IODP

doi:10.2204/iodp.sp.315.2007

Site summaries (continued)

Proposed Site NT1-07A
Priority:
Primary:
Chikyu Expedition 314 (LWD)
Alternate:
• Other Stage 1 expeditions
Position:
32°49.7300′N, 136°52.8900′E
Water depth (m):
4062
Target drilling depth (mbsf):
1200 m sediment (stop at basement contact)
Approved maximum penetration (mbsf):
1400; approved by CDEX and TAMU safety panels based on EPSP Jan 2007 recommendation
Survey coverage:
Extensive survey data outlined in Proposal 603A-Full2 (www.iodp.org/nantroseize-downloads):
• Track maps (Figs. AF20, AF4)
• Line odkm 03-101 SP 2524 (Fig. AF21)
• IFREE 3-D InLine 95 (Figs. AF5, AF22)
Objective
(see text for full details):
Reference site:
• Penetrate entire sedimentary section
• Complete characterization of Shikoku Basin strata and upper igneous basement where basement topography is relatively flat and the lower Shikoku Basin sand facies is well-developed
• Document lithologic, hydrologic, thermal, geotechnical, and geochemical properties of subduction inputs
• Log-seismic integration
Drilling, coring, and downhole measurement program:
Chikyu Expedition 314 (LWD):
Hole A - MWD/LWD to basement contact
Anticipated lithology:
0–400 mbsf: upper Shikoku Basin hemipelagics and volcanic ash
400–800 mbsf: lower Shikoku Basin hemipelagics and volcanic ash
800–1200 mbsf: lower Shikoku Basin hemipelagics and turbidite sands
>1200 mbsf: volcaniclastic sediments and basalt