Table T1. Expedition 311 revised operations plan.

Proposed site	Location (latitude, longitude)	Seafloor depth (mbrf)	Operations description	Port call (days)	Transit (days)	Drilling/ coring (days)	Wireline logging (days)
Balboa, Panama			Start of Expedition 311	4.0 (In port)
			Transit ~3800 nmi to Astoria, Oregon @ 10.5 kt		15.1
Astoria, Oregon (USA)			Science Party boards ship in Astoria	2.0 (In port)
			Transit ~206 nmi to Site CAS-03B @ 10.5 kt		0.8
CAS-03B	48°37.058'N, 127°02.413'W	1791	Hole A: LWD/MWD to 300 mbsf (BSR @ ~230 mbsf)			1.4
			DP move ~2.8 nmi to Site CAS-02C @ 1.0 kt		0.0
CAS-02C	48°38.688'N, 126°58.993'W	2241	Hole A: LWD/MWD to 300 mbsf (BSR @ ~230 mbsf)			1.1
			DP move ~5.7 nmi to Site CAS-01B @ 1.0 kt		0.2
CAS-01B	48°41.884'N, 126°51.924'W	1336	Hole A: LWD/MWD to 380 mbsf (BSR@~215 mbsf)			1.2
			DP move ~0.8 nmi to Site CAS-06A @ 1.0 kt		0.0
CAS-06A	48°40.050'N, 126°51.053'W	1291	Hole A: LWD/MWD to 300 mbsf (BSR @ ~215 mbsf)			1.0
			DP move ~9.9 nmi to Site CAS-05D @ 1.0 kt		0.4
CAS-05D	48°47.367'N, 126°40.717'W	981	Hole A: LWD/MWD to 220 mbsf (BSR @ ~130 mbsf)			0.8
			Hole B: APC/APCT to ~200 mbsf XCB/DVTP, PCS to TD @ 220 mbsf			2.2
			Hole C: 2 APC cores, drill ahead XCB/half-cores to TD (220 mbsf) Pressure coring: PCS/HPC Logging: triple combo and FMS-sonic			2.5	0.4
			DP move ~9.9 nmi to Site CAS-06A @ 1.0 kt		0.4
CAS-06A	48°40.050'N, 126°51.053'W	1291	Hole B: APC to ~15 mbsf (2 MBIO cores)			0.3
			Hole C: APC to ~15 mbsf (2 MBIO cores)			0.1
(Active Cold Vent)			Hole D: APC/APCT to ~200 mbsf XCB/DVTP, PCS to TD (300 mbsf)			2.3
			Hole E: 2 APC cores, drill ahead XCB/half-cores to TD (300 mbsf) Pressure coring: PCS/HPC Logging: triple combo and FMS-sonic VSP: 5 m spacing (12 h)			2.9	1.0
			DP move ~0.8 nmi to Site CAS-01B @ 1.0 kt		0.1
CAS-01B	48°41.884'N, 126°51.924'W	1336	Hole B: APC to ~15 mbsf (2 MBIO cores)			0.3
			Hole C: APC to ~15 mbsf (2 MBIO cores)			0.1
(Site 889)			Hole D: APC/APCT to ~200 mbsf XCB/DVTP, PCS to TD (350 mbsf)			2.6
			Hole E: 2 APC cores, drill ahead XCB/half-cores to TD (350 mbsf) Pressure coring: PCS/HPC Logging: triple combo and FMS-sonic VSP: 5 m spacing (13 h)			3.1	1.0
			DP move ~5.7 nmi to Site CAS-02C @ 1.0 kt		0.3
Proposed site	Location (latitude, longitude)	Seafloor depth (mbrf)	Operations description	Port call (days)	Transit (days)	Drilling/ coring (days)	Wireline logging (days)
CAS-02C	48°38.688'N,| 126°58.993'W	2241	Hole B: APC/APCT to ~200 mbsf XCB/DVTP, PCS to TD (300 mbsf)			2.9
(First Slope Basin)			Hole C: 2 APC cores, drill ahead XCB/half-cores to TD (300 mbsf) Pressure coring: PCS/HPC Logging: triple combo and FMS-sonic			3.1	0.5
			DP move ~2.8 nmi to Site CAS-03B @ 1.0 kt		0.1
CAS-03B	48°37.058'N, 127°02.413'W	1791	Hole B: APC/APCT to ~200 mbsf XCB/DVTP, PCS to TD (300 mbsf)			2.7
			Hole C: 2 APC cores, drill ahead XCB/half-cores to TD (300 mbsf) Pressure coring: PCS/HPC Logging: triple combo and FMS-sonic			3.0	0.5
			Transit ~134.0 nmi to Victoria @ 10.5 kt		0.6
Victoria, B.C., Canada			End of Expedition 311		18.0	33.6	3.4
			Subtotal transit time:		18.0
			Subtotal on site time:		37.0
			Total operating days:		55.0
			Total expedition including 6.0 days of port call(s):		61.0

Notes: DP = dynamic positioning. LWD = logging while drilling, MWD = measurement while drilling. BSR = bottom-simulating reflector, TD = total depth. APC = advanced piston corer, XCB = extended core barrel. APCT = APC temperature tool, DVTP = Davis-Villinger Temperature Probe. PCS = pressure coring sampler, HPC = HYACINTH pressure corer. Triple combo = triple combination tool string, FMS = Formation MicroScanner. VSP = vertical seismic profile. MBIO = microbiology sample. Seafloor depth is prospectus water depth + 11.0 m adjustment from water line to rig floor (i.e., drillers depth). Astoria is shown as a 2 day port call due to timing of port entry (crossing the Columbia Bar) and possibly increasing loading issues. Each deep cored hole has 16 h contingency to allow for hole instability, H₂S, and hydrate handling slow-downs.

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