferal δ18O and predicted equilibrium values suggests that on average H. balthica δ18O is 0.64‰ ± 0.13‰ lower than predicted from the equilibrium composition. To test the reliability of using paired H. balthica Mg/Ca and δ18O measurements for reconstructing seawater δ18Osw and salinity, we apply this calibration to another depth transect from Cape Ghir off NW Africa, which was not included in the calibration. Based on error analysis of the calibration data and this validation test, we show that the uncertainty of reconstructing bottom water temperature and salinity from paired Mg/Ca and δ18O measurements of H. balthica is better than ±0.7°C and ±0.69 practical salinity scale, respectively. The small uncertainties allow for the reconstruction of seawater density to better than 0.3σθ units, which is precise enough for the identification of specific water masses and reconstruction of changes in their properties. We propose that the relatively high Mg content and temperature sensitivity of H. balthica might be due to minor, biologically mediated contribution of high-Mg calcite to the primarily low Mg calcite test, which is influenced by the ambient temperature. This hypothesis, if correct, suggests that benthic species with relatively high Mg/Ca may be better suited for deepwater temperature reconstructions than species that have thus far been more commonly used.
    Description: This project was funded by NSF Awards OCE 02‐20922 and 09‐02977 to YR, OCE 09‐28607 to MK, OCE02‐20776 to DWO, and DFG priority program INTERDYNAMIK to AM.
    Keywords: Mg/Ca ; Benthic foraminifera ; Temperature calibration ; Isotope
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Format: application/pdf
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  • 2
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    PANGAEA
    In:  Supplement to: Katz, Miriam E; Cramer, Benjamin S; Toggweiler, J Robbie; Esmay, Gar; Liu, Chengji; Miller, Kenneth G; Rosenthal, Yair; Wade, Bridget S; Wright, James D (2011): Impact of Antarctic Circumpolar Current development on late Paleogene ocean structure. Science, 332(6033), 1076-7079, https://doi.org/10.1126/science.1202122
    Publication Date: 2024-07-19
    Description: Global cooling and the development of continental-scale Antarctic glaciation occurred in the late middle Eocene to early Oligocene (~38 to 28 million years ago), accompanied by deep-ocean reorganization attributed to gradual Antarctic Circumpolar Current (ACC) development. Our benthic foraminiferal stable isotope comparisons show that a large d13C offset developed between mid-depth (~600 meters) and deep (〉1000 meters) western North Atlantic waters in the early Oligocene, indicating the development of intermediate-depth d13C and O2 minima closely linked in the modern ocean to northward incursion of Antarctic Intermediate Water. At the same time, the ocean's coldest waters became restricted to south of the ACC, probably forming a bottom-ocean layer, as in the modern ocean. We show that the modern four-layer ocean structure (surface, intermediate, deep, and bottom waters) developed during the early Oligocene as a consequence of the ACC.
