The Costa Rican Caribbean coast is located on the eastern coast of the nation stretching from the geographic coordinates 9° 32′ 34.8″ to 10° 56′ 24″ N and −82° 33′ 14.4″ to −83° 41′ 52.8″ W. This territory forms an elongated depression that is approximately 50 km wide extending from marine carbonate platforms of the South East to the broad alluvial plains to the North. This, forms the morphotectonic unit of the volcanic backarc, which is a result of the subduction process between the Cocos and Caribbean plates, the Central Deformed Belt of Costa Rica, the Depression Belt of Northern Panama and the subsequent erosion-accumulation of sediments of the Cordillera de Talamanca and the Central Volcanic Cordillera (Marshall, 2007Marshall, J. (2007). The geomorphology and physiographic provinces of Central America.
In Bundschuc and Alvarado(Eds.), Central America: Geology, Resources, and hazards (p. 1436). London: Taylor & Francis.[Crossref], , [Google Scholar]; Marshall, Fisher, & Gardner, 2000Marshall, J., Fisher, D. M., & Gardner, T. W. (2000). Central Costa Rica deformed belt: Kinematics of diffuse faulting across the western Panama block. Tectonics, 19(3), 468–492. DOI: 10.1029/1999TC001136[Crossref], [Web of Science ®], , [Google Scholar]).
The study area encompasses two geological regions: the Caribbean Basin and the Limón Basin. These regions are a result of the development of shallow deposits and turbidity environments generated around 65 Ma and a series of volcanic and sedimentary lithologies (Figure 1). According to Denyer and Alvarado (2007)Denyer, P., & Alvarado G. E. (2007). Mapa geológico de Costa Rica. San José: Librería Francesa. Escala 1:400 000. [Google Scholar], the different geological formations of the Costa Rican Caribbean vary on their compositions and ages from Miocene shales and sandstones (Ascari), Mio-Pliocene sandstones (Río Banano, Quebrada Chocolate, and Moín), Plio-Pleistocene conglomerates and sandstones (Eureka).