Variance and spread of the average sol utton for the Abitibi data. l. " â¢â¢ ... _ ..... coordinate r whlch ls the distance along the raye Equation. (2.5) can be rewr 1 tten ...
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by
RaUl }del Valle G..
B.Sc.
A thesis submitted in partial fulfilment of the requireme~ts for t~ cte9f;e of Master of Science in applied Geophyslcs
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Faculty of Graduate Studles .and Research ,
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Departltent of Geological Sciences MCGJLll University Montreal. Canada
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Rau~ del Valle G. and, G~ophyslcs Research Laboratory
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Februa ry 1986
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A technique 1. pre •• nted for the Interpretation of sèiBmlc
• refractlon
" one-dl.en.lona~
data ualng
Th~
veloclty structures.
forward proble. la solved by aayaptotlc ray t~eory and la "lncorporated Into an inverai~ proc.ss. The efflc lency
. f the Inver.e .ethod 0
j
a reduced both by the
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non-unlquene.s due to the apars1ty oL t'he refractlon data anç1 by the non-l1neu paulleterlzatlon Involvtrd. Becauae ln general
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th. final solution dependa on the
Initial 'gues's of lIodel
paulletera, ve fl'fst explore the .range of possible sO'lutlona by using
the Monte Carlo lIethod. An overparalleterlzatlon of
,"
lIodel. i8 8uggested in order to Inveatigate,
1D0at of the
1'"
rhY8iCal an~
geolletrica1 chara~teriatic8 of the problell.
Afterwards, ve use the full power of the llnearized inverse theory to aas.sa and optia1z. the Monte Carlo solution by \
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evaluet1ng the re8olutlon and variance of the .-ode,1 panatetera. 1
. Siaple syntheUc aodets are
u~ed
to atudy. the convergence
and atatlstlcal propertles of the aolutlons. The lIethod ~as applled to refraction data froll the Abitibi greenatone belt ('
uslng only layered lIodel,. Bovever,-an extension of the '.ethod 1
ta aode1a vlth lateral gra4i.nts or structures 18 readlly
bl~ck-llke
velocity
posaible.
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