After leaving Peruvian waters, the vessel proceeded to a rendezvous point in the Gulf of Guayaquil, Ecuador, to pick up Juan Carlos Tapia, the Ecuadorian observer, and an Ocean Drilling Program (ODP) engineer, Dean Ferrell. Because of limited accommodations, the Peruvian observer, Robert Herrera, could not remain on the ship. The Bell 206B III helicopter chartered by the Ecuadorian agent had limited range and lacked radar (it used a Global Positioning System receiver for navigation). The vessel was therefore required to divert course and wait on a location no farther than 20 mi from land (south of Salinas; 2.5°S, 81.0°W; 100 m bathymetric contour). The vessel entered Ecuadorian waters at 1515 hr on 4 May 2002 and by 0730 hr on 5 May was positioned 2 mi south of the rendezvous location. The 889-nmi transit required 77.5 hr at an average speed of 11.5 kt. The helicopter landed at 0922 hr and left the JOIDES Resolution at 0946 hr.
After a transit of 114 nmi to the west-northwest, the vessel reached Site 1238 (proposed Site CAR-2C) by 2005 hr on 5 May. The 3.5-kHz precision depth recorder (PDR) was used as a final check of site characteristics by comparison to precruise survey data.
After the drill string was deployed to a depth of 2209 meters below rig floor (mbrf), Hole 1238A was initiated with the advanced piston corer (APC) at 0150 hr on 6 May. The seafloor depth was estimated at 2213.5 mbrf by the amount of recovery in the first core (3.9 m shallower than the corrected PDR depth). Piston coring advanced to 90.5 meters below seafloor (mbsf), where a stuck core barrel (Core 10H) required drilling over to release the barrel from the sediment. The next piston core barrel came free with an excess force of 60 klb. Cores 12H through 21H (100.0-195.0 mbsf) had to be drilled over. Piston coring in the hole was terminated when the last piston Core 22H (195.0-204.5 mbsf) did not achieve a full stroke. The cores were oriented starting with 3H. Downhole temperature measurements were taken with the APC temperature (APCT) tool as listed in Table T1. Most of the cores were odoriferous (H2S) and were stored on the catwalk rack after splitting to degas, which reduced the smell of H2S in the laboratory stack. Headspace measurements on the cores yielded trace amounts of methane (<100 ppm) and ethane (<3 ppm). No higher hydrocarbon compounds were detected. The nonmagnetic core barrel was deployed on even-numbered cores (Table T1). The APC cored 204.5 m and recovered 211.7 m (recovery = 103.5%).
The hole was deepened with the extended core barrel (XCB) from 204.5 to 430.6 mbsf, where refusal was encountered when the last core (Core 46X) required 105 min to advance 7.7 m in a chert and chalk sequence. The XCB cored 226.1 m and recovered 198.1 m (87.6% of the interval). The total recovery for the hole was 409.8 m (recovery = 95.2%) (Table T1).
The hole was flushed with 30 bbl of sepiolite mud and then displaced with 200 bbl of 8.9-lb/gal sepiolite mud in preparation for logging. The bit was placed at the logging depth of 99.4 mbsf, and logging began at 0100 hr on 8 May. The triple combination (triple combo) tool string with the Lamont-Doherty Earth Observatory (LDEO) Multi-Sensor Spectral Gamma Ray Tool (MGT) on top was deployed first and then followed by the Formation MicroScanner (FMS)-sonic tool string. One pass with the triple combo was conducted from total depth (429 mbsf) to the mudline, followed by one full pass from 430 mbsf to the bit and one repeat pass from 167 mbsf to the seafloor with the LDEO MGT. The two subsequent passes with the FMS-sonic tool string also reached the bottom of the hole. Hole conditions were unusually smooth, and the hole diameter ranged in size from 11.5 to 14.5 in (29-37 cm). The General Purpose Inclinometer Tool (GPIT) accelerometer logs showed increasing deviation from vertical in the hole below 170 mbsf, reaching 6.5° at the base.
All tools gave excellent results because of the good hole conditions. Logging was completed by 1945 hr on 8 May, and the bit was pulled free of the seafloor at 1940 hr on 8 May.
The vessel was offset 10 m east of Hole 1238A. Prior to coring, a bottom water temperature measurement was obtained with the APCT tool with the bit positioned just above the seafloor. All temperature measurements combined at this site indicated a high thermal gradient of ~12.7°C/100 m. To obtain the desired stratigraphic overlap with the first hole, the bit was then situated at 2212.0 mbrf, and Hole 1238B was initiated with the APC at 2103 hr. The core barrel was full and, consequently, the seafloor depth from the previous hole was applied to this hole (2213.5 mbrf). Piston coring deepened the hole to 201.0 mbsf. The interval 46.0-49.0 mbsf was drilled to optimize recovery of cores by offsetting with those recovered in Hole 1238A. A total of 198.0 m was cored and 209.5 m was recovered (recovery = 105.8%) (Table T1). The core barrels containing Cores 9H, 14H, 15H, and 17H through 21H were drilled over (see also Table T3 in the "Leg 202 Summary" chapter). The nonmagnetic core barrel was deployed on odd-numbered cores (Table T1). The nonmagnetic core barrel was not used after this to prevent possible damage to hardware as a consequence of the drilling-over process. The cores were oriented starting with Core 3H. The bit was pulled free of the seafloor at 1605 hr on 9 May.
The vessel was moved 10 m east, and Hole 1238C initiated with the APC at 1647 hr on 9 May. The bit was positioned at a depth of 2206 mbrf. The seafloor depth calculated from the recovery of the mudline core was 2214.5 mbrf. Piston coring deepened the hole to 162.5 mbsf to ensure the recovery of a complete stratigraphic section. Two intervals were drilled without coring to maintain the proper overlap with data from the previous two holes (39.0-42.0 and 108-110.5 mbsf). Cores were oriented starting with Core 4H. The nonmagnetic core barrel was deployed on even-numbered cores up to Core 14H. Three stuck core barrels had to be drilled over (Cores 15H, 17H, and 18H). The cored interval was 162.5 m, with 167.9 m recovered (recovery = 103.3%) (Table T1).
The vessel was secured for the transit and left location at 1200 hr on 10 May.