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                                                             Page 1                  ==================================                 =    DEEP SEA DRILLING PROJECT   =                 =   X-RAY MINERALOGY DATA BASE   =                 ==================================   I. INTRODUCTION  A. BACKGROUND AND METHODS    This data set results from x-ray diffraction analyses made by the    University of California at Riverside X-ray Mineralogy Laboratory which    operated from Leg 1 through Leg 37 under DSDP contract.  There are    14,578 individual analyses in the data set.  These are distributed    among the three sample fractions as follows -            Bulk:    > 20 microns            = 7005 analyses           Silt: 20 -  2 microns            = 3645 analyses           Clay:    <  2 microns            = 3928 analyses     The silt and clay fractions are decalcified with buffered acetic acid    and thus calcite and other such minerals will not be found in these    fractions.     The x-ray data for each of the Legs 1 through 37 is published in the    respective Initial Report of the Deep Sea Drilling Project along with    useful ancillary information that is not included in the file described    here.  Because the Riverside laboratory used a variety of methods to    assign subbottom depths to the samples, it is recommended that the    Initial Reports be consulted whenever it is important to know how    down-hole sample positions were determined on a particular leg.   B. LEGS IN DATA SET    The data set comprises analyses from Legs 1 through 37.  Bulk fraction    analyses exist for each leg.  Legs which do not have analyses for    either the silt or the clay fraction are listed below.                    Silt:  No analyses for Legs 1,2,3,5,7,10 and 11                   Clay:  No analyses for Legs 1,2,3,4,5 and 6     In the Initial Reports there are histograms and other non-numerical    presentations for some of the above listed 'missing' fractions.   C. REFERENCES    The laboratory procedure for the x-ray analyses is discussed in Volume    28 of the Initial Reports of the Deep Sea Drilling Project.     For an overview of this data set see G.  Ross Heath, 1984.  X-ray    Mineralogy Studies.  In G.  Ross Heath (Ed.), Sedimentology, Physical    Properties, and Geochemistry in the Initial Reports of the Deep Sea    Drilling Project Volumes 1-44:  An Overview, World Data Center A for                                                      DSDP/X-RAY 6/85                                                                   Page 2      Marine Geology and Geophysics Report MGG-1, pp.  71-91.   D. RECORD AND FILE DESCRIPTION    The encoded data set is segregated by mineral fraction into three    separate files.  Each file is written in ascending order by 'DSDP    label' (record columns 1-29) in the format described below.     An individual x-ray analysis will comprise one or more 120 character    length logical records in the following format.     Character     FORTRAN    Position      Format           Field Content    =========     =======          =============      1-  2        (A2)             leg number     3-  6        (A4)             hole     7-  9        (A3)             core    10- 11        (A2)             section designator or blank field    12- 19        (F8.2)           subbottom depth (M) of top of sample                                   interval or top of cored interval    20- 27        (F8.2)           subbottom depth (M) of bottom or middle                                   of sample interval        28        (A1)             fraction: B=bulk,S=silt,C=clay        29        (I1)             relative position of record in sample:                                       0      = lead record segment                                       1,2,.. = following record segments                                                (as needed)        30        (1X)             blank field    31- 32        (I2)             number of minerals in sample    33-120        11(A4,F4.1)      mineral mnemonic/weight percent                                   couplets for those minerals occurring                                   in sample(i.e., zero percentages do                                   not occur).       Note:  The mnemonic/percentage couplets occurring in columns 33-120             will usually begin with the mnemonics DIFF and AMOR for the             analyses from Legs 10 through 37.  Although these are not             minerals themselves (see table below), they are included in             the total mineral count of an analysis as given in columns             31-32.  The percentages attached to the actual minerals are             weight percents relative to the particular sample and             fraction, but for some analyses these values have not been             normalized to 100 percent.  Despite the fact that percentages             are written to 1/10 of 1 percent, this data set must be viewed             as semiquantitative.  In some cases, percentages are negative             to indicate one of the following relative abundance codes.                  -5.0 = TRACE                 -25. = PRESENT                 -65. = ABUNDANT                 -99. = MAJOR              In addition, a mineral weight percentage may be given as              "100." to indicate 100%.                                                   