1,736,678 research outputs found
Foraminiferal study of ODP Hole 189-1171
No full textSequence boundary ages determined in shallow-water sediments obtained from ODP (Ocean Drilling Program) Leg 189 Site 1171 (South Tasman Rise) compare well with other stratigraphic records (New Jersey, United States, and northwestern Europe) and d18O increases from deep-sea records, indicating that significant (>10 m) eustatic changes occurred during the early to middle Eocene (51-42 Ma). Sequence boundaries were identified and dated using lithology, bio- and magnetostratigraphy, water-depth changes, CaCO3 content, and physical properties (e.g., photospectrometry). They are characterized by a sharp bioturbated surface, low CaCO3 content, and an abrupt increase in glauconite above the surface. Foraminiferal biofacies and planktonic/benthic foraminiferal ratios were used to estimate water-depth changes. Ages of six sequence boundaries (50.9, 49.2, 48.5-47.8, 47.1, 44.5, and 42.6 Ma) from Site 1171 correlate well to the timings of d18O increases and sequence boundaries identified from other Eocene studies. The synchronous nature of sequence boundary development from globally distal sites and d18O increases indicates a global control and that glacioeustasy was operating in this supposedly ice-free world. This is supported by previous modeling studies and atmospheric pCO2 estimates showing that the first time pCO2 levels decreased below a threshold that would support the development of an Antarctic ice sheet occurred at ca. 51 Ma. Estimates of sea-level amplitudes range from ~20 m for the early Eocene (51-49 Ma) and ~25 m to ~45 m for the middle Eocene (48-42 Ma) using constraints established for Oligocene d18O records
Magnesium and Strontium compositions of pore fluids and bulk carbonates from Ocean Drilling Project Site 189-1171
No full textThe Mg and Sr isotopic compositions (d26Mg and87Sr/86Sr) of pore fluids and bulk carbonates from Ocean Drilling Project Site 1171 is located on the South Tasman Rise (48°29.996000S and 149°06.690100E) at a present-day waterdepth of 2148.2 m on a southwesterly dipping slope
William II of Hauteville (1171–1189)
No full textWilliam II of Hauteville King of Sicily (1171–1189). William II of Hauteville was the third king of the Norman dynasty on the throne of Sicily. He ruled independently from 1171 (from 1166 to 1171 he was under the regency of his mother) to 1189. From an iconographic point of view, he is particularly interesting because he was the first king of Sicily who made use of monumental images of himself. In particular, we have five official (namely, commissioned directly by him or his entourage) representations of him: the royal bull, the royal seal, and three images from the Cathedral of Monreale (near Palermo): two mosaic panels and one carved capital
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Harm, Linda (FA 1171)
Full text linkFinding aid only for Folklife Archives Project 1171. Student paper titled “Snakelore” in which Linda Harm investigates commonly held beliefs and misconceptions relating to snakes and their behaviors. Harm collected stories from family members, friends, and classmates
(Table T1) Phosphorus and metal concentrations of ODP Site 189-1171
No full textA primary goal of Leg 189 was to evaluate Cenozoic changes in ocean circulation and the subsequent influence on climate variability (Exon, Kennett, Malone, et al., 2001, doi:10.2973/odp.proc.ir.189.2001; Exon et al., 2002, doi:10.1029/2002EO000176). Our approach is to use bulk sediment geochemical records to try to understand the influences of changing ocean circulation and climate on biogeochemical cycles and export production (e.g., Latimer and Filippelli, 2001, doi:10.1029/2000PA000586; 2002, doi:10.1016/S0031-0182(01)00493-X).
Site 1171 (48°S, 149°E) is located on the South Tasman Rise at a water depth of ~2150 m. Late Paleocene to late Eocene age sediments represent shallow-water silty claystones and claystones (Exon, Kennett, Malone et al., 2001, doi:10.2973/odp.proc.ir.189.2001). A 6-m section of glauconitic sandstone to siltstone is observed in the uppermost upper Eocene and is followed by a sharp lithologic change from shallow-water siliciclastics to pelagic carbonates (Exon, Kennett, Malone, et al., 2001, doi:10.2973/odp.proc.ir.189.2001). Sediments of Oligocene age to present are predominantly nannofossil ooze or chalk.
Sediment geochemistry allows us to identify changes in metal sources and terrigenous inputs using elemental data based on Fe, Al, and Ti concentrations and elemental ratios, such as Al/Ti and Fe/Ti. To assess export production, we use records of phosphorus (P) and barium (Ba) concentrations and P/metal and Ba/metal ratios, with elevated values being interpreted as higher export production
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