Lautaro Formation

Lautaro Formation
Stratigraphic range: ToarcianAalenian,
~
Strata of the Lautaro Formation outcropping at the Tranque Lautaro
TypeGeological formation
UnderliesQuebrada Monardes Formation
OverliesLa Ternera Formation
Thickness~2,600 m (8,500 ft)
Lithology
PrimaryLimestone
OtherSandstone
Location
RegionAtacama Region
CountryChile
ExtentLautaro Basin
Type section
Named forLautaro

The Lautaro Formation is sedimentary and fossiliferous geological formation that largely crops out near Copiapó (Atacama Region), Chile. It is dated back to the Jurassic period (Toarcian through Aalenian stages). The lithology of the formation comprises limestone and sandstone, formed in marine settings. The Lautaro Formation preserves a marine fossil record, representing molluscs (bivalves, gastropods) and marine reptiles (metriorhynchids).

The strata of the Lautaro Formation and its basin of deposition (the Lautaro Basin) have been subject to intense tectonic movement during the Mesozoic, producing large-scale stratigraphic discontinuity and tectonic inversion.