Grain Size and Magnetic Fabric Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!! NAME OF DATA SET: Grain Size and Magnetic Fabric Data LAST UPDATE: 4/2003 (Original Receipt by WDC Paleo) CONTRIBUTOR: Dr. Leah Joseph, University of Michigan (now at Hobart and William Smith Colleges) IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2003-023 SUGGESTED DATA CITATION: Joseph, L., et al., 2003, Grain Size and Magnetic Fabric Data, IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2003-023. NOAA/NGDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Joseph, L., Rea, D.K., van der Pluijm, B.A., 1998, Use of grain size and magnetic fabric analyses to distinguish among depositional environments, Paleoceanography, Vol 13, No. 5, Pages 491-501. GEOGRAPHIC REGION: Delgada deep-sea fan (northern California margin), Blake Outer Ridge (western North Atlantic), and Bermuda Rise. PERIOD OF RECORD: various DESCRIPTION: Grain Size and Magnetic Fabric Data interpreted in terms of depositional environment and paleocurrent strength. ABSTRACT: The combined use of grain size and magnetic fabric analyses provides the ability to discriminate among depositional environments in deep-sea terrigenous sediments. We analyzed samples from three different depositional settings: turbidites, pelagic or hemipelagic interlayers, and sediment drifts. Results indicate that sediment samples from these different environments can be distinguished from each other on the basis of their median grain size, sorting, as well as the intensity and shape of magnetic fabric as determined from an examination of the anisotropy of magnetic susceptibility. We use these discriminators to interpret downcore samples from the Bermuda Rise sediment drift. We find that the finer grains of the Bermuda Rise (relative to the Blake Outer Ridge) do not result from lower depositional energy (current speed) and so may reflect a difference in the nature of sediment being delivered to the site (i.e. distance from source) between the two locations. DATA: Table A. Results of Inter-depositional environment analysis. Size, I.G.S.D., P', T and bulk susceptibility are the average of all runs per sample. Grain size analyses were run at least three times while anisotropy of magnetic susceptibility analyses were repeated at least five times. The bulk susceptibily values in parentheses are the bulk susceptibilities at around 77 K. These samples were also imparted with ARM. ‡ Samples imparted with pARM Core W8209B-19GC 39°16.4'N 127°22.8W 4355m depth: Volume- Corrected Interval Size, IGSD, Bulk Suscept. Sedimentary cm micron micron P' T (x 10-6 SI) Environment 56-58 6.80 (8.98) 0.91 (8.53) 1.05 0.66 240 turbidite 61-63‡ 5.74 (18.8) 0.94 (13.6) 1.08 0.85 416 (582) turbidite 