Caldera Basin (Spanish: Cuenca de Caldera) is a sedimentary basin located in the coast of northern Chile west of Copiapó. The basin has a fill of marine sediments of Late Cenozoic age. With a north–south extension of 43 kilometres (27 mi) and an east–west width of 20 kilometres (12 mi) the basin occupies an area between the coast and the Chilean Coast Range and between the port of Caldera and the mouth of Copiapó River. The sedimentary fill rests on metamorphic rocks of Paleozoic age and on plutonic rocks of Mesozoic age.

Stratigraphy

The following units make up the sedimentary fill
NameAgeLithologiesDepositional environment
Caldera BedsPleistocene
Bahía Inglesa FormationQuebrada BlancaLate MioceneConglomerate, sandstone, biocalciruditeShoreface, outer shelf, tsunami
Rocas NegrasCalcirudite, biocalciareniteShoreface
Mina FosforitaSandstone, siltstone, shaleUppermost continental slope, shoreface
ChorrillosClast-supported conglomerateSubmarine canyon debris flow fill, formed possibly by a tsunami
La HigeraShale with gypsum veins, sandstone, siltstone, diatomaceous clayOuter shelf or uppermost continental slope
Cerro BallenaSilty sandstoneSupratidal flat
Punta TotoralBiocalcarenite, biocalcirudite, matrix-supported conglomerateRapid sea-level oscillations
Puerto ViejoSandstone, siltstone, claystone, shale, microcoquinaShoreface, marine transgression
El PimientoBiocalcarenite, quartzareniteShoreface
Angostura FormationEarly to Mid-MioceneMatrix-supported conglomerateHigh-energy river mouth

Further reading

  • Achurra, L.E.; Lacassie, J.P.; Le Roux, J.P.; Marquadt, C.; Belmar, M.; Ruiz Del Solar, J.; Ishman, S.E. (2009), (PDF), Sedimentary Geology, 217 (1): 128–139, Bibcode:, doi:, archived from (PDF) on 2017-10-26
  • Achurra, L.; Marquadt, C.; Lacassie, J.P.; Le Roux, J.P. (2003), (PDF), X Congreso Geológico Chileno, pp. 1–10, archived from (PDF) on 2017-10-26
  • Acosta Hospitaleche, Carolina; Canto, Jhoann (2005), (PDF), Revista Chilena de Historia Natural, 78: 489–495
  • Chávez Hoffmeister, Martín Felipe (2008), (PDF), Universidad Austral de Chile, pp. 1–165
  • Chávez, Martín F (2007), (PDF), Revista Chilena de Historia Natural, 80 (2): 255–259, doi:
  • Chávez, Martín (2007), , Boletín de la Sociedad Geológica del Perú, 102: 101–107
  • Le Roux, Jacobus P.; Achurra, Luciano; Henríquez, Álvaro; Carreño, Catalina; Rivera, Huber (2015), (PDF), XIV Congreso Geológico Chileno, pp. 821–824, archived from (PDF) on 2017-10-26
  • Oyanadel Urbina, Pablo; Carrillo Briceño, Jorge; Villafaña, Jaime; Castelleto, Victor; Varas, Cristian; Alballay, Alex; Rivadeneira, Marcelo (2015), (PDF), XIV Congreso Geológico Chileno, pp. 1–4, archived from (PDF) on 2017-10-26
  • Staig, Felipe; Hernández, Sebastián; López, Patricio; Villafaña, Jaime A.; Varas, Cristian; Soto, Luis Patricio; Carrillo Briceño, Jorge D. (2015), , Revista Brasileira de Paleontologia, 18 (2): 261–272, doi:
  • Suárez, Mario E (2011), (PDF), Comuna de Caldera Región de Atacama, pp. 1–29
  • Valenzuela Toro, Ana; Gutstein, Carolina S., (PDF), pp. 770–772, archived from (PDF) on 2017-10-26