Site summaries (continued)

Site SCS-3G

Priority: Primary
Position: 15°22.548′N, 117°0.0′E
Water depth (m): 4213
Target drilling depth (mbsf): 1061
Approved maximum penetration: Approved to basement + 100 m (Estimated total depth = 1061 mbsf)
Survey coverage (track map; seismic profile): Bathymetric sketch and site track map (Fig. AF10, AF11) Deep-penetration seismic reflection:
• Primary line: 973SCSIO01e (CDP59300) (Fig. AF12)
• Crossing line: SO49-017a (projected at CDP10867) (Fig. AF13)
Objectives: • Determine the age of the East Sub-basin
• Date the timing of seafloor spreading cessation in the South China Sea
• Test if the East Sub-basin formed in an area floored by older oceanic crust
• Measure magnetization, mineralization, and geochemical compositions of basement rocks
• Obtain basement rocks to ascertain the causes of sharp magnetic contrasts between different sub-basins
• Study the paleoceanographic response to the opening of the South China Sea
Drilling program: Hole A:
• APC to refusal with nonmagnetic core barrels, core orientation (FlexIT tool), and APCT-3
• XCB to refusal
• Drop FFF
• RCB with nonmagnetic core barrels to 1061 mbsf
Downhole logging program: • Triple combo
• FMS-sonic
Nature of rock anticipated: (Calcareous) mudstone, siltstone, sandstone, basalt