Table T1. Expedition 338 operations and time estimates.
| Operation |
Depth (mbsf) |
Days |
Subtotal (d) |
Total (d) |
|---|---|---|---|---|
| Transit, deploy transponders, retrieve corrosion cap, preparation for spud | — | 5.0 | 5.0 | 5.0 |
| Run and set BOP and riser, test BOP | — | 11.0 | 11.0 | 16.0 |
| Set 16 inch casing | ||||
| DOC and LOT | 850 | 2.0 | ||
| Drill RWD (LWD) to 2300 mbsf | 2300 | 9.0 | ||
| Run and cement 16 inch casing | 2300 | 6.0 | ||
| Test BOP | — | 2.0 | 19.0 | 35.0 |
| Set 13-3/8 inch casing | ||||
| DOC and LOT | 2300 | 2.0 | ||
| Cut core from 2300 to 2400 mbsf | 2400 | 4.0 | ||
| Underream (LWD) to 17 inch hole from 2300 to 3600 mbsf | 3600 | 16.0 | ||
| Run and cement 13-3/8 inch casing to 3600 mbsf | 3600 | 6.0 | ||
| Test BOP (2 times) | — | 4.0 | 32.0 | 67.0 |
| Suspend hole | ||||
| Set cement plug or bridge plug in hole | — | 3.0 | ||
| Retrieve BOP and marine riser | — | 9.0 | 12.0 | 79.0 |
| Set corrosion cap, retrieve transponders | — | 2.0 | 3.0 | 82.0 |
| Transit to Shingu | — | 1.0 | ||
| Contingency | — | 20.0 | 20.0 | 102.0 |
| Mechanical down time (operation time × 3%) | ||||
| Wait on weather (operation time × 1.5%) | ||||
| Typhoon evacuation (4 times × 4 days) |
Water depth = 1968 m. BOP = blowout preventer. DOC = drill out cement. LOT = leak-off test. RWD = reaming while drilling, LWD = logging while drilling.