SITE: SWPAC-1C
PRIORITY: 1
POSITION: 44°45.33'S, 172°23.5'E
WATER DEPTH: 420 m
SEDIMENT THICKNESS: >2000 m
TOTAL PENETRATION: 500 m
SEISMIC COVERAGE: Line CB-82-22
Objectives: Determine the Cenozoic history of shallow WBC and associated drift formation, evaluate late Miocene changes in sea level.
Drilling Program: APC, XCB
Logging and Downhole Operations: Triple-combo, FMS/Sonic, GHMT.
Nature of Rock Anticipated: Terrigenous silts and muds.
SITE: SWPAC-2A
PRIORITY: 1
POSITION: 42°56.664'S, 177°33.40'W
WATER DEPTH: 595 m
SEDIMENT THICKNESS: ~1200 m
TOTAL PENETRATION: 520 m
SEISMIC COVERAGE: SCS high resolution seismic Mobile 72-211; SCS deep penetration; 3.5 and 12 kHz lines
Objectives: Test the record of circum-Antarctic flow against the Milankovitch orbital model, including estimates of simultaneity with Northern Hemisphere records. Obtain high-resolution oxygen isotope record of Eocene/Oligocene. Determine paleoproductivity and location of STC and paleohydrography of AAIW.
Drilling Program: APC, XCB
Logging and Downhole Operations: Triple-combo, FMS/Sonic, GHMT.
Nature of Rock Anticipated: Hemipelagites, carbonate pelagites
SITE: SWPAC-5A
PRIORITY: 1
POSITION: 41°47.178'S, 171°29.95'W
WATER DEPTH: 3308 m
SEDIMENT THICKNESS: 860 m
TOTAL PENETRATION: 700 m
SEISMIC COVERAGE:
SCS high resolution seismic, NZOI CR2050, 3.5 and 12 kHz data from CR2050
Objectives: Test coherence of paleoclimatic record with Milankovich cycles. Determine the evolution of circum-Antarctic ocean circulation, including periods when the boundary current component may have extended into shallow depths or reversed. Evaluate grain-size signals (flow speed) to determine water mass movement to estimate the velocity behavior of the DWBC. Determine paleoproductivity and location of STC and paleohydrography of CDW (including NADW component).
Drilling Program: APC, XCB
Logging and Downhole Operations: Triple-combo, FMS/Sonic, GHMT
Nature of Rock Anticipated: Hemipelagites, carbonate pelagites
SITE: SWPAC-6B
PRIORITY: 1
POSITION: 50°03.80'S, 173°22.296'E
WATER DEPTH: 750 m
SEDIMENT THICKNESS: ~700 m
TOTAL PENETRATION: 500 m
SEISMIC COVERAGE: SCS high resolution seismic, 3.5 and 12 kHz data
Objectives: Determine the evolution of circum-Antarctic ocean circulation, including periods when the boundary current component may have extended into shallow depths or reversed. Determine the behavior of low salinity AAIW. Stable isotope analyses to outline water mass and productivity variability through mid-Oligocene.
Drilling Program: APC, XCB
Logging and Downhole Operations: Triple-combo, FMS/Sonic, GHMT.
Nature of Rock Anticipated: Calcareous biopelagites
SITE: SWPAC-7A
PRIORITY: 1
POSITION: 50°54.252'S, 177°00.30'E
WATER DEPTH: 4490 m
SEDIMENT THICKNESS: 840 m
TOTAL PENETRATION: 450 m
SEISMIC COVERAGE: SCS high resolution seismic
Objectives: Determine history of CDW incursions into SW Pacific. Evaluate grain-size signals (flow speed) to determine water mass movement at this site to estimate the velocity behavior of the DWBC. This site will be important for assessing the extent to which the ACC acts as a driving force for CDW inflow.
Drilling Program: APC, XCB
Logging and Downhole Operations: Triple-combo, FMS/Sonic, GHMT.
Nature of Rock Anticipated: Sand and Mn nodules on surface. Siliceous ooze and red clay.
SITE: SWPAC-8A
PRIORITY: 1
POSITION: 46°34.36'S, 177°24.05'W
WATER DEPTH: 4460 m
SEDIMENT THICKNESS: --
TOTAL PENETRATION: 650 m
SEISMIC COVERAGE: SCS high resolution seimic NZOI Lines CR2023, CR2040, and CR1151; 3.5 and 12 kHz data
Objectives: Determine climate, sea level, and tectonic controls on abyssal sediment supply. Test deep-sea cyclotherm model. Evaulate late Miocene to Holocene sediment injection into DWBC. This site in combination with the most southerly drift sites (Sites SWPAC-6B, 7A) will allow us to assess the shift in position of the climatically important AAC and SAF fronts using faunal and coarse-fraction analysis and stable isotopic and magnetic susceptibility measurements to trace ice-rafted detritus.
Drilling Program: APC, XCB
Logging and Downhole Operations: Triple-combo, FMS/Sonic, GHMT.
Nature of Rock Anticipated: Terrigenous silt/mud turbidites, hemipelagites
SITE: SWPAC-9A
PRIORITY: 1
POSITION: 39°29.898'S, 176°33.87'W
WATER DEPTH: 3940 m
SEDIMENT THICKNESS: --
TOTAL PENETRATION: 450 m
SEISMIC COVERAGE: SCS high resolution seimic, 3.5 and 12 kHz data
Objectives: Determine (1) Miocene evolution of DWBC and associated water masses, (2) abyssal sediment budget, and (3) paleovolcanic history of the Neogene.
Drilling Program: APC, XCB
Logging and Downhole Operations: Triple-combo, FMS/Sonic, GHMT.
Nature of Rock Anticipated: Terrigenous and siliceous mud, tephra
SITE: SWPAC-3A
PRIORITY: 2
POSITION: 42°33'S, 178°10'W
WATER DEPTH: 1320 m
SEDIMENT THICKNESS: --
TOTAL PENETRATION: 625 m
SEISMIC COVERAGE:
Objectives: Alternate for SWPAC-2A.
Drilling Program: APC
Logging and Downhole Operations: Triple-combo, FMS/Sonic, GHMT.
Nature of Rock Anticipated: Biosiliceous and carbonate sediments with variable amounts of clay and ice-rafted debris.
SITE: SWPAC-10B
PRIORITY: 2
POSITION: 45°40.0'S, 176°17.7'W
WATER DEPTH: 3940 m
SEDIMENT THICKNESS: --
TOTAL PENETRATION: 450 m
SEISMIC COVERAGE:
Objectives: Alternate for SWPAC-8A.
Drilling Program: APC
Logging and Downhole Operations: Triple-combo, FMS/Sonic, GHMT.
Nature of Rock Anticipated: Biosiliceous and carbonate sediments with variable amounts of clay and ice-rafted debris.
SITE: SWPAC-16A
PRIORITY: 2
POSITION: 42°25.0'S, 167°20.0'W
WATER DEPTH: 4870 m
SEDIMENT THICKNESS: --
TOTAL PENETRATION: 480 m
SEISMIC COVERAGE:
Objectives: Alternate for SWPAC-9A and -5A.
Drilling Program: APC
Logging and Downhole Operations: Triple-combo, FMS/Sonic, GHMT.
Nature of Rock Anticipated: Biosiliceous and carbonate sediments with variable amounts of clay and ice-rafted debris.