Distribution of quaternary siliceous sponge spicules in sediments of ODP Leg 180 sites

Siliceous sponge spicules were found in Quaternary sediments recovered during drilling of Leg 180. The assemblage consists mainly of monaxon forms. Relative abundances of the various types are tabulated.

Geochemistry and mineralogy of interstitial waters and clays in sediments of ODP Leg 180 sites

Oxygen and strontium isotopes and Rb and Ba were determined in interstitial water (IW) collected from Sites 1109, 1115, and 1118 drilled on the Woodlark Rise during Ocean Drilling Program Leg 180. The trace element and mineralogical composition of the clay fraction of sediments isolated from the squeeze cakes corresponding to IW samples from Site 1109 was also determined.

(Table T3) Vitrinite reflection of samples obtained from ODP Leg 180 sites

Seventy-one samples from Ocean Drilling Program Leg 180 sites were analyzed for vitrinite reflectance and organic type. The objective was to define maximum paleotemperatures across the western Woodlark Basin as a function of depth. The organic matter is of early Pliocene to Holocene age and was recovered from drilled depths of 4.5 to 851.3 meters below seafloor. Organic matter is generally restricted to woody fragments within the sediment, although in a number of fine-grained samples, organic matter is dispersed throughout the sample. Virtually all samples contain vitrinite, part of which may be derived from drifted logs. One sample was found to be barren of organic matter, and two contain only fusinite and semifusinite. Variation of vitrinite reflectance is not systematic with either depth or location, and it appears that formation temperatures have been insufficient to cause an increase in vitrinite reflectance levels. Textural variations within the vitrinite show better correlation with depth. Samples of hypautochthonous peats represent either a terrestrial phase of sedimentation or large peat intraclasts within the section, possibly produced by forest fires in the source areas of the organic matter. The vitrinite and peat-derived samples appear to come from eucalyptus forest settings away from the coastline. Liptinite is not abundant in most of the samples (excluding suberinite associated with woody tissues). Marine liptinite is rare to absent, although many of the samples contain abundant foraminiferal tests. Pyrite is abundant in many of the wood fragments, and some pyritization of woody tissues has taken place.

(Table T2) Rock magnetic parameters of ODP Leg 180 sites

Rock magnetic measurements were performed on sediments above 20 meters below seafloor (mbsf) (general) and above 2.5 mbsf (detailed) at Sites 1109, 1110, and 1115 (Ocean Drilling Program Leg 180) in the western Woodlark Basin. Rock magnetic parameters imply the presence of magnetite as a principal magnetic mineral in the sediments. The hysteresis ratios lay in the pseudo-single domain field and generally showed the trend close to that for the mixture of single domain and multidomain magnetite The sediments in the oxidized zones at the top at Sites 1109 and 1115 provided a different trend in the logarithmic plot of the hysteresis ratios, and the oxidized samples were characterized by higher coercivity.