|
Core, section,
interval (cm) |
Layer
thickness (cm) |
Depth (mbsf)
|
Lithology (approximate percent)
|
Description, structure, and contact
|
||
|---|---|---|---|---|---|---|
|
Biogenic
|
Glass – Pumice
+ 1 |
Roundness (Qz)
|
||||
| Miocene | ||||||
| 201-1227A- | ||||||
| 13H-2, 146–147.6* | 1.3 | 115.07 | NA | (98–99)–NA | NA | Buff silt to very fine sand, top gradational, bottom may be erosional |
| Pliocene | ||||||
| 201-1228A- | ||||||
| 8H-2, 83.5–84 | 0.5 | 64.24 | 1 | 1–3 | 1–2 | Light gray fine silt-clay, 3%–5% dolomite, thins in center, poorly sorted, top gradational; bottom broken |
| 8H-3, 114–117* | 3.0 | 66.04 | 1–2 | 1–30 |
|
Light silt, ~5% dolomite, clay pod in base, moderate-well sorted, top: right convex |
| 9H-1, 69.8–72* | 2.2 | 72.09 | 1 | 50–NA | NA | Cream clay, ~45% groundmass, few dark coarse crystals, convex to left contacts, one flaser mark |
| 9H-1, 72–73 | 1.0 | 72.12 |
 1 |
(0.5–2)–75 | 1–2 | Brown silt, ~1% dolomite, pumice: round, bottom: gradational, both slightly wavy |
| 9H-1, 74.5–77* | 2.5 | 72.15 | 1–2 | 1.5–5 | 1–2 | Light gray silt, ~4% dolomite, ~20% coated grains, top: gradational wavy, bottom: slightly inclined |
| 9H-1, 81.5–83 | 1.5 | 72.22 | 1–3 | 1.5–20 | 3–5 | Brown silt (angular), ~3%–5% round pumice, top: sharp to gradational, bottom: gradational-inclined |
| 9H-1, 97–101.6* | 4.6 | 72.37 | NA | (1–2)–(3–5) | NA | Gray-tan silt, ~80% glass-coated grains + 2, normally graded, top gradational |
| 9H-1, 121.4–124* | 2.6 | 72.61 | 1 | 1.5–(15–30) |
|
Gray-tan silt, ~5% round pumice, ~2%–3% dolomite, normal grading, 60% pumice and ~15% dolomite in bottom half |
| 11H-2, 32.5–37.5* | 25.5 | 91.73 | NA | 1–(30–40) | <0.5 | Gray-tan-black coarse silt-sand, ~1%–2% round pumice, thins to right, ~1.8 cm, bottom: slightly inclined |
| 11H-2, 50.2–52.3* | 2.1 | 91.90 | NA | 80–(3–5) | 1–2 | Black-brown clay, ~3%–5% round pumice, finely laminated, top: convex, bottom: slight incline, both gradational |
| 11H-2, 52.3–55 | 2.7 | 91.93 | NA | 75–(1–3) | 1–2 | Tan-cream fine silt, ~2% round pumice and 55% groundmass, finely laminated, gradational-slightly inclined |
| 11H-2, 55–56.6* | 1.6 | 91.95 | 1–3 | 30–10 | 1 | Gray-brown-gray silt with ~20% groundmass, normal grading, slightly inclined, top: gradational |
| 11H-2, 59–60.6* | 1.6 | 91.99 | <1 | 70–10 | NA | Cream silt, poor–moderately sorted, sharp top: slight ripple, bottom: planar (possible correlation with Section 201-1227A-13H-2) |
| 14H-2, 8.1–11.7* | 3.6 | 111.98 | 3 | (1–2)–(20–30) | <1–1 | Tan-brown-gray coarse silt; distinctly more coarse than layers above and below |
