Cura-Mallín Group

Cura-Mallín Group
Stratigraphic range: Upper OligoceneMiddle Miocene
Colhuehuapian-Laventan (SALMA)
TypeGeological group
Unit ofCura-Mallín Basin
 Neuquén Basin
Sub-unitsVarious schemes, see text
UnderliesCajón Negro Formation
Trapa Trapa Formation
OverliesCretaceous granitoids
Jurassic sediments
Thickness>1,800 m (5,900 ft)
Lithology
PrimarySandstone, siltstone, shale, breccia, andesite lava
OtherGrainstone
Location
Coordinates37°42′S 71°12′W / 37.7°S 71.2°W / -37.7; -71.2
Approximate paleocoordinates38°18′S 66°24′W / 38.3°S 66.4°W / -38.3; -66.4
RegionAraucanía & Bío Bío Regions
Neuquén Province
CountryChile
Argentina
Type section
Named forMallín
Cura-Mallín Group (Chile)

Cura-Mallín Group (Spanish: Grupo Cura-Mallín) is a heterogeneous group of volcano-sedimentary formations of Oligocene-Miocene age, Colhuehuapian to Laventan in the SALMA classification, in south-central Chile and nearby parts of Argentina. The sediments belonging to the group were deposited in a lacustrine environment and alongside rivers in an intra-arc basin. Southeast of Laguna del Laja Cura-Mallín Group has a thickness of more than 1,800 metres (5,900 ft). The sediments making up the group deposited in an interval between 22 and 8 million years ago.

The outcrops of Cura-Mallín Group are found along a north–south elongate area. The group is considered an equivalent of Abanico Formation, either as a southern extension or as a lateral equivalent of that formation.