Site 920

Abstract

Time on hole: 1 day, 11 hr, 03 min Position: 23°20.310'N, 45°1.038'W Bottom felt (drill-pipe measurement from rig floor, m): 3339.00 Distance between rig floor and sea level (m): 10.50 Water depth (drill-pipe measurement from sea level, m): 3328.50 Total depth (from rig floor, m): 3353.00 Penetration (m): 14.00 Number of cores (including cores with no recovery): 1 Total length of cored section (m): 28.00 Total core recovered (m): 1.68 Core recovery (%): 6 Oldest sediment cored: Unknown Hard rock: Depth (mbsf): 14.00 Nature: Polygenic gravel Comments: Predominantly serpentinized peridotite HOLE 920B Time on hole: 4 days, 17 hr, 15 min Position: 23°20.310'N, 45°1.038'W Bottom felt (drill-pipe measurement from rig floor, m): 3339.00 Distance between rig floor and sea level (m): 11.10 Water depth (drill-pipe measurement from sea level, m): 3327.90 Total depth (from rig floor, m): 3465.40 Penetration (m): 126.40 Number of cores (including cores with no recovery): 13 Total length of cored section (m): 126.40 Total core recovered (m): 47.78 Core recovery (%): 39.7 Oldest sediment cored: None Hard rock: Depth (mbsf): 126.40 Nature: Serpentinized harzburgite, diabase oxide gabbro, gneissic amphibolite Measured velocity (km/s): 3.65-5.76 1 Cannat, M., Karson, J.A., Miller, D.J., et al, 1995. Proc. ODP, Init. Repts., 153: College Station, TX (Ocean Drilling Program). Shipboard Scientific Party is given in the list of participants preceding the contents. Time on hole: 3 days, 18 hr, 10 min Position: 23°20.304'N, 45°1.032'W Bottom felt (drill-pipe measurement from rig floor, m): 3343.0 Distance between rig floor and sea level (m): 10.80 Water depth (drill-pipe measurement from sea level, m): 3332.2 Total depth (from rig floor, m): 3359 Penetration (m): 16.0 Number of cores (including cores having no recovery): 0 Total length of cored section (m): 0.00 Total core recovered (m): 0.00 Core recovery (%): 0 Oldest sediment cored: None Hard rock: None Comments: Hard-rock guide base (HRGB) shifted too much to continue drilling Time on hole: 6 days, 12 hr, 10 min Position: 23°20.322'N, 45°1.044'W Bottom felt (drill-pipe measurement from rig floor, m): 3338.00 Distance between rig floor and sea level (m): 10.50 Water depth (drill-pipe measurement from sea level, m): 3327.50 Total depth (from rig floor, m): 3538.80 Penetration (m): 200.80 Number of cores (including cores with no recovery): 22 Total length of cored section (m): 200.80 Total core recovered (m): 95.08 Core recovery (%): 47 Oldest sediment cored: None Hard rock: Depth (mbsf): 200.80 Nature: Serpentinized harzburgite, diabase, metagabbro, oxide gabbro Measured velocity (km/s): 3.90-5.21