Contingency plans

Contingency operational options

Details of possible operational priorities or contingencies will be decided by the Co-Chief Scientists, EPMs, and Operation Superintendents according to operational realities aboard ship. To date, the NanTroSEIZE PMT has defined three viable contingency options; the first two options are described above as part of the riser operations strategy:

  • Recovering temporary monitoring instruments and redeploying replacement sensors (GeniusPlug) in IODP Hole C0010A;

  • Coring Hole C0002F beyond 3600 mbsf; and

  • Logging, cuttings, mud gas analysis, and casing to 4400 mbsf in Hole C0002F.

Site C0010 is located 3.5 km north of IODP Site C0004 and was first drilled during Expedition 319 (Expedition 319 Scientists, 2010). Operations during that expedition included drilling through a shallow branch of the megasplay fault zone and into its footwall using LWD, setting casing with screens spanning the fault zone, and installing a temporary suite of pressure and temperature sensors (a SmartPlug) to monitor within the fault zone. Major lithologic boundaries as well as the location of the splay fault at ~407 mbsf were identified in LWD data and were used to select a depth interval spanning the fault for placement of the two screened casing joints. During Expedition 332 (Expedition 332 Scientists, 2011), the SmartPlug was recovered and replaced with a modified instrument package (the GeniusPlug), which includes a set of geochemical and biological experiments in addition to the pressure and temperature sensors. If conditions and time allow during Expedition 348, this temporary instrument package will be recovered and replaced with a new GeniusPlug.