Priority:
|
Primary
|
Position:
|
Site 1 = 145°49.1785′E, 15°28.267′S
Site 2 = 145°49.2832′E, 15°28.3262′S
Site 3 = 145°49.3637′E, 15°28.3295′S
Site 4 = 145°49.4254′E, 15°28.332′S
|
Water depth (m):
|
Site 1 = 47.5
Site 2 = 61.6
Site 3 = 70.4
Site 4 = 105.9
|
Target drilling depth (mbsf):
|
Site 1 = 50 m reef
Site 2 = 70 m terrace
Site 3 = 70 m reef
Site 4 = 100 m reef
|
Approved maximum
penetration (mbsf):
|
160
|
Survey coverage:
|
Seismic:
• High-resolution sparker seismic reflection data (collected September–October 2007, SS07 cruise).
• Topas PS18 seismic reflection data (collected September–October 2007, SS07 cruise).
Swath bathymetry/backscatter:
• EM300 swath bathymetry and backscatter, 10 m grid (collected September–October 2007, SS07 cruise).
Imagery:
• None
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).
|
Objective
(see text for details):
|
To establish the 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.
|
Drilling, coring, and downhole measurement program:
|
Logging program: borehole diameter, spectral natural gamma ray, resistivity-induction, acoustic velocity, borehole optical and acoustic images, borehole hydrogeological properties.
|
Anticipated lithology:
|
Sediments: limestones and unconsolidated sands.
Basement: limestones.
|
