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doi:10.2204/iodp.proc.320321.209.2013

Results and discussion

For each site, in addition to the offset, splice, and stretch tie point tables, we have provided in the “Appendix” all of the cleaned GRA, MS, natural gamma radiation (NGR), and color reflectance data along with CSF, CCSF, and adjusted CCSF depths, where applicable.

Site U1336 consisted of only two holes. An effective splice carries to a depth of ~152 m CCSF, where there is a poorly recovered interval. Below this depth there are primarily appends rather than ties between cores. Offsets and splice points are provided in Tables T1 and T2.

Site U1337 is more complex, with four holes and a much greater total depth than Site U1336. Below 220 m CCSF, a confused section of ~50 m CCSF was characterized by incomplete recovery in all holes. A short gap may persist at 220 m CCSF, although we chose tie points. Core 321-U1337C-9H has been appended to the bottom of Core 321-U1337C-8H, suggesting another short break in recovery. At 267 m CCSF there is a definite break caused by poor recovery of a hard chert layer. Comparison of GRA records with downhole density logs (Malinverno, 2013) indicates that most of the section is represented in the cored material. Between 267 and 440 m CCSF continuous correlation can be made, although the amplitudes of the variations in properties are such that there may be some incorrect tie points. A major gap occurs at 444 m CCSF where Core 321-U1337A-44X is appended to Core 321-U1337A-43X. Particularly puzzling is the large gap seen in Holes U1337C and U1337D at the same level. This “void” is the result of forcing the color change at ~451 m CCSF to the same level in all holes. It may be that this color change occurs higher in the section in the latter two holes than in Hole U1337A. This question is not resolvable using data available. Offsets and splice points are provided in Tables T3 and T4.

At Site U1338, features between all records are well aligned to ~280 m CCSF. Ship heave of several meters during coring in Hole U1338C resulted in relatively more core disturbance in the softer sediments recovered from that hole, and the splice was subsequently made primarily from Holes U1338A and U1338B in the upper 260 m CCSF (to Core 321-U1338A-27H). The remainder of the splice alternated between Holes U1338B and U1338C.

At the base of Core 321-U1338C-28H, overlap was lost because of poor recovery in corresponding cores from Holes U1338A and U1338B. Another gap occurred at the base of Core 321-U1338C-31H, where a chert interval was encountered. Several other ties were made on the basis of short overlaps between 280 and 360 m CCSF. Ties below 360 m CCSF were generally good to 430 m CCSF, whereupon poor core condition and low variability in the data used for correlation left little to do but finish out the splice with the lower four cores from Hole U1338C. Offsets and splice points are provided in Tables T5 and T6.

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