Arctic Ocean Paleocene Mollusc Stable Isotope Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!! NAME OF DATA SET: Arctic Ocean Paleocene Mollusc Stable Isotope Data LAST UPDATE: 7/2006 (Original receipt by WDC Paleo) CONTRIBUTOR: Karen Bice, Woods Hole Oceanographic Institution IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2006-069 SUGGESTED DATA CITATION: Bice, K.L., et al. 2006. Arctic Ocean Paleocene Mollusc Stable Isotope Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2006-069. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Bice, K.L., M.A. Arthur, and L. Marincovich, Jr.. 1996. Late Paleocene Arctic Ocean shallow-marine temperatures from mollusc stable isotopes. Paleoceanography, vol. 11, No. 3, pp. 241-249. ABSTRACT: Late Paleocene high-latitude (80 deg N) Arctic Ocean shallow-marine temperatures are estimated from molluscan d18O time series. Sampling of individual growth increments of two specimens of the bivalve Camptochlamys alaskensis provides a high-resolution record of shell stable isotope composition. The heavy carbon isotopic values of the specimens support a late Paleocene age for the youngest marine beds of the Prince Creek Formation exposed near Ocean Point, Alaska. The oxygen isotopic composition of regional freshwater runoff is estimated from the mean d18O value of two freshwater bivalves collected from approximately coeval fluviatile beds. Over a 30 - 34‰ range of salinity, values assumed to represent the tolerance of C. alaskensis, the mean annual shallow-marine temperature recorded by these individuals is between 11 deg and 22 deg C. These values could represent maximum estimates of the mean annual temperature because of a possible warm-month bias imposed on the average d18O value by slowing or cessation of growth in winter months. The amplitude of the molluscan d18O time series probably records most of the seasonality in shallow-marine temperature. The annual temperature range indicated is approximately 6 deg C, suggesting very moderate high-latitude marine temperature seasonality during the late Paleocene. Based on analogy with modern Chlamys species, C. alaskensis probably inhabited water depths of 30-50 meters. The seasonal temperature range derived from d18O is therefore likely to be damped relative to the full range of annual sea-surface temperatures. High-resolution sampling of molluscan shell material across inferred growth bands represents an important proxy record of seasonality of marine and freshwater conditions applicable at any latitude. If applied to other regions and time periods, the approach used here would contribute substantially to the paleoclimate record of seasonality. GEOGRAPHIC REGION: North Slope of Alaska (Prince Creek Fm., Ocean Point, Alaska) PERIOD OF RECORD: Danian, late Paleocene. DESCRIPTION: The data consist of oxygen and carbon isotope measurement of carbonate samples microdrilled from sequential growth increments of 2 specimens of the bivalve Camptochlamys alaskensis. The samples were collected by