Figure F8. Cartoon illustrating selected features of the three CORK borehole observatory systems installed during Expedition 301. Approximate total depths (TD) listed in meters subbasement (msb) are correct as shown, but drawings are not to scale and do not indicate precise locations of casing, cones, packers, sampling and monitoring lines, or downhole instruments. Hole 1026B was created during Leg 168, whereas Holes U1301A and U1301B were created during Expedition 301. All three CORKs monitor multiple depth intervals. The CORKs in Holes 1026B and U1301A monitor shallowest basement and the zone between the casing packer and the seafloor CORK seal. The CORK in Hole U1301B monitors three basement intervals, with the uppermost interval extending to the seafloor seal. Instruments deployed at depth in all three CORK systems include OsmoSamplers for fluid chemistry, microbiological growth substrate, and autonomous temperature loggers distributed within basement. See Fisher et al. (this volume) and the "Site U1301" and "Site 1026" chapters for additional details regarding CORK configuration and deployment.