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Table T1. Leg 200 operations summary.
Table T2. Summary of holes drilled in normal crust on the Pacific plate with an age <100 Ma and penetration into basement >10 m.
Table T3. Coring summary for Site 1224.
Table T4. Coring summary, Site 1223.
Figure F1. Locations of Site 1224 and the Hawaii-2 Observatory (H2O) junction box (large star), repeater locations along the Hawaii-2 cable (crosses), major fracture zones (FZ), and previous drill sites (circles) from DSDP Legs 5 (Sites 38, 39, 40, and 41) and 18 (Site 172). Superimposed on the map is the satellite-derived bathymetry.
Figure F2. This artist's conception of the Hawaii-2 Observatory (H2O) summarizes some of the important components of the installation (© copyright Jayne Doucette, Woods Hole Oceanographic Institution [WHOI]. Reproduced with permission of WHOI).
Figure F3. The location of the Hawaii-2 Observatory (H2O) junction box is shown on the Hydrosweep bathymetry acquired during the site survey in August 1997 (Stephen et al., 1997). The locations of the repeaters (AT&T waypoints) on the cable are also shown (filled triangles).
Figure F4. A 3.5-kHz echo sounder record showing that the seafloor dips smoothly ~6 m from the H2O junction box to Site 1224 (proposed Site H2O-5). One subbottom horizon at ~9 m is fairly uniform throughout the area. Based on drilling results, this is a midsediment reflector. A second reflector at ~30 m below the junction box may be associated with basaltic basement, although it appears only occasionally in the record. PDR = precision depth recorder.
Figure F5. Vertical component spectra from the seafloor, buried, and borehole installations at the OSN-1 (Ocean Seismic Network) are compared with the spectra from the buried installation at the H2O and from the KIP GSN station on Oahu. The H2O has extremely low noise levels above 5 Hz and near the microseism peak from 0.1 to 0.3 Hz. The H2O has high noise levels below 50 mHz. Otherwise, the H2O levels are comparable to the OSN borehole and KIP levels. The sediment resonances at the H2O near 1.1 and 2.3 Hz are very prominent. Power spectral density is given in decibels relative to 1 (m/s2)2/Hz.
Figure F6. Horizontal component spectra from the seafloor, buried, and borehole installations at the OSN-1 (Ocean Seismic Network) are compared with the spectra from the buried installation at the H2O and from the KIP GSN station on Oahu. The sediment resonance peaks in the band 0.3 to 8 Hz are up to 35 dB louder than background levels and far exceed the microseism peak at 0.1 to 0.3 Hz. That the resonance peaks are considerably higher for horizontal components than for vertical components is consistent with the notion that these are related to shear wave resonances (or Scholte modes). Power spectral density is given in decibels relative to 1 (m/s2)2/Hz.
Figure F7. All drilling at the Hawaii-2 Observatory (H2O) took place at Site 1224 (proposed Site H2O-5), which is 1.48 km northeast of the junction box at the H2O. Alternate drilling sites (H2O-1 through H2O-4) that were discussed in the Leg 200 Prospectus are also shown (circles with crosses). Circles are drawn at 1-, 2-, and 3-km radius from the junction box. Also shown are the location of the single-channel seismic lines acquired during the site survey cruise in 1997 (dashed lines) and the track line taken by the JOIDES Resolution on 26 December 2001 (solid line). Echo sounder recordings were made along this line.
Figure F8. Coccoliths (spherical) and discoasters (star shaped) from Section 200-1224E-2R-7.
Figure F9. Lithologic summary of basalts cored at Site 1224. Basalt recovered in cores that penetrated basement are placed below the average depth estimated for the basement contact, which is 28 mbsf. Otherwise, the top of the recovered core is assumed by convention to start at the top of the cored interval. Locations of thin section samples are shown by red dots. Sediments are shown down to the presumed basement contact at 28 mbsf, but, as with the basalts, the depth of recovery is only known to lie somewhere within the cored interval and somewhere above the basalt.
Figure F10. Flow-top hyaloclastite from lithologic Unit 2 cemented by calcite (interval 200-1224F-6R-1 [Piece 6, 29–33 cm]). Fresh glass is very dark gray; altered glass is gray; palagonitized glass is orange; and calcite is white and light gray.
Figure F11. Chemical compositions vs. depth for basalts from Hole 1224D. A. TiO2 vs. depth. B. Zr vs. depth. The vertical lines suggest the possible breakdown of the hole into two chemical types based on TiO2 and three types based on Zr concentrations.
Figure F12. Sampling point and identification of the main secondary minerals in the basement section at Site 1224. Colored symbols show typical minerals. Green = clay, blue = carbonate, gray = quartz, and yellow = zeolite.
Figure F13. Microphotograph showing bacterial cells from an upper sediment layer from a depth of 1.45 mbsf (interval 200-1224C-1H-4, 145–150 cm). A. After staining with the DNA-binding fluorochrome SYBR Green I. B. Hybridization with the bacteria-specific, CY3-labeled probe EUB338. Note the numerous bacteria responding to the specific hybridization, indicating the high amount of metabolically active bacteria within the sediment.
