GATE-2018 (24) :Wyllie – Time average equation

106.Gravity anomaly values of 1.2,2,4 and 3.6 in m gals are located at distance coordinates 20,24 and 28 km, respectively ,along a gravity profile across a faulted basement of limited throw. The depth to the basement  (in km) is

A)    2

B)    2 √2

C)    2 √3

D)   4

Solution:

The relation between depth and half-width for a fault is given that,

$Z_c=1.0*X_{1/2}$

From figure the half-width of the fault is $X_{1/2}$ = 24-20 = 4 km

$Z_c=1.0*4$

$Z_c=4 km$

Reference: Gravity and Magnetic Exploration Principles, Practices, and Applications by William J. Hinze, Ralph R.B. Von Frese and Afif H.Saad