# Juan de Fuca Ridge Mass Flux Data over the Last 500 ka #----------------------------------------------------------------------- # World Data Center for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # NOTE: Please cite original publication, online resource and date accessed when using this data. # If there is no publication information, please cite Investigator, title, online resource and date accessed. # # Description/Documentation lines begin with # # Data lines have no # # # Online_Resource: https://www.ncdc.noaa.gov/paleo/study/21009 # Online_Resource: http://www1.ncdc.noaa.gov/pub/data/paleo/paleocean/by_contributor/costa2017/costa2017-35pc.txt # # Archive: Paleoceanography # # Parameter_Keywords: lithology, radiogenic isotope #--------------------------------------- # Contribution_Date # Date: 2016-12-01 #--------------------------------------- # Title # Study_Name: Juan de Fuca Ridge Mass Flux Data over the Last 500 ka #--------------------------------------- # Investigators # Investigators: Costa, K.M.; McManus, J.F. #--------------------------------------- # Description and Notes # Description: #--------------------------------------- # Publication # Authors: Costa, K.M. and J.F. McManus # Published_Date_or_Year: 2017 # Published_Title: Efficacy of 230Th normalization in sediments from the Juan de Fuca Ridge, northeast Pacific Ocean # Journal_Name: Geochimica et Cosmochimica Acta # Volume: 197 # Edition: # Issue: # Pages: 215-225 # Report Number: # DOI: 10.1016/j.gca.2016.10.034 # Online_Resource: # Full_Citation: # Abstract: 230Th normalization is an indispensable method for reconstructing sedimentation rates and mass fluxes over time, but the validity of this approach has generated considerable debate in the paleoceanographic community. 230Th systematics have been challenged with regards to grain size bias, sediment composition (CaCO3), water column advection, and other processes. In this study, we investigate the consequences of these effects on 230Th normalization from a suite of six cores on the Juan de Fuca Ridge. The proximity of these cores (<30 km) suggests that they should receive the same particle rain rate of sediment, but the steep bathymetry of the ridge leads to substantial sediment redistribution and variable carbonate preservation, both of which may limit the usage of 230Th in this region. Despite anticipated complications, 230Th normalization effectively recon- structs nearly identical particle rain rates from all six cores, which are summarily unrelated to the total sedimentation rates as calculated from the age models. Instead the total sedimentation rates are controlled almost entirely by sediment focusing and winnowing, which are highly variable even over the short spatial scales investigated in this study. Furthermore, no feed- backs on 230Th systematics were detected as a consequence of sediment focusing, coarse fraction variability, or calcium car- bonate content, supporting the robustness of the 230Th normalization technique. #--------------------------------------- # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: AGS-1338832 #--------------------------------------- # Site Information # Site_Name: AT26-19 35PC # Location: North Pacific Ocean # Country: # Northernmost_Latitude: 44.99118 # Southernmost_Latitude: 44.99118 # Easternmost_Longitude: -130.45737 # Westernmost_Longitude: -130.45737 # Elevation: -2731 #--------------------------------------- # Data_Collection # Collection_Name: AT26-19 35PC Costa17 # First_Year: 6594 # Last_Year: 309737 # Time_Unit: cal yr BP # Core_Length: # Notes: #--------------------------------------- # Chronology_Information # Chronology: #--------------------------------------- # Variables # Data variables follow that are preceded by "##" in columns one and two. # Variables list, one per line, shortname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data) ## depth_cm depth,,,cm,,,,,N ## age_calyrBP age,,,cal yrs before present,,,,,N ## massflux Total mass flux,,,g cm-2 ka-1,,paleoceanography,,,N ## massflux_err_2s Total mass flux,,Two sigma