Iceland Shelf 12KYr Quartz and K-Feldspar IRD Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: Please cite original reference when using these data, plus the data file URL and date accessed. NAME OF DATA SET: Iceland Shelf 12KYr Quartz and K-Feldspar IRD Data LAST UPDATE: 12/2011 (Original receipt by WDC Paleo) CONTRIBUTORS: Andrews, J.T. IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2011-152 WDC PALEO CONTRIBUTION SERIES CITATION: Andrews, J.T. 2011. Iceland Shelf 12KYr Quartz and K-Feldspar IRD Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2011-152. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Andrews, J.T. 2009. Seeking a Holocene drift ice proxy: non-clay mineral variations from the SW to N-central Iceland shelf: trends, regime shifts, and periodicities. Journal of Quaternary Science, Vol. 24, Issue 7, pp. 664-676, October 2009. DOI: 10.1002/jqs.1257 ABSTRACT: Quantitative X-ray diffraction analysis of the < 2mm sediment fraction was carried out on 1257 samples (from the seafloor and 16 cores) from the Iceland shelf west of 18°W. All but one core (B997-347PC) were from transects along troughs on the NW to N-central shelf, an area that in modern and historic times has been affected by drift ice. The paper focuses on the non-clay mineralogy of the sediments (excluding calcite and volcanic glass). Quartz and potassium feldspars occupy similar positions in an R-mode Principal Component analysis, and oligoclase feldspar tracks quartz; these minerals are used as a proxy for ice-rafted detritus (IRD). Accordingly the sum of these largely foreign minerals (Q&K) (to Icelandic bedrock) is used as a proxy for drift ice. A stacked, equi-spaced 100-yr record is developed which shows both low frequency trends and higher frequency events. The detrended stacked record compares well with the flux of quartz (mg/cm2/yr) at MD99-2269 off N Iceland. The multi taper method (MTM) indicated that there are three significant frequencies at the 95% confidence level with periods of ~2500, 445, and 304 yr. Regime shift analysis pinpoints intervals when there was a statistically significant shifts in the average Q&K weight%, and identifies four IRD-rich events separated by intervals with lower inputs. There is some association between peaks of IRD input, less dense surface waters (from 18O data on planktonic foraminifera), and