67-69‡ 6.80 (8.96) 0.81 (8.55) 1.06 0.53 341 (487) turbidite 72-74‡ 6.48 (11.2) 0.91 (10.1) 1.12 0.55 646 (692) turbidite 81-83 7.19 (6.84) 0.91 (7.78) 1 0.3 362 interlayer 112-114 7.22 (6.71) 0.94 (8.35) 1 0.19 267 interlayer 197-199‡ 7.18 (6.90) 0.94 (8.09) 1.01 0.25 308 (492) interlayer 204-206 7.00 (7.83) 1.01 (8.90) 1.01 0.47 345 interlayer 209-211‡ 6.44 (11.5) 1.15 (10.9) 1.01 0.05 303 (515) interlayer Core W8209B-20GC 39°35.7'N 127°11.3W 4294m depth: Volume- Corrected Interval Size, IGSD, Bulk Suscept. Sedimentary cm micron micron P' T (x 10-6 SI) Environment 78-80 6.11 (14.5) 1.01 (11.7) 1.11 0.31 651 turbidite 86-88 5.36 (24.3) 1.01 (15.8) 1.11 0.58 1182 turbidite 94-96‡ 5.08 (29.6) 1.01 (17.7) 1.13 0.58 1194 (1018) turbidite 107-109 7.20 (6.80) 0.89 (7.70) 1.01 -0.18 366 interlayer 116-118‡ 7.17 (6.95) 0.95 (7.95) 1 -0.24 353 (529) interlayer 133-135 7.21 (6.74) 0.89 (7.67) 1.01 -0.01 301 interlayer 161-163 7.24 (6.62) 0.91 (7.81) 1.01 -0.21 275 (496) interlayer 183-185‡ 7.16 (6.98) 0.94 (7.96) 1.01 0.09 258 (452) interlayer 257-259 7.17 (6.97) 0.95 (8.74) 1.01 -0.08 255 interlayer Core CH89-1P 31°15.0'N 74°50.0'W 3180m depth: Volume- Corrected Interval Size, IGSD, Bulk Suscept. Sedimentary cm micron micron P' T (x 10-6 SI) Environment 22-24 6.53 (10.8) 1.03 (10.1) 1.01 0.22 120 drift 42-44 6.64 (10.1) 1.03 (9.61) 1.01 0.52 110 drift 62-64 6.47 (11.3) 1.02 (10.3) 1.02 0.49 118 drift 82-84‡ 6.73 (9.41) 1.03 (9.69) 1.01 -0.28 137 (280) drift 102-104 6.70 (9.65) 1.05 (9.59) 1.07 -0.89 196 drift 122-124 6.81 (8.91) 1.07 (9.55) 1.05 0.37 218 (373) drift 142-144 6.70 (9.62) 1.07 (10.1) 1.05 0.84 216 drift 162-164 6.56 (10.6) 1.12 (10.9) 1.02 0.76 257 (454) drift 182-184 6.45 (11.4) 1.09 (11.4) 1.02 0.37 277 (439) drift 202-204 6.60 (10.3) 1.07 (10.7) 1.03 0.46 274 drift 222-224 6.56 (10.6) 1.11 (10.9) 1.03 0.75 249 (443) drift 242-244 6.45 (11.4) 1.13 (11.4) 1.02 0.14 286 drift 262-264 6.21 (13.5) 1.11 (12.2) 1.04 0.18 387 drift 282-284 6.37 (12.0) 1.01 (11.3) 1.03 0.53 390 drift Core W8709A-12PC 42°05.1'N 125°40.6W 2970m depth: Volume- Corrected Interval Size, IGSD, Bulk Suscept. Sedimentary cm micron micron P' T (x 10-6 SI) Environment 402-404 6.96 (8.02) 0.98 (9.02) 1.08 -0.78 776 flow-in 462-464 6.99 (7.88) 0.98 (9.42) 1.08 -0.74 618 flow-in Table B. Results of analysis of Bermuda Rise core CH89-9P. This is an example of a sediment drift taken from near core GPC-5. Size, I.G.S.D., P', T and bulk susceptibility are the average of all runs per sample. Grain size analyses were run at least three times while magnetic fabric analyses were repeated at least five times. The bulk susceptibility values in parentheses are the bulk susceptibilities of a halved cube at 298K and 77 K respectively. Volume