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                                                              Page 1                  ================================                =   DEEP SEA DRILLING PROJECT  =                =  CARBON/CARBONATE DATA BASE  =                ================================   I.  INTRODUCTION                                                                    A.  BACKGROUND AND METHODS                                                                        The Deep Sea Drilling Project (DSDP) Carbon/Carbonate data      base contains the results of chemical analyses designed to      determine the weight percentage of total carbon, organic      carbon, and calcium carbonate in deep sea sediments.      Although other carbonates may be present, all acid-soluble      carbon is calculated as calcium carbonate.  Included in the      data set is carbonate bomb data collected independently by      Drs. T.C. Moore, B. Simoneit, R. Kidd, D.S. Cronan,      A.P. Lisitzen and Tj. van Andel.  Below is a list of methods      and the legs on which they were used.       Method                       Legs      ========================     ===========================      LECO 70-Second Analysis      1-9,15-23,28-31,33-34      LECO WR-12 Analysis          35-79      LECO Acid-Base Analysis      7,9-16,24-28,32      LECO (type unknown)          75      Wet Combustion               6      Gravimetric                  16      Gasometric Technique         75      CHN Analysis                 75,93      Carbonate Bomb Analysis      3,8,9,12,16,18-21,24,29-32,                                   41,42,47,49,50,63,64,68,                                   70-82,84-87,89,90,93-96       A short description of each method appears below, for a more      extensive explanation consult the reference section of this      document.        LECO METHODS:       The total carbon content of a sediment sample is determined      by measuring the thermal conductivty of the gaseous products      of pyrolysis of the sample.  The analysis may also be      conducted on an acidified sample to determine the organic      carbon content.  The weight percentages of total carbon      (TC), organic carbon (OC), and calcium carbonate (CaCO3) are      related by the equation:  (TC - OC) * 8.33 = CaCO3 .  The      actual file value for CaCO3 may vary from this formula by as      much as 1.67 percent (0.2 * 8.33) due to an early procedural      error which truncated rather than rounded the values      reported for total carbon and organic carbon.                                                 DSDP Carbonate 7/86                                                                  Page 2               LECO 70-Second Analyzer:           Measures the thermal conductivity of a set volume of           all the gaseous products liberated from the sample.            LECO WR-12 Analyzer:           Separates the liberated CO2 from the other combustion           products then measures it using a gas chromatograph           equipped with a thermal conductivity detector.            LECO Acid-Base Semi Automatic Carbon Determinator:           The liberated gas of carbon dioxide and oxygen is           volumetrically measured (corrected for STP) and then           passed through a potassium hydroxide solution which           preferentially absorbs carbon dioxide.  The volume of           gas is measured a second time.  The volume of the           carbon dioxide gas is the difference of the two           volumetric measurements.       Note:  "LECO" is an abbreviation for Laboratory Equipment      Corporation of St.  Joseph, Michigan.        CARBONATE BOMB METHOD:       The calcium carbonate content of a sample is determined by      measuring the increase in gas pressure caused by acidifying      a dried sediment sample in a closed vessel.  The percent      carbonate is then read from a pressure-concentration curve      constructed from standard runs.        GASOMETRIC METHOD:       This method of measuring the percent calcium carbonate was      used only on leg 75 sediments.  It employed a volumetric      technique outline by Hulsemann(1966).        GRAVIMETRIC METHOD:       This method of measuring the percent calcium carbonate was      used only on on leg 16 sediments.  It employed a technique      outlined by Cronan and Bode(1973).        CHN METHOD:       A Carbon-Hydrogen-Nitrogen (CHN) analyzer was used only on      legs 75 and 93 to measure the percent organic carbon in a      sample.                                                   DSDP Carbonate 7/86                                                                  Page 3        WET COMBUSTION METHOD:       The technique as mentioned in Lisitzin(1971) uses a      Knopp-Frezenius device to measure calcium carbonate and      organic carbon by the wet combustion method.  This method      was used only on leg 6 sediments.   B.  LEGS IN DATA SET       The data base contains data for legs 1-96 with the exception      of legs 46, 83, 88, 91 and 92.   C.  REFERENCES        Appendix III:  Shore-based Laboratory Procedures.  In:      Bader, R.G.  et al., 1970.  Initial Reports of the Deep Sea      Drilling Project, Volume IV. Washington (U.S. Government      Printing Office) pp. 745-753.       Boyce, R.E. and Bode, G.W., 1972, Carbon and Carbonate      Analyses, Leg 9, Deep Sea Drilling Project.  In:  Hays, J.D.      et al., 1972, Initial Reports of the Deep Sea Drilling      Project, Volume IX.  Washington (U.S. Government Printing      Office) pp. 797-816.       Cronan, D.S.  and Bode, G.W., 1973.  Carbon and Carbonate      Analyses, Leg 16.  In:  van Andel, T.H., Heath, G.R., et      al., 1973, Initial Reports of the Deep Sea Drilling Project,      Volume XVI.  