Background and objectives 2 Operations 8 Lithostratigraphy 18 Biostratigraphy and micropaleontology 26 Paleomagnetism 39 Petrophysics 50 Geochemistry 56 Stratigraphic correlation 58 References

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In this report the geothermal measurements made with temperature probes on the JOIDES Resolution during legs 101-180 are reanalyzed in a standard systematic manner. Sediment temperatures were measured on 53 of the first 80 Ocean Drilling Project Legs. 205 of the 475 sites have reliable data. For 22% of sites with reliable values, however, heat flow data were not reported in the Initial Results volumes. A total of 993 reliable temperature measurements yields an average of 4.8 measurements per site. Most temperature measurements were between 20 to 250 mbsf, and the deepest depth in this study is 550 mbsf. Available thermal conductivity data for these 205 sites were corrected for in-situ conditions. Heat flow values, calculated using the Bullard method, range from 5 mW m-2 to 13 W m-2. Temperature, thermal conductivity, and heat flow data presented in this report are available from the included CD.

Deep-sea sedimentary deposits are important archives of the geological past which preserve the records of past environmental changes in Earth’s ocean. The detailed analysis of deep-sea sedimentary archives, in particular of contourite drifts, can help elucidate past changes in ocean circulation and the stratigraphic evolution of continental margins. However, the bathymetric profile of an oceanic basin can shape and modify the architecture of contourite drifts via the interaction between down-slope and along-slope processes. The identification of local bathymetric influence on depositional architectures is therefore important to help decipher local vs. regional influences on deep-sea sedimentary signatures. Seismic data from Mentelle Basin in the Southeast Indian Ocean integrated with deep-sea core data reveal a calcareous-siliciclastic mixed contourite-turbidite system developed during the late Cenozoic, starting in the middle Miocene. Current winnowing led to the formation of regional hiatuses, ferromanganese crusts and siliciclastic lag deposits. The main locus of sediment deposition occurred on the shallower parts of the basin while sediment preservation remained low in the deeper areas. Seismic analysis shows that inherited topography influenced the architecture of contourite deposits within the basin, with elongate-mounded and sheeted drifts forming preferentially at shallower depths on the continental slope and the Naturaliste Plateau, while channel incision occurred in the deepest parts of the basin. These results suggest that intensification of current transport occurred preferentially within the deeper and spatially constrained parts of the basin, while current deflection around the slope and plateau enhanced drift deposition and preservation at shallower depths. Therefore, basin topography at the time of deposition controlled the distribution of deep-sea deposits and drift morphologies within the mixed contourite-turbidite system in the Mentelle Basin.