intervals of moraine building. GEOGRAPHIC REGION: North Atlantic, Iceland Shelf PERIOD OF RECORD: 12KYrBP - present FUNDING SOURCES: US National Science Foundation grants ATM-0502515 DATA FILE URLS: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/andrews2009b/andrews2009b.txt ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/andrews2009b/andrews2009b.xls DESCRIPTION: The data are derived from quantitative X-ray diffraction analysis of the < 2 mm sediments from a series of cores around Iceland, all west of 18°W. The bedrock of Iceland is essentially devoid of quartz and k-feldspars (Q and K) and these minerals are frequently used as an index for the occurrence of drift ice (sea ice or icebergs). The data for all the cores have been processed using Analyseries so that there is a wt% estimate every 100-yr between 0 and 12,000 cal yr BP. Table 1. Core Locations Longitude Latitude Water depth NW Iceland B997-315 -24.332 66.736 220 MD99-2264 -24.197 66.679 235 MD99-2263 -24.197 66.679 235 MD99-2266 -23.265 66.228 106 SW Iceland B997-347 -24.17 63.21 321 N Iceland B997-324 -21.15 66.527 282 B997-330 -21.08 65.867 165 B997-325 -20.996 66.573 345 B997-327 -20.863 66.64 373 MD99-2269 -20.863 66.641 365 B997-323 -20.227 66.846 397 B99-322 -19.775 66.938 357 B997-321 -18.98 66.891 480 B997-317 -18.865 66.587 494 B997-319 -18.851 66.442 422 B997-316 -18.79 66.746 658 B997-320 -18.5 66.335 388 JR51GC-35 -17.961 66.999 420 Table 2. Data on cores used in this study (See Fig. 2) Number Core Basal Top Number average/ NW Iceland dates length(m) date date samples yrs sample B997-315 # 5 2.49 12420 2760 92 105 MD99-2264 6 11.45* 11850 1155 104 103 MD99-2263 # 5 0.46 1865 -50 46 42 MD99-2266 26 37.6 10825 400 175 60 N Iceland B99-322 4 0.5 14600 980 9 B997-323 3 1 ~15000 650 22 B997-324 17 2.89 12300 150 107 114 B997-325 10 2.71 11610 -50 85 137 B997-327 5 3.29 4340 310 63 64 MD99-2269 32 25.3 11860 -50 413 29 B997-330 9 5.4 10970 -50 108 102 B997-321 8 2.9 6160 355 62 94 B997-316 3 2.81 1335 -50 53 26 B997-317 6 1.74 3930 -50 32 124 B997-319 13 2.27 8950 175 69 127 B997-320 6 3.27 3400 -50 59 58 *Holocene length # Unpubl. dates DATA: Andrews 2009 Iceland Shelf Quartz and K-feldspar data Quartz and K-feldspar wt% data from quantitative X-ray diffraction analysis, 100-yr intervals CalYrBP B997-347 MD99-2264 B997-330 B997-324 MD99-2266 