We show that the terrestrial land and seafloor contain no volcano-tectonic mega landforms expressed in relief that could be similar in size to those identified on Mars, and could have analogous structure and origin to the giant landforms whose volumes of constituent rocks are (1-2.4) x 106 km3 (Alba Patera, Olympus Mons, Arsia Mons, Ascraeus Mons, Pavonis Mons, and Elysium Mons). No fragments or traces of similar features have ever been unambiguously identified and described in geological rock sequences, not only in Mesozoic and Cenozoic rock sequences, but also in those dating back to Paleozoic time. The same applies to the older epochs on Earth. Now the topographic constituent components of Martian mega landforms have the appearance of very magnified copies of well-known and repeatedly described terrestrial volcanic edifices, viz., dominantly shield-like and lava volcanoes, lava domes, as well as calderas of various types. However, the edifices of the above types of volcanoes are not identical with their Martian counterparts as to morphology, being shorter in height and having steeper slopes. The calderas are smaller by factors of multiple times. The Martian volcanic landforms are much older. There is a unique edifice, namely, Olympus Mons, a mega land-form that stands in a large glacier sheet and for whose origin glacial processes are also responsible. It is classified as belonging to the type of giant tuyas. Its mini analogues are glacial subaerial tuyas of different ages and parameters that have been subjected to glaciation in volcanic areas on Earth.

This study revealed that the giant cirque of Bakening Volcano had been produced by its eruption ca. 8000-8500 carbon-14 year ago. The eruption is supposed to have been heralded by a large earthquake (M > 7) resulting in the collapse and slide of the SE sector of the cone. The landslide unroofed the hydrothermal system and triggered an explosion which was followed by an ash-and-block pyroclastic flow. A rockslide avalanche rolled down into the valley of the Srednyaya Avacha River and travelled as far as 10-11 km along it. The avalanche deposited its debris material over an area of 18-20 km2 measuring 0.4-0.5 km3 in volume. These deposits dammed the river, produced two lakes (Bezymyannoe and Verkhneavacha), and gave birth to a large lahar which traveled along the valley much farther.

Постоянные наблюдения за сейсмическим режимом вулкана Шивелуч позволили установить, что гигантское извержение предвещалось роем слабых вулканических землетрясений. Изучение землетрясений, предваряющих и сопровождающих извержения, дало богатый материал позволяющий прослеживать ход вулканической деятельности.