error,g cm-2 ka-1,,paleoceanography,,,N #------------------------ # Data # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Value: NaN depth_cm age_calyrBP massflux massflux_err_2s 0.5 6594 0.473 0.007 4.5 8877 0.460 0.007 8.5 11160 0.546 0.009 12.5 13443 0.660 0.010 16.5 15726 0.621 0.010 20.5 18009 1.214 0.021 24.5 20292 1.289 0.024 28.5 22575 1.398 0.026 32.5 24857 1.093 0.021 36.5 27140 1.007 0.019 40.5 29423 0.756 0.014 44.5 31706 0.961 0.018 48.5 33989 0.923 0.018 52.5 36272 0.843 0.016 56.5 38555 0.878 0.017 60.5 40838 0.874 0.017 64.5 43121 0.875 0.018 68.5 45404 0.950 0.019 72.5 47687 1.015 0.022 76.5 49970 0.981 0.022 80.5 52253 0.901 0.020 84.5 54536 0.942 0.021 88.5 56819 0.926 0.021 92.5 59102 0.915 0.021 96.5 61385 0.902 0.021 100.5 63667 0.853 0.021 104.5 65950 0.869 0.022 108.5 68233 0.917 0.024 112.5 70516 0.841 0.023 116.5 72799 0.811 0.022 120.5 75082 0.852 0.026 124.5 77365 0.629 0.019 128.5 79648 0.569 0.017 132.5 81931 0.537 0.016 136.5 84214 0.565 0.018 140.5 86497 0.434 0.014 144.5 88780 0.413 0.013 148.5 91063 0.392 0.013 152.5 92609 0.412 0.013 156.5 93638 0.393 0.013 160.5 94668 0.469 0.016 164.5 95697 0.464 0.016 168.5 96726 0.479 0.016 172.5 97755 0.435 0.015 176.5 98784 0.422 0.014 180.5 99813 0.388 0.013 184.5 100843 0.404 0.014 188.5 101872 0.370 0.012 192.5 102901 0.366 0.012 196.5 103930 0.352 0.012 200.5 104959 0.383 0.013 204.5 105988 0.385 0.014 208.5 107018 0.381 0.013 212.5 108047 0.372 0.013 216.5 109076 0.360 0.013 220.5 110105 0.330 0.012 224.5 111134 0.363 0.013 228.5 112163 0.343 0.012 232.5 113193 0.356 0.012 236.5 114222 0.336 0.012 240.5 115251 0.533 0.020 244.5 116280 0.552 0.020 248.5 117309 0.522 0.019 252.5 118338 0.435 0.016 256.5 119368 0.402 0.014 260.5 120397 0.381 0.013 264.5 121426 0.362 0.012 268.5 122455 0.350 0.012 272.5 123484 0.358 0.012 275.7 124308 0.373 0.012 279.7 125337 0.437 0.014 283.7 126366 0.447 0.015 287.7 127395 0.452 0.016 291.7 128424 0.466 0.016 295.7 129453 0.453 0.015 299.7 130483 0.450 0.016 303.7 132462 1.143 0.052 307.7 135619 1.276 0.059 311.7 138776 1.378 0.066 315.7 141932 1.255 0.059 319.7 145089 1.188 0.056 323.7 148245 1.173 0.055 327.7 151402 1.076 0.051 331.7 154559 1.066 0.052 335.7 157715 1.012 0.050 339.7 160872 1.003 0.052 343.7 164028 0.989 0.055 347.7 167185 1.049 0.061 351.7 169667 1.017 0.061 355.7 171236 1.074 0.064 359.7 172805 0.914 0.054 363.7 174375 0.919 0.055 367.7 175944 0.823 0.050 371.7 177513 0.808 0.049 375.7 179082 0.743 0.046 379.7 180652 0.640 0.039 383.7 182221 0.687 0.043 387.7 183790 0.530 0.034 391.7 185359 0.766 0.047 395.7 186928 0.558 0.037 399.7 188498 0.533 0.036 403.7 190067 0.520 0.035 407.7 191636 0.497 0.035 411.7 193205 0.437 0.031 415.7 194775 0.443 0.031 419.7 196344 0.419 0.029 423.7 197913 0.407 0.027 427.3 199325 0.399 0.027 431.3 200895 0.462 0.034 435.3 202464 0.490 0.039 439.3 204033 0.504 0.040 443.3 205602 0.474 0.037 447.3 207172 0.552 0.047 451.3 208741 0.468 0.034 455.3 210310 0.508 0.044 459.3 211879 0.427 0.034 463.3 213448 0.425 0.037 467.3 215018 0.429 0.039 471.3 216587 0.472 0.048 475.3 218156 0.532 0.058 479.3 219725 0.622 0.075 483.3 222475 0.594 0.069 487.3 225475 0.616 0.076 491.3 228475 0.605 0.070 495.3 231475 0.667 0.085 499.3 234475 0.620 0.065 503.3 235660 0.607 0.059 507.3 236460 0.593 0.061 511.3 237260 0.579 0.056 515.3 238060 0.566 0.053 519.3 238860 0.558 0.054 523.3 239660 0.518 0.050 525.3 240634 0.603 0.060 527.3 244864 0.556 0.057 529.3 249011 0.509 0.047 531.3 251722 1.666 0.241 533.3 253914 1.779 0.260 535.3 256105 1.451 0.202 537.3 258296 1.773 0.271 539.3 260488 1.715 0.268 541.3 262679 1.896 0.316 543.3 264870 1.888 0.372 545.3 267062 1.738 0.333 547.3 269253 1.569 0.278 549.5 271664 1.225 0.230 553.5 272212 1.272 0.241 565.5 272212 3.759 2.510 589.5 272212 1.051 0.294 593.5 272212 0.378 0.050 597.5 274419 0.664 0.131 601.5 277951 0.466 0.059 605.5 281483 0.611 0.091 609.5 285014 0.715 0.128 613.5 288546 0.679 0.117 617.5 292078 0.685 0.126 621.5 295610 0.759 0.139 625.5 299142 1.107 0.265 629.5 302674 0.841 0.171 633.5 306205 0.743 0.147 637.5 309737 0.675 0.130