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The Indonesian Throughflow (ITF) is a critical part of the global thermohaline conveyor. It plays a key role in transporting heat from the equatorial Pacific (the Indo-Pacific Warm Pool) to the Indian Ocean and exerts a major control on global climate. The complex tectonic history of the Indonesian archipelago, a result of continued northward motion and impingement of the Australasian plate into the southeast Asian part of the Eurasian plate, makes it difficult to reconstruct long-term (i.e., million year) ITF history from sites within the archipelago. The best areas to investigate ITF history are downstream in the Indian Ocean, either in the deep ocean away from strong tectonic deformation or along proximal passive margins that are directly under the influence of the ITF. Although previous Ocean Drilling Program and Deep Sea Drilling Project deep-water cores recovered in the Indian Ocean have been used to chart Indo-Pacific Warm Pool influence and, by proxy, ITF variability, these sections lack direct biogeographic and sedimentological evidence of the ITF. International Ocean Discovery Program Expedition 356 cored seven sites covering a latitudinal range of 29°S–18°S off the northwest coast of Australia to obtain a 5 My record of the ITF, Indo-Pacific Warm Pool, and climate evolution that has the potential to match orbital-scale deep-sea records in its resolution. The material recovered will allow us to describe the history of the Australian monsoon and its variability, a system whose genesis is thought to be related to the initiation of the East Asian monsoon and is hypothesized to have been in place since the Pliocene or earlier. It also will lead to a better understanding of the nature and timing of the development of aridity on the Australian continent. Detailed paleobathymetric and stratigraphic data from the transect will also allow subsidence curves to be constructed to constrain the spatial and temporal patterns of vertical motions caused by the interaction between plate motion and convection within the Earth’s mantle, known as dynamic topography. The northwest shelf is an ideal location to study this phenomenon because it is positioned on the fastest moving continent since the Eocene, on the edge of the degree 2 geoid anomaly. Accurate subsidence analyses over 10° of latitude can resolve whether northern Australia is moving with or over either a time-transient or long-term stationary downwelling within the mantle, thereby vastly improving our understanding of deep-Earth dynamics and their impact on surficial processes. 

The Indonesian Throughflow (ITF) is a critical part of the global thermohaline conveyor. It plays a key role in transporting heat from the equatorial Pacific (the Indo-Pacific Warm Pool) to the Indian Ocean and exerts a major control on global climate. The complex tectonic history of the Indonesian archipelago, a result of continued northward motion and impingement of the Australasian plate into the southeast Asian part of the Eurasian plate, makes it difficult to reconstruct long-term (i.e., million year) ITF history from sites within the archipelago. The best areas to investigate ITF history are downstream in the Indian Ocean, either in the deep ocean away from strong tectonic deformation or along proximal passive margins that are directly under the influence of the ITF. Although previous Ocean Drilling Program and Deep Sea Drilling Project deepwater cores recovered in the Indian Ocean have been used to chart Indo-Pacific Warm Pool influence and, by proxy, ITF variability, these sections lack direct biogeographic and sedimentological evidence of the ITF. International Ocean Discovery Program Expedition 356 cored seven sites covering a latitudinal range of 29°S–18°S off the northwest coast of Australia to obtain a 5 My record of ITF, Indo-Pacific Warm Pool, and climate evolution that has the potential to match orbital-scale deep-sea records in its resolution. The material recovered will allow us to describe the history of the Australian monsoon and its variability, a system whose genesis is thought to be related to the initiation of the East Asian monsoon and is hypothesized to have been in place since the Pliocene or earlier. It also will lead to a better understanding of the nature and timing of the development of aridity on the Australian continent. Detailed paleobathymetric and stratigraphic data from the transect will also allow subsidence curves to be constructed to constrain the spatial and temporal patterns of vertical motions caused by the interaction between plate motion and convection within the Earth’s mantle, known as dynamic topography. The northwest shelf is an ideal location to study this phenomenon as it is positioned on the fastest moving continent since the Eocene, on the edge of the degree 2 geoid anomaly. Accurate subsidence analyses over 10° of latitude can resolve whether northern Australia is moving with or over either a time-transient or long-term stationary downwelling within the mantle, thereby vastly improving our understanding of deep-Earth dynamics and their impact on surficial processes. 

