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Science 25 August 1967:
Vol. 157. no. 3791, pp. 923 - 924
DOI: 10.1126/science.157.3791.923
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Articles

Sea Floor Spreading, Topography, and the Second Layer

H. W. Menard 1

1 Institute of Marine Resources, Scripps Institution of Oceanography, La Jolla, California 92038

Local sea floor topography and also the thickness of the second layer of the oceanic rise-ridge system appear related to the spreading rate in the region. Slow spreading, away from the ridge center at 1 to 2 centimeters per year, is associated with a thick second layer, a central rift, and adjacent rift mountains. Fast spreading, 3 to 4.5 centimeters per year, is associated with a thin second layer and subdued topography lacking any central rift. The volume of lava discharged in this layer per unit time and per unit length along the crest of the whole active system is relatively constant regardless of the spreading rate. Total second layer discharge of the system has been about 5 to 6 cubic kilometers per year during the last several million years.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Volcanic Production Rates: Comparison of Oceanic Ridges, Islands, and the Columbia Plateau Basalts.
A. K. Baksi, A. K. Baksi, and N. D. Watkins (1973)
Science 180, 493-496
   Abstract »    PDF »
Fissure Basalts and Ocean-Floor Spreading on the East Pacific Rise.
R. P. Von Herzen, R. P. Von Herzen, and E. Bonatti (1969)
Science 166, 1181-1183
   PDF »
Block Faulting on the Gorda Rise.
T. M. Atwater, T. M. Atwater, and J. D. Mudie (1968)
Science 159, 729-731
   Abstract »    PDF »


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