Salta Basin or Salta Rift Basin is a

sedimentary basin Sedimentary basins are region-scale depressions of the Earth's crust where subsidence has occurred and a thick sequence of sediments have accumulated to form a large three-dimensional body of sedimentary rock They form when long-term subsidence ...

located in the

Argentine Northwest The Argentine Northwest (, NOA) is a geographic and historical region of Argentina comprising the provinces of Catamarca Province, Catamarca, Jujuy Province, Jujuy, La Rioja Province, Argentina, La Rioja, Salta Province, Salta, Santiago del Estero ...

. The basin started to accumulate sediments in the

Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...

( Neocomian) and at present it has sedimentary deposits reaching thicknesses of . The basin contains seven sub-basins: Tres Cruces, Lomas de Olmedo, Metán, Alemanía, Salfity, El Rey, Sey and Brealito. The basin environment has variously been described as a " foreland

rift In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics. Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-graben ...

" and an "intra-continental rift". The basin developed under conditions of

extensional tectonics Extensional tectonics is concerned with the structures formed by, and the Tectonics, tectonic processes associated with, the stretching of a planetary body's Crust (geology), crust or lithosphere. Deformation styles The types of structure and the ...

and rift-associated

volcanism Volcanism, vulcanism, volcanicity, or volcanic activity is the phenomenon where solids, liquids, gases, and their mixtures erupt to the surface of a solid-surface astronomical body such as a planet or a moon. It is caused by the presence of a he ...

Description

The basin basement is composed of rocks belonging to the

Puncoviscana Formation Puncoviscana Formation () is a formation (geology), formation of sedimentary rock, sedimentary and metamorphic rock, metasedimentary rocks Ediacaran, Late Ediacaran and Cambrian, Lower Cambrian age, estimated at between 700 and 535 Ma, that crop o ...

.Grier et al., 1991 The volcanism that began in the

Late Jurassic The Late Jurassic is the third Epoch (geology), epoch of the Jurassic Period, and it spans the geologic time scale, geologic time from 161.5 ± 1.0 to 143.1 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic stratum, strata.Owen ...

was initially of subalkaline character (low

sodium Sodium is a chemical element; it has Symbol (chemistry), symbol Na (from Neo-Latin ) and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 element, group 1 of the peri ...

and

potassium Potassium is a chemical element; it has Symbol (chemistry), symbol K (from Neo-Latin ) and atomic number19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to ...

content), but turned increasingly alkaline in the Early Cretaceous.Marquillas et al., 2005 The rifts of Salta Basin developed in a time of generalized

along western South America.Ramos, 2009 It has been proposed that the

Salar de Atacama Salar de Atacama, located south of San Pedro de Atacama, is the largest Salt pan (geology), salt flat in Chile. It is surrounded by mountains and lacks drainage outlets. To the east, it is enclosed by the main chain of the Andes, while to the wes ...

depression in Chile was once a westward rift arm of the Salta Basin.Reutter et al., 2006

Stratigraphy

References

Bibliography

;General * * * * * * ;Guanaco Sonso Formation * ;Lumbrera Formation * * * ;Maíz Gordo Formation * ;Mealla Formation * ;Palo Pintado Formation * * * ;Piquete Formation * ;Quebrada de Los Colorados Formation * * * *

Description

Stratigraphy

References

Bibliography

Further reading