Priority:
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Primary
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Position:
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Site 1 = 145°47.7649′E, 15°22.6093′S
Site 2 = 145°47.7929′E, 15°22.6519′S
Site 3 = 145°47.8483′E, 15°22.7075′S
Site 4 = 145°47.8744′E, 15°22.7508′S
Site 5 = 145°47.8825′E, 15°22.8768′S
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Water depth (m):
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Site 1 = 54.6
Site 2 = 46.5
Site 3 = 70
Site 4 = 75
Site 5 = 198.7
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Target drilling depth (mbsf):
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Site 1 = 50 m terrace
Site 2 = 50 m reef
Site 3 = 70 m terrace
Site 4 = 70 m reef
Site 5 = fore-reef slope (upper slope)
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Approved maximum penetration (mbsf):
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260
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Survey coverage:
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Seismic:
• High-resolution sparker seismic reflection data (collected September–October 2007, SS07 cruise).
• Topas PS18 seismic reflection data (collected September–October 2007, SS07 cruise).
• 3.5 kHz chirp data (collected December 2005, RV James Kirby cruise; see Beaman et al., 2007).
Swath bathymetry/backscatter:
• Reson 8110 swath bathymetry and backscatter, 5 m grid (collected December 2005, RV James Kirby cruise; see Beaman et al., 2007).
• EM300 swath bathymetry and backscatter, 10 m grid (collected September–October 2007, SS07 cruise).
Imagery:
• Submersible (Platypus) and remotely operated vehicle [ROV] dive photographs available.
• AUV stereographic imagery available from one dive during the SS07 cruise.
Sampling:
• 90 and 210 m long drill cores from Boulder Reef and Ribbon Reef 5 sites (International Consortium for Great Barrier Reef Drilling; Webster and Davies, 2003).
• Sites 819–821 (Grafton Passage); Site 822 (offshore Cairns).
• Three carbonate rocks sampled from the 50 m reef by deep divers in 2007; two rock dredges that recovered reef limestones during the SS07 cruise.
Other:
• Magnetics (Grafton Passage and offshore Cairns).
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Objective
(see text for details):
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To establish course of postglacial sea level rise at the GBR (i.e., to define the exact shape of the deglaciation curve for the period 20,000 to 10,000 cal. y BP).
To define short-term paleoclimatic changes, especially SST variations, for the region over the last 20,000 y.
To analyze the impact of sea level changes on reef growth, geometry, and biological makeup.
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Drilling, coring, and downhole measurement program:
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Logging program: borehole diameter, spectral natural gamma ray, resistivity-induction, acoustic velocity, borehole optical and acoustic images, borehole hydrogeological properties.
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Anticipated lithology:
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Sediments: limestones and unconsolidated sands.
Basement: limestones.
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