Salta Basin
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Salta Basin or Salta Rift Basin is a sedimentary basin located in the Argentine Northwest.[1][2] The basin started to accumulate sediments in the Early Cretaceous (Neocomian) and at present it has sedimentary deposits reaching thicknesses of 5,000 metres (16,000 ft). 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" and an "intra-continental rift". The basin developed under conditions of extensional tectