CONCLUSIONS

Two subseafloor reflecting interfaces in the sediments were identified and drilled. There were four reflection sequences from the basalt basement. Based on the changes in acoustic impedance indicated by the reflections, the following stratigraphic sequence is suggested:

  1. The 11-ms interval between the seafloor and the first subsurface reflection corresponds to unconsolidated yellow to brown clay of which 9 m was recovered. The sound velocity of this material is near that of water.
  2. The 25-ms interval between the first and second subseafloor reflectors corresponds to a somewhat more consolidated sedimentary sequence ~19 m thick. Little core was retrieved from this interval.
  3. Basaltic basement is an irregular surface at a depth of ~28 meters below seafloor. Taken together, the 32-, 36-, and 39-ms reflections suggest basement relief of up to 7 m within 40 m of Site 1224.

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