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The Leeuwin Current is an anomalous eastern boundary current along the western Australian coast. To investigate its behaviour through time, we studied core MD002361 obtained from below the present-day pathway of the Leeuwin Current offshore the NW tip of Western Australia. Planktonic foraminifera assemblages, sea-surface temperature estimates reconstructed from those assemblages, together with the delta O-18 and delta C-13 signals of near-surface dwelling foraminifera (Globigerinoides ruber), were used to reconstruct the vertical structure of the water column for the past 500 ka. Our findings indicate that the Leeuwin Current was present along the western coastline of Australia even during glacial periods. During those times, there was a greater influence of South Indian Subtropical Water (STW) and South Indian Central Water (SICW) due to a 3-4 degrees northward migration of the Indonesian Throughflow Water/South Indian Central Water frontal system. This resulted in an overall 6-9 degrees C decrease in SST, paralleled by a thickening and greater homogeneity of the mixed layer. The increased influence of STW and SICW also suggests that the West Australian Current, which presently sits below the Leeuwin Current, was strengthened during the glacial periods and contributed to a weakening of the Leeuwin Current. Conversely, the Leeuwin Current was 'stronger' during interglacial periods due to a thicker component of Indonesian Throughflow Water sourced from the Indo Pacific Warm Pool. This was particularly the case during marine isotope stage 5.5 (MIS) and the 'super' interglacial MIS 11. (C) 2010 Elsevier B.V. All rights reserved.

ARTICLE I NFO We have examined the upper 276 cm of deep-sea core BAR9403 taken at a water depth of 2034 m offshore the southern portion of Sumatra in the eastern Indian Ocean using several micropalaeontological proxies. Faunal counts and stable isotopes of oxygen and carbon of planktic and benthic foraminifers, as well as floral counts of dinoflagellates were obtained to reconstruct conditions in the oceans over the last 35,000 years. At times, we found that when benthic foraminifers indicate high organic content values at the bottom of the ocean this is not paralleled by high productivity signals at the sea surface, but instead must relate to changes in bottom-water circulation as a result of slower water circulation. The marine isotopic stages (MIS) 3-1 are clearly differentiated by benthic and foraminiferal assemblages as well as dinoflagellates and their cysts. MIS 3 is characterised by a much sharper (than today) thermocline that was closer to the sea surface and by the absence of a low-salinity 'barrier layer' which today results from high monsoonal rains. The absence of the latter persisted during the last glacial period (MIS 2) when bottom circulation must have been reduced and high percentages of organic matter occurred on the sea floor combined with low dissolved-oxygen levels. The deglaciation is marked by a change in salinity at the sea surface as seen by the dinoflagellates and planktic foraminifers and progressive alteration of the thermocline was detected by foraminifers suggesting a less productive deep chlorophyll maximum in contrast with MIS 3 and 2. Monsoonal activity commenced around 15,000 cal years ago and was well established 2000 years later. The Holocene is marked by a significant increase in river discharge to the ocean, pulsed by the delivery of organic matter to the sea floor, despite overall oligotrophic conditions at and near the sea surface induced by a permanent low-salinity cap. We did not identify obvious and persistent upwelling conditions offshore Sumatra for the last 35,000 years.

Cool-water carbonate environments are responsible for up to one third of the carbonate sediment produced on continental shelves, and are useful modern analogues for many geologically ancient carbonate deposits. On modern and ancient high wave-energy carbonate ramps, it has been suggested that wave abrasion generally limits sediment accumulation to the outer shelf. Sediment are produced on the modern inner shelf, although few studies have investigated processes of sedimentation in these energetic environments. The Recherche Archipelago, in the west of the Great Australian Bight (GAB), was examined to better identify processes of carbonate sedimentation and preservation on extremely high energy shelves. Surficial sediments, video traverses, multibeam sonar data, cores and shallow seismics were analysed. These data reveal that the topographically varied environment of the Recherche Archipelago experienced gradual, episodic accumulation of a prograding sediment wedge, with substantially thicker deposits located on the lee side of topographic highs. Modern sediment accumulation is largely restricted to the shoreface and inner shelf, where the highly discontinuous, storm influenced blanket of Holocene sediment comprises a shore-attached quartzose sediment prism, leeward accretionary wedges and rhodolith beds above a laterally-continuous Pecten-dominated basal transgressive lag. Storm events play an important role in these environments, resulting in a mostly bare ‘shaved’ middle and outer shelf, onshore sediment transport, reworking of particles and periodic removal of sediment. The modern Recherche Archipelago is a high energy end-member of cool-water carbonate environments, in which calcareous algae dominate sediment production. Modern Esperance Bay provides a useful analogue for the interpretation of high-energy palaeoenvironments, and demonstrates that in addition to sea level change, wave energy and local geomorphology are important considerations for carbonate facies reconstructions. This study has presented new information for carbonate inner shelves that differs from classic carbonate ramp models, showing that ancient rhodolith-bearing carbonate deposits have the potential to form and be preserved in very high energy settings.

This paper details the Late Quaternary palaeoceanography of the Banda Sea based on analysis of core SHI 9016, located east of Timor. This core is located below the pathway of the Indonesian Throughflow, at a depth of 1805 m bsl. Planktonic foraminifera assemblages, the d 18 O and d 13 C of the foraminifer Globigerinoides ruber, and the total carbonate content of each

Several proxies have been developed to reconstruct past sea surface temperature (SST), but different proxies may reflect temperatures of different seasons and each proxy is characterized by certain uncertainties. Therefore, a multiproxy approach is preferred to precisely reconstruct SST. Here, we reconstruct SST of the ocean offshore southeastern Australia (Murray Canyons area) for the last ~135?ka using three independent organic proxies (TEXH86 based on glycerol dialkyl glycerol tetraethers (GDGTs), UK'37 based on alkenones, and LDI based on long-chain diols) in addition to foraminiferal faunal assemblages. The organic proxy records show similar trends, with the highest temperature (21°C for UK'37 and TEXH86, and 25°C for LDI) during the last interglacial and lowest temperature (8°C for TEXH86, 10°C for UK'37, and 12°C for LDI) during the Last Glacial Maximum. However, the differences in absolute SST estimates obtained by the organic proxies varied over time with differences of up to 9°C between LDI and TEXH86. The seasonal SST reconstructions based on the modern analogue of foraminiferal assemblages also show similar trends as the organic proxies with highest temperatures during the last interglacial (23°C for the warmest month SST, 20°C for mean annual, and 18°C for the coolest month) and lowest temperature during the Last Glacial Maximum (14°C for the warmest month, 11°C for mean annual, and 9°C for the coolest month). Down core comparison between the reconstructed SSTs of the organic and inorganic proxies shows that LDI-inferred temperatures compare well with the temperature of the warmest month, TEXH86 with the temperature of the coolest month, and UK'37 with mean annual temperature. An increase in TEXH86 SST estimates relative to those of other proxies during deglaciations and interglacials suggests that either winter temperatures rapidly warmed, possibly due to an invigoration of the Leeuwin Current over the core site, or there was a change in the growth season of the Thaumarchaeota, the source organism of GDGTs. Our study shows the benefits of a multiproxy approach in the interpretation of SST proxies, leading to a more robust knowledge of past ocean temperature changes.