Geophysical processes and biosphere: article

Аnnotation: Ocean level fluctuations relative to continents are caused by both physical processes related to water volume change and tectonic processes related to changes in the bottom topography. Currently, the main tectonic cause is considered to be the occurrence of mid-ocean ridges and the change in the rate of expansion of the ocean floor with the corresponding rise or fall of the bottom. The specific role of continental drift is not taken into account, or they are given a passive role. The work demonstrates the important role of continents in long-term changes in ocean level. The numerical model shows how the continents influence the tectonic activity of the mantle, how they float on the mantle with uneven relief, which cause relative changes in ocean level. While the continent is above the ascending mantle stream, it is raised, and the ocean level relative to the continent decreases. After the split of the supercontinent, the continents diverge and the ridge, which was previously covered by continents, is in the ocean. Being close to subduction zones, the continents are lowered, leading to increases in relative sea level. The model also shows that the continents do not move strictly horizontally along the mantle, but, like floating ships, change their slope depending on the mantle relief.