The Relationship between Magnitudes <i>MLH</i> and <i>M</i><sub>W</sub> for the Kuril-Okhotsk Region and its Use for Transit Conversions to Other Magnitudes

In order to unify the earthquake catalogue of the Kuril-Okhotsk region, the two-segment linear relationship was obtained between the surface wave magnitude MLH of the Sakhalin branch of the GS RAS and the moment magnitude MW of the GCMT and NIED agencies. Comparison with similar formulas based on different catalogs shows that for strong MLH = 6.5–8.1 earthquakes, there is a slight ~ 0.1 excess of the regional magnitude of MLH over the MS. In the interval MLH = 4.0–6.5, the regional magnitude MLH exceeds MS values by 0.2–0.4. The relationships between MLH and ML of the Kamchatka branch of the GS RAS in the region of the middle-northern Kuril Islands, MLH and Mj of the JMA agency for the southern part of the region were obtained. By transit recalculation using the relation MLH (MW), it was possible to repeat the directly obtained dependences with good accuracy. The best result is achieved by taking into account the differences in MW obtained by different agencies.