DSDP/X-RAY 6/85                                                                   Page 3   E. X-RAY MINERAL MNEMONIC LIST:                 Inventory of DSDP/UC Riverside X-ray Minerals                      Over All Legs and All Fractions                    (ordered by frequency of occurrence)                                       Four                                     Character      Mineral                        Mnemonic        No. of Occurrences      =======                        ========        =================        'diffuse scattering' measure   DIFF            10192      'amorphous material' measure   AMOR            10171       QUARTZ                         QUAR            11999      MICA                           MICA             9160      PLAGIOCLASE                    PLAG             9059      MONTMORILLONITE                MONT             7546      CHLORITE                       CHLO             5420      CALCITE                        CALC             4942      KAOLINITE                      KAOL             4911      K-FELDSPAR                     K-FE             4635      CLINOPTILOLITE                 CLIN             2389      PYRITE                         PYRI             2017      BARITE                         BARI             1611      PALYGORSKITE                   PALY             1402      AMPHIBOLE                      AMPH             1148      PHILLIPSITE                    PHIL             1145      CRISTOBALITE                   CRIS              829      DOLOMITE                       DOLO              762      AUGITE                         AUGI              579      GOETHITE                       GOET              371      MAGNETITE                      MAGN              352      TRIDYMITE                      TRID              349      GYPSUM                         GYPS              329      HALITE                         HALI              305      ANALCITE                       ANAL              296      HEMATITE                       HEMA              257      ARAGONITE                      ARAG              177      ANATASE                        ANAT              175      SIDERITE                       SIDE              135      FELDSPAR (undifferentiated)    FELD               98      APATITE                        APAT               75      GIBBSITE                       GIBB               62      SEPIOLITE                      SEPI               43      SANIDINE                       SANI               29      RHODOCHROSITE                  RHOD               28      MAGNESIAN CALCITE              MGCA               26      CALCIUM DOLOMITE               CADO               25      MIXED LAYER CLAY               MIXL               20      BEIDELLITE                     BEID               16                                                    DSDP/X-RAY 6/85                                                                   Page 4        TALC                           TALC                8      ANHYDRITE                      ANHY                6      "variety of MONTMORILLONITE"   2-MO                6      ILMENITE                       ILME                5      ERIONITE                       ERIO                4      CHABAZITE                      CHAB                3      CUPRITE                        CUPR                3      CELESTITE                      CELE                2      PSILOMELANE                    PSIL                2      BASSANITE                      BASS                1      SPHALERITE                     SPHA                1      ILLITE                         ILLI                1       "UNKNOWNS"                     U- 1              285                                     U- 2              117                                     U-1               116                                     U-2               116                                     U-10               66                                     U- 4               55                                     U- 3               53                                     U-11               44                                     UNKN               16                                     U- 5                9                                     U-12                6                                     U- 6                5                                     U- 7                3                                     U- 9                3                                     U- 8                2                                                                              DSDP/X-RAY 6/85                                                                  Page 5   NGDC NOTES:  (list of deviations from field descriptions)   Please note that additional xray mineralogy data are described   in "xrdwhoi" documentation.  Description of deviation                    Record Number(s) =======================================     ================  Weight percentage: col 45-48                6130,6132-6144,6147,6166,6169,    - negative weight percentages given      6171,6173,6175,6189-6195,6200,    are not legal relative abundance         6235-6251,6570,6626,6660    codes as described in documentation  Mineral weight percentage does not total    157,302,369,377,1245,1570,1588,    to one hundred                           1602,1609-1610,1619,1853-1854,                                             1896,1909,1912,1929,1999,2323,                                             2356,2383,2404,2475-2477,2732,                                             2876,3278-3687,3689-3713,3715-                                             4195,4197-4296,4298-4306,4308-                                             4309,4311-4371,4374-4381,4383-                                             4434,4436-5257,5259-5264,5268,                                             5270-7167                                                                                    DSDP/X-RAY 6/85 

X-ray mineralogy data base- background and methods

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