Chap. 9] 



(8) 



(9) 



H.= 



SEISMIC METHODS 

 Xi3u[l — sin (/3 — (p)] — i/i[cos (a + v?) + cos (/3 — <p)] 



531 



H. = 



hid = 



2 sin ii cos 12 cos rj/ 

 2 sin t2 cos ii cos i^ = 2 0.6 -0.745 -0.985 = 0.881 

 cos {a-\- <p) + cos (13 - <p) = 0.961 + 0.857 = 1.818 

 1 



0.881 



[1174(1 - 0.2756) - 250.1.818] = 450 m 



a^i3d[l — sin {a + <p)] — /tid[cos (a + «p) + cos (]8 — <p)] 

 2 sin ii cos i'z cos ^ 



[677(1 - 0.515) - 57.5. 1.818] = 252 m 



0.881 



Fig. 9-67. Travel-time curves for two layers of opposite dip direction (after O. v. 



Schmidt). 



For the second example, Fig. 9-67 furnishes the following data: 

 (Fig. 9-67, AB = 2500 m) 

 Up-Dip Profile Down-Dip Profile 



Vi = 1800 m -sec~^ Vi =1800m.sec~^ 



Viu = 3230 m • sec 

 V3„ = 4370 m - sec" 



Vzd = 2805 m • sec ^ 

 Vzd = 4710 m-sec"^ 