| 14H-2, 116.5–117.5† | 1.0 | 113.06 | 10 | <1–20 | 1 | Gray-tan-brown silt to sand, ~1% round pumice, thins slightly (1–2 mm), gradational, bottom: slightly scoured (1–2 mm) |
| 14H-2, 129.3–130.2 | 0.9 | 123.19 | 3–5 | NA–20 | 1–2 | Orange silt (gray ~2 mm below surface); ~30% groundmass, bottom: slightly wavy |
| 14H-2, 144–149† | 5.0 | 113.34 | 5–10 | 0.5–60 | NA | Tannish gray silt; ~3%–5% ooids; thinly laminated; top: planar, bottom: end of core |
| 14H-5, 52.8–59* | 6.2 | 116.93 |
5 |
(1–3)–(30–50) | 1 | Gray-tan silt; ~20% coated; top: partly scoured (filled with laminations), bottom: slight break, top concave, bottom slightly wavy |
| 14H-5, 96.5–100 | 3.5 | 117.37 | 1–2 | 1–80 | 1 | Cream-light gray silt, bottom tan (10%–15% biogenic), top: broken, wavy, bottom: slightly wavy |
| 14H-5, 117.4–121.6* | 4.2 | 117.57 | 1–3 | 1–(30–40) | <1 | Gray-tan (orangish) silt, ~1 mm laminae at top |
| 14H-5, 132.5–133.5 | 1.0 | 117.72 | 1–3 | 0.5–60 | NA | Cream-tan silt, thins to the left, top: sharp, wavy, bottom: planar, broken |
| 14H-6, 17.3–23*† | 5.7 | 118.07 | 5–10 | 1–80 | 1–2 | Brown silt, ~50% biogenic in bottom centimeter, top: concave, bottom: slightly wavy |
| 14H-6, 23.5–26.5† | 3.0 | 118.14 |
1–5 5–10 |
(1–15)80 |
1 | Gray-tan silt, sharp, top: slightly wavy, bottom: concave, pumice and biogenic increase in the bottom centimeters |
| 16H-1, 36.5–43* | 6.5 | 128.77 | 2–3 | (2–3)–(15–25) |
0.5 |
Gray silt, ~20% groundmass (~5% at bottom), top: slightly rippled |
| 16H-1, 44–48* | 4.0 | 128.84 | 1 | 2.5–20 | <1 | Gray silt, planar, bottom: gradational |
| 16H-1, 60–64* | 4.0 | 129.00 |
1 |
1.5–(20–30) | <1 | Gray silt, gradational planar contacts |
| 16H-1, 64.5–67* | 2.5 | 129.05 |
3 |
2.5–50 |
1 |
Gray silt, top: wavy, bottom: planar |
| 16H-1, 92–96 | 4.0 | 129.32 | 1–2 | 1.5–60 | <1 | Gray silt, top: planar, bottom: wavy |
| 16H-1, 110.8–112 | 1.2 | 129.51 | 1–2 | 0.5–70 | <1 | Gray silt, light tan-light cream laminae |
| 16H-1, 114–117.5 | 3.5 | 129.54 | 1–2 | 2.5–70 | <1 | Gray-light cream interlaminae, finely laminated, top and bottom: convex up |
| 16H-1, 118.5–123* | 4.5 | 129.59 | 1–2 | 2–70 | <1 | Gray silt, few discontinuous laminae |
| 16H-1, 132–133 | 1.0 | 129.72 | 1–2 | 2–20 |
1 |
Gray silt, ~70% coated grains, top: planar, bottom: end of core |
| 16H-2,12.5–16* | 3.5 | 130.03 | 1–2 | (1–1.5)–80 | NA | Gray silt, tan, finely laminated, gradational convex up to the right |
| 16H-2, 27.5–34* | 6.5 | 130.18 | 1 | 2.5–(60–70) | <–0.5 | Gray silt, one tan lamination (~1 mm) in center |
| 16H-2, 118.5–124* | 5.5 | 131.09 | 1–2 | 2–(60–70) |
0.5 |
Gray silt, tan, finely laminated, ~3%–5% ooids |
| 16H-3, 96–98.5* | 2.5 | 132.35 | 1 | 0.5–(940–50) | NA | Tan silt, one brown lamination, ~5% ooids, top: sharp, bottom: gradational slightly wavy |
