Transgressive lag
Synonym
Transgressive gravels, Transgressive sands, Ravinement surface, Ravinement erosion surface, Wave-ravinement surface
Depth of water
High tide - Ebb tide
Circumstances
Residual sediments remained on the erosional surface of the lower level strata which is formed by wave erosion in the stage of transgression.
Sedimentary facies (Sediments)
Poorly-sorted gravels and sands. Beach gravels, or sands of tidal channel. Relatively dominated in coarse sediments such as shells, calcareous nodules, and siliceous gravels.
Sedimentary facies (Structures)
Sediments of ravinement surface overlies with an erosion surface on the basement. Less than 50 cm thick.
Sedimentary systems
Components of shallow marine systems
- Beach ridge
- Interbarnal lowland (Ridge)
- Eolian dune
- Interdune lowland
- Salt marsh
- Backshore
- Foreshore
- Tidal flat
- Tidal channel
- Beach rock
- Lagoon
- Flood tidal delta
- Washover fan
- Upper shoreface
- Barrier island
- Sand spit, Longshore bar
- Ebb tidal delta
- Lower shoreface
- Inner shelf
- Outer shelf
- Sand wave
- Sand ridge
- Tsunami
- Transgressive lag