??at

1
??atµ?µat??? ??S ?S ??T

• ??sta? ?ats?µpa???
• ?a????t?? ????
• ??? 2310-996123
• kvek _at_ topo.auth.gr

?07
2
?e?????? ??as??p?se??se ??se?? a??a?????????
e?d?af????t??

• ?a???t?µet???? (magnetometric survey)
• 2006 ??a te????? SQUID Superconducting Quantum
  Inteference Device (200 f???? p?? e?a?s??t?,
  ?at????? efa?µ????, a??. efa?µ???? 1-5 µ?t?a ??a
  ???? d??µa)
• ??e?t???? (resistivity survey)
• - 2006 ??e? te?????? GEEP / Geophysical
  Equipment Exploration Platform.
  Geomatrix/OhmMapper (10µ ß????)
• ?a??t?µet???? (gravimetric survey)
• ??e?t??µa???t??? (Ground Probing Radar)

?07
3
??ß?????af?a

• Parasnis, D.S. Principles of Applied Geophysics,
  Chapman Hall, 5th edition, 1997, ISBN 0 412
  64080 5
• ??a??s?µ? ap? t? ??ß??????? t?? ?etapt???a???
• S?µe??se??
• http//users.auth.gr/kvek/Y07_2008.ppt

4
?a???t?µet??a
5
??p?? ?a???t?µet??a
6
G?eße?? (t?p??? µa??. ??as??p?s?)

• .

7
?a??t?µet???? d?as??p?s? (g)

• ?as??eta? st? µ?t??s? t?? ep?t????s?? (g) t??
  ?????? ped??? t?? ßa??t?ta? (W) ?a? s???e???µ??a
  st?? µetaß???? t?? se ?e?t????? s?µe?a
• ?? µetaß???? t?? g ?fe????ta? st?? a??µ??????e?a
  t?? p????t?ta? t?? µa??? p?? ?????? ta s?µata
  st?? ep?f??e?a t?? ???.
• ?pa?te? t? ???s? ??????? µ?t??s?? t?? s?et????
  ßa??t?ta? (relative gravimeter), te??????
  epe?e??as?a? t?? a?????? pa?at???se??
  (pre-processing) ?a? µe??d?? a?a????? t??
  pa?at???se?? (gravity reductions)
• ????e? st?? µ?-?atast?ept???? (non-destructive)
  µe??d??? d?as??p?se?? ?p?? e??a? ?a? ? µa???t???
  d?as??p?s?, µ?a ?a? de? d???ete?e? ??te e?p?µpe?
  s?µa (?p?? s?µßa??e? st?? ??e?t????? d?as??p?se??
  ?a? st?? ??e?t??µa???t???? µe??d??? - georadar).

?07
8
G - d?as??p?s? ?? ??se??

• ?? ????? ped?? ????? V GM / r
• ? p??t? pa??????? dV/dr - GM / r2
• ?? ????? ped?? ßa??t?ta? W V F????e?t???
• ? p??t? pa??????? dW/dr e?e? µ???de? ep?t????s??
  (d??aµ? a?? µ???da µ??a?, ap? t? ???st? s??s? F
  mg)
• G???e? pa??????e?, d???µe?? Coriollis, µetaß????
  t?? ?????? pe??st??f?? ?a? ???e? ep?d??se??
  µetaß????? t? g ap? t?p? se t?p? ?a? ap? ??a se
  ??a.
• ? t?µ? t?? g st?? ep?f??e?a t?? ??? e??a? t?p???
  9.81 m/sec2
• 1 cm/sec2 1 gal (after G. Gallilei)
• 1 µm/sec2 1 g.u. (gravity unit)
• 1 mgal 10 g.u.

?07
9
g - d?as??p?s? ? µ?t??s? t?? g

• ? ep?t????s? t?? ßa??t?ta? µet??ta? µe
• s?et??? ßa??t?µet?a (p??ß??µa ? ast??e?a µe t??
  ??a / drift)
• ap???ta ßa??t?µet?a (p??ß??µa µe???? ??st??
  ?e?t?????a?)
• ? a???ße?a t?? µ?t??s?? µe s?et??? ßa??t?µet??
  e??a? t?? t???? t?? 0.2 - 0.4 g.u. (20-40 µgal),
  ??a?? st? ?a e?t?p?se? ?????t?ta 100 ??ß????
  µ?t??? se ??a ß???? 10-20 µ?t??? ??t? ap? t?
  st??µ? e?t??es?? t?? µet??se??.
• ??a??s?µa s?et??? ßa??t?µet?a
• LaCoste-Romberg
• Worden
• ??st?? a????? pe??p?? 60,000 e???
• Friedrich, J. Et al, Gravimetric examination of
  Hagia Sophias subsurface structure. Journal of
  Geodesy, 70, pp 645-651, 1996.