| 16H-3, 110.5–114* | 3.5 | 132.51 | 1–2 | 1–60 | 1–2 | Tan finely laminated silt, bottom: gradational, both: slightly wavy |
| 16H-3, 118–121.5* | 3.5 | 132.58 | 1–2 | 1–15 | <1 | Tan silt, ~15% round pumice, top: convex up, bottom: rippled |
| 16H-4, 27–40.5* | 13.5 | 133.17 | NA | 1–30 | 1 | Gray silt, ~15% round pumice, top: gradational, both: planar |
| 16H-4, 40.5–42.5*† | 2.0 | 133.31 | 20 | 5–30 |
1 |
Gray-tan finely laminated silt, biogenic ostracodes |
| 18H-1, 48–56.5* | 8.5 | 147.88 | 1–3 | 2–60 |
0.5 |
Gray silt, gray-tan up to 51 cm (gradational), ~1% round pumice, ~5%–10% groundmass |
| 18H-1, 62–67* | 5.0 | 148.02 | 1–2 | 2–(70–80) |
0.5 |
Gray silt, ~2%–3% round pumice, top: inclined, bottom: planar |
| 18H-2, 5.8–9.5* | 3.7 | 148.96 | 1–2 | 2–70 |
0.5 |
Gray-tan finely laminated silt, ~1% round pumice, top: convex at right side |
| 18H-2, 50.5–57.5* | 7.0 | 149.41 | 3 | 2–70 | <0.5 | Tan-brown silt, top half slightly laminated (54.5-gradational) lower half laminated, ~1% round pumice |
| 18H-2, 79.7–89.2* | 3.2 | 149.70 | 1–3 | 2–70 | <0.5 | Tan-brown finely laminated silt, ~1% round pumice, top: wavy, bottom: convex to right |
| 18H-2, 88–90* | 2.0 | 149.78 | 1–2 | 2–70 | <0.5 | Cream silt, ~1% round pumice, vesicular glass present, convex bed |
| 18H-2, 112–115* | 3.0 | 150.02 | 1–2 | 2–90 | <0.5 | Tan silt, ~3%–5% round pumice, top: slightly convex to right, bottom: end of core |
| 18H-3, 95.5–97* | 1.5 | 151.36 | 1–3 | (1–1.5)–80 | 1–2 | Gray-tan silt; ~1%–2% round pumice |
| 18H-4, 0–3* | 3.0 | 151.95 | 1–2 | 2–70 | <0.5 | Tan-gray silt, ~1% round pumice, some bioturbation, bottom: gradational planar |
| 18H-4, 38–42* | 4.0 | 152.28 | 1–2 | 2–70 | <0.5 | Tan silt, ~1% round pumice, top: wavy, bottom: planar |
| 18H-4, 49–55* | 6.0 | 152.35 | 1–3 | 2–70 | <0.5 | Tan and cream silt, ~1% round pumice, brown pod at top |
| 18H-4, 83.5–88* | 4.5 | 152.74 | 1–2 | 2–70 | <0.5 | Tan silt, ~1%–2% round pumice, top: slightly wavy, sharp, bottom: sharp planar and slightly bioturbated |
| Pleistocene | ||||||
| 201-1229A- | ||||||
| 1H-2, 99.6–99.9 | 0.3 | 2.50 |
3 |
2–3 | NA | Gray silty crystal-pumice-hash, discontinuous, inclined lamina, top: gradational |
| 3H-3, 50–50.5*† | 0.5 | 17.90 | 10–15 | 75–NA | NA | Gray-white clay lamina, planar, top: gradational |
| 5H-5, 126–129* | 3.0 | 40.66 | 1–2 | 3–NA | 1 | White-cream silt, fines upward, slightly inclined and gradational contacts |
| 6H-3, 18.7–20*† | 1.3 | 43.09 | 5–10 | 2–5 | NA | Gray-tan clay, slightly inclined, thins to one end |
| 8H-3, 107–109* | 1.8 | 69.97 | 0.5 | <1–10 | 2–3 | Gray silt, ~10%–25% dolomite, fines upward, inclined, top: gradational |