MD99-2263 B997-315 B997-317 B997-319 B997-316 B997-321 B997-320 B997-325 MeanQ+K SD #cores MD99-2269(qtz) QJR51-GC35 0 3.6 9.5 17.7 15.1 11.5 6.3 4 100 5.9 8.8 16.4 21.5 26.3 15.8 8.5 5 3.5 200 7.2 13.4 7.3 7.7 16.4 16.7 17.9 10.1 12.1 4.6 8 4.3 3.9 300 9.4 14.8 3.2 6.9 13.7 14.2 18.1 8.6 11.1 4.9 8 4.3 3.0 400 8.9 16.9 3.0 3.7 16.1 16.5 16.3 16.8 7.6 11.8 5.9 10 3.8 3.1 500 3.1 7.7 16.7 2.6 6.7 18.4 18.9 17.3 16.6 10.8 11.9 6.5 10 3.7 2.1 600 8.5 8.0 15.3 2.6 4.1 14.9 17.0 17.6 15.8 8.1 11.2 5.6 10 3.2 3.0 700 2.5 8.3 15.4 3.7 5.8 14.1 14.7 17.2 13.1 12.0 10.7 5.2 10 3.5 3.2 800 1.4 7.7 18.2 1.0 12.6 16.1 14.2 18.6 12.2 16.7 11.9 6.5 10 3.7 2.9 900 1.7 7.0 17.3 3.7 11.7 15.0 13.3 19.2 15.8 12.2 11.7 5.8 10 3.3 2.6 1000 2.0 6.4 15.9 3.3 17.1 11.2 13.8 16.3 17.3 8.6 11.2 5.8 10 2.7 2.3 1100 1.9 22.4 9.0 14.2 5.4 14.8 11.3 13.6 17.7 15.8 7.9 12.2 5.8 11 3.1 1.8 1200 2.9 17.3 3.8 14.8 4.6 6.7 14.2 15.7 9.2 9.6 9.9 5.3 10 2.8 1.7 1300 1.5 11.1 6.6 16.9 4.7 11.8 17.8 21.0 10.5 6.5 10.8 6.2 10 2.7 3.1 1400 1.6 6.7 5.1 14.3 4.8 16.2 19.1 16.9 16.6 10.5 11.2 6.2 10 3.2 2.8 1500 1.1 7.5 6.0 12.1 4.2 16.4 14.8 15.8 13.9 8.9 10.1 5.3 10 3.0 4.6 1600 1.0 4.4 8.4 10.2 3.2 18.0 13.0 12.4 11.2 12.3 9.4 5.2 10 3.0 3.1 1700 0.6 7.4 4.8 11.0 4.0 16.2 12.8 9.1 11.8 9.5 8.7 4.6 10 2.9 2.9 1800 1.6 5.4 3.0 13.6 3.5 14.0 13.8 16.0 9.2 8.9 5.6 9 3.0 2.5 1900 1.4 6.6 3.6 12.7 2.9 13.6 16.5 13.7 8.4 8.8 5.5 9 2.7 2.7 2000 2.1 7.9 4.3 11.4 2.0 12.0 17.2 10.9 8.9 16.5 9.3 5.4 10 2.6 2.5 2100 1.2 6.0 6.1 11.6 3.7 10.5 16.1 8.4 8.8 15.4 8.8 4.8 10 2.6 3.1 2200 1.2 4.4 7.5 12.2 4.5 15.5 13.8 9.1 12.1 14.4 9.5 4.9 10 3.1 2.9 2300 1.1 6.1 5.3 13.0 4.0 16.8 12.5 11.9 8.0 13.3 9.2 5.0 10 2.7 3.2 2400 1.2 6.5 7.4 14.0 5.0 14.7 15.8 14.1 8.3 14.8 10.2 5.1 10 2.9 2.7 2500 2.3 5.3 7.1 15.0 3.8 13.3 15.4 13.6 8.9 16.7 10.1 5.3 10 3.3 1.9 2600 1.7 8.0 6.0 15.4 3.4 2.3 11.6 16.8 14.9 9.8 16.1 9.6 5.7 11 2.7 2.1 2700 1.7 5.2 6.3 15.6 3.3 5.5 11.1 23.1 15.3 9.2 15.6 10.2 6.6 11 3.0 1.9 2800 2.7 6.4 4.8 13.5 2.1 8.7 11.3 13.1 13.7 9.0 15.4 9.2 4.7 11 2.6 2.7 2900 2.9 7.6 6.1 10.7 3.0 10.4 11.1 10.6 11.5 8.8 18.2 9.2 4.3 11 3.0 2.2 3000 3.3 11.0 5.2 10.4 3.8 11.3 12.6 11.3 10.9 9.9 17.2 9.7 4.1 11 2.7 2.3 3100 3.1 7.4 7.8 10.2 1.4 10.6 15.9 12.1 13.8 12.8 16.4 10.1 4.9 11 2.4 3.4 3200 2.2 8.1 7.7 10.1 3.2 7.6 14.8 13.0 11.0 10.4 22.9 10.1 5.7 11 2.9 2.9 3300 1.8 4.7 9.3 7.8 