x(m) ref1(ms) ref2(ms) ref3(ms) ref4 (ms) 235,36 477,26 723,17 966,07 100 150 200 250 -200 -190 476,55 722,84 965,89 -150 -100 233,08 -250 -50 50 -200 -180 230,87 475,86 722,53 965,72 -170 228,76 475,21 722,24 965,56 -160 226,75 474,59 721,96 965,41 -150 224,85 474,01 721,69 965,27 -140 223,06 473,47 721,45 965,13 -130 221,37 472,96 721,22 965,01 200 -120 219,8 472,5 721,01 964,89 -110 218,35 472,06 720,81 964,79 -100 217,01 471,67 720,63 964,69 90 215,8 471,31 720,47 964,6 -80 214,7 470,99 720,33 964,53 -70 213,73 470,71 720,2 964,46 60 212,89 470,47 720,09 964,4 400 -50 212,17 470,26 720 964,35 -40 211,58 470,09 719,92 964,3 HHH HHHHH 30 211,12 469,96 719,86 964,27 ref 1(ms) 20 210,79 469,86 719,82 964,25 (s ) -10 210,59 469,8 719,79 964,23 Serie "ref2(ms)" Punkt "130" 0 210,53 469,79 719,79 964,23 600 (130, 472,96) (s) 10 210,59 469,8 719,79 964,23 * ref4 (ms) 20 210,79 469,86 719,82 964,25 30 211,12 469,95 719,86 964,27 40 211,57 470,09 719,92 964,3 50 212,16 470,26 720 964,35 60 212,88 470,46 720,09 964,4 800 70 213,72 470,71 720,2 964,46 80 214,69 470,99 720,3 964,52 90 215,78 471,31 720,47 964,6 100 217 471,67 720,63 964,69 110 218,33 472,06 720,81 964,79 120 219,79 472,49 721,01 964,89 130 221,36 472,96 721,22 965,01 1000 140 223,04 473,47 721,45 965,13 150 224,83 474,01 721,69 965,27 160 226,73 474,59 721,95 965,41 170 228,74 475,2 722,23 965,56 180 230,85 475,85 722,53 965,72 190 233,06 476,54 722,84 965,89 1200 200 235,36 477,26 723,17 966,07 200 235,36 477,26 723,17 966,071. The figure shows a shot gather that was recorded in a location where the subsurface consists of a series of horizontal layers. The travel times are listed on the attached table. You may answer the following by using graph paper or Excel. A copy of the travel times will be distributed by e-mail. (a) For the first reflection plot a graph of normal moveout (NMO) as a function of offset squared (x*). Remember that the equation for normal moveout is an approximation that is valid for x versus x> and compute the thickness (z;) and velocity (v,) of the first layer. (d) For reflections 2,3 and 4, list the travel times at zero offset (t,, t; and t,). (e) Plot normal moveout as a function of x? for reflections 2,3 and 4. Using the normal moveout equation n ' rms,n compute the r.m.s. velocities (V. 2 Vims, 3 and V., o). Be careful to only use travel times for which the equation is valid.