Demerara Rise Cretaceous and Paleogene Mg/Ca Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!! NAME OF DATA SET: Demerara Rise Cretaceous and Paleogene Mg/Ca Data LAST UPDATE: 12/2005 (Original receipt by WDC Paleo) CONTRIBUTORS: Karen L. Bice IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2005-085 SUGGESTED DATA CITATION: Bice, K.L., et al. 2005. Demerara Rise Cretaceous and Paleogene Mg/Ca Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2005-085. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Bice, K.L., G. Layne and K. Dahl. 2005. The application of SIMS for measuring Mg/Ca in rare, delicate or altered planktonic foraminifera: Examples from the Holocene, Paleogene and Cretaceous. Geochemistry, Geophysics, Geosystems, 6, Q12P07, doi:10.1029/2005GC000974. ABSTRACT: Secondary ion mass spectrometry (SIMS) is useful for measuring Mg/Ca in both primary calcite and diagenetic minerals in planktonic foraminifera. The excellent spatial resolution (<10 micron) and small amount of material removed (< 2 ng) makes it easy to avoid targets that include obvious embedding material and encrusting or infilling minerals such as secondary calcite and authigenic clays in diagenetically altered samples. Because analyses can be performed on individuals, SIMS is also a viable technique for generating Mg/Ca values from sediment samples in which foraminifera are rare or have low mass. For clean primary calcite samples, Mg/Ca ratios from SIMS compare well to those obtained using inductively coupled plasma mass spectrometry (ICP-MS), while maintaining information regarding the true variability of elemental ratios within individual tests. For samples with secondary calcite or stubbornly adhering clays, SIMS enables us to accurately measure primary calcite compositions and to assess and reconcile contamination problems in bulk samples analyzed by solution-based ICP-MS. We have observed that SIMS is an invaluable and reliable tool for the identification and avoidance of problems of diagenesis and the analysis of rare or delicate planktonic foraminifera. However, because of operator time required to properly target delicate (thin-walled) or contaminated planktonic foraminifera, SIMS may not be feasible for Mg/Ca studies where large numbers (hundreds) of samples must be processed and bulk measurements on multiple individuals will suffice. ADDITIONAL REFERENCE: Bice, K.L., D. Birgel, P.A. Meyers, K. Dahl, K.-U. Hinrichs, and R. D. Norris. Accepted. A multiple proxy and model study of Cretaceous upper ocean temperatures and atmospheric CO2 concentrations. Paleoceanography, in press. (preprint pdf available at http://www.whoi.edu/science/GG/people/kbice/home.html) GEOGRAPHIC REGION: Demerara Rise, tropical central Atlantic PERIOD OF RECORD: Cretaceous - Paleogene, ~100 MMYrBP - ~30 MMYrBP DESCRIPTION: The data are Mg/Ca and Al/Ca ratio values determined by inductively coupled plasma mass spectrometry (ICP-MS)and Mg/Ca values determined by secondary ion mass spectroscopy (SIMS). The samples are a set of low resolution planktonic foraminifera from DSDP Site 144 and ODP Sites 1257, 1258 and 1260. Age of the samples is Cretaceous through middle Eocene. Site 1257 9° 27'N 54° 21'W 2951m. Site 1258 9° 26'N 54° 44'W 3192m. Site 1260 9° 16'N 54° 33'W 2549m. DATA: Ratios in mmol/mol Preservation Key E = Excellent VG= Very Good G = Good M = Moderate Age Key MEOC = Middle Eocene EEOC = Early Eocene LPAL = Late Paleocene