Lg propagates efficiently with predominant periods of about 1 to 1 1/2 s across the stable regions of Asia: the Indian shield, the Eurasian platform, the Tarim basin, and (less efficiently) eastern China. This suggests that the structure is relatively homogeneous and Q must be high in the crust in these regions. For paths across the Tien Shan, where the crust is abnormally thick, Lg is observed with somewhat less sharp arrivals, but nevertheless, frequencies are high, and amplitudes large. For paths along the Tien Shan, signals are weaker, and arrivals are still less sharp. Lg was not observed for paths crossing the Tibetan Plateau. We infer that the change in crustal structure on the margins of the Tibetan Plateau and at the Tien Shan may disrupt the wave guide for Lg and may scatter energy out of the relatively homogeneous wave guide of the more stable crust. Alternatively or in addition, Lg may not propagate across the Tibetan Plateau because of an unusual velocity structure or because of high attenuation in the crust.

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Results of monitoring seismicity in the main regions and territories of Russia are given, i.e., Western and East Caucasus, East European Platform, Urals and West Siberia, the Arctic Basin, Altai and Sayan Mountains, Lake Baikal, Cis- and TransBaikal regions, the Amur region and the Primorye, Sakhalin Island, Kuril-Okhotsk Region, Yakutia, North-East Region of Russia and Chukotka, Kamchatka and Komandor Islands in the year 2018. Catalogs of the most significant earthquakes are provided for each region considered with parameters of their hypocenters and magnitudes obtained from the instrumental observation. Manifestation of macroseismic effect from the majority of the notable earthquakes (with I ≥ 2 points on MSK-64 scale) that occurred in the territory of Russia is analyzed. Work of is intended for seismologists, geophysicists, geologists and specialists in earthquake-resistive construction.