Oxygen isotopes -- snowpits; GISP2 Site 31 REFERENCES: Bolzan, J.F., and M. Strobel. 1994. Accumulation-rate variations around Summit, Greenland. Journal of Glaciology 40:56-66. DATA DESCRIPTION: These files contain oxygen-isotope profiles for 9 shallow cores (to approximately 17 m depth) recovered over a 150 x 150 km survey grid in central Greenland. All cores were recovered in May, 1987. Isotopic data in the upper 2 m of each profile were from the shallow drilling pits. Details on the site location, the core recovery, and the assignment of core loss are given in Bolzan and Strobel, (1994). For the data below, all depths are in cm. Dating of samples was based on the seasonal variation in the oxygen isotope stratigraphy, along with measurements of gross beta activity (see Bolzan and Strobel, 1994). Time is in decimal years, where 87 = 1987, etc. The first 2 columns refer to the true depth and age at the top of the sample, where the age is based on a spline interpolation of the dating described in Bolzan and Strobel (1994). The time is in decimal calendar years. Column 3 is density in kg/m3. Column 4 are the O18 values in per mil. Column 5 is the ice-equivalent depths at the top of the sample. SITE 31: N 72 20 55, W 40 12 50, 3115 m DATA: Depth Top Cal. Year Density del18O Ice depth (cm) Top kg/m^3 (per mil) (cm) 0 1987.64 310.28 -34.23 0 10 1987.52 347 -38.48 3.38 20 1987.34 347 -36.94 7.16 30 1987.12 366.28 -41.62 10.94 40 1986.88 355.27 -40.48 14.93 50 1986.66 286.42 -30.56 18.8 60 1986.5 290.09 -29.89 21.92 70 1986.38 313.96 -32.19 25.08 80 1986.28 315.79 -30.37 28.5 90 1986.2 367.2 -34.29 31.94 100 1986.12 387.4 -38.03 35.94 110 1986.05 397.49 -36.22 40.16 120 1985.95 406.67 -37.67 44.49 130 1985.83 412.18 -35.08 48.92 140 1985.69 386.48 -33.58 53.41 150 1985.55 328.64 -29.05 57.62 160 1985.45 354.35 -33.39 61.2 170 1985.34 369.95 -34.79 65.06 180 1985.22 400.25 -34.32 69.09 190 1985.08 421.36 -37.45 73.45 200 1984.91 372.71 -30.81 78.04 205 1984.83 372.71 -29.75 80.07 210 1984.74 374.54 -29.34 82.1 215 1984.65 389.23 -28.12 84.14 220 1984.55 390.57 -27.45 86.26 225.5 1984.45 387.4 -31.15 88.6 230.5 1984.35 385.56 -34.96 90.71 235.5 1984.25 383.72 -37.3 92.81 240.5 1984.16 385.56 -38.7 94.9 245.5 1984.08 385.56 -41.51 97 250.5 1984 385.56 -41.99 99.1 255.5 1983.93 385.56 -38.64 101.2 260.5 1983.87 380.05 -35.21 103.3 265.5 1983.81 380.05 -36 105.37 270.5 1983.76 380.05 -35.86 107.44 275.5 1983.71 389.23 -33.57 109.51 280.5 1983.65 409.43 -33.28 111.63 285.5 1983.6 411.26 -32.91 113.86 290.5 1983.53 407.59 -31.93 116.1 295.5 1983.46 396.58 -32.41 118.32 300.5 1983.39 398.41 -35.29 120.48 305.5 1983.31 396.58 -38.94 122.65 310.5 1983.23 396.58 -40.95 124.81 315.5 1983.14 414.93 -42.57 126.97 320.5 1983.05 416.77 -44.04 129.23 325.5 1982.95 414.93 -42.99 131.5 330.5 1982.86 416.77 -37.66 133.76 335.5 1982.76 416.77 -32.66 136.03 340.5 1982.66 387.4 -31.23 138.3 345.5 1982.55 