The Indonesian Throughflow (ITF) is a critical part of the global thermohaline conveyor. It plays a key role in transporting heat from the equatorial Pacific (the Indo-Pacific Warm Pool) to the Indian Ocean and exerts a major control on global climate. The complex tectonic history of the Indonesian archipelago, a result of continued northward motion and impingement of the Australasian plate into the southeast Asian part of the Eurasian plate, makes it difficult to reconstruct long-term (i.e., million year) ITF history from sites within the archipelago. The best areas to investigate ITF history are downstream in the Indian Ocean, either in the deep ocean away from strong tectonic deformation or along proximal passive margins that are directly under the influence of the ITF. Although previous Ocean Drilling Program and Deep Sea Drilling Project deep-water cores recovered in the Indian Ocean have been used to chart Indo-Pacific Warm Pool influence and, by proxy, ITF variability, these sections lack direct biogeographic and sedimentological evidence of the ITF. International Ocean Discovery Program Expedition 356 cored seven sites covering a latitudinal range of 29°S–18°S off the northwest coast of Australia to obtain a 5 My record of the ITF, Indo-Pacific Warm Pool, and climate evolution that has the potential to match orbital-scale deep-sea records in its resolution. The material recovered will allow us to describe the history of the Australian monsoon and its variability, a system whose genesis is thought to be related to the initiation of the East Asian monsoon and is hypothesized to have been in place since the Pliocene or earlier. It also will lead to a better understanding of the nature and timing of the development of aridity on the Australian continent. Detailed paleobathymetric and stratigraphic data from the transect will also allow subsidence curves to be constructed to constrain the spatial and temporal patterns of vertical motions caused by the interaction between plate motion and convection within the Earth’s mantle, known as dynamic topography. The northwest shelf is an ideal location to study this phenomenon because it is positioned on the fastest moving continent since the Eocene, on the edge of the degree 2 geoid anomaly. Accurate subsidence analyses over 10° of latitude can resolve whether northern Australia is moving with or over either a time-transient or long-term stationary downwelling within the mantle, thereby vastly improving our understanding of deep-Earth dynamics and their impact on surficial processes. 

This chapter documents the procedures and methods used in the shipboard laboratories during International Ocean Discovery Program (IODP) Expedition 356. This introductory section provides a rationale for the site locations and an overview of IODP depth conventions, curatorial procedures, and general core handling/analyses during Expedition 356. Subsequent sections describe specific laboratory procedures and instruments in more detail. This information only applies to shipboard work described in this Proceedings volume; methods used in shore-based analyses of Expedition 356 samples and/or data will be described in various scientific contributions in the open peer-reviewed literature and the Expedition research results section of this volume. 

International Ocean Discovery Program (IODP) Site U1459 lies in the northern part of the Perth Basin, about 1 nmi seaward of Site U1458 and the Houtman-1 industry well on the northern Rottnest shelf (James et al., 1999; Collins et al., 2014). Site U1459 was originally intended as an alternate to IODP Site U1458. The ship moved to Site U1459 after having difficulty coring the uppermost sediments at Site U1458. Like U1458, Site U1459 is directly seaward of and downdip from the Houtman Abrolhos main reef complex, which contains the most southerly tropical reefs in the Indian Ocean. Sites U1458 and U1459 represent the southernmost sites of our latitudinal transect (Figures F1, F2, F3). 

International Ocean Discovery Program (IODP) Site U1460 lies in the northern part of the Perth Basin, about 18 nmi north of IODP Site U1459 and ~150 m from the Morangie-1 industry well on the Carnarvon ramp (James et al., 1999; Collins et al., 2014). Site U1460 is north of the Houtman Abrolhos main reef complex, which contains the most southerly tropical reefs in the Indian Ocean (Figures F1, F2, F3). 

International Ocean Discovery Program (IODP) Site U1461 is 100 km northwest of Barrow Island in the Northern Carnarvon Basin, ~150 m from the West Tryal Rocks-2 industry well (Figure F1). Site U1461 is on the shelf edge of an outer ramp (James et al., 2004). The seabed in the region is poorly sorted carbonate-rich (>90%) sediment made up of bioclastic gravel, sand, and mud (Jones, 1973; James et al., 2004). Coring at Site U1461 targeted a 1 km thick outer shelf to upper slope carbonate wedge that onlaps (because of basin-wide subsidence) a regional top Miocene surface (Figures F2, F3). 

International Ocean Discovery Program (IODP) Site U1462 is 50 km north of the Montobello Islands in the Northern Carnarvon Basin, ~150 m from the Fisher-1 industry well (Figures F1, F2). Site U1462 is on the outer edge (87 m water depth) of a middle ramp (James et al., 2004). The seabed in the region is carbonate-rich (>90%) gravel and sand with minor mud (Jones, 1973; James et al., 2004). Coring at Site U1462 targeted a sequence of shelfal to shelf-edge carbonates that overlie a Miocene sand unit (the Bare Formation) (Figure F3). 

At 270 m water depth, International Ocean Discovery Program (IODP) Site U1464 is currently in an outer ramp setting (James et al., 2004), ~50 km southeast of the Rowley Shoals (Figures F1, F2). The seabed in the vicinity of the site is poorly sorted, carbonate-rich (>90%) sediment made up of bioclastic gravel, sand, and mud (Jones, 1973; James et al., 2004). Site U1464 is 5 km updip from a drowned “fossil” shoal described by Jones (1973) and Ryan et al. (2009) and is connected to the site by parallel laterally persistent reflectors on seismic Profile JN87-07 (Figure F3). Therefore, improved ages for these reflectors may allow us to date the initiation and demise of this reef/shoal.