?07
10
Ground Probing Radar (GPR)

• ?? GPR ???s?µ?p??e?ta? st?? e?t?p?sµ? ?a? t?
  ?a?t????f?s? a?t??e?µ???? ta ?p??a ß??s???ta?
• 1. ?aµµ??a µ?sa st? ?daf??
• 2. p?s? ap? t????
• 3. µ?sa st? µ??a s?µpa???? s????d?µat?? (p?.
  op??sµ?? beton).
• ?as??? p?e????t?µa t?? µe??d?? e??a? ? d??at?t?ta
  e?t?p?sµ?? ?a? µ?-µeta?????? a?t??e?µ???? (d??ad?
  p?ast???? s??????, ???a????? s?µ?t?? p?s??
  f?se??, a??µ? ?a? t?? ap??? ?e??? ?????).
• ? µ??? apa?t?s? ??a t?? ap?te?esµat???t?ta t??
  µe??d?? e??a? ? d?af???p???s? t?? f?s????
  ?a?a?t???st???? t?? e?t?p???µe??? s?µat?? se
  s??s? µe ta ?a?a?t???st??? t?? pe??ß?????t??
  ?????.

?07
11
Ground Probing Radar (GPR)

• ??p?? d?p??? ?e?a?a?

?07
12
GPR efa?µ????

• ??t?p?sµ?? d??t??? ?????? ?f??e?a?
• ?d?e?s?, ap???te?s?, t??ep/??e?, f?ta????
• ??t?p?sµ?? d?as??p?s? a??a????????? ?????
• ?t?sµata, ?eµ???a, t?f??, ?a
• ?e??t? stat???? ep???e?a? ?atas?e???
• ??e???? ?p??sµ?? s????d?µat??
• ?e??t? ep?fa?e?a??? edaf???? ?e????????
  ?a?a?t???st????
• µ??????????? µe??te?
• ??t?p?sµ?? ?p??e??? ?????, de?aµe???, (µeta??????
  ?a? p?ast????), pa?a??µ?? e?e??e??? (taf? t??????
  p?s?? f?se??)

?07
13
GPR ?as???? ?????

• ?? GPR pe???aµß??e? p?µp? ?a? d??t? µ??????µ?t??,
  s??dedeµ???? µe ??a ?e???? ?e?a???. ?µ?µa t??
  e?peµp?µe??? s?µat?? p?? d?e?sd?e? µ?a (µ????)
  ap?stas? µ?sa st? ?daf??, ep?st??fe? a?a???µe??
  se ?p???d?p?te a?t??e?µe?? pa???s???e?
  d?af??et??? ??e?t???? ?a?a?t???st??? se s??s? µe
  t? pe??ß????? (?daf??).
• ??a ?a? ?? p?ast???? s????e?, ta µeta?????
  a?t??e?µe?a ?a? ta p?s?? f?s?? ????? e??a?
  d?af??et??? ap? t? ??µa, a?ta?a????? t? s?µa
  t?? GPR. ?? s?µa ep?st??fe? se ????? a?????? t??
  ß????? t?? p?s?? f?se?? f????? a????as??.

?07
14
GPR ? ap?? µ?t??s?

• ??? t? GPR d?a??te? µ?a ?e?a?a (monostatic
  arrangement), t? ß???? t?? a????as??
  p??sd?????eta? ap? t? s??s?
• d c t / 2
• ?p?? c e??a? ? ta??t?ta µ?sa st? ?daf??
• ??? t? GPR d?a??te? d?? ?e?a?e? (bistatic
  arrangement) se ap?stas? x µeta?? t???, t?te
• d sqrt (c2 t2 - x2) / 2

?07
15
GPR S??µat?sµ?? t?? e????a?

• ????e?µ???? ?a s????s??µe µ?a e????a t?? ?????
  d?as??p?s??, ?at??????? ??a e?µ??e?a
  (interpretation) ap? t?? ?e???st? t?? GPR, p??pe?
  ?a s?ed?????µe ta a?a???µe?a s?µata se ??p??a?
  µ??f?? ??f?a?? ?????.
• ?a??? t? GPR ???e?ta? ?at? µ???? µ?a? t?µ??
  d?as??p?s??,
• ???e a?a???µe?? s?µa s?ed???eta? d?p?a st?
  p??????µe??.
• ??a ta a?a???µe?a s?µata, s?ed?asµ??a
  d?p?a-d?p?a, s??µat????? µ?a saf? e????a
  (pattern)
• t?? ????a???? s?µat?? a????as??.

?07
16
GPR ?pe?ß??? ap? p???? s?µata

• ?ta? t? a?t??e?µe?? ß??s?eta? ?µp??s?e? t??
  GPR,
• ??e???eta? pe??ss?te??? ?????? ??a ?a a?a??aste?
  t? s?µa p?s? st?? ?e?a?a.
• ?a??? t? GPR ???e?ta? p??? ?a? p??? ap? t?
  a?t??e?µe??, ? ?????? ep?st??f?? t?? s?µat??
  µ???a??e? ?a? µet? a????e? p??? ?a µe?a???e?.
• ?ts?, ? e????a t?? d?ad?????? s?µ?t?? pa???e? t?
  s??µa ?pe?ß???? (hyperbola).
• ? ?µpe???? ?e???st?? a?a??????e? a?t? t? p??t?p?
  (pattern) ?? ??p??? a?t??e?µe?? st? ???t?? t??
  ?pe?ß????.

