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166
       “
       ee
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       ye
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                                THE
    air
                                               berger
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                            salinity.
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         terms. of
                       two
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                                          However,
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                                SOURCE
                     a
      for
                                        conductive
                                                                                                                 OPEN-HOLE
                                          SP
                       sodium
                                                                                                            SPONTANEOUS-POTENTIAL
                 fig.
                         known
                                OF
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                   solution
                                               Well  Services.
                                        path
             current

                             of
                 9.3).
        solutions
          solution.
                                                                   SHALE
                               THE
                   will
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                           understand
               ions
                                      generation
                         about
      weak
                     permeable
                               SP
                       chloride
             :
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                                                                                                                 LOGGING  MEASUREMENTS
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                             water
                           little
          In
                                         is
                                       is



                                                                                                                167
                                    :

                                                                                                                9:
                  so
                             the
     ‘bed
                      ‘A
          effect
                                                                                                                THE
            cations
        chapter
                          between
              minerals
                                                                                                                SP
     from
                        potential.
                                    FIGURE  9.2
                      similar
                                                                                              Ground
        27.)
            may
                          the
                    construction
                               concentrated
     the
                                                                                                                LOG
                phenomenon
                  permeable

                                                            SP
              whose
                  to
       Since
                          mud
     saline
                                                                                              Electrode
                  Cl
                    of  shale
                occurs
                                                                                                     Voltmeter
                      “battery”
       Na*
                                                                                                       Recording
                               solution
          manifests  itself  in
                                                            Electrode
                                    Recording  the  SP.
              exterior
                          filtrate
                  ions.
       ions
                    beds.
                               (see

         the‘
                      arises
                  A
     formation
            temporarily clin
         él
                because
                          and
                                                                                         qo
                               fig.
                      in

           ,
                                             Mud
                             liquid-junction potential  (E yp.
                    Shales
                of
                  shale
                          the
              surfaces
                      the
     water

                              9.4).
                    are
         Ctrical
                            The
           (This
                the;
     to
                  thus
                                                                                          ~~]
                              The
              havé
     the
                  acts
           same
       effectively  manage
                          formation
                            greater
                      formation
     less
                                                                       Formation
         behavior
       to
                    permeable
                            the
                crystalline
         of
                  ‘as"an
                              potential
                    to
              €xchange
                      from
                          water,
                              is
     saline
                                    Courtesy Dresser Atlas,  Dresser
           surface
                    Na*
         shaly
                  ionic
                      the
                          the
             sites
                            contrast
       penetrate
     mud
                structure

                    ions
                            in


             to

       the
                              referred
                  sieve.

                of
                          larger
                    but
                              to
             which
           conductance

     column,
       shale

         sands—see
                  This
                            salinity
                clay
                    not
                              as
                          this
                      molecular
                                    Industries,  Inc.
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