Construction of the composite and spliced section from Holes 1133B and 1133C followed the methods outlined in "Composite Depths" in the "Explanatory Notes" chapter. Table T3 (also in ASCII format) relates mbsf depth to meters composite depth (mcd) for each core and section at Holes 1133B and 1133C and provides offset values for the conversion of mbsf depths to mcd. The composite section indicates full recovery to a depth of 42 mcd.
The primary lithologic parameters used to create the composite section were the 400-nm color reflectance data, a ratio of the 700- to 400-nm color reflectance data measured on split cores, and gamma-ray attenuation (GRA) density data measured on whole-round cores (Fig. F10). For specifics regarding data collection procedures and parameters, see "Physical Properties". Biostratigraphic and paleomagnetic datums were not used in the construction of the composite section because of the shallow total depth of coring and the disturbance of the record caused by slumping.
The composite section for Site 1133 is presented in Figure F10. The primary difficulty encountered in the construction of this composite section was the presence of a slumped interval from 19.9 to 27 mcd in both holes and poor recovery below 38 mbsf resulting from the presence of multiple chert beds.
The sediments comprising the composite section range from Holo-cene to middle Miocene age, based upon biostratigraphic data (see "Biostratigraphy"). The stratigraphic record within the range of the composite section is divided into three primary lithostratigraphic units. The upper unit, lithostratigraphic Unit I, is further divided into two subunits. Subunit IA (0-6 mbsf) is defined by the presence of thinly interbedded unlithified calcareous ooze mudstones and wackestones, which exhibit distinctive but low-amplitude features in the color reflectance and density data that are easily correlated between holes. Litho-stratigraphic Subunit IB (6-21 mbsf) consists of thicker beds (4-6 m) of calcareous ooze mudstone and wackestone, which are easily correlated on the basis of distinctive, high-amplitude, 2- to 5-m-thick oscillations in the color reflectance and GRA density records (Fig. F10).
A slumped calcareous ooze unit occurs near the base of lithostratigraphic Unit 1 from ~19.9 to 26.5 mcd. The top of the slumped interval was picked and correlated between holes using the occurrence of multiple very short wavelength (<0.5 m), high-amplitude excursions in the color reflectance data (Fig. F10) that correspond to distorted, alternating bands of light and dark color in the slumped sediments. The base of the slump was correlated between holes at a prominent transition to a plateau in high reflectance values and low 700:400 nm and GRA density values. These data characteristics correspond to lithostratigraphic Unit II, a calcareous ooze of early Pliocene-late Miocene age. The base of lithostratigraphic Unit II was correlated between holes at a prominent decrease in reflectance values and an increase in density values at 32 mcd. This transition corresponds to a major unconformable surface separating lithostratigraphic Unit II from darker bioclastic wackestones of lithostratigraphic Unit III (middle Miocene).
The composite and spliced sections indicate that recovery was complete to 42 mcd. (Figs. F10, F11; Table T4, also in ASCII format). Minimal recovery in cores below 42 mcd prohibited further composite section construction.