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200 km)             i

         11      km)                                                      Magma   to        pene-   crust.   kim-   depths,   more   limited   the   (upper   the   and   on   and

         Know!ecoe   Dritlholes   12   (to                                  up   (from      drillhole   continental   deep-seated   mantle   sample   is  knowledge   effectively,  within   basins   crust   constraints   crust   the



         Earth                                                                  observations  (surface  outcrops,  drillholes,  magma  reaching  observations  (controlled-source  seismic,   deepest   typical   of   upper   or   and  Earth   sedimentary   lower   the   provide   within
         Whole                                                                     the  outer  shells;  earthquake  seismic  waves  give  most  of  the   The   km.   of   exception   lower  crustal   the   into   Our   1.10).   probe,   can   about   data   seismic  velocities



              ss op                                                               mantle.  Geophysical   50  uppermost   thickness   the   half   the   (with   at   deeper   look   (Fig.  of  resolution   techniques   within   details   information   refraction  Seismic   cases,




              Surface                                                     ae    Direct   uppermost   on   the   in   than   intrusions  igneous   originated   that   km.   200   to   us   degrees   particular   show   data   provide   (“Moho”).   some   in   and,

                                                                           Waves   Earth)   formed   depth,  less   km   and   magma   upper   allow   data   varying   that  depth   reflection   years,  recent   transition   changes



                   Reflection   Refraction   If                          2   e   Seismic   Entire  Constraints  on  nature  of Earth’s  interior.  generally  sample  only  the  crust  and  flow)  provide  further  constraints  the  lower  mantle  and  core.   generally   12   about   to   eruptions   from   come   the  within   Geophysical   with  widely,  but   maximum   Seismic   in   and,   km)   crust/mantle   thickness   mantle.  uppermost




                   Seismic   and   Crust    Gravity/   Magnetics/   Flow   Heat   Earthquake   (Penetrate   1.10  FIGURE   surface)   field,  heat  potential   information  on   ”   materials   trates   Volcanic   berlites)   generally   the   by   Earth.   10   crustal










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                                                        give   geo-   1.9).   things   or   we   do   of   Earth,   that   less   know   (landing   them.  As   Likewise,   and   upper   lower   at   or   or   radius.   occa-   those
               RESOLUTION   Know)   We  (What   Great  Detail   }   A   tate   Bit   a  Quite   Some   Not Much   not   do  observations   detailed   a   from   (Fig.   time   in   back   about   less   far   time   in   back   only   not   diminishes.  The  concept   the   about   events  about   some   of  details   We  or-work).   lives   for   like   was   (Europeans   out   stand   civilizations),  Egyptian   vague.   and   deeper  probe   and  surface   deeper,  we  Going   the










                                                     time  and  going  deeper  into  the  Earth.   geophysical   get  could   Jooking   lifetimes,   farther   look   deteriorates;   known   is   what   know   we   great   also   school   to   grandparents   and   life  what daily   events   and   Jonger   we   as  ‘larger   Earth’s   mantle.   and   from   the   in   of  Earth’s   1/30th   Earth’s  within   during  surface
                                       System      in   or   we   than   to   our   in   we   As   observation   information   lifétimes,   but   homes   our  parents   some   Greek,   becomes   becomes   about   deal   uppermost   composition   entirely   observations,   km,  about   formed   the

                                     -
               TRE   EARTH      Surface  Earth's      Crust   (0-30  km)      Lithosphere   Asthenosphere   700 km)   (0  -     Lower  Mantle   Core   and   6300  km)   (700  -      resolution  going  back   models  example,   geology  surface   interior  analogous   is   happened   that   time.  grandparents’   of  quality   the   of  detail   appreciating   in   own   our   In   Wall);   Berlin   the   our   from   route   that shaped   about   less   far   history,  recorded   Rom






         Introduction          History               Analogy  showing  diminishing   not   (for   wise   about  information   project).   KNOWLEDGE   Earth’s   of   lot  events  about   and  parents’   the  Earth,   the   the  information,  but   important  therefore   spatially.   and   (the   of   fall   (the  observations   events  important   II),  but   War  moon; World   through   back   development  America;   between   can   we  features   We  Earth.   the   its  about  amoun





         Chapter 1   GEOLOGIC   TIME   Lifetime   Our   Recorded   §,000 years)   (0  -   Phanerozoic   600,000,000 years)   Precambrian   (600,000,000  -  4,600,000,000 years)   is  direction   us   better   mapping   logic   EARTH   knowledge   Our   a  know   We   our   from   within  deeper   Jess   have   is  resolution   temporally   both   history  shaped   important   of  some   the   on   continue   we   coming   to   time   the   but   of   scale   the   into  deeper   fair




         10                             -   (0     1.9  FIGURE   '   WHOLE
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