Not logged in
PANGAEA.
Data Publisher for Earth & Environmental Science

Bougault, Henri; Joron, Jean Louis; Treuil, M; Maury, R C (1985): Geochemistry in the mid Atlantic Ocean ridge basalts [dataset publication series]. PANGAEA, https://doi.org/10.1594/PANGAEA.806082, Supplement to: Bougault, H et al. (1985): Local versus regional mantle heterogeneities: Evidence from hygromagmaphile elements. In: Bougault, H; Cande, SC; et al. (eds.), Initial Reports of the Deep Sea Drilling Project, Washington (U.S. Govt. Printing Office), 82, 459-482, https://doi.org/10.2973/dsdp.proc.82.123.1985

Always quote citation above when using data! You can download the citation in several formats below.

RIS CitationBibTeX CitationShow MapGoogle Earth

Abstract:
The main objective of Leg 82 of the Glomar Challenger was to document mantle heterogeneity in the vicinity of, and away from, a so-called hot spot: the Azores Triple Junction. One of the geochemical tools that permits, at least in part, the recognition of mantle heterogeneities uses hygromagmaphile elements, those elements that have an affinity for the liquid. This tool is presented in terms of an extended Coryell-Masuda plot, which incorporates within the rare earth elements the hygromagmaphile transition elements Th, Ta, Zr, Hf, Ti, Y, and V. The extended Coryell-Masuda plot is used to summarize our knowledge of mantle heterogeneity along the ridge axis at zero-age. It is also used by choosing those hygromagmaphile elements that can be analyzed on board by X-ray fluorescence spectrometry to give preliminary information on the enriched or depleted character of recovered samples. Shore-based results, which include analyses of most of the hygromagmaphile elements measured either by X-ray spectrometry or neutron activation analysis, confirm the shipboard data.
From the point of view of comparative geochemistry, the variety of basalts recovered during Leg 82 provides a good opportunity to test and verify the classification of the hygromagmaphile elements. Analyses from Leg 82 provide new data about the relationship between extended rare earth patterns (enriched or depleted) that can be estimated either by La/Sm ratio or Nb/Zr (or Ta/Hf) ratios: samples from Hole 556 are depleted (low Nb/Zr ratio) but have a high 206Pb/ 204Pb (19.5) ratio; in Hole 558 a moderately enriched basalt unit with a La/Sm (= Nb/Zr) ratio (chondrite normalized) of 2 has a high 206Pb/204Pb (20) ratio. One of the most interesting results of Leg 82 lies in the crossing patterns of extended Coryell-Masuda plots for basalts from the same hole. This result enhances the notion of local mantle heterogeneity versus regional mantle heterogeneity and is confirmed by isotope data; it also favors a model of short-lived, discrete magma chambers. The data tend to confirm the Hayes Fracture Zone as a southern limit for the influence of Azores-type mantle. Nevertheless, north of the Hayes Fracture Zone, the influence of a plumelike mantle source is not simple and probably requires an explanation more complex than a contribution from a single fixed hot spot.
Project(s):
Deep Sea Drilling Project (DSDP)
Coverage:
Median Latitude: 34.423313 * Median Longitude: -36.961122 * South-bound Latitude: 10.616667 * West-bound Longitude: -46.250000 * North-bound Latitude: 39.783333 * East-bound Longitude: -20.900000
Date/Time Start: 1977-10-01T00:00:00 * Date/Time End: 1981-10-21T00:00:00
License:
Creative Commons Attribution 3.0 Unported (CC-BY-3.0)
Size:
7 datasets

Download Data

Download ZIP file containing all datasets as tab-delimited text — use the following character encoding:

Datasets listed in this publication series

  1. Bougault, H; Joron, JL; Treuil, M et al. (1985): (Table 5) Geochemistry of plagioclases at DSDP Holes 82-557, 82-561 and 82-562. https://doi.org/10.1594/PANGAEA.806076
  2. Bougault, H; Joron, JL; Treuil, M et al. (1985): (Table 4) Geochemistry of groundmass titanomagnetites at DSDP Holes 82-557, 82-561 and 82-562. https://doi.org/10.1594/PANGAEA.806050
  3. Bougault, H; Joron, JL; Treuil, M et al. (1985): (Table 3) Geochemistry of clinopyroxenes at DSDP Holes 82-557 and 82-561. https://doi.org/10.1594/PANGAEA.806049
  4. Bougault, H; Joron, JL; Treuil, M et al. (1985): (Appendix C) Geochemistry at DSDP Holes 82-558 and 77-540. https://doi.org/10.1594/PANGAEA.806080
  5. Bougault, H; Joron, JL; Treuil, M et al. (1985): (Table 2) Geochemistry of olivines at DSDP Hole 82-561. https://doi.org/10.1594/PANGAEA.806048
  6. Bougault, H; Joron, JL; Treuil, M et al. (1985): (Appendix B) Ratios of hygromagmaphile element concentrations normalized to chondrites between the latitudes 40°N to 10°N. https://doi.org/10.1594/PANGAEA.806078
  7. Bougault, H; Joron, JL; Treuil, M et al. (1985): (Appendix A) Trace elements at MAPCO cruise Legs CH97 and CH98. https://doi.org/10.1594/PANGAEA.806077