TortonianMessinian
The Tortonian Messinian refers to a stage in the geologic timescale, specifically within the late Miocene epoch. It spans from approximately 11.608 to 5.333 million years ago. This period is most famously characterized by the Messinian Salinity Crisis, a geological event that saw the Mediterranean Sea largely or completely desiccate. During the Tortonian, sea levels were generally higher globally compared to the subsequent Messinian, but the isolation and evaporation of the Mediterranean began in earnest towards the end of this stage. The deposition of thick evaporite sequences, such as salt and gypsum, in the Mediterranean basin provides substantial evidence for this crisis. The Tortonian stage also saw significant evolutionary developments in various terrestrial and marine ecosystems. For instance, many mammalian lineages continued to diversify. The geological and paleontological record from this time offers crucial insights into Earth's climate, sea-level fluctuations, and the resilience of life in the face of dramatic environmental changes. The transition from the Tortonian to the preceding Serravallian and succeeding Zanclean stages is defined by specific biostratigraphic markers, primarily the last appearance of certain planktonic foraminifera.