Washington (U.S. Government Printing Office)      pp. 521-528.       Hulsemann, J., 1966.  On the Routine Analysis of Carbonates      in Unconsolidated Sediments.  J. Sediment. Petrol., Volume      36, pp. 622-625.       Lisitzin, A.P., et al., 1971.  Geochemical, Mineralogical,      and Paleontological Studies.  In:  Fischer, A.G., et al.,      1971, Initial Reports of the Deep Sea Drilling Project,      Volume VI.  Washington (U.S. Government Printing Office)      pp. 840-841.       Muller, G. and Gastner, M.,1971.  The "Karbonat-Bombe", a      Simple Device for the Determination of Carbonate Content in      Sediment, Soils, and Other Materials.  Neues Jahrbuch      Minearalogie.  Volume 10, pp. 466-469.                                                       DSDP Carbonate 7/86                                                                  Page 4   II.  FORMAT AND FIELD DESCRIPTIONS     A.  DATA FORMAT        Record length = 78 characters (34162 records)      (Originally 80, 2 blank fields removed by NGDC)       COLUMN   FIELD                                 FORMAT      ======   ===================================   ======        1-2    LEG                                     A2        3-5    SITE                                    A3        6      HOLE                                    A1        7-9    CORE                                    A3       10-11   SECTION                                 A2       12-15   TOP INTERVAL DEPTH (centimeters)        F4.1       16-19   BOTTOM INTERVAL DEPTH (centimeters)     F4.1       20-27   TOP OF CORE DEPTH (meters)              F8.2       28-35   SAMPLE DEPTH (meters)                   F8.2       36-41   PERCENT TOTAL CARBON                    F6.1       42-47   PERCENT ORGANIC CARBON                  F6.1       48-53   PERCENT CALCIUM CARBONATE (CaCO3)       F6.1       54-68   METHOD CODE                             A15       69-78   DATA SOURCE CODE                        A10     B. FIELD DESCRIPTIONS        The definition of leg, site, hole, core and section may be      found in the explanatory notes.  In addition, the special      core designations, as well as the methods of sample labeling      and calculating absolute sample depths are discussed.    INTERVAL DEPTH:       The depth, in centimeters, within a section at which the top      or bottom of a measurement was taken.  Values are encoded      with an implicit decimal point, therefore an encoded value      of 805 represents 80.5 centimeters.   CORE DEPTH:       The subbottom depth in meters to the top of the core.                                                    DSDP Carbonate 7/86                                                                  Page 5   SAMPLE DEPTH:       The subbottom depth in meters to the point of measurement.   PERCENT TOTAL CARBON:       The weight percent of total carbon measured by one of the      LECO analyzers.   PERCENT ORGANIC CARBON:       The weight percent of organic carbon measured by a LECO      analyzer, CHN analyzer or by the wet combustion method.   PERCENT CALCIUM CARBONATE:       The weight percent of calcium carbonate (CaCO3) may be      measured directly by the carbonate bomb, gasometric,      gravimetric or wet combustion methods.  It may also be      calculated from values determined for total and organic      carbon.    METHOD CODE:     CODE            METHOD (parameter measured)   =============   ==============================================   LECO            LECO (TYPE UNKNOWN) (total and/or organic)   LECO70          LECO 70-SECOND ANALYZER (total and/or organic)   LECO12          LECO WR-12 ANALYZER (total and/or organic)   LECOAB          LECO ACID-BASE ANALYZER (total and/or organic)   BOMB            CARBONATE BOMB (CaCO3 only)   CHN             CARBON-HYDROGEN-NITROGEN ANALYZER (organic)   GAS             GASOMETRIC ANALYSIS (CaCO3 only)   CHN/BOMB        CHN ANALYZER (organic carbon)/BOMB (CaCO3)   LECO/GAS        LECO (organic carbon)/GASOMETRIC (CaCO3)   GRAVIMETRIC     GRAVIMETRIC ANALYSIS (CaCO3 only)   WETCOMBUSTION   WET COMBUSTION (organic carbon and/or CaCO3)   LECOAB/LECO70   LECOAB (total carbon)/LECO70 (organic carbon)   LECO70/LECOAB   LECO70 (total carbon)/LECOAB (organic carbon)                                                          DSDP Carbonate 7/86                                                                  Page 6   DATA SOURCE CODE:    CODE          SOURCE                    LEGS   ===========   =======================   ======================   DSDP/SHORE    DSDP Shore laboratory     1-45,47-71,73,74,76-79   DSDP/CHAL     DSDP Shipboard            50,63,68,70-82,84-87,                                           89,90,93-96   LISITZIN      Dr. A.P. Lisitzin         6   CRONAN        Dr. David S. Cronan       16   KIDD          Dr. Robert Kidd           42   SIMONEIT      Dr. Bernd R. Simoneit     64   GARDNER       Dr. James V. Gardner      75   VANANDEL      Dr. Tjeerd H. Van Andel   19,20,21,30,31,32   MOORE         Dr. Theodore C. Moore     3,8,9,12,16,18,21,24,                                           29,30,31,32,41,47,49       NGDC NOTES: (list of deviations from field descriptions)  Description of deviation                       Record Number(s) =====================================          ================ Method code (CHN/GAS)not listed in             27146,27312,27346,27353,    documentation file                          27367,27514,27559,27603,                                                27606,27631,27670,27696,                                                27739,27789  Top interval depth exceeds bottom              33325                                                                        DSDP Carbonate 7/86 

Carbon/Carbonate data base - background and methods

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