DSDP Hole

Kawahata, H., Kusakabe, M. and Kikuchi, Y. (1987) Strontium, oxygen, and hydrogen isotope geochemistry of hydrothermally altered and weatherted rocks in DSDP Hole 504B, Costa Rica Rift. Earth Planet. 

Kawahata, H. and Shikazono, N. (1988) Sulfur isotopes and total sulfur studies of basalts and greenstones from DSDP Hole 504B, Costa Rica Rift. Can. Mineral., 26, 555-566. 

The first modem publication of Li isotope data from sediments came from Chan et al. (1994a), who reported the isotopic compositions of unaltered turbidites from DSDP Hole 477 and All A, from the Gulf of California. These samples have been reanalyzed (LH Chan, written communication 2003), yielding lighter values. Similarly, Chan and Frey (2003) suggested a range for marine clastic sediments (5 Li = -1 to +5.6) based on new data and re-analysis of samples previously considered to be isotopicaUy heavy. 

Laveme C (1993) Occurrence of siderite and ankerite in young basalts from the Galapagos Spreading Center (DSDP Holes 506G and 507B). Chem Geol 106 27-46... 

Alt J. C., Honnorez J., Laverne C., and Emmermann R. (1986) Hydrothermal Alteration of a 1 km section through the upper oceanic crust DSDP hole 504B the mineralogy, chemistry and evolution of seawater-basalt interactions. J. Geophys. Res. 91, 10309-10335. 

New Jersey Margin DSDP Hole 603 4,796 ys. Spy, SSpy (Bonnell and Anderson, 1987 Dean and Arthur, 1987)... 

Holmes M. A. (1988) Evidence for continuous and discontinuous alteration in DSDP hole 418A basalts and its significance to natural gamma-ray log readings. In Proceedings of Ocean Drilling Project Scientific Results (eds. M. H. Salisbury and J. H. Scott, et al.), vol. 102, pp. 135-149. 

Alt, J. C., Muehlenbachs, K. Honnorez, J. 1986. An oxygen isotope profile through the upper kilometer of the oceanic crust, DSDP Hole 504B. Earth and Planetary Science Letters, 80, 217-229. 

Alt J C, Muehlenbaehs K, Hoimorez J (1986) An oxygen isotopic profile throngh the npper kilometer of the oceanic crust, DSDP hole 504B. Earth Planet Sci Letters 80 217-229 Anderson AT, Clayton RN, Mayeda TK (1971) Oxygen isotope thermometiy of mafic igneons rocks. 

Alt J, Satzman ES, Price D (1985) Anhydrite in hydrothermally altered basalts DSDP hole 504B. In Anderson RN, Hoimorez J, Baker K, et al. (eds) Initial Reports DSDP 83 283-288. U S Govt Printing Office, Washington, DC... 

Twenty samples of cherts from the Central Pacific were selected for analysis. Of those, 18 are in stratigraphic sequence from DSDP Hole 167 (Leg 17). Hole 167 was drilled atop the Magellan Rise in the Central Pacific. It penetrated about 1200 m of nanofossil chalk, limestones and cherts, Tithonian to Pleistocene in age. Starting with core 33, at a depth of 605 m below sea floor (mbsf), cherts were recovered in the sequence. The cherts occur either as part of the carbonate sequence or, very often as broken fragments in the core catcher (marked cc in Table 1). 

A rather systematic variation of B concentration and 8 B values is observed with depth for samples from DSDP Hole 167 (Fig. 4). B concentrations increase regularly from —70 ppm at 605 mbsf to a maximum of —100 ppm at 770 mbsf (sample 167-50-cc) and decrease then to reach —40-50 ppm at 1200 mbsf. The 8 B values also show a pattern of change with depth 8 B values increase from — 0%o at 605 mbsf to - -l.l%c at 770 mbsf and then decrease to negative values at greater depth. A similar profile is observed for values (Fig. 4) ... 

The effect of maturation on the stable carbon isotope compositions of the kerogen samples is plotted in Fig. 10b. The offset of about 3%o, due to the different source organic matter above versus below the sills, is evident. There is a progressive increase in with increasing alteration temperature and the enrichment in is about %c. An enrichment of about 2%c was reported for the in situ kerogen samples from DSDP Hole 368 (Simoneit et al, 1981) and other investigators have also reported that carbon isotopic alteration of... 

The effects of laboratory thermal alteration experiments (low water-rock ratio) on the organic matter of composited Cretaceous black shale samples from DSDP Hole 368 are evident in the following parameters (1) for the hydrocarbons—total yield, formation of PAH and thio-PAH compounds, and increase of Pr/Ph and (2) for kerogen—atomic H/C, HI, 6 C, and vitrinite reflectance (cf. Tables 1 and 2). 

