San Sebastián Bay is located in the northern coast of Argentina's Tierra del Fuego Province. The bay is partly enclosed by the 17 km-long El Páramo spit that protrudes from the north. The spit is made of

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is usually defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural ...

and

gravel Gravel () is a loose aggregation of rock fragments. Gravel occurs naturally on Earth as a result of sedimentation, sedimentary and erosion, erosive geological processes; it is also produced in large quantities commercially as crushed stone. Gr ...

. There has been a trend of falling relative sea level over the last 7,000 years. Tides in the bay are large.

References

Bays of Argentina Isla Grande de Tierra del Fuego {{TierradelFuegoAR-geo-stub