Yes, geologists can use data from two seismograph stations to estimate the earthquake's epicenter, but they need at least three stations to accurately locate the epicenter. Here's why:

* Two stations provide distance information: Each seismograph records the arrival time of the P-wave and S-wave from the earthquake. The difference in arrival times (the S-P interval) indicates the distance between the station and the epicenter. With two stations, you have two distances, which defines a circle around each station. The epicenter would lie somewhere on the intersection of those two circles.

* Three stations pinpoint the epicenter: The intersection of two circles creates an ambiguous location with two possible points. Adding a third seismograph station and its distance measurement creates a third circle. The point where all three circles intersect is the unique and accurate location of the earthquake epicenter.

Therefore, while two stations can provide a rough estimate, three stations are necessary for precise epicenter determination.