Chucal Formation

{{one source|date=January 2023}}

{{Short description|Geological formation in northern Chile}}

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| name = Chucal Formation

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| type = Geological formation

| period = Miocene

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| region = Arica y Parinacota Region

| country = Chile

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| overlies = Lupica Formation

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Chucal Formation ({{langx|es|Formación Chucal}}) is a volcano-sedimentary geological formation in the Andes of Arica y Parinacota Region in northernmost Chile. Sediments of the formation deposited sometime during the Miocene epoch (23 to 5 million years ago) and represent fluvial and lacustrine environments.{{Cite journal |title=Rapid tectonic and paleogeographic evolution associated with the development of the Chucal anticline and the Chucal-Lauca Basin in the Altiplano of Arica, northern Chile|journal=Journal of South American Earth Sciences |last=Charrier |first=Reynaldo |issue=1 |volume=19 |pages=35-54 |last2=Chávez |first2=Álvaro N. |year=2005 |last3=Elgueta |first3=Sara |last4=Hérail |first4=Gérard |last5=Flynn |first5=John J. |last6=Croft |first6=Darin A. |last7=Wyss |first7=André R. |last8=Riquelme |first8=Rodrigo |last9=García |first9=Marcelo |author-link=Reynaldo Charrier}} It overlies Lupica Formation.