389.23 -31.03 140.41 350.5 1982.44 387.4 -30.85 142.53 355.5 1982.33 394.74 -33.64 144.64 360.5 1982.21 396.58 -35.42 146.79 365.5 1982.1 396.58 -37.66 148.95 370.5 1982 396.58 -37.81 151.11 375.5 1981.92 369.04 -36.57 153.27 380.5 1981.85 340.68 -36.34 155.28 385 1981.72 438.8 -34.59 160.5 390 1981.67 436.97 -33.99 162.89 395 1981.61 436.97 -31.37 165.27 400 1981.54 435.63 -29.58 167.65 405.5 1981.45 407.59 -30.43 170.26 410.5 1981.36 411.27 -32.48 172.48 415.5 1981.25 428.96 -38.06 174.72 421 1981.12 431.46 -40.81 177.29 426 1981 429.62 -41.09 179.64 431 1980.88 429.63 -39.01 181.98 436 1980.76 430.62 -36.77 184.32 441.5 1980.63 429.63 -33.87 186.9 446.5 1980.54 427.79 -29.28 189.24 451.5 1980.47 425.95 -29.5 191.57 456.5 1980.34 415.6 -32.22 198.57 462 1980.31 414.94 -35.38 201.06 467 1980.28 416.77 -37.25 203.32 472 1980.25 414.94 -38.6 205.59 477 1980.2 416.77 -38.87 207.85 482 1980.14 415.6 -38.98 210.12 487.5 1980.05 435.13 -39.63 212.61 492.5 1979.94 435.13 -37.82 214.98 497.5 1979.8 433.3 -35.02 217.35 502.5 1979.65 435.13 -33.7 219.71 507.5 1979.5 436.97 -33.85 222.08 512.5 1979.36 440.64 -35.07 224.46 517.5 1979.23 440.64 -36.89 226.86 522.5 1979.11 436.97 -39.51 229.26 527.5 1979 436.97 -40.75 231.64 532.5 1978.9 436.97 -41.12 234.02 537.5 1978.82 438.8 -39.1 236.4 542.5 1978.74 436.97 -36.7 238.79 547.5 1978.67 436.97 -32.86 241.17 552.5 1978.6 440.64 -30.23 243.55 557.5 1978.53 449.82 -28.43 245.95 562.5 1978.47 446.15 -29.1 248.4 567.5 1978.4 438.8 -32.22 250.83 572.5 1978.33 436.97 -34.48 253.22 577.5 1978.26 438.8 -37.19 255.6 582.5 1978.13 470.02 -38.36 259.86 587.5 1978.04 471.85 -39.57 262.42 592.5 1977.96 470.02 -38.06 264.99 597.5 1977.86 470.02 -34.74 267.55 602.5 1977.77 471.85 -31.21 270.11 607.5 1977.68 469.2 -28.32 272.68 612 1977.61 451.65 -28.04 274.98 617 1977.53 446.15 -27.94 277.44 622 1977.47 446.15 -27.52 279.87 627 1977.42 447.98 -27.59 282.3 632 1977.37 446.15 -28.59 284.74 637 1977.32 446.15 -30.85 287.17 642 1977.27 449.82 -34.05 289.6 647 1977.21 481.04 -36.53 292.05 652 1977.14 481.03 -38.22 294.67 657 1977.05 479.19 -38.38 297.29 662 1976.94 481.03 -37.85 299.9 667 1976.82 481.04 -34.67 302.52 672 1976.68 481.03 -31.04 305.14 677 1976.56 479.19 -30.05 307.76 682 1976.45 492.05 -30.63 310.37 687 1976.35 492.05 -30.72 313.05 692 1976.28 490.21 -30.71 315.73 697 1976.21 492.05 -31.99 318.4 702 1976.15 490.21 -34.65 321.08 707 1976.09 488.38 -37.78 323.75 712 1976.03 471.85 -39.23 326.41 717 1975.96 473.69 -38.08 328.98 722 1975.89 473.69 -35.95 331.56 727 1975.81 473.69 -33.71 334.14 732 1975.72 471.85 -30.98 336.72 737 1975.63 473.69 -29.41 339.29 742 1975.54 473.69 -29.18 341.87 747 1975.46 473.69 -29.36 344.45 752 1975.38 475.52 -30.25 347.03 757 1975.3 473.69 -31.99 349.62 762 1975.23 475.52 -33.85 352.2 767 1975.16 475.52 -35.54 354.79 772 1975.1 473.69 -37.8 357.38 777 1975.03 475.52 -39.95 359.96 782 1974.95 497.56 -37.81 363.21 