L. Marincovich, Jr., from the Prince Creek Formation at Ocean Point, North Slope, Alaska, Lat. 70.0833N, Long. 151.3667W. At the time of publication (1996), the age of the samples was estimated to be Danian. DATA: 1. SAMPLE C-1. Camptochlamys alaskensis, (Danian) Prince Creek Fm., Ocean Point, North Slope, Alaska; shallow marine Location: 70.0833 deg N, 151.3667 deg. W Column 1: Sample ID Column 2: d18O (PDB) Column 3: d13C (PDB) Column 4: Sample ID Column 5: d18O (PDB) replicate Column 6: d13C (PDB) replicate C-1 Isotope Data C-1 Replicates Sample d18O d13C Sample d18O d13C 1 C-1 -2.76 4.29 1 C-1 -2.57 4.05 2 C-1 -1.94 3.93 2 C-1 -2.35 4.3 3 C-1 -2.05 3.95 3 C-1 -2.11 3.9 4 C-1 -2.07 3.55 4 C-1 -2.05 3.47 5 C-1 -1.99 3.44 5 C-1 -2.11 3.42 6 C-1 -2.30 3.59 6 C-1 -2.45 3.74 7 C-1 -2.37 3.66 7 C-1 -2.34 3.67 8 C-1 -2.54 3.38 8 C-1 -2.34 3.34 9 C-1 -2.63 3.17 9 C-1 -2.69 2.91 10 C-1 -2.66 2.84 10 C-1 -2.63 2.54 11 C-1 -2.71 3.27 11 C-1 -2.52 3.27 12 C-1 -2.83 3.24 12 C-1 -2.75 3.14 13 C-1 -2.53 3.74 13 C-1 -2.78 3.79 14 C-1 -2.62 4.05 14 C-1 -2.43 3.97 15 C-1 -2.58 4.14 15 C-1 -2.44 4 16 C-1 -2.64 4.06 16 C-1 -2.7 4 17 C-1 -2.59 3.98 17 C-1 -2.55 3.79 18 C-1 -2.96 3.86 18 C-1 -2.6 4.1 19 C-1 -2.53 4.67 19 C-1 -2.48 4.58 20 C-1 -2.29 4.25 20 C-1 -2.48 4.48 21 C-1 -2.69 3.99 21 C-1 -2.7 3.68 22 C-1 -2.91 3.63 22 C-1 -2.68 3.04 23 C-1 -2.27 4.14 23 C-1 -2.31 4.19 24 C-1 -2.35 4.55 24 C-1 -2.17 4.6 25 C-1 -2.07 4.42 25 C-1 -2.07 4.13 26 C-1 -2.14 3.87 26 C-1 -2.26 3.82 27 C-1 -2.57 3.77 27 C-1 -2.11 3.6 28 C-1 -2.14 3.38 28 C-1 -2.02 3.56 29 C-1 -2.10 3.42 29 C-1 -1.91 3.61 30 C-1 -1.91 3.78 30 C-1 -1.86 3.69 31 C-1 -1.78 3.76 31 C-1 -1.62 3.45 32 C-1 -1.64 3.38 32 C-1 -1.84 3.48 33 C-1 -1.54 3.47 33 C-1 -1.73 3.49 34 C-1 -1.96 3.60 34 C-1 -1.97 3.74 35 C-1 -2.12 3.91 35 C-1 -2.05 3.93 36 C-1 -2.35 3.88 36 C-1 -2.08 3.75 37 C-1 -2.32 3.83 37 C-1 -2.33 3.81 38 C-1 -2.46 4.13 38 C-1 -2.52 4.17 39 C-1 -2.60 4.06 40 C-1 -2.86 4.26 41 C-1 -2.61 3.95 42 C-1 -2.33 3.71 43 C-1 -2.33 3.73 44 C-1 -2.10 3.67 45 C-1 -1.62 3.32 46 C-1 -1.56 3.13 47 C-1 -2.03 3.55 48 C-1 -3.50 4.60 49 C-1 -3.19 4.44 50 C-1 -3.14 4.52 51 C-1 -2.97 4.37 52 C-1 -2.88 4.35 53 C-1 -2.84 4.23 54 C-1 -2.49 3.83 55 C-1 -2.24 3.87 56 C-1 -3.37 3.85 57 C-1 -3.62 4.27 58 C-1 -3.68 4.20 59 C-1 -3.27 4.06 60 C-1 -4.00 3.87 61 C-1 -4.78 3.71 2. SAMPLE C-2. Camptochlamys alaskensis, (Danian) Prince Creek Fm., Ocean Point, North Slope, Alaska; shallow marine Location: 70.0833 deg N, 151.3667 deg. W Column 1: Sample ID Column 2: d18O (PDB) Column 3: d13C (PDB) Sample d18O(PDB) d13C(PDB) 1 C-2 -3.34 2.89 2 C-2 -2.61 2.88 3 C-2 -2.70 2.70 4 C-2 -2.46 2.67 5 C-2 -2.60 2.88 6 C-2 -2.60 2.95 7 C-2 -2.71 3.55 8 C-2 -2.89 3.60 9 C-2 -2.63 3.55 10 C-2 -2.77 3.57 11 C-2 -2.50 4.01 12 C-2 -1.96 3.52 13 C-2 -2.00 3.70 14 C-2 -2.06 3.35 15 C-2 -1.93 3.76 16 C-2 -2.34 3.79 17 C-2 -2.42 3.87 18 C-2 -2.72 4.07 19 C-2 -2.67 3.97 20 C-2 -3.05 4.19 21 C-2 -2.83 4.19 22 C-2 -2.92 4.01 23 C-2 -3.11 3.64 24 C-2 -2.94 4.01 25 C-2 -2.59 3.91 26 C-2 -2.50 4.09