The second hole of the site was spudded with the APC at 1710 hr on 2 September. The sea-floor depth inferred from recovery was 4487.9 mbsl. APC coring advanced to 23.0 mbsf when Core 181-1121B-3H did not achieve a full stroke. The XCB barrel was run in with a soft formation cutting shoe and experienced considerable difficulty advancing with high torque and a very low penetration rate. After advancing only 0.5 m in 30 min of rotation, the core barrel was recovered to investigate why the coring was so difficult. The core proved to contain chert fragments. A hard-formation cutting shoe was deployed, and coring continued with the XCB in slow and occasionally difficult conditions.
XCB coring deepened the hole to 139.7 mbsf when operations were terminated because the
scientific objectives were reached. The bit cleared the seafloor at 0120 hr on 4 September, ending
operations at Hole 1121B. The bit was at the plane of the rotary table at 1040 hr and by 1045 hr the
drilling equipment was secured for the voyage to the next site. Both beacons were recalled and
recovered. At 1045 hr on 4 September, the vessel was under way on a northeasterly course to Site
To 181 Summary of Engineering and Drilling Operations: Site 1122
To 181 Table of Contents