?07
17
GPR ?p??sd????st?e? p??t?p??

• ? ?pe?ß??? p?? p?????eta? ap? µ?a s????a t??
  ?p??a d?as?????µe ???eta, pa???s???e? st?? ?????
  t?? GPR saf?? s??µa.
• ? ?d?a s????a ?µ??, ?ta? t?? pa?a????????µe µe t?
  GPR ?at? µ????, de? ?a d?se? ?? e????a t?p?ta
  pe??ss?te?? ap? µ?a ep?ped? st??µ?, epe?d? t?
  ß???? t?? de? µetaß???eta?.
• ?p?p??s?eta, ?p?????? p????? d?µ?? (edaf???
  st??µata, ep?fa?e?a??? ??????t??? ?e????????
  s??µat?sµ??, st??µ? ?dat?? ?a) p?? ?a pa???a?a?
  t? ?d?? ap?t??esµa ?d????ta? se ap??sd????st?e?
  p??t?p?? (ambiguous pattern).
• ?ts?, e??a? d?s???? ?a ?a?t???af?s??µe ep?µ??e??
  d?µ?? pa?a????????ta? te? ?at? µ????. ?pa?te?ta?
  p????ste?? (e????s?a) d?as??p?s?.

?07
18
GPR ?p?d?as? t?? ?e?a?a?

• ?p?????? a??et? e?d? ?e?a??? sta s?st?µata GPR µe
  d?af??et??? ?a?a?t???st???.
• ?e?a?e? d?p???? e?p?µp??? e??e?a d?sµ?,
  ep?t??p??ta? t? s????s? µe????? ep?f??e?a?, a???
  pa?????? p?ate??? ?pe?ß???? t?? d?as??p??µe???
  a?t??e?µ????.
• Spe???e?de?? ?e?a?e? e?p?µp??? ste?? d?sµ?,
  p??sf????ta? µe?a??te?? d?a????st??? ??a??t?ta,
  a??? apa?t??ta? p????te?e? ep?fa?e?a???
  d?e?e?se?? (pe??ss?te?? e??as?a ?pa?????).

?07
19
GPR ??s? ßa?e?? µet??e?

• ?e? e??a? e????? ?a p??sd????se?? t? ß???? t??
  a?t??e?µ????, ????? ?a ??????e?? ta d???e?t????
  ?a?a?t???st??? t?? ed?f??? st?? pe????? t??
  d?as??p?s??.
• ? a?t???ß???a t?? GPR ??e? st?? a??a ta??t?ta
  186000 µ???a t? de?te???ept? (1 ft/nsec), a???
  µ?sa st? ?daf?? ? ta??t?ta a?t? e??a? s????t?s?
  t?? ?f?? t?? ed?f??? ?a? ?????? t?? edaf????
  ???as?a?.
• ? ßa?µ???µ?s? (calibration) t?? GPR (µe ß?s? t??
  µet??se?? s?µat?? se ???st? ß????) e??a?
  apa?a?t?t?, p???e?µ???? ?a e?a??e? p????f???a t??
  3?? d??stas?? (ß?????) p??a ap? t??
  ??????t???af??? p??sd????sµ? t?? d?ata?a?t????
  d?µ??

?07
20
GPR ??te ??? d???e?e?

• ?eta????? st???e?a µp??e? ?a a????e?t??? ßa??te?a
  ap? a??????? ap???µata.
• ?e???a a?t??e?µe?a µp????? ?a e?t?p?st???
  ßa??te?a ap? µ???? a?t??e?µe?a ?d?a? ?f??.
• ?d?f? ?a?a??? ?µµ?? e??a? ?,t? ?a??te?? se µ?a
  GPR d?as??p?s?.
• ? ???? ???????? e??a? ?,t? ?e???te?? µp??e? ?a
  s?? s?µße? se µ?a GPR d?as??p?s?.
• ?? ?a?a?? ?e?? de? p???a?e? p??ß??µata, a??? t?
  ?f??µ??? d?µ?????e? p???? p??ß??µata.

?07
21
GPR s????e? ?a? de???sa????
?07
22
GPR efa?µ???? ??a ????? !

• ?e???µ??? d?µ?
• ??t? ap? t?? ep?f??e?a t?? ed?f???
• ??µ??e?a
• d??d?? ?a? f???? a?ep??? !

?07
23
GPR ???t?a

• ?p?t?p?s?
• d??t???
• e?t?? p????
• ??µ??e?a
• ?a?
• ep?ßeßa??s?

?07
24
?ed?? e??????. S?st?µa GPR e??e?a? d?sµ??
?07
25
?ed?? e??????. S?st?µa GPR ste??? d?sµ??
?07
26
GPR ?af??? d?µ?
27
???a??????a
28
GPR Ge??????? ?a?a?t???st???
29
?e?aµe??? ?a? s????e?
30
????e? !!!