Giant Martian Volcano-Tectonic Mega Morphostructures and Their Likely Terrestrial Mini Analogues

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) × 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 landform 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.