MAAS = Maastichtian SAN = Santonian TUR = Turonian CEN = Cenomanian LALB = Late Albian Sample Interval(cm) Depth(MBSF) Depth(MCD) ForamZone NannoZone AGE SPECIES Preservation Mg/Ca Method Al/Ca Method Note 207-1257A-10X-4 39-41 78.20 78.20 P6 NP12 EEOC M. crassata VG 3.72 ICPMS 8.50 ICPMS 207-1257A-11X-2 15-17 84.50 84.50 P5 NP9 EEOC M. velascoensis VG 3.51 ICPMS 10.35 ICPMS 207-1257A-11X-2 15-17 84.50 84.50 P5 NP9 EEOC M. velascoensis VG 3.95 SIMS 207-1257A-12X-3 62-64 96.20 96.20 P4 NP9 LPAL M. velascoensis VG 3.53 ICPMS 4.25 ICPMS 207-1257A-12X-3 62-64 96.20 96.20 P4 NP9 LPAL M. velascoensis VG 3.54 SIMS 207-1257A-13X-2 60-62 104.30 104.30 P4 NP8 LPAL M. velascoensis G 3.39 ICPMS 114.10 ICPMS Al/Ca from ICP-MS suggests clay contamination 207-1257A-13X-2 60-62 104.30 104.30 P4 NP8 LPAL M. velascoensis G 3.37 SIMS 207-1257A-14X-3 38-40 115.20 115.20 P4 NP8 LPAL M. velascoensis VG 3.43 ICPMS 29.12 ICPMS 207-1257A-14X-3 38-40 115.20 115.20 P4 NP8 LPAL M. velascoensis VG 3.88 SIMS 207-1257C-3R-3 130-150 105.50 107.50 P4 NP8 LPAL M. velascoensis G 3.74 ICPMS 45.63 ICPMS 207-1257C-3R-3 130-150 105.50 107.50 P4 NP8 LPAL M. velascoensis G 3.40 SIMS 207-1257C-5R-2 130-150 123.30 126.00 P4 NP8 LPAL M. velascoensis G 3.13 ICPMS 30.63 ICPMS 207-1257C-5R-2 130-150 123.30 126.00 P4 NP8 LPAL M. velascoensis G 3.61 SIMS 207-1257C-11R-1 84-89 178.84 181.40 CC15-16 SAN H. delrioensis E 3.60 ICPMS 589.45 ICPMS Al/Ca from ICP-MS suggests clay contamination 207-1257C-11R-1 84-89 178.84 181.40 CC15-16 SAN H. delrioensis E 3.95 SIMS 207-1257C-13R-2 120-140 200.00 202.60 CC13 TUR H. globulosa E 5.73 ICPMS 0.11 ICPMS 207-1257C-13R-2 120-140 200.00 202.60 CC13 TUR W. baltica E 4.45 ICPMS 8.44 ICPMS 207-1257C-14R-1 76-82 207.76 210.30 CC10-11 TUR H. globulosa E 4.97 ICPMS 6.88 ICPMS 207-1257C-14R-1 76-82 207.76 210.30 CC10-11 TUR W. baltica E 3.96 ICPMS 4.19 ICPMS 207-1258A-6R-2 40-42 44.70 45.20 P9 NP14 EEOC M. aragonensis VG 3.55 ICPMS 32.95 ICPMS 207-1258A-6R-2 40-42 44.70 45.20 P9 NP14 EEOC M. aragonensis VG 4.00 SIMS 207-1258A-7R-2 15-17 53.85 54.80 P9 NP13 EEOC M. aragonensis G 4.08 ICPMS 21.59 ICPMS 207-1258A-25R-2 20-22 227.70 250.15 P4 NP7 LPAL M. aragonensis VG 3.14 ICPMS 6.78 ICPMS 207-1258A-25R-2 20-22 227.70 250.15 P4 NP7 LPAL M. aragonensis VG 3.36 SIMS 207-1258B-51R-2 10-20 427.85 452.04 KS19 CEN W. baltica G 4.59 ICPMS 3.37 ICPMS 207-1258B-54R-3 10-30 444.48 468.96 CEN H. delrioensis E 6.32 ICPMS 7.98 ICPMS 207-1258B-55R-3 68-88 448.37 475.20 NC9a LALB H. delrioensis E 5.85 ICPMS 7.71 ICPMS 207-1260A-18R-2 12-14 155.12 153.30 P11 NP15 MEOC M. aragonensis G 3.31 ICPMS 10.32 ICPMS 207-1260A-19R-2 22-24 164.92 163.11 P11 NP15 MEOC M. aragonensis G 3.28 ICPMS 2.67 ICPMS 207-1260A-20R-2 22-24 174.52 172.71 P10-11 NP15 MEOC M. aragonensis G 3.43 ICPMS 3.41 ICPMS 207-1260A-34R-2 20-22 309.10 308.02 P4 NP7 PAL M. velascoensis E 3.37 ICPMS 183.65 ICPMS Al/Ca from ICP-MS suggests clay contamination 207-1260B-34R-2 10-17 407.30 410.00 KS20/22 CC11 TUR H. delrioensis E 4.45 ICPMS 4.04 ICPMS 207-1260B-37R-1 10-16 434.60 437.02 CC10 CEN H. delrioensis VG 5.24 SIMS 207-1260B-39R-1 115-122 454.85 457.63 CC10 CEN H. delrioensis E 5.98 ICPMS 18.17 ICPMS 207-1260B-41R-1 114-120 473.84 478.00 CC10 CEN H. delrioensis E 5.61 ICPMS 4.75 ICPMS 14-144-4R-3 72-75 216.72 IC50 CEN H. delrioensis E 5.44 ICPMS 14-144-4R-3 72-75 216.72 IC50 CEN H. moremani E 7.90 ICPMS 14-144-4R-3 72-75 216.72 IC50 CEN Globogerinelloides E 6.26 ICPMS