787 1974.88 497.55 -36.98 365.92 792 1974.81 497.55 -34.83 368.63 797 1974.73 497.55 -33.74 371.34 802 1974.65 497.56 -31.35 374.05 807 1974.55 497.55 -30.63 376.76 812 1974.44 490.21 -31.55 379.47 817 1974.32 481.03 -34.36 382.14 822 1974.2 479.19 -36.64 384.76 827 1974.07 479.2 -37.43 387.37 832 1973.93 481.03 -36.82 389.98 837 1973.8 479.19 -35.03 392.6 842 1973.67 481.03 -32.39 395.21 847 1973.55 486.54 -32.3 397.83 852 1973.45 492.05 -33.01 400.48 857 1973.37 493.88 -33.78 403.16 862 1973.3 492.05 -33.65 405.85 867 1973.23 493.88 -33.47 408.53 872 1973.16 492.05 -34.35 411.22 877 1973.08 491.64 -35.57 413.9 881.5 1973 519.59 -35.38 416.31 886.5 1972.89 517.75 -34.26 419.14 891.5 1972.77 517.75 -32.34 421.96 896.5 1972.65 501.23 -31.04 424.78 901.5 1972.54 475.52 -30.48 427.51 906.5 1972.46 475.52 -31.48 430.1 911.5 1972.4 473.69 -33.58 432.69 916.5 1972.35 475.52 -36.97 435.27 921.5 1972.31 475.53 -38.64 437.86 926.5 1972.26 492.05 -40.36 440.45 931.5 1972.2 495.72 -40.14 443.13 936.5 1972.12 495.72 -37.64 445.83 941.5 1972 495.72 -35.25 448.53 946.5 1971.85 493.88 -31.28 451.23 951.5 1971.68 497.55 -28.81 453.92 956.5 1971.5 504.9 -29.13 456.63 961.5 1971.34 503.06 -31.68 459.38 966.5 1971.19 504.9 -34.77 462.12 971.5 1971.06 503.06 -36.49 464.87 976.5 1970.95 517.75 -36.09 467.61 981.5 1970.84 539.78 -35.99 470.43 986.5 1970.76 517.75 -35.74 473.37 991.5 1970.68 504.9 -34.89 476.19 996.5 1970.62 504.9 -32.6 478.94 1001.5 1970.57 503.06 -30.43 481.69 1006.5 1970.52 504.9 -29.71 484.43 1011.5 1970.48 495.72 -31.3 487.18 1016.5 1970.44 486.54 -32.8 489.88 1021.5 1970.39 484.71 -33.81 492.53 1026.5 1970.34 484.7 -33.75 495.17 1031.5 1970.27 501.23 -33.44 497.81 1036.5 1970.19 530.6 -33.94 500.54 1041.5 1970.07 528.77 -34.73 503.43 1046.5 1969.92 514.08 -33.71 506.31 1051.5 1969.75 508.58 -32.99 509.11 1056.5 1969.58 506.74 -32.38 511.88 1061.5 1969.42 506.74 -32.7 514.64 1066.5 1969.28 506.73 -33.37 517.4 1071.5 1969.16 508.58 -33.9 520.16 1076.5 1969.05 510.41 -33.68 522.93 1081.5 1968.95 510.4 -33.89 525.71 1086.5 1968.86 510.41 -33.11 528.49 1091.5 1968.77 510.4 -31.83 531.27 1096.5 1968.69 510.41 -30.45 534.05 1101.5 1968.61 512.24 -29.6 536.83 1106.5 1968.54 510.41 -29.31 539.62 1111.5 1968.47 510.4 -29.93 542.4 1116.5 1968.4 512.24 -31.61 545.18 1121.5 1968.33 521.43 -33.78 547.97 1126.5 1968.25 521.43 -35.4 550.81 1131.5 1968.16 521.42 -36.29 553.65 1136.5 1968.06 543.46 -36.85 556.49 1141.5 1967.94 547.12 -35.8 559.45 1146.5 1967.79 547.12 -34.56 562.43 1151.5 1967.64 547.14 -33.68 565.41 1156.5 1967.5 541.62 -33.57 568.39 1161.5 1967.37 497.55 -34.22 571.34 1166.5 1967.26 503.06 -35.43 574.05 1171.5 1967.15 552.64 -37.52 576.79 1176.5 1967.05 552.64 -38.7 579.8 1181.5 1966.95 537.95 -38.27 582.81 1186.5 1966.87 537.95 -37.52 585.74 1191.5 1966.78 537.95 -36.05 588.67 1196.5 1966.7 537.96 -33.96 591.6 1201.5 1966.61 537.95 -32.23 594.53 1206.5 1966.5 534.1 -32 