    Keywords: 171-1053; 171-1053A; ASP-5; Carolina Slope, North Atlantic Ocean; COMPCORE; Composite Core; DRILL; Drilling/drill rig; Joides Resolution; Leg171B; North Atlantic; Ocean Drilling Program; ODP
    Type: dataset publication series
    Format: application/zip, 4 datasets
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  • 3
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    PANGAEA
    In:  Supplement to: Miller, Kenneth G; Browning, James V; Aubry, Marie-Pierre; Wade, Bridget S; Katz, Miriam E; Kulpecz, Andrew A; Wright, James D (2008): Eocene-Oligocene global climate and sea-level changes: St. Stephens Quarry, Alabama. Geological Society of America Bulletin, 120(1/2), 34-53, https://doi.org/10.1130/B26105.1
    Publication Date: 2024-07-19
    Description: We integrate upper Eocene-lower Oligocene lithostratigraphic, magnetostratigraphic, biostratigraphic, stable isotopic, benthic foraminiferal faunal, downhole log, and sequence stratigraphic studies from the Alabama St. Stephens Quarry (SSQ) core hole, linking global ice volume, sea level, and temperature changes through the greenhouse to icehouse transition of the Cenozoic. We show that the SSQ succession is dissected by hiatuses associated with sequence boundaries. Three previously reported sequence boundaries are well dated here: North Twistwood Creek-Cocoa (35.4-35.9 Ma), Mint Spring-Red Bluff (33.0 Ma), and Bucatunna-Chickasawhay (the mid-Oligocene fall, ca. 30.2 Ma). In addition, we document three previously undetected or controversial sequences: mid-Pachuta (33.9-35.0 Ma), Shubuta-Bumpnose (lowermost Oligocene, ca. 33.6 Ma), and Byram-Glendon (30.5-31.7 Ma). An ~0.9 per mil d18O increase in the SSQ core hole is correlated to the global earliest Oligocene (Oi1) event using magnetobiostratigraphy; this increase is associated with the Shubuta-Bumpnose contact, an erosional surface, and a biofacies shift in the core hole, providing a first-order correlation between ice growth and a sequence boundary that indicates a sea-level fall. The d18O increase is associated with a eustatic fall of ~55 m, indicating that ~0.4 per mil of the increase at Oi1 time was due to temperature. Maximum d18O values of Oi1 occur above the sequence boundary, requiring that deposition resumed during the lowest eustatic lowstand. A precursor d18O increase of 0.5 per mil (33.8 Ma, midchron C13r) at SSQ correlates with a 0.5 per mil increase in the deep Pacific Ocean; the lack of evidence for a sea-level change with the precursor suggests that this was primarily a cooling event, not an ice-volume event. Eocene-Oligocene shelf water temperatures of ~17-19 °C at SSQ are similar to modern values for 100 m water depth in this region. Our study establishes the relationships among ice volume, d18O, and sequences: a latest Eocene cooling event was followed by an earliest Oligocene ice volume and cooling event that lowered sea level and formed a sequence boundary during the early stages of eustatic fall.
    Keywords: Alabama, Alabama, U.S.A., North America; DRILL; Drilling/drill rig; SSQ; St-Stephens-Quarry
    Type: dataset publication series
    Format: application/zip, 2 datasets
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  • 4
    Publication Date: 2024-07-19
    Keywords: AGE; ASP-5; Cibicidoides cicatricosus, Magnesium/Calcium ratio; Cibicidoides compressus, Magnesium/Calcium ratio; Cibicidoides crebbsi, Magnesium/Calcium ratio; Cibicidoides mexicanus, Magnesium/Calcium ratio; Cibicidoides pachyderma, Magnesium/Calcium ratio; Cibicidoides praemundulus, Magnesium/Calcium ratio; Cibicidoides spp., Magnesium/Calcium ratio; DEPTH, sediment/rock; DRILL; Drilling/drill rig; Inductively coupled plasma - mass spectrometry (ICP-MS); North Atlantic; Oridorsalis spp., Magnesium/Calcium ratio; Species
    Type: dataset
    Format: text/tab-separated-values, 90 data points
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  • 5
    Publication Date: 2024-07-19
