At Site 1086, two holes were cored with the APC corer to a maximum depth of 206 mbsf. Measurements of magnetic susceptibility and GRAPE density were made on the MST, and color reflectance was measured with the Minolta spectrophotometer. All parameters were measured at 10-cm resolution. Graphic and quantitative alignment of stratigraphic features of the MST and color reflectance data were used to depth adjust adjacent cores to establish a meters composite depth (mcd) scale. Beginning from the core top, a constant was added to the mbsf scale to establish depth offsets for each core to assemble a single continuous composite section. For Site 1086, continuity of the composite section was demonstrated to 232 mcd, covering the entire depth cored.
Magnetic susceptibility, GRAPE, and color reflectance (lightness L*) data were all used to construct a composite section and to verify core gaps. Total reflectance was the primary parameter used to constrain intercore depth adjustments; however, all parameters were useful in establishing continuity. A 31-cm Gaussian filter was used to smooth all parameters in the composite section.
The composite depth section shows excellent agreement between Holes 1086A and 1086B (Fig. 13). Depth offsets for individual cores relative to their mbsf position are given in Table 7. Intracore stretching and compression often lead to feature mismatches of the data, which are indicative of core distortion and cannot be resolved with a single depth adjustment per core. Splices at 47 and 216 mcd are based upon limited overlap; however, the offsets are consistent with core expansion, suggesting that if gaps exist, they are relatively small (<1 m). The composite section over these intervals should be regarded with caution.
Upon completion of the composite depth sections, a single spliced record was assembled using overlapping cores from Holes 1086A and 1086B for magnetic susceptibility and lightness (L*; Fig. 14). Hole 1086A served as the backbone of the sampling splice. The splice for Site 1086 (Table 8) can be used as a sampling guide. Core expansion relative to the mbsf scale is ~10% (Fig. 15).