Results of analyses are presented in Tables T1 and T2 and Figures F2, F3, F4, F5, F6, and F7. Data for all parameters are highly variable at the meter-scale, but exhibit subtle upcore patterns at both sites.
Mean grain sizes range from 2.2 ø (220 µm; fine sand) to 8.03 ø (3.9 µm; clay) at Site 1130, and 0.2 ø (890 µm; coarse sand) to 7.9 ø (4.2 µm; very fine silt) at Site 1132. Both sites exhibit a coarsening-upward sequence (Figs. F2, F3). Site 1130 sediments are dominantly silt and clay size below 50 mbsf and sand size above 50 mbsf (Fig. F2). Site 1132 sediments are dominantly silt size below 150 mbsf and sand and silt size above 150 mbsf to the base of the bryozoan-rich units at 65 mbsf (Fig. F3). Except for the bryozoan-rich units above 65 mbsf at Site 1132, gravel-size sediments are rarely present at either site.
Carbonate content ranges from 86.6 to 99.2 wt% at Site 1130 and 79.2 to 99.1 wt% at Site 1132 (Tables T1, T2). Values are consistently >90 wt% for both sites but tend to be slightly higher at Site 1130. Both sites exhibit a subtle upcore increase in carbonate content (Figs. F2, F3).
Results of XRD analyses are expressed as the relative percentages of aragonite, HMC, LMC, and dolomite. Site 1130 contains 11.5%-28.6% aragonite, 4.4%-68% HMC, 14.9%-79.3% LMC, and 0%-4.4% dolomite (Table T1). Site 1132 contains 0%-37.1% aragonite, 0%-73.5% HMC, 0.1%-100% LMC, and 0%-14.2% dolomite (Table T2). Both sites exhibit upcore increases in HMC and accompanying decreases in LMC (Figs. F2, F3). Aragonite exhibits a more subtle upcore increase that is most pronounced at Site 1132 (Fig. F3). Dolomite is always subordinate, only present consistently below 65 mbsf at Site 1132 (Fig. F3). Dolomite is rarely present at Site 1130 (Fig. F2).
Samples from decimeter-scale intervals also show highly variable values for all parameters but exhibit distinct characteristics for each of the two different lithologies making up one complete cycle. Figures F4, F5, F6, and F7 show the decimeter-scale data for sediment texture, carbonate content, and carbonate mineralogy for each of the four intervals sampled. All four intervals show a consistent pattern of aragonite- and/or HMC-rich, very fine sand and coarse silt, alternating with LMC-rich, fine to medium silt. The former corresponds to olive-gray units observed on board ship, and the latter corresponds to the light gray units observed on board ship. The combination of the two make up one complete lithologic cycle (see "Core Descriptions" contents list in Feary, Hine, Malone, et al., 2000).
Site 1130, 77.50-79.95 mbsf (Fig. F4), contains a 40-cm-thick interval between 78.40 and 78.80 mbsf that consists of silt- and clay-sized sediment reaching up to 50% LMC. This grades both above and below into silt- and sand-sized sediments consisting dominantly of HMC, which reaches up to 45% of the sediment. The 40-cm-thick interval between 78.40 and 78.80 mbsf corresponds to light gray units, whereas the units above and below correspond to olive-gray units. Contacts between units are gradational over ~40-cm intervals (see "Site 1130 Core Descriptions" in Feary, Hine, Malone, et al., 2000).
Site 1130, 114.60-117.20 mbsf (Fig. F5), consists of an HMC- and LMC-rich, medium-coarse silt overlying an HMC- and LMC-rich silt and sand, separated by a gradational contact at ~115.4 to 115.8 mbsf. The top fine-grained layer corresponds to light gray units, whereas the bottom coarse-grained layer corresponds to olive-gray units (see "Site 1130 Core Descriptions" in Feary, Hine, Malone, et al., 2000). HMC and LMC each make up 30%-60% of the sediment in both layers, making this the only decimeter-scale sampling interval that shows no evidence of fractionation in carbonate mineralogy between the two lithologies.
Site 1132, 66.90 to 69.70 mbsf (Fig. F6), is characterized by silt and sand containing roughly equal amounts of aragonite, HMC, and LMC overlying an LMC-rich silt. The top layer corresponds to olive-gray units, and the bottom layer corresponds to light gray units. The contact between the two layers is sharp and well defined at 67.70 mbsf (see "Site 1132 Core Descriptions" in Feary, Hine, Malone, et al., 2000).
Site 1132, 151.00-154.90 mbsf (Fig. F7), consists of sand and silt with 43%-49% LMC overlying an LMC-dominant silt. The upper layer consists of roughly equal amounts of sand and silt with little clay, consistently >5% dolomite, and corresponds to olive-gray units. The lower layer consists almost entirely of fine-coarse silt, consistently >70% LMC, and <2% dolomite and corresponds to light gray units. This is the only decimeter-scale interval where dolomite is consistently found. The contact between the two layers is sharp and well defined at 151.40 mbsf. The basal part of the interval from 154.30 to 154.90 mbsf represents a transition back into an olive-gray unit lying below (see "Site 1132 Core Descriptions" in Feary, Hine, Malone, et al., 2000).