Link to USGS home page.
St. Petersburg Coastal and Marine Science Center
Coastal and Marine Geology Program > St. Petersburg Coastal and Marine Science Center > Coasts of Colombia

Coasts of Colombia

Coasts of Colombia
Pacific Coast:
Introduction
Serranía del Baudó (Baudó Range)
Cabo Corrientes-
Togoromá
San Juan River Delta
Málaga Bay - Buenaventura Bay
Buenaventura Bay - Guapi
Patía River Delta
Tumaco Bay
Mira River Delta
Gorgona Island
Malpelo Island
References
Caribbean Coast:
Introduction
Guajira Peninsula Coast
Sierra Nevada de Santa Marta Coast
Magdalena River delta and Santa Marta lagoon complex
Barranquilla - Cartagena coast
Southern Caribbean coast
Gulf of Urabá
References
Project Contact:
Robert Morton

Caribbean Coast: Barranquilla - Cartagena coast

The Barranquilla-Cartagena coastline (Fig. 2) has an approximate length of 100 km and a general S 45º W orientation, controlled by the structural trends of the Tertiary rocks (Fig. 10). El Dique Channel and Cartagena Bay occupy tectonic depressions, whereas Tierrabomba Island and the Barú Peninsula are uplifted sectors capped by Plio-Pleistocene reefs. Because of the artificial connection between El Dique channel and the Magdalena River, El Dique delta is rapidly accreting, with sediments filling the bays of Barbacoas and Cartagena (Vernette 1985).

Landsat image of the Barranquilla - Cartagena area, showing its main physiographic elements.
Figure 10. Landsat image of the Barranquilla (B)-Cartagena area, showing its main physiographic elements. Reproduced by permission of Invemar.

Coastal formations between Barranquilla and Galerazamba are associated with the San Jacinto Belt, a deformed, Middle Eocene sequence of pelagic, hemipelagic and turbiditic rocks (Duque-Caro 1984). The littoral relief of these formations is typically represented by cliffs, up to 100 m high, and hills dissected by minor Quaternary alluvial valleys.

West of Bocas de Ceniza (Fig. 11) between Barranquilla and Galerazamba (Fig. 10), the coastline shows a serrated pattern consisting of steep cliffs (5 to 40 m high) cut into consolidated Tertiary sediments of the San Jacinto Belt (Fig. 12). Most cliffs are fronted by narrow beaches supplied by erosion of Tertiary formations and sand eroded from the Magdalena River delta.

Landsat image showing the coastal configuration between Bocas de Ceniza and El Morro Point.
Figure 11. Landsat image showing the coastal configuration between Bocas de Ceniza and El Morro Point. Construction of the Bocas de Ceniza jetties in 1938 caused complete erosion of an extensive offshore bar system that protected the coastline between the mouth of the Magdalena River and El Morro Point. Shore recession west of the river's mouth has been several kilometers. Reproduced by permission of Invemar.

Steep cliffs cut into Tertiary sandstones and mudstones and fronted by narrow beaches at El Morro Point.
Figure 12. Steep cliffs cut into Tertiary sandstones and mudstones and fronted by narrow beaches at El Morro Point. View to the South. Photo by I. Correa.

Between Galerazamba and Punta Canoas, the coastline is dominated by depositional features fronting inactive cliffs, mainly sandy spits and bars that modulate the coastal indentations. Historical information for this area (Ramírez 1959, Raasveldt and Tomic 1958, Correa 1990, Morton and Correa 2004) shows large shoreline changes along this segment of coast, including erosion of a 12-km-long, EW-oriented spit reported in 1794 (Fig. 13) and formation of the 7 km2 Isla Cascajo tombolo (Fig. 14).

Ancient chart by Spanish Brigadier Francisco Fidalgo, showing the 1793 coastline between Galerazamba and Cartagena.
Figure 13. Ancient chart by Spanish Brigadier Francisco Fidalgo, showing the 1793 coastline between Galerazamba and Cartagena. The former Galerazamba spit (12 km long) at that time was attached to rocky stacks and mud volcanoes. IC shows the location of Cascajo Island, currently attached to the mainland by a 7-km2 tombolo developed between Morro de La Venta (MV) and Punta de Piedras (PP). Shoreline changes along this sector are the largest natural historical migrations of the Caribbean coast of Colombia. The Galerazamba area is famous for the common occurrence of explosive offshore mud volcanoes. Reproduced by permission of Universidad Eafit.

Aerial view of the northwestern extreme of the Isla Cascajo tombolo showing extensive beach-ridge progradation.
Figure 14. Aerial view of the northwestern extreme of the Isla Cascajo tombolo showing extensive beach-ridge progradation. PA indicates the position of the cliff coastline mapped by Brigadier Fidalgo in 1793. Photo by I. Correa.

From Punta Canoas Peninsula (Fig. 10) to the Bay of Cartagena, the coastline is dominated by detrital erosional beaches (Figs. 15 and 16) and bars that extend to the northern side of Cartagena Bay. There extensive land reclamation has been used to enlarge the city of Cartagena (Fig. 17).

Cobble-block beach and vertical cliffs cut into Tertiary mudstones and sandstones, southern part of the Punta Canoas Peninsula.
Figure 15. Cobble-block beach and vertical cliffs cut into Tertiary mudstones and sandstones, southern part of the Punta Canoas Peninsula. Photo by I. Correa.

View to the north of the beaches of Manzanillo, between Punta Canoas and Cartagena.
Figure 16. View to the north of the beaches of Manzanillo, between Punta Canoas (up left) and Cartagena. The beaches near Manzanillo are retreating at rates of about 1 m/yr since the last decade because of spit accretion to the north and local shingle and sand extraction. Photo by I. Correa.

Aerial view of the southern area of Cartagena.
Figure 17. Aerial view of the southern area of Cartagena. Cartagena's beaches are eroding despite the hard engineering structures built to protect them. Reproduced by permission of Cartagena Office of Tourism.

Tierrabomba Island and the Barú Península are composed of Plio-Pleistocene mudstones and limestones that show evidence of recent relative sea-level changes, including wave-cut platforms (Fig. 18), elevated caves, and stacks. The features are as much as 5 m above present sea level and have been dated as late Holocene (Vernette 1985). Steep erosional cliffs and narrow calcareous pocket beaches dominate the outer coastlines of Tierrabomba Island and the Barú Peninsula. Extensive mangrove swamps are found along the margins of the Cartagena and Barbacoas Bays.

Emerged wave-cut terrace at Tierrabomba Island, west side of Cartagena Bay.
Figure 18. Emerged wave-cut terrace at Tierrabomba Island, west side of Cartagena Bay. Photo by R. Morton.

Coastal and Marine Geology Program > St. Petersburg Coastal and Marine Science Center > Coasts of Colombia

FirstGov button  Take Pride in America button