4.3 11.7 13.2 10.0 6.6 8.9 30.8 9.9 7.7 11 2.8 2.6 3400 2.1 10.3 6.5 7.0 1.2 13.1 12.5 8.5 4.2 6.6 35.1 9.7 9.2 11 2.6 2.7 3500 1.3 8.2 3.7 8.9 2.9 13.1 10.5 9.7 6.8 31.0 9.6 8.4 10 3.1 2.1 3600 1.0 5.3 4.2 10.1 3.7 14.2 12.1 9.0 26.5 9.6 7.7 9 2.9 2.0 3700 1.9 4.6 6.1 10.0 3.8 14.6 12.1 7.5 22.1 9.2 6.3 9 2.6 1.1 3800 2.1 6.4 5.7 8.8 1.7 13.5 13.3 6.8 17.2 8.4 5.3 9 2.5 1.3 3900 2.4 5.2 8.2 6.5 6.1 13.5 11.4 7.3 12.5 8.1 3.7 9 2.2 1.5 4000 2.3 5.5 10.9 9.5 3.8 13.9 10.9 8.4 13.4 8.7 4.1 9 1.9 1.5 4100 1.6 5.9 4.6 14.6 4.1 12.8 9.5 9.8 14.3 8.6 4.8 9 2.0 1.4 4200 1.0 4.4 5.7 16.2 3.0 12.6 8.3 9.9 16.6 8.6 5.6 9 2.2 1.9 4300 0.5 5.4 6.2 15.5 3.2 14.2 9.6 7.4 26.7 9.9 8.0 9 2.0 2.4 4400 0.1 4.3 7.5 13.5 2.7 13.9 11.5 4.8 24.0 9.1 7.4 9 1.9 1.5 4500 0.3 4.4 8.2 11.4 4.0 12.5 11.9 4.7 17.3 8.3 5.4 9 1.6 2.0 4600 0.7 4.5 4.2 10.4 5.0 11.4 9.6 8.8 10.2 7.2 3.7 9 1.6 2.3 4700 1.0 4.7 3.1 10.4 3.8 10.8 7.5 11.2 7.7 6.7 3.7 9 1.6 1.7 4800 1.4 6.7 3.0 11.2 4.7 11.0 7.7 11.6 7.4 7.2 3.7 9 1.6 1.9 4900 1.5 5.6 2.5 12.0 3.6 9.6 8.7 11.2 7.6 6.9 3.8 9 1.6 1.9 5000 1.5 4.1 3.5 11.9 3.3 8.3 9.6 9.8 9.9 6.9 3.8 9 1.6 1.5 5100 1.2 6.1 6.8 10.5 5.6 11.7 10.3 10.0 12.2 8.3 3.6 9 2.0 2.4 5200 1.1 7.1 5.8 9.3 6.7 13.7 11.0 7.6 16.4 8.7 4.5 9 2.1 1.6 5300 1.5 5.5 4.6 9.8 4.0 12.3 10.5 6.0 21.9 8.5 6.1 9 1.8 1.8 5400 1.5 4.2 4.0 10.9 4.5 10.8 9.5 6.4 21.1 8.1 5.9 9 1.9 2.5 5500 1.5 3.9 1.7 11.2 3.2 9.9 9.4 6.6 15.8 7.0 4.9 9 1.7 2.8 5600 1.5 3.0 2.0 10.2 4.0 9.2 11.0 7.8 9.1 6.4 3.8 9 1.7 1.6 5700 1.5 2.3 3.8 9.1 3.6 8.6 12.4 6.4 7.4 6.1 3.6 9 1.4 1.0 5800 1.5 3.6 4.9 8.1 0.9 8.0 12.0 10.4 9.4 6.5 4.0 9 1.4 1.3 5900 1.3 4.3 4.8 7.3 2.7 7.9 10.8 11.7 10.5 6.8 3.8 9 1.2 1.2 6000 1.2 4.0 4.6 6.5 3.6 7.7 9.4 7.1 9.2 5.9 2.8 9 1.0 0.6 6100 1.0 3.5 4.9 6.1 5.0 7.6 7.5 8.4 5.5 2.5 8 1.3 1.0 6200 0.8 2.7 4.2 5.8 4.1 8.1 5.6 10.1 5.2 2.9 8 1.8 0.9 6300 0.7 2.7 4.8 6.4 2.6 8.9 5.0 10.9 5.3 3.4 8 1.7 1.8 6400 0.8 2.2 6.5 7.7 4.2 9.8 4.8 10.8 5.9 3.5 8 1.5 1.3 6500 1.0 2.4 5.9 8.8 3.8 10.5 4.8 7.5 5.6 3.3 8 1.6 0.6 6600 0.9 2.9 4.3 8.7 3.3 11.0 5.0 6.4 5.3 3.3 8 1.3 0.7 6700 0.7 2.0 3.0 8.3 3.4 11.5 5.2 5.7 5.0 3.5 8 1.4 1.1 6800 0.7 2.1 3.9 8.4 2.6 11.9 5.4 5.8 5.1 3.7 8 1.9 1.3 6900 0.9 2.7 5.8 8.8 3.8 11.9 5.6 6.7 5.8 3.5 8 1.4 1.9 7000 1.2 3.9 6.6 9.2 3.2 11.6 5.8 7.5 6.1 3.4 8 1.3 0.7 7100 1.9 2.9 4.6 9.6 4.1 11.3 6.0 6.4 5.8 3.2 8 1.3 0.8 7200 2.4 2.5 4.1 