597.46 1212 1966.37 493.88 -33.39 600.66 1217 1966.25 493.88 -35.37 603.35 1222 1966.13 493.88 -36.28 606.04 1227 1966 508.58 -36.29 608.73 1232 1965.87 515.92 -34.6 611.5 1237 1965.74 517.75 -32.49 614.31 1242 1965.61 517.75 -30.75 617.13 1247 1965.5 517.75 -30.69 619.95 1252 1965.4 515.92 -31.51 622.77 1257 1965.31 503.06 -32.61 625.58 1262 1965.24 484.71 -33.05 628.32 1267 1965.17 486.53 -34.34 630.96 1272 1965.1 532.44 -34.47 633.61 1277 1965.04 543.45 -35.28 636.51 1282 1964.96 543.46 -33.65 639.47 1287 1964.89 545.3 -32.79 642.43 1292 1964.81 543.45 -32.37 645.4 1297 1964.73 561.82 -31.65 648.36 1302 1964.65 560.82 -30.29 651.42 1307.5 1964.55 562.48 -29.78 654.78 1313 1964.45 565.48 -30.63 658.15 1318 1964.36 567.33 -32.01 661.23 1323 1964.26 565.49 -33.75 664.32 1328 1964.16 567.32 -34.63 667.4 1333 1964.05 565.49 -34.79 670.49 1338 1963.95 567.32 -34.55 673.57 1343 1963.83 543.46 -34.3 676.66 1348 1963.73 545.3 -33.53 679.62 1353 1963.63 545.29 -31.48 682.59 1358 1963.54 543.46 -30.57 685.56 1363 1963.46 545.29 -31.52 688.52 1368 1963.4 561.82 -32.63 691.49 1373 1963.34 591.2 -33.8 694.55 1378 1963.27 589.35 -34.16 697.77 1383 1963.2 589.36 -34.16 700.98 1388 1963.11 543.46 -34.38 704.19 1393 1963 545.29 -34.3 707.15 1398 1962.87 543.46 -33.24 710.12 1403 1962.72 545.29 -32.01 713.08 1408 1962.57 543.46 -31.24 716.05 1413 1962.43 545.29 -32.2 719.01 1418 1962.3 543.46 -34.16 721.98 1423 1962.17 556.3 -35.55 724.94 1428 1962.06 556.31 -36.63 727.97 1433 1961.95 556.31 -36.01 731 1438 1961.84 578.34 -34.14 734.03 1444 1961.72 576.81 -31.16 737.81 1450 1961.6 548.96 -30.81 741.58 1455 1961.5 547.12 -30.97 744.57 1460 1961.4 548.96 -30.67 747.55 1465 1961.3 543.46 -31.76 750.54 1470 1961.2 541.62 -34.56 753.5 1475 1961.1 541.62 -36.41 756.45 1480 1961 543.45 -36.28 759.4 1485 1960.9 545.3 -35.41 762.36 1490 1960.79 552.64 -33.53 765.33 1495 1960.68 550.8 -32.02 768.34 1500 1960.56 552.63 -31.2 771.34 1505 1960.44 550.8 -32.07 774.35 1510 1960.31 552.64 -33.56 777.35 1515 1960.18 558.15 -35.06 780.36 1520 1960.06 563.64 -35.81 783.4 1525 1959.95 561.83 -35.39 786.47 1530 1959.85 563.64 -34.06 789.53 1535 1959.76 562.48 -32.33 792.6 1540.5 1959.66 561.83 -30.56 795.97 1545.5 1959.58 563.64 -29.83 799.03 1550.5 1959.5 559.99 -29.47 802.1 1555.5 1959.41 558.14 -31.16 805.15 1560.5 1959.32 558.14 -33.71 808.19 1565.5 1959.23 558.15 -36.03 811.23 1570.5 1959.14 558.14 -37.28 814.27 1575.5 1959.05 558.14 -37.55 817.31 1580.5 1958.96 558.97 -37.18 820.35 1585 1958.88 534.27 -36.05 823.09 1590 1958.79 525.09 -34.01 826 1595 1958.62 525.09 -32.6 832.34 1600 1958.54 523.26 -31.32 835.2 1605 1958.46 525.09 -32.41 838.05 1610 1958.38 523.27 -34.21 840.91 1615 1958.3 525.09 -37 843.76 1620 1958.21 523.26 -39.04 846.62 1625 1958.13 525.1 -40.07 849.47 1630 1958.04 523.26 -40.65 852.33 1635 1957.96 525.09 -39.34 855.18 1640 1957.87 523.27 -37.9 858.04 1645 1957.79 477.36 -36.18 860.89