Table T2. Leg 210 operations plan and time estimate for alternate sites.
| Site | Location (lat/long) |
Water depth (mbrf) |
Operations description | Transit (days) |
Drilling (days) |
Logging (days) |
| NNB-03A | 45.3267°N | 4553 | Two casing strings (reentry cone, 20, and 16 in) | |||
| (2 casings) | 44.6317°W | with 10-3/4-in liner as contingency | ||||
| Hole A: drill-in 80 m 20-in casing with reentry cone | 1.8 | |||||
| Drill with 22-in underreamer ~80 to 500 mbsf | ||||||
| set 475 m 16-in casing, cement | 4.8 | |||||
| RCB 500-1240 mbsf (sediment) | 8.2 | |||||
| RCB 1240-1340 mbsf (basement at 1240 mbsf) | 3.5 | |||||
| Log: triple combo/FMS-sonic/WST-VSP | 2.2 | |||||
| SUBTOTAL: | 0.0 | 18.3 | 2.2 | |||
| TOTAL OPERATING DAYS (56 days available): | 20.5 | |||||
| NNB-03A ALTERNATE OPERATIONS: | ||||||
| NNB-03A | 4553 | Hole A: underream to 18-in ~525 to 1240 mbsf | ||||
| (3 casings) | and set 740 m 10-3/4-in liner @ 1215 mbsf, cement | 5.5 | ||||
| Hole A: RCB basement 1240-1480 mbsf | 11.8 | |||||
| Log: triple combo/FMS-sonic/WST-VSP | 1.7 | |||||
| Hole B: APC to refusal ~250 mbsf, XCB to refusal ~500 mbsf | 4.7 | |||||
| Log: triple combo/FMS-sonic | 1.4 | |||||
| NNB-01B | 45.3917°N | 4563 | Three casing strings (reentry cone, 20, 16, and 13-3/8 in) | |||
| (3 casings) | 44.7583°W | with 10-3/4-in casing as contingency | ||||
| Hole A: drill-in 60 m 20-in casing with reentry cone | 1.8 | |||||
| Drill with 20-in underreamer ~60 to 800 mbsf | ||||||
| set 775 m 16-in casing, cement | 6.2 | |||||
| RCB 800-1375 mbsf | 7.7 | |||||
| Log: triple combo/FMS-sonic/WST-VSP | 2.0 | |||||
| Underream with 14-3/4-in tricone bit ~800 to 1375 mbsf | ||||||
| and set 725 m 13-3/8-in liner @ 1350 mbsf, cement | 6.5 | |||||
| RCB sediment 1375-2180 mbsf | 17.7 | |||||
| RCB basement 2180-2280 mbsf | 4.3 | |||||
| Log: triple combo/FMS-sonic/WST-VSP | 2.3 | |||||
| SUBTOTAL: | 0.0 | 44.2 | 4.3 | |||
| TOTAL OPERATING DAYS (56 days available): | 48.5 | |||||
| NNB-01C | 45.4661°N | 4412 | Three casing strings (reentry cone, 20, 16, and 13-3/8 in) | |||
| (3 casings) | 44.9050°W | with 10-3/4-in casing as contingency | ||||
| Hole A: drill-in 60 m 20-in casing with reentry cone | 1.8 | |||||
| Drill with 20-in underreamer ~60 to 800 mbsf | ||||||
| set 775 m 16-in casing, cement | 6.2 | |||||
| RCB 800-1375 mbsf | 7.7 | |||||
| Log: triple combo/FMS-sonic/WST-VSP | 2.0 | |||||
| Underream with 14-3/4-in tricone bit ~800 to 1375 mbsf | ||||||
| and set 725 m 13-3/8in liner @ 1350 mbsf, cement | 6.4 | |||||
| RCB sediment 1375-2360 mbsf | 21.8 | |||||
| RCB basement 2360-2460 mbsf | 4.3 | |||||
| Log: triple combo/FMS-sonic/WST-VSP | 2.3 | |||||
| SUBTOTAL: | 0.0 | 48.2 | 4.3 | |||
| TOTAL OPERATING DAYS (56 days available): | 52.5 | |||||
| NNB-04A | 45.1967°N | 4624 | Hole A: RCB 0-135 m (sediment) | |||
| 44.3767°W | RCB 135-235 m (basement at 135 mbsf) | 4.7 | ||||
| Log: triple combo/FMS-sonic/WST-VSP | 1.4 | |||||
| SUBTOTAL: | 0.0 | 4.7 | 1.4 | |||
| TOTAL OPERATING DAYS (56 days available): | 6.1 | |||||
| NNB-05A | 45.1967°N | 4695 | Hole A: APC to 250 mbsf, XCB to 355 mbsf | 3.4 | ||
| 44.3767°W | Hole B: drill ahead 335 mbsf, | |||||
| RCB 335 to 435 mbsf (basement at 355 mbsf) | 4.9 | |||||
| Log: triple combo/FMS-sonic/WST | 1.7 | |||||
| SUBTOTAL: | 0.0 | 8.3 | 1.7 | |||
| TOTAL OPERATING DAYS (56 days available): | 10.0 | |||||
| NNB-06B | 45.1033°N | 4727 | Hole A: APC to 250 mbsf, XCB to 500 mbsf | 4.6 | ||
| 44.1967°W | Hole B: drill ahead 490 mbsf, | |||||
| RCB 490 to 858 mbsf (basement at 758 mbsf) | 7.5 | |||||
| Log: triple combo/FMS-sonic/WST | 1.8 | |||||
| SUBTOTAL: | 0.0 | 12.1 | 1.8 | |||
| TOTAL OPERATING DAYS (56 days available): | 13.9 |