| 8H-3, 108.8–109* | 0.2 | 69.99 |
5 |
3–NA | 1–2 | Cream, crystal hash, very fine silt lamina, inclined |
| 10H-5, 37–44* | 7.0 | 85.77 | 3–5 | (1–3)–NA | 2–3 | Gray clay, ~3%–5% dolomite, fines upward |
| 11H-3, 2–6.5† | 4.5 | 91.92 | 5–10 |
1 |
10–15 | Gray-tan silt, ~3%–5% dolomite, fines upward |
| 11H-3, 6.5–9.2* | 2.7 | 91.97 | 1–3 | (1–2)–10 | 1–2 | Gray-tan silt, ~1%–3% dolomite, coated grains account for a majority of round grains |
| 11H-3, 10.2 | TL | 92.00 | 1–3 | (0.5–1)–NA | <1 | Light-colored discontinuous silt lamina, ~20%–30% coated grains |
| 11H-3, 39.3–39.6† | 0.3 | 92.29 | 5–10 | (1–2)–(5) | NA | Light-colored discontinuous silt lamina, ~3%–5% dolomite, bottom: gradational |
| 11H-3, 49.5–50.5† | 1.0 | 92.80 | 10–15 | (2–3)–NA | NA | Light gray silt between gray clay beds, dolomite ~5%, 5%–10% opaques, normal grading |
| 14H-1, 88.3–88.5† | 0.2 | 118.28 | 1–3 | <1–NA | NA | Cream silt, ~10%–15% dolomite, pinches out |
| 14H-4, 139.2† | TL | 123.29 | 5–10 | <1–(10–15) | NA | Gray-tan-brown silty sand, slightly inclined |
| 14H-5, 50–56*† | 6.0 | 123.90 | 3–5 | (2–3)– |
1 |
Cream-gray-black silt, fines upward, ~10%–20% dolomite |
| 18H-1, 0–3* | 3.0 | 155.40 | 3–5 | (1–2)–(15–20) | NA | Gray-tan silt, ~1%–2% dolomite |
| 18H-1, 25–74† | 49.0 | 155.65 | 5–10 | (1–2)–(50–60) | NA | Gray-tan silt, two tan laminae-biogenic, fine-planar-laminae, bottom: inclined |
| 18H-2, 115–115.5* | 0.5 | 158.07 | 1–3 | (1–2)–NA | NA | Gray-white-orange sandy silt lamina |
| 18H-2, 117.2–117.4* | 0.2 | 158.07 | 3–5 | 1–10 | NA | Gray-white sandy silt lamina, bottom: gradational |
| 18H-2, 117.4–127* | 9.6 | 156.17 | 3–5 | (1–2)–(10–15) | NA | Gray-tan silt, ~1%–2% dolomite, top: gradational |
| 18H-3, 48–56*† | 8.0 | 159.88 | 5–10 | (1–2)–NA | NA | Gray-white poorly sorted feldspar-quartz silty sand within reworked bed, planar |
| 18H-3, 114.5–122*† | 7.5 | 159.55 | 10–15 | 1–(5–10) | NA | Gray-tan sandy silt, bottom: break |
| 14H-5, 32–43.5 | 11.0 | 123.73 | 3–5 | Too fine to tell | NA | Cream clay, ~5%–10%–15% dolomite, crystal-rich pods of dolomite, slightly concave contacts |
| 14H-4, 18.5–23 | 4.5 | 122.08 |
10 |
(1–3)–NA | NA | Gray-cream clay, groundmass is first-order gray and white, discontinuous laminae and pod |
Notes: Unless otherwise specified contacts between layers are planar and sharp. * = whole-rock geochemistry was acquired for these layers. † = layer is borderline primary (10%–15% biogenic material or dolomite). NA = not applicable; the feature was not observed. Glass–Pumice +1 percent = glass-coated grains, unless specified otherwise in the description. +2 = glass-coated grains are primarily round, ~20% of these are round pumice.