Figure F14. Compressional wave velocities vs. depth in Holes 1224D, 1224E, and 1224F. Seven depth zones are introduced, as seen on the far right. Compressional wave velocities in the three holes have similar depth dependence between 27 and 53 mbsf. Zones 1 and 2 correspond to logging Unit I (Fig. F15), Zone 3 corresponds to logging Unit II, Zone 4 corresponds to logging Unit III, Zones 5 and 6 correspond to logging Unit IV, and Zone 7 corresponds to logging Unit V.
Figure F15. Composite log of the temperature, spontaneous potential (SP), and electrical resistivity logs recorded in Hole 1224F during Leg 200. Track 1: temperature. Track 2: SP. Track 3: deep induction resistivity (ILD). Track 4: spherically focused resistivity log (SFLU).
Figure F16. Logging data in Hole 1224F: caliper, resistivity, neutron porosity (NPHI), and gamma ray bulk density (RHOB). The arrows indicate the boundaries of the five logging units shown in Figure F15 and discussed in the text.
Figure F17. Tracking RMS (root-mean square) levels in one-octave bands is a convenient way to observe time-dependent effects in the broadband seismic data from the Hawaii-2 Observatory. The spikes around 5 and 20 s in this figure correspond to T-phases from earthquake events. The intense activity between 10 and 15 hr can be associated with the drawworks.
Figure F18. Location of Site 1223 and the Nuuanu Landslides. Line 12 shows the seismic reflection profile collected during the 1988 Thomas Washington cruise (Rees et al., 1993). The bathymetry shows that Site 1223 is near a seamount.
Figure F19. Lithologic units of Site 1223.
Figure F20. Schematic drawing of a landslide and the resulting directed blast eruption (from Moore and Albee, 1981).
Figure F21. Major-oxide discriminant diagrams. A, C. Al2O3 vs. Fe2O3. B, D. SiO2 vs. Al2O3. Symbols distinguish vitric tuffs (red left-pointing triangles) and siltstones (gray triangles). Arrows in A and B indicate the effects of subtraction of 13% olivine = Fo85 from a representative tuff composition. Additional symbols in A and B are large open triangles = basaltic glasses from Kilauea and Puna Ridge (Clague et al., 1995); half-filled squares = Honolulu Volcanic Series (Jackson and Wright, 1970; Clague and Frey, 1982); downward-pointing triangles = North Arch Volcanic Series (Dixon et al., 1997); blue diamonds = Hana Volcanic Series, Haleakala Volcano, Maui (Chen et al., 1991). Additional symbols in C and D are dark green squares = high-MgO basalts from Koolau Volcano, Oahu (Frey et al., 1994); light green right-pointing triangles = enriched mid-ocean-ridge basalt (E-MORB) (data compilation of J. Natland, from several literature sources).
Figure F22. Ternary diagrams showing effects of addition of detrital and authigenic clays to basaltic volcaniclastic material. Inset diagrams show placement of enlarged portions of ternary diagrams on which data are plotted. A. CaO-Al2O3-K2O (CAK) diagram. B. Total iron as MgO-Al2O3-Fe2O3(T) (MAF) diagram. Symbols distinguish vitric tuffs (red left-pointing triangles) and siltstones (gray triangles). Fields 1 and 2 distinguish vitric tuff samples having, respectively, higher proportions of detrital clay, inferred from their proportionate increase in Al2O3. Small triangles = glasses from Kilauea and Puna Ridge (Clague et al., 1995); small dots = normal mid-ocean-ridge basalt (N-MORB) glasses from the Pacific-Antarctic East Pacific Rise; large purple dots = N-MORB glass from DSDP Site 501 and three portions of its palagonitized rim (Noack et al., 1983). Fields for kaolinite (K), illite (I), and continental montmorillonite (M) are from Grim (1964). Average pelagic clay (PC) is from Cronan and Toombs (1969). The saponite nontronite (sap and non) fields (inset diagrams only) are for vein and replacement clays in basalts of DSDP Hole 504B (Honnorez et al., 1983).
Figure F23. Comparison of analyses of samples from Hole 1223A with Kilauea-Puna Ridge and Koolau tholeiites plus enriched mid-ocean-ridge basalt (E-MORB) and MORB. A. MgO vs. SiO2. B. MgO vs. Ba. C. MgO vs. Zr. The general effect of subtraction of olivine with 45% MgO is indicated by the arrow. Symbols distinguish vitric tuffs (red left-pointing triangles) and siltstones (gray triangles). Large open triangles = basaltic glasses from Kilauea and Puna Ridge (Clague et al., 1995); dark green squares = high-MgO basalts from Koolau Volcano, Oahu (Frey et al., 1994); light green right-pointing triangles = E-MORB (data compilation of J. Natland, from several literature sources); small dots = normal mid-ocean-ridge basalt (N-MORB) glasses from the Pacific-Antarctic East Pacific Rise.
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