10.9 4.4 11.0 6.2 7.4 6.1 3.4 8 1.4 1.1 7300 2.1 2.3 4.2 12.6 3.5 10.5 6.2 10.0 6.4 4.1 8 1.3 0.7 7400 1.9 2.5 4.4 14.3 3.5 10.1 6.1 10.4 6.6 4.5 8 1.6 1.2 7500 1.9 3.3 3.1 15.8 3.0 9.6 6.0 8.4 6.4 4.7 8 1.3 1.4 7600 2.0 2.2 3.7 15.3 3.5 9.4 5.8 8.7 6.3 4.6 8 1.5 1.9 7700 1.5 1.4 5.6 14.3 4.0 9.4 5.7 10.7 6.6 4.6 8 1.7 2.0 7800 0.8 3.0 7.5 13.4 5.4 9.3 5.5 7.0 6.5 3.9 8 1.9 1.6 7900 0.9 4.1 6.1 12.5 2.9 9.4 5.4 9.3 6.3 3.8 8 1.5 1.5 8000 1.2 5.3 5.2 11.5 2.4 9.8 5.3 9.0 6.2 3.6 8 1.6 1.4 8100 1.5 5.9 7.8 10.3 3.6 10.3 5.1 7.2 6.5 3.1 8 1.9 1.3 8200 1.8 3.9 6.3 9.1 2.7 10.8 5.0 6.4 5.8 3.1 8 1.8 1.7 8300 2.1 4.3 4.5 7.9 3.2 11.0 4.8 6.8 5.6 2.9 8 2.2 1.0 8400 2.2 4.4 4.1 6.7 4.6 11.1 4.7 8.4 5.8 2.8 8 2.0 2.3 8500 1.9 3.5 5.6 5.7 2.8 11.2 4.5 8.6 5.5 3.1 8 2.0 2.6 8600 1.6 3.2 7.1 6.1 2.2 11.4 4.4 9.1 5.6 3.5 8 1.4 2.1 8700 1.6 3.4 7.2 6.9 2.9 12.1 4.3 9.1 5.9 3.5 8 2.2 1.6 8800 1.5 3.6 3.5 7.6 4.5 12.8 4.1 7.7 5.7 3.6 8 1.9 1.8 8900 1.3 3.7 4.5 8.4 3.6 13.5 4.0 9.6 6.1 4.0 8 1.7 2.2 9000 1.1 4.8 5.9 9.1 1.4 12.8 9.7 6.4 4.4 7 1.8 1.6 9100 1.5 5.4 3.6 9.1 1.9 10.7 7.5 5.7 3.6 7 1.2 0.9 9200 1.7 4.2 2.3 8.5 2.4 8.6 6.3 4.8 3.0 7 1.3 1.2 9300 1.4 2.8 2.7 7.9 2.1 6.9 5.4 4.2 2.5 7 1.2 1.5 9400 1.2 4.6 4.3 7.2 3.8 7.2 5.6 4.8 2.1 7 1.0 1.1 9500 0.9 4.5 2.9 6.6 3.1 7.9 7.3 4.8 2.6 7 1.1 1.3 9600 0.5 4.3 2.5 6.3 1.0 8.7 5.1 4.0 2.9 7 1.1 1.4 9700 0.2 4.9 2.8 6.7 3.6 9.2 5.7 4.7 2.9 7 1.3 1.0 9800 1.3 5.7 2.0 7.2 2.2 9.6 6.2 4.9 3.1 7 1.2 0.9 9900 1.2 5.5 4.0 9.3 3.7 10.0 5.5 5.6 3.1 7 0.9 0.8 10000 0.2 3.0 5.7 14.6 1.5 10.3 6.0 5.9 5.1 7 0.8 0.5 10100 0.5 5.3 4.5 11.9 1.6 10.3 5.6 5.7 4.2 7 0.6 0.7 10200 0.8 9.8 5.0 8.1 1.6 10.2 7.6 6.2 3.8 7 0.5 10300 1.0 10.6 4.7 6.9 0.9 10.1 8.6 6.1 4.0 7 0.5 10400 0.9 7.7 2.9 8.8 0.4 10.5 5.9 5.3 4.0 7 0.8 10500 0.7 7.0 3.7 11.0 3.0 11.6 8.4 6.5 4.2 7 1.5 10600 0.9 7.1 2.6 12.7 1.5 12.3 5.4 6.1 4.9 7 1.5 10700 1.2 1.1 21.6 1.9 12.2 4.0 7.0 8.3 6 1.6 10800 0.6 4.0 35.0 1.6 11.8 3.3 9.4 13.2 6 1.4 10900 0.7 5.8 18.0 2.5 10.6 4.1 7.0 6.4 6 1.6 11000 0.8 6.9 7.4 9.4 5.1 5.9 3.2 5 1.4 11100 1.5 8.5 10.5 5.3 6.5 3.9 4 1.7 11200 0.9 7.5 12.3 5.0 6.4 4.8 4 1.8 11300 0.9 10.7 11.3 4.9 6.9 5.0 4 2.3 11400 0.3 9.3 8.5 5.7 6.0 4.1 4 2.7 11500 0.8 7.7 7.3 6.8 5.7 3.2 4 5.4 11600 0.5 8.1 8.5 5.7 4.5 3 11700 0.5 7.2 9.3 5.7 4.6 3 11800 0.8 6.0 9.4 5.4 4.4 3 11900 0.8 6.5 9.5 5.6 4.4 3 12000 0.4 4.7 9.7 4.9 4.6 2