Accommodation

Aggradation

Progradation

Regression

Retrogradation

Transgressive surface

Transgressive Systems Tract

A landward movement of the shoreline indicated by a landward migration of the littoral facies in a given stratigraphic unit (Mitchum, AAPG Memoir 26)

A transgression occurs when the rate of sea level rise landward exceeds the rate of sediment input and causes an increase in accommodation, initiating the development of a transgressive surface over which the trangressive sediments of the Transgressive Systems Tract onlap and retrograde.

References
Catuneanu, Octavian (2002), Sequence stratigraphy of clastic systems: concepts, merits, and pitfalls Journal of African Earth Sciences, Volume 35, Issue 1, Pages 1-43.
Mitchum Jr., R. M., (1977), Seismic Stratigraphy and Global Changes of Sea Level: Part 11. Glossary of Terms used in Seismic Stratigraphy: Section 2. Application of Seismic Reflection Configuration to Stratigraphic Interpretation, Memoir 26 Pages 205 - 212.