    Keywords: 171-1053A; AGE; Carolina Slope, North Atlantic Ocean; Cibicidoides eocaenus, δ13C; Cibicidoides eocaenus, δ18O; Cibicidoides grimsdalei, δ13C; Cibicidoides grimsdalei, δ18O; Cibicidoides praemundulus, δ13C; Cibicidoides praemundulus, δ18O; Cibicidoides sp., δ13C; Cibicidoides sp., δ18O; Corrected; Depth, composite; DEPTH, sediment/rock; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Intercore correlation; Isotope ratio mass spectrometry; Joides Resolution; Leg171B; Nuttallides truempyi, δ13C; Nuttallides truempyi, δ18O; Ocean Drilling Program; ODP; Sample code/label; Species; δ13C, adjusted/corrected; δ18O, adjusted/corrected
    Type: dataset
    Format: text/tab-separated-values, 337 data points
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  • 6
    Publication Date: 2024-07-19
    Keywords: 171-1053; Age, biostratigraphy; Age model; Age model, Berggren et al (1995) BKSA95; Age model, optional; Ageprofile Datum Description; ASP-5; Carolina Slope, North Atlantic Ocean; COMPCORE; Composite Core; DEPTH, sediment/rock; DRILL; Drilling/drill rig; Event label; Joides Resolution; Leg171B; North Atlantic; Ocean Drilling Program; ODP
    Type: dataset
    Format: text/tab-separated-values, 65 data points
    Location Call Number Limitation Availability
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  • 7
    Publication Date: 2024-07-19
    Keywords: AGE; ASP-5; Cibicidoides aff. praemundulus, δ13C; Cibicidoides aff. praemundulus, δ18O; Cibicidoides cicatricosus, δ13C; Cibicidoides cicatricosus, δ18O; Cibicidoides mexicanus, δ13C; Cibicidoides mexicanus, δ18O; Cibicidoides pachyderma, δ13C; Cibicidoides pachyderma, δ18O; Cibicidoides praemundulus, δ13C; Cibicidoides praemundulus, δ18O; Cibicidoides spp., δ13C; Cibicidoides spp., δ18O; DEPTH, sediment/rock; DRILL; Drilling/drill rig; Isotope ratio mass spectrometry; North Atlantic; Species
    Type: dataset
    Format: text/tab-separated-values, 598 data points
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  • 8
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    PANGAEA
    In:  Supplement to: Miller, Kenneth G; Katz, Miriam E (1987): Eocene benthic foraminiferal biofacies of the New Jersey Transect. In: Poag, CW; Watts, AB; et al. (eds.), Initial Reports of the Deep Sea Drilling Project, Washington (U.S. Govt. Printing Office), 95, 267-298, https://doi.org/10.2973/dsdp.proc.95.107.1987
    Publication Date: 2024-07-22
    Description: Benthic foraminiferal biofacies may vary independently of water depth and water mass; however, calibration of biofacies and stratigraphic ranges with independent paleodepth estimates allows reconstruction of age-depth patterns applicable throughout the deep Atlantic (Tjalsma and Lohmann, 1983). We have attempted to test these faunal calibrations in a continental margin setting, reconstructing Eocene benthic foraminiferal distributions along a dip section afforded by the New Jersey Transect (DSDP Sites 612, 108, 613). The following independent estimates of Eocene depths for the transect were obtained by "backtracking," "backstripping," and by assuming increasing depth downdip ("paleoslope"): Site 612, near the middle/lower bathyal boundary (about 1000 m); Site 108, in the middle bathyal zone (about 1600 m); and Site 613, near the lower bathyal/upper abyssal boundary (about 2000 m). Within uncertainties of backtracking (hundreds of meters), these estimates agree with estimates of paleodepth based on comparison of the New Jersey margin biofacies with other backtracked faunas. The stratigraphic ranges of many benthic taxa correspond to those found at other Atlantic DSDP sites. The major biofacies patterns show: (1) a depth dichotomy between an early to middle Eocene Nuttallides truempyidominated biofacies (greater than 2000 m) and a Lenticulina-Osangularia-Alabamina cf. dissonata biofacies (1000- 2000 m); and (2) a difference between a middle and a late Eocene biofacies at Site 612. The faunal boundary at about 2000 m, between bathyal and abyssal zones, occurs not only on the margin, but also throughout the deep Atlantic. The faunal change between the middle and late Eocene at Site 612 was due to a decrease of Lenticulina spp., the local disappearance of N. truempyi, and establishment of a Bulimina alazanensis-Gyroidinoides spp. biofacies. Although this change could be attributed to local paleoceanographic or water-depth changes, we argue that it is the bathyal expression of a global deep-sea benthic foraminiferal change which occurred across the middle/late Eocene boundary.
