Question

station b
arrival time
p - wave
4:30:070fec
arrival time
s - wave
4:30:270fec
s - p
lag time (s)
23 seconds
distance from
epicenter (km)
(kilometers)
__________

Explanation:

Step1: Recall the S - P lag - distance relationship

In seismology, the relationship between the S - P lag time ($\Delta t$) and the distance ($d$) from the epicenter is often approximated by the formula $d = v\times\Delta t$, where $v$ is the average velocity difference between S - waves and P - waves. A common approximation is that for each second of S - P lag time, the distance from the epicenter is approximately 8 kilometers (this is a simplified approximation used in basic seismology education). So if the S - P lag time ($\Delta t$) is 23 seconds.

Step2: Calculate the distance

Using the formula $d=\ 8\ km/s\times\Delta t$, substitute $\Delta t = 23\ s$.
$d = 8\times23$
$d=184$ kilometers.

Answer:

184 kilometers