Fig. 4From: Periodic upward migration model for intermediate-depth earthquakes in Vrancea, RomaniaRelationship between years of occurrence and focal depths of earthquakes (Table 1). The large solid circles, small solid triangles, and open triangles represent M ≥ 7.5,7.3 ≤ M < 7.5, and 7.0 ≤ M < 7.3 earthquakes, respectively. F: Fake M 7 earthquakes (refer text and Table 1).Back to article page