    Keywords: Deep Sea Drilling Project; DSDP
    Type: dataset publication series
    Format: application/zip, 2 datasets
    Location Call Number Limitation Availability
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  • 9
    Publication Date: 2024-07-23
    Keywords: 11-108; 95-613; Abyssamina spp.; AGE; Alabamina cf. dissonata; Anomalinoides spp.; Aragonia spp.; Bathysiphon eocenica; Bolivina antegressa; Bulimina alazanensis; Bulimina callahani; Bulimina glomarchallengeri; Bulimina jarvisi; Bulimina macilenta; Bulimina semicostata; Bulimina trinitatensis; Bulimina tuxpamensis; Buliminella grata; Cassidulina havanensis; Cibicidoides bradyi; Cibicidoides cf. pseudoperlucidus; Cibicidoides grimsdalei; Cibicidoides havanensis; Cibicidoides laurisae; Cibicidoides mundulus; Cibicidoides subspiratus; Cibicidoides tuxpamensis; Clinapertina spp.; Counting 〉149 µm fraction; Deep Sea Drilling Project; Dentalina spp.; DEPTH, sediment/rock; DRILL; Drilling/drill rig; DSDP; Eggerella sp.; Elevation of event; Event label; Foraminifera, benthic; Foraminifera, benthic agglutinated; Gaudryina cf. laevigata; Gaudryina cf. pyramidata; Gaudryina pyramidata; Gavelinella capitata; Gavelinella micra; Globocassidulina subglobosa; Glomar Challenger; Gyroidinoides spp.; Hanzawaia ammophila; Karreriella chapapotensis; Karreriella subglabra; Latitude of event; Leg11; Leg95; Lenticulina spp.; Longitude of event; Nonionellina spp.; Nonion spp.; North Atlantic/CONT RISE; North Atlantic/SLOPE; Nuttallides truempyi; Oridorsalis umbonatus; Osangularia spp.; Planulina renzi; Pleurostomella spp.; Pullenia quinqueloba; Quadrimorphina profunda; Sample code/label; Sigmoilopsis sp.; Siphonina sp.; Siphonodosaria gracillima; Spiroplectammina spectabilis; Spirosigmoilinella compressa; Stilostomella subspinosa; Stylodictya aculeata; Trifarina danvillensis; Trifarina sp.; Tritaxia sp.; Turrilina robertsi; Uvigerina basicordata; Uvigerina hispida; Uvigerina rippensis; Vulvulina spinosa
    Type: dataset
    Format: text/tab-separated-values, 520 data points
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  • 10
    Publication Date: 2012-02-01
    Description: The Eocene-Oligocene transition (EOT; ca. 33–34 Ma) was a time of pronounced climatic change, marked by the establishment of continental-scale Antarctic ice sheets. The timing and extent of temperature change associated with the EOT is controversial. Here we present multiproxy EOT climate records (~15–34 k.y. resolution) from St. Stephens Quarry, Alabama, USA, derived from foraminiferal Mg/Ca, d18O, and TEX86. We constrain sea-surface temperatures (SSTs) in the latest Eocene and early Oligocene and address the issue of climatic cooling during the EOT. Paleotemperatures derived from planktic foraminifera Mg/Ca and TEX86 are remarkably consistent and indicate late Eocene subtropical SSTs of 〉28 °C. There was substantial and accelerated cooling of SSTs (3–4 °C) through the latest Eocene “precursor” d18O shift (EOT-1), prior to Oligocene Isotope-1 (Oi-1). Our multispecies planktic foraminiferal d18O records diverge at the E/O boundary (33.7 Ma), signifying enhanced seasonality in the earliest Oligocene in the Gulf of Mexico.
    Print ISSN: 0091-7613
    Electronic ISSN: 1943-2682
    Topics: Geosciences
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