KALAMAZOO, Mich. (AP) — A geological fault line has been revealed in southwest Kalamazoo County following a small earthquake in the area over the weekend.

Kazuya Fujita, a geosciences professor at Michigan State University, wrote a paper 20 years ago suggesting the existence of the geological fault line due to variations in the magnetic field. Fujita says it appears the fault that caused the 4.2-magintude temblor Saturday is part of the same fault involved in a 1947 quake in Coldwater.

Chris Schmidt, a geoscientist for Western Michigan University, tells the Kalamazoo Gazette the May 2nd quake "matches almost perfectly" with Fujita's theory.

Both scientists say the quake, whose epicenter was in a rural farming community about 12 miles southeast of Kalamazoo, was the result of natural forces.