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109   Ry                                                                        (a).                dif-   gath-
             Be       My                                                              represent   highlighted  in   up   back   the   when   followed
       Processing   Fe   Ry   Fe   Fe     f   Ay   Fe                                 raypaths     from   reflections   whereby   CMP   in   originally



             Re       As        Fy           Gather                                      three  CMP  traces   interface,  straight   distance   primary   error,   and   traces   to

          Common   ee   Ss,   Ae    !   Fy   Fei       CMP   Common                   for  three  shot  records.  Highlighted   the   to   increasing   “tune”   trial   applied   that  events

                      Shot2   s   Fy                                                   and  gather for   down   with   best   commonly   are   that

                                Shot3   Ss,      Db                    Le—                     directly   time   that   is   corrections   so

                                                                                      and  shot  gathers   diagram   (time   in  increase   velocities   process   (Tyyo)   Tyyo


                 Ry                                                                    b)  Raypath   intercept   location)   The   removes
             Gathers   x—   Fe   A,                                                   Raypath  diagram   traces.   T-axis   shot   to   hyperbolic   source.   determines   5.10).   (Fig.   time  moveout   velocity




            Shot   Ry   FR,   A,                Bin me  ee   ee                       Gather.a)   midpoint  (CMP)   =   ty   =  Tymo   analysis   stacked   are   normal   desired




                 1                                                                    5.9   three  common   Velocity   traces   ferent   A   ers.
            a    Sh ot                                                                FIGURE








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    =  RE  EN OR   =   and   :   Bay  sa   ser  "Fe   Compete   HN            g   3
          a)  Selected  raypath  and  gather  for  a  primary  reflection.   be   may   Certain   is  profile   be   must   of   reflection   can   Geldart,   are   in   taken   trace   hyper-


      Analysis   surface  multiple  on  raypath  diagram   data   Earth.   the   product   interpretation   processing   and   gathers   highlighted   gather,   3-fold   a  follows


      Waveform   5.8  FIGURE   shotpoint   shotpoint  gather.   the   that   the   that   final   literal   seismic   of   Sheriff   shot   traces   CMP   one   interface


      And                                                 is  method   within   created,  so   The   to   process   to   treatment   of   9   different   three   same   the   comprises   receiver   to
      Processing,                                         reflection   depth  mimicking   image   the   section.   cross   pitfalls  many   taken   steps   detailed   Chap.   1980;   from  traces   The  gathers.   5.9b;   Fig.   illustrations,   horizontal   a   Tymo   interface,




      Acquisition,                                        seismic   enhancing   geological   there   are   6).   general   and  thorough   Treitel,   and   1976).   process,   (CMP)   in  gather   subsequent   from  reflection       +   ty   =   Ty        to  source,



      Reflection:   ty                                    the   of   downward,   axis   at  aimed   a   of   as  however,   (Chapter   Sequence   the   of   More   below.   (Robinson   al.,   et  of Telford   the  midpoint  gather   CMP   the   in   steps   profile.   A       from   time



      Seismic   Reflection             Multiple           appealing-aspect   time   the   thus   are   representation   wisely,   profiles  reflection   descriptions   and   presented   elsewhere   In  Gather   common   as   comprise   5.9a   processing   seismic   Analysis   to:   travel   =   T,



      Chapter5   Primary               Surface            One   with  plotted   processing  steps   abstract   interpreted   seismic   Processing   Objectives   are   found   1995;  pp.  370-395   1.   rearranged   Fig.   in   bold   the  through   stacked   the   2.  Velocity   bola,  according   where:



               :                                         .      an       General   data   be   on
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