Correlation between the Points of Different Seismic Intensity Scales

The seismic intensity scale is one of the oldest instruments for determining the extent of seismic vibrations. Being initially a descriptive characteristic of seismic impact, intensity has long required only more detailed, thorough consideration and recording of the consequences and manifestations of various primary and secondary effects in earthquakes in order to increase its accuracy. The indicators were changes in the natural environment, the reactions of humans and animals, and the results of the impacts of seismic events on various engineering structures. Obviously, the latter research objects listed in this series have the most variable characteristics over time. The emergence of new building structures and materials had to be reflected in the seismic intensity scales. This is encouraging changes in the scales used and the development of new scales. At the same time, there is the problem of the correlation of earthquake intensity estimates over different seismic intensity scales. The article considers the problem of quantitative assessment of differences in intensity determination according to the MCS, MM, MSK-64, and EMS-98 scales, as well as two new national Russian standards, GOST R 57546–2017 and GOST 34511−2018. Comparison is carried out separately according to the macroseismic and instrumental parts of scales. Macroseismic descriptions of individual points (gradations) is analyzed using indicator object, people, objects, buildings and structures, and natural phenomena. Each indicator is considered separately. For the MCS, MM, and MSK-64 scales, as well as GOST R 57546–2017 and GOST 34511−2018, their instrumental parts were compared. Based on these studies, it was concluded that the macroseismic parts of these scales coincide, with the exception of low estimates of the dimensions of fissures in soils on the MSK-64 scale. Average differences in the descriptions of damage to buildings and structures do not exceed 0.1 points. Significant differences exist in the instrumental parts of MM, MSK-64, and GOST R 57546–2017.