Corrected Depth Size, IGSD, Bulk Suscept. cm (micron) (micron) P' T x 10-6 SI 49 6.88 (8.50) 0.86 (8.43) 1.05 0.04 285 151.5 7.13 (7.13) 0.89 (7.82) 1.04 0.33 260 186.5 6.89 (8.43) 0.94 (8.82) 1.02 0.31 132 (147-288) 211.5 7.19 (6.87) 0.93 (8.06) 1.02 0.23 162 251.5 7.23 (6.68) 0.88 (7.56) 1.04 0.06 122 351.5 6.81 (8.89) 0.96 (9.09) 1.03 -0.1 181 (213-423) 455.5 6.54 (10.8) 1.01 (9.88) 1.02 0.15 204 550.5 6.79 (9.03) 0.96 (8.99) 1.03 -0.1 213 585.5 6.58 (10.5) 0.98 (10.0) 1.02 0.02 167 653 6.67 (9.82) 0.90 (9.15) 1.05 0.27 261 698 7.34 (6.18) 0.81 (6.82) 1.04 0.56 250 756 6.91 (8.34) 0.90 (8.37) 1.05 0.56 249 831 6.89 (8.43) 0.94 (8.63) 1.04 0.53 228 863.5 6.95 (8.09) 0.90 (8.69) 1.03 0.63 232 908 6.98 (7.94) 0.87 (8.01) 1.03 -0.1 300 963 7.41 (5.89) 0.86 (8.24) 1.06 0.8 164 1098 7.38 (5.99) 0.85 (7.19) 1.04 0.62 180 1130.5 7.09 (7.35) 0.94 (8.28) 1.05 0.37 379 1194.5 6.82 (8.83) 0.88 (8.46) 1.07 0.63 427 (466-572) 1202 6.93 (8.20) 0.90 (8.36) 1.04 0.24 372 1212 6.81 (8.93) 0.91 (8.95) 1.12 0.28 325 (389-510) 1222 7.16 (6.99) 0.86 (7.50) 1.1 0.44 241 1234.5 7.12 (7.17) 0.93 (8.40) 1.05 0.8 355 1244.5 7.40 (5.93) 0.79 (6.73) 1.06 0.58 486 1254.5 7.20 (6.79) 0.97 (8.02) 1.1 0.48 288 1264.5 7.05 (7.53) 1.02 (8.90) 1.09 0.4 188 1274.5 7.20 (6.81) 0.94 (8.11) 1.09 0.5 172 1284.5 7.19 (6.85) 0.95 (8.10) 1.08 0.75 187 1294.5 7.00 (7.82) 0.95 (8.45) 1.08 0.3 213 1299.5 7.08 (7.37) 0.99 (8.73) 1.09 0.08 252 1307 6.75 (9.33) 1.01 (9.40) 1.1 0.18 317 1312 6.84 (8.73) 1.00 (9.20) 1.1 0.28 296 1322 6.70 (9.62) 1.00 (9.61) 1.09 0.78 320 1327 6.79 (9.07) 1.00 (9.32) 1.09 0.41 330 1332 6.65 (9.93) 1.04 (10.1) 1.08 0.54 337 1337 6.59 (10.4) 0.99 (9.83) 1.09 0.78 387 1347 6.81 (8.89) 0.90 (8.62) 1.04 0.72 491 1357 7.06 (7.51) 0.91 (8.07) 1.09 0.84 276 1367 7.15 (7.04) 0.88 (7.81) 1.06 0.75 302 1372 6.90 (8.40) 1.00 (8.93) 1.04 0.69 315 1379.5 6.95 (8.06) 0.92 (8.26) 1.07 0.56 289 1384.5 6.97 (7.96) 0.96 (8.72) 1.09 0.91 248 (269-433) 1392 7.17 (6.93) 0.96 (8.08) 1.08 0.71 176 1404.5 6.94 (8.15) 0.97 (8.57) 1.06 0.59 256 1414.5 7.06 (7.50) 0.97 (8.75) 1.04 0.73 291 1424.5 6.78 (9.13) 1.04 (9.57) 1.08 0.57 219 1434.5 7.16 (6.98) 0.96 (8.18) 1.06 0.62 177 1444.5 7.09 (7.34) 0.90 (7.84) 1.05 0.78 296 1457 7.16 (6.99) 0.88 (7.55) 1.03 0.09 332 1469.5 7.39 (5.97) 0.84 (6.79) 1.06 0.59 470 1479 7.22 (6.69) 0.92 (7.64) 1.1 0.77 161 1484 7.19 (6.84) 0.95 (8.26) 1.08 0.58 161 1486.5 7.26 (6.54) 0.88 (7.30) 1.09 0.88 166 1491.5 7.30 (6.34) 0.88 (7.40) 1.09 0.69 192 1501.5 7.11 (7.23) 0.95 (8.48) 1.07 0.6 210 1600.5 7.19 (6.87) 0.95 (8.09) 1.07 0.45 206 1679.5 7.19 (6.86) 0.94 (7.88) 1.05 0.06 180 1737 7.03 (7.63) 1.00 (8.39) 1.02 0.5 221 1803.5 6.93 (8.21) 1.00 (8.67) 1.03 0.36 231 1891.5 7.32 (6.24) 0.92 (7.55) 1.05 0.53 163 (187-383)