Zimmerman H.B., Shackleton N.J., Backman J Kent D.V., Baldauf J.G., Kaltenback A.J. and Morton A.C. (1981) History of plio-pleistocene climate in the northeastern Atlantic, deep sea drilling project hole 552A. DSDP 81, 861-875. 

Ishikawa T. and Nakamura E. (1992) Boron-isotope geochemistry of the oceanic crust from DSDP/ODP Hole 504B. Geochim. Cosmochim. Acta 56, 1633—1639. 

Pedersen R. B. and Fumes H. (2001) Nd- and Pb-isotopic variations through the upper oceanic cmst in DSDP/ ODP Hole 504B, Costa Rica Rift. Earth Planet. Sci. Lett. 189, 221-235. 

Barret T. J. and Friedrichsen H. (1982) Strontium and oxygen isotopic composition of some basalts from Hole 504B, Costa Rica Rift, DSDP Legs 69 and 70. Earth Planet Sci. Lett. 60, 27-38. 

Mathez E. A. (1980) Sulfide relations in Hole 418A flows and sulfur contents of glasses. In Initial Reports DSDP (eds. T. Donnelly, J. Francheteau, W. Bryan, P. Robison, M. Flower, and M. Salisbury). US Government Printing Office, vol. 51-53, pp. 1069-1085. 

Although many of the in situ Cretaceous oceanic plateaus have been drilled by the Deep Sea Drilling (DSDP) and Ocean Drilling Programs (ODP), the insight that these drill holes can provide is relatively limited compared to the... 

Figure 4 Map to show the main accreted outcrops of the Caribbean-Colombian oceanic plateau along with the locations of DSDP/ODP drill holes which penetrated the thickened crust of the Caribbean plate.

The Ontong Java plateau (OJP) in the western Pacific (Figure 1) has been tectonically uplifted and exposed along its south eastern margin, at the Solomon Islands arc, mostly on the Islands of Maliata and Santa Isabel. In contrast to the CCOP, which has numerous exposed sections, these are currently the only known subaerial exposures of the OJP. The rest of our knowledge of the OJP comes from a series of drill holes DSDP Site 289 and OOP Sites 803 and 807 (Mahoney et al. 

On Maliata the stratigraphic thickness of the accreted plateau reaches 3-4 km, and the succession is dominated by pillowed and massive basaltic flows (Petterson et al., 1997 Babbs, 1997). Like the CCOP, dykes are volumetrically minor. The DSDP/ODP drill holes have penetrated into the plateau to a depth of 216 m (Site 1185B Mahoney et at, 2001). The sampled sections consist predominantly of pillowed and massive basalts with occasional thin interlava sediments (Neal et al., 1997 Mahoney et al., 2001)... 

Lalou, C., Brichet, E., Jehanno, C. and Perez-Leclaire, H., 1983. Hydrothermal manganese oxide deposits from Galapagos mounds, DSDP Leg 70, hole 509B and Alvin dives 729 and 721. Earth and Planetary Science Letters, 63 63-75. 

Abstract—Twenty samples of cherts from the Central Pacific (18 of them from DSDP, Legl7, Hole 167) were analyzed for B content and by ion-probe. In aU samples S 0, Sr/ Sr and Ge have been previously measured. S B of DSDP cherts varies between — 9.3 and + 8%o, indicating a bulk fractionation of 32-45%o with respect to present day seawater B (39.5%c), the highest fractionation of any marine phase. This fractionation is similar to the previously observed values in opal-A radiolarians (having S B of - -2 to - -4.5%o. Earth Planet. Sci. Lett. 117, 1993, 567-580). Siliceous sediments are a significant sink of boron in the ocean, an even more significant sink of °B. Assuming no secular variation in our... 

Boron concentration in the analyzed DSDP cherts varies between 44 and 104 ppm and value between -9.3 1.6%o and +7.7 1.2%o (Table 1, Fig. 3). The range of values reported here overlaps and includes those observed in opal-A radiolarians and diatoms (+ 2.2 to + 4.5%c, IsHiKAWA and Nakamura, 1993). Some of the DSDP cherts analyzed by us have very low 8 B values lending further support to the general claim of Lemarchand et al (2002) that boron sinks from the ocean are B enriched. The two chert samples from Holes 169 and 195 have 8 B values within the range defined by cherts from Hole 167 but tend to have low B concentrations and low values. 

Fig. 5. Variation of with B concentration in cherts of Hole 167. The present DSDP cherts scatter around a correlation line previously suggested by Hein et al. (1981) for cherts from Leg DSDP 62 in the mid-Pacific. As a first order observation, B is lost by cherts during diagenesis with increasing temperature.

Table 1. Summary of DSDP/ODP holes for which data have been measured...

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