Ice Core Interplanetary Dust Helium Isotope Data: Readme file
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World Data Center for Paleoclimatology, Boulder
and
NOAA Paleoclimatology Program
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NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!!
NAME OF DATA SET: Ice Core Interplanetary Dust Helium Isotope Data
LAST UPDATE: 11/2001 (Original Receipt by WDC Paleo).
CONTRIBUTOR: Ed Brook, Washington State University.
IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2001-077
SUGGESTED DATA CITATION: Brook, E.J., et al., 2001,
Ice Core Interplanetary Dust Helium Isotope Data,
IGBP PAGES/World Data Center for Paleoclimatology
Data Contribution Series #2001-077.
NOAA/NGDC Paleoclimatology Program, Boulder CO, USA.
ORIGINAL REFERENCE:
Brook, E.J., Kurz, M.D., Curtice, J., and Cowburn, S., 2000,
Accretion of Interplantary Dust in Polar Ice,
Geophysical Research Letters, Vol. 27, No. 19, p. 3145 (2000GL011813)
GEOGRAPHIC REGION: Global
PERIOD OF RECORD: 0-97 KYrBP
FUNDING SOURCES: National Science Foundation (USA),
National Aeronautical and Space Administration (USA).
LIST OF FILES: Readme_helium.txt (this file),
helium.doc (Microsoft Word format).
helium.txt (Tab-delimited ASCII format).
DESCRIPTION: Ice Core Interplanetary Dust Helium Isotope Data
Helium isotope data from Ice Cores at GISP2 (Greenland) and
Vostok (Antarctica) as a proxy for extraterrestrial dust flux.
Table 1. Helium Isotope Data for > 0.45 Micron Particles Filtered From Ice Samples.
Sample Depth (m) Age *1 (ka) Wgt. Ice (g) 4He (10-12 cm3 g-1 ice) 3He/4He (R/Ra) 3He (10-18 cm3 g-1 ice) Ice Accum.*2 (g cm-2 a-1) 3He Flux (10-12cm3 cm-2 ka-1)
GISP2 (Greenland)
132.7-133.1 0.4 1092.7 0.77 ± 0.02 42.83 ± 0.28 45.47 ± 0.96 22.4 1.02 ± 0.02
133.6-133.7 0.41 338.5 0.99 ± 0.02 8.75 ± 0.25 12.01 ± 0.42 22.4 0.27 ± 0.01
134.2-134.3 0.41 800.6 4.26 ± 0.09 7.31 ± 0.06 43.09 ± 0.93 22.4 0.97 ± 0.02
137.2-137.7a *5 0.43 751.75 0.59 ± 0.01 15.70 ± 0.25 12.73 ± 0.32 22.4 0.29 ± 0.01
137.2-137.7b *5 0.43 938.88 0.82 ± 0.02 28.58 ± 0.28 32.55 ± 0.73 22.4 0.73 ± 0.02
137.54-138.18 0.42 1186.23 0.86 ± 0.02 16.17 ± 0.18 19.15 ± 0.50 22.4 0.43 ± 0.01
137.54-138.18 *3 0.42 1186.23 0.30 ± 0.01 0.96 ± 0.19 0.39 ± 0.08
Mean ± 2sigma: 0.62 ± 0.27
Vostok (Antarctica) *4
110.0-110.19a *5 3.8 259.69 1.82 ± 0.04 173.51 ± 0.92 437.02 ± 9.04 2 0.87 ± 0.02
110.0-110.19b *5 3.8 280.35 2.22 ± 0.04 174.11 ± 0.78 535.39 ± 10.97 2 1.07 ± 0.02
110.19-110.38 3.8 265.96 1.33 ± 0.03 139.07 ± 1.14 255.16 ± 5.51 2 0.51 ± 0.01
110.38-110.48a *5 3.8 145.15 1.01 ± 0.02 159.05 ± 1.72 223.08 ± 5.07 2 0.45 ± 0.01
110.38-110.48b *5 3.8 139.5 2.22 ± 0.04 152.21 ± 1.05 466.61 ± 9.87 2 0.93 ± 0.02
Mean ± 2sigma: 0.77±0.25
1096 75.26 154.73 5.16 ± 0.01 109.98 ± 0.56 785.88 ± 16.22 1.2 0.97 ± 0.02
1145 77.99 168.92 3.15 ± 0.06 143.79 ± 0.80 626.62 ± 13.02 1.5 0.92± 0.02
1220 84.04 152.03 2.37 ± 0.05 156.14 ± 1.04 510.77 ± 10.73 1.5 0.75 ± 0.02
1261 87.56 158.99 3.60 ± 0.07 116.14 ± 0.71 578.09 ± 12.10 1.4 0.80 ± 0.02
1265 87.89 215.93 2.39 ± 0.05 90.85 ± 0.60 300.99 ± 6.34 1.3 0.40 ± 0.01
1285 89.14 254.01 3.00 ± 0.06 159.23 ± 0.67 660.49 ± 13.50 1.4 0.91 ± 0.02
1303.3 89.94 176.94 2.85 ± 0.06 128.74 ± 0.88 508.51 ± 10.75 1.5 0.76 ± 0.02
1307.0a *5 90.08 67.44 46.34 ± 0.93 200.05 ± 0.86 12829.29 ± 262.45 1.4 17.88 ± 0.37
1307.0b *5 90.08 100.98 1.60 ± 0.03 102.38 ± 0.98 227.18 ± 5.04 1.4 0.32 ± 0.01
1307.0c *5 90.08 94.16 37.28 ± 0.75 193.13 ± 0.92 9963.83 ± 204.85 1.4 13.89 ± 0.29
1316.6a *5 90.87 105.46 1.44 ± 0.03 163.28 ± 1.69 325.71 ± 7.33 1.6 0.52 ± 0.01
1316.6b *5 90.87 106.24 1.44 ± 0.03 173.75 ± 1.77 346.75 ± 7.78 1.6 0.55 ± 0.01
1321 91.28 271.7 2.22 ± 0.04 147.82 ± 0.74 453.21 ± 9.34 1.4 0.65 ± 0.01
1333 92.39 221.45 2.26 ± 0.05 136.33 ± 0.76 426.69 ± 8.86 1.4 0.62 ± 0.01
1341 92.99 119.85 8.17 ± 0.16 149.61 ± 0.72 691.59 ± 34.79 1.5 2.47 ± 0.05
1346 93.36 207.5 5.60 ± 0.11 194.93 ± 0.77 1512.07 ± 30.83 1.5 2.21 ± 0.05
1403.6 97.3 106.56 5.80 ± 0.12 101.04 ± 0.65 811.55 ± 17.04 1.6 1.27 ± 0.03
*1 Ages for GISP2 from Meese et al. [1997]; ages from Vostok from SPECMAP time scale of Sowers et al [1993].
*2 GISP2: Cuffey and Clow [1997]; Vostok: Sowers et al. (1993).
*3 0.2-0.45 m size fraction.
*4 Depths for below 111.0 m are top depths of samples spanning 10-15 cm.
*5 Replicates for Holocene GISP2 and Vostok samples were prepared by cutting core sections longitudinally.
Replicates of deep Vostok samples were made on unoriented variable sized pieces
from 10-15 cm intervals.