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Contents Title page Publisher's notes Expedition 327 participants Expedition 327 scientists Education and outreach Operational and technical staff Abstract Introduction and background Scientific background Geological setting and earlier work Seismic studies/Site survey data Scientific objectives Site U1362 Site U1301 Site 1027 Site U1363 Education, outreach, and communication objectives Site summaries Site U1362 Site U1301 Site 1027 Site U1363 Education, outreach, and communication summary Preliminary assessment of expedition achievements Site U1362 Site U1301 Site 1027 Site U1363 Education and outreach Operations Transit from Victoria, British Columbia, to Site U1362 Site U1362 Hole U1362A Stage 1 Hole U1362B Stage 1 Hole U1362A Stage 2 Hole U1362B Stage 2 Hole U1362A Stage 3 Hole U1362A wireline logging and packer pumping test Hole U1362A CORK wellhead and casing deployment Hole U1362A CORK instrument string deployment Hole U1362B Stage 3 Hole U1362B 24 h pumping test and tracer injection experiment Hole U1362B CORK wellhead and casing deployment Hole U1362B CORK instrument string deployment Site U1301 Hole 1027C Transit to Site U1363 Hole U1363A Hole U1363B Hole U1363C Hole U1363D Hole U1363E Hole U1363F Hole U1363G Transit to Victoria, British Columbia (Canada) References Tables T1. Operations summary. T2. Hole locations. T3. Hole summary. Figures F1. Map of expedition work area. F2. Regional bathymetric map. F3. Basement relief around drill sites. F4. Heat flow, fluid flow, and temperature profiles. F5. Cross-hole responses for fluid flow, pressure, and permeability. F6. Borehole permeability estimates. F7. Seafloor installation schematic, Hole U1362A. F8. Seafloor installation schematic, Hole U1362B. F9. Summary of some shipboard results, Holes U1362A and U1301B. F10. Pumping rates and tracer concentrations. F11. CORK schematics, Holes U1362A and U1362B. F12. Sediment recovery and lithostratigraphy. F13. Examples of education and outreach activities. F14. Caliper widths and penetration rates, Holes U1362A, U1362B, and U1301B. F15. Calculated tides. PDF file |  |  | doi:10.2204/iodp.pr.327.2010 ## Abstract Integrated Ocean Drilling Program (IODP) Expedition 327 and related experiments focus on understanding fluid–rock interactions in young, upper ocean crust on the eastern flank of the Juan de Fuca Ridge, delineating the magnitude and distribution of hydrologic properties; the extent to which crustal compartments are connected or isolated (laterally and with depth); the rates and spatial extent of ridge-flank fluid circulation; and links between ridge-flank circulation, crustal alteration, and geomicrobial processes. Expedition 327 built on the achievements of IODP Expedition 301 and subsequent submersible and remotely operated vehicle (ROV) expeditions. Both drilling expeditions installed subseafloor borehole observatories ("CORKs") in basement holes to allow borehole conditions to recover to a more natural state after the dissipation of disturbances caused by drilling, casing, and other operations; provide a long-term monitoring and sampling presence for determining fluid pressure, temperature, composition, and microbiology; and facilitate the completion of active experiments to resolve crustal hydrogeologic conditions and processes. During Expedition 327, two basement holes were cored and drilled at Site U1362. Hole U1362A was cored and drilled to 528 meters below seafloor (mbsf) (292 meters subbasement [msb]), subjected to geophysical logging and hydrologic testing, and instrumented with a multilevel CORK observatory. Hole U1362B was drilled to 359 mbsf (117 msb), subjected to a 24 h pumping and tracer injection experiment, and instrumented with a single-level CORK observatory. Both CORK observatories include monitoring of pressure and temperature and downhole fluid and microbiology sampling. Wellhead samplers will be added and a long-term cross-hole test will be initiated during a postdrilling ROV expedition scheduled for Summer 2011. In addition, part of an instrument string deployed in Hole U1301B during Expedition 301 was recovered, and a replacement string of thermal sensors was installed. Finally, a program of shallow sediment coring was completed adjacent to Grizzly Bare outcrop, a suspected site of regional hydrothermal recharge. Thermal measurements and analyses of pore fluid and microbiological samples from a series of holes aligned radially from the outcrop edge will elucidate rates of fluid transport and evolution during the initial stages of ridge-flank hydrothermal circulation.