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BC1-846
No full text2 signers describe fantasy creatures, elicited by images in BC1-846.pdfSivia, Per
Revised late Pliocene composite section for ODP Site 138-846
No full textContents include data sets relevant to constructing a revised late Pliocene composite section by tuning color reflectance and gamma ray porosity evaluator data a high resolution downhole log, newly generated stable isotope and alkenone data from ODP Site 138-846, and newly generated stable isotope and alkenone data from ODP Site 138-850 that demonstrate the reliability of the new Site 138-846 composite section in the time interval around the M2 glaciation
[MKT 846 Train Locomotive, Negative]
No full textNegative of Missouri-Kansas-Texas Railway's 846 train locomotive. The dark, shadowed, round locomotive is covered in pipes and short smokestacks, a circular light at the front of it to the left. Small signs surround the light reading "846." A square cab with a rounded roof sits behind the locomotive to the right with white text along it reading "846." A rectangular cab is attached to the cab to the right. Several railroads, mostly empty, sits in the foreground. Dark utility poles sit along the railroads, peeking above the train. A white building is visible in the background to the left
Inscriptions 846 à 850
No full textInscriptions 846 à 850. In: Revue épigraphique du Midi de la France, tome 3, N°60, 1891. pp. 74-76
(Table 1) Geochemistry, accumulation rates and sea surface temperature estimation of ODP Site 138-846
No full textWe analyzed the unsaturation ratio (Uk37) of long-chain ketones - a molecular sea-surface temperature (SST) indicator û concentrations of carbonate and organic carbon in sediments from Site 846 in the eastern equatorial Pacific Ocean. Based on an isotopic age model for the composite depth section of 0-46 m below seafloor and on estimates of sediment density, accumulation rates of these biogenic compounds were calculated. Our combined temperature and biogenic flux record traces conditions at the origin of the South Equatorial Current over the last 1.3 m.y.
SSTs have fluctuated considerably over the interval studied. A long trend of gradual decrease from 24°C at 1.3 Ma ends between 500 and 400 Ka, when lowest values of 19°C were reached. Since this time, the temperature data indicate a warming trend to the Holocene modulated by high-amplitude variation (19° to 27°C). The inversion of the trend between 400 and 500 Ka coincides with maximal accumulation rates of carbonate, which since then have decreased. In contrast, organic carbon accumulation since then has increased in variability and in absolute values.
On shorter time scales, the records show a strong link to the global climatic background. Since 1.3 Ma, carbonate (0.2-3 g/cm**2/k.y.) and organic carbon accumulation rates (2-30 mg/cm**2/k.y.) were consistently high (more than twice their modern values and those of interglacials) during glacial maxima in the benthic isotope record, when temperatures were low.
However, cross-spectral analyses with the d18O record suggest that variation in organic carbon flux is not linked directly to variations in SST. Temperature maxima in our record led interglacial events by 7 k.y. in the 100-k.y. eccentricity cycle and by 5 k.y. in the 41-k.y. obliquity cycle. In contrast, maxima in organic carbon accumulation lag behind glacial maxima and low temperatures by 14 k.y. in the eccentricity cycle. On glacial/interglacial time scales, a prominent influence on SST - but not on organic carbon burial - at Site 846 appears to be the advection of cold water into the South Equatorial Current
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
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