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

Kastner, Miriam (1982): Descriptions, isotopes and minerals of sediments at DSDP Leg 64 Holes [dataset publication series]. PANGAEA, https://doi.org/10.1594/PANGAEA.819089, Supplement to: Kastner, M (1982): Evidence for two distinct hydrothermal systems in the Guaymas Basin. In: Curray, JR; Moore, DG; et al. (eds.), Initial Reports of the Deep Sea Drilling Project (U.S. Govt. Printing Office), 64, 1143-1157, https://doi.org/10.2973/dsdp.proc.64.154.1982

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

Published: 1982 (exact date unknown) • DOI registered: 2013-10-10

RIS CitationBibTeX Citation ShareShow MapGoogle Earth

Abstract:
Mineralogical and oxygen isotopic analyses of samples from Deep Sea Drilling Project Sites 477, 481, and 477 in the Guaymas Basin indicate the existence of two distinct hydrothermal systems. In the first, at Sites 481 and 478, hot dolerite sills intruded into highly porous hemipelagic siliceous mudstones that were moderately rich in organic matter, thermally altered the adjacent sediments, and expelled hydrothermal pore fluids. The second, at Site 477 and active at present, is most probably caused by a recent igneous intrusion forming a magma chamber at shallow depth.
In the first hydrothermal system, the main thermal reactions above and below the sills are dissolution of opal-A and formation of quartz, either directly or through opal-CT; formation of smectite; formation of analcime only above the sills; dissolution and recrystallization of calcite and occasional formation of dolomite or protodolomite. The d18O values of the hydrothermally altered sediments range from 9.9 to 12.2 per mil (SMOW). The d18O values of recrystallized calcites above the first sill complex, Site 481, indicate temperatures of 140° to 170°C. No fluid recharge is required in this system. The thickness of the sill complexes and the sequence and depth of intrusion into the sediment column determine the thickness of the alteration zones, which ranges from 2 or 3 to approximately 50 meters. Generally, the hydrothermally altered zone is thicker above than below the sill.
In the second type, the sediments are extensively recrystallized. The characteristic greenschist-facies mineral assemblage of quartz-albite-chlorite-epidote predominates. Considerable amounts of pyrite, pyrrhotite, and sphene are also present. The lowest d18O value of the greenschist facies rocks is 6.6 per mil, and the highest d18O value of the associated pore fluids is +1.38 per mil (SMOW). The paragenesis and the oxygen isotopes of individual phases indicate alteration temperatures of 300 ± 50°C. On the basis of the oxygen isotopes of the solids and associated fluids, it is concluded that recharge of fluids is required. The water/rock ratio in wt.% is moderate, approximately 2/1 to 3/1 - higher than the calculated water/rock ratio of the hydrothermal system at the East Pacific Rise, 21 °N.
Project(s):
Deep Sea Drilling Project (DSDP)
Coverage:
Median Latitude: 27.144305 * Median Longitude: -111.472532 * South-bound Latitude: 27.030000 * West-bound Longitude: -111.507700 * North-bound Latitude: 27.253000 * East-bound Longitude: -111.398800
Date/Time Start: 1978-12-18T00:00:00 * Date/Time End: 1979-01-03T00:00:00
Event(s):
64-477 * Latitude: 27.030800 * Longitude: -111.400300 * Date/Time: 1978-12-18T00:00:00 * Elevation: -2003.0 m * Penetration: 191 m * Recovery: 50.6 m * Location: North Pacific/Gulf of California/BASIN * Campaign: Leg64 * Basis: Glomar Challenger * Method/Device: Drilling/drill rig (DRILL) * Comment: 21 cores; 172 m cored; 19 m drilled; 29.4 % recovery
64-477A * Latitude: 27.030000 * Longitude: -111.398800 * Date/Time: 1978-12-18T00:00:00 * Elevation: -2003.0 m * Penetration: 267 m * Recovery: 16 m * Location: North Pacific/Gulf of California/BASIN * Campaign: Leg64 * Basis: Glomar Challenger * Method/Device: Drilling/drill rig (DRILL) * Comment: 11 cores; 111 m cored; 9.5 m drilled; 14.4 % recovery
64-478 * Latitude: 27.096800 * Longitude: -111.507500 * Date/Time: 1978-12-24T00:00:00 * Elevation: -1889.0 m * Penetration: 464 m * Recovery: 297.6 m * Location: North Pacific/Gulf of California/CHANNEL * Campaign: Leg64 * Basis: Glomar Challenger * Method/Device: Drilling/drill rig (DRILL) * Comment: 49 cores; 427 m cored; 24 m drilled; 69.7 % recovery
License:
Creative Commons Attribution 3.0 Unported (CC-BY-3.0)
Size:
9 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. Kastner, M (1982): (Table 1) Mineral zones in sediments at DSDP Hole 64-477. https://doi.org/10.1594/PANGAEA.819076
  2. Kastner, M (1982): (Appendix A) Minerals at DSDP Site 64-477. https://doi.org/10.1594/PANGAEA.819086
  3. Kastner, M (1982): (Table 3) Mineral zones in sediments at DSDP Hole 64-478. https://doi.org/10.1594/PANGAEA.819081
  4. Kastner, M (1982): (Appendix C) Minerals at DSDP Hole 64-478. https://doi.org/10.1594/PANGAEA.819088
  5. Kastner, M (1982): (Table 2) Mineral zones in sediments at DSDP Hole 64-481. https://doi.org/10.1594/PANGAEA.819079
  6. Kastner, M (1982): (Appendix B) Minerals at DSDP Site 64-481. https://doi.org/10.1594/PANGAEA.819087
  7. Kastner, M (1982): (Table 7) Isotopic composition of recrystallized calcite at contact with sill at DSDP Hole 64-481A. https://doi.org/10.1594/PANGAEA.819085
  8. Kastner, M (1982): (Table 6) δ¹⁸O of pore fluids at DSP Leg 64 Holes. https://doi.org/10.1594/PANGAEA.819084
  9. Kastner, M (1982): (Table 4) δ¹⁸O of bulk sediments at DSP Leg 64 Holes. https://doi.org/10.1594/PANGAEA.819083