An analytical review of recent papers on the themes “Fluidolites”, “Clay diapirism”, “Clay injection and extrusion” is offered. These phenomena correspond fundamentally to fluid displacement (water, gas, clay and organic matter), whereas massive sedimentary uplift corresponds to large vertical displacement of stratified solid levels but the deeper cause of the latter could partly be the intrusion of mud plugs. The dynamic phenomena controlled by the development of overpressure at depth, contributing to sedimentary mobilization are reported. These processes include clay mineral dewatering, thermogenic degradation of organic matter and deep high-temperature leaching of terrigenous sediments with formation of mud volcanoes.