Subsidence in geology describes the progressive sinking of a surface, generally of the lithosphere, either due to the relative movement of tectonic plates that include both their convergence and their divergence or, on a smaller scale, by the settlement of the land in sedimentary basins (often accelerated by human action, as is the case of oil basins or the extraction of groundwater[1]​) or by the cessation of volcanic activity in small areas around to the volcanoes themselves, as is the case with atolls. In the case of subsidence, sea level, logically, rises. The opposite of subsidence is uplift "Uplift (geology)"), which results in an increase in the altitude of the solid surface of our planet and, consequently, in a decrease in sea level.[note 1]​.

Convergence of tectonic plates is called the collision between two plates that move in opposite directions and that gives rise to the rise of one plate (generally the continental plate) and the sinking into the mantle of the other plate (generally the oceanic plate). The subsidence is evidently formed in the underwater plate, forming what is known as the oceanic trench and in this case, the subsidence or sinking is called subduction. The South American trench on the coast of the Pacific Ocean (Peru-Chile Trench) is a good example, with a depth greater than 8,000 m below sea level. The deepest of the ocean trenches is that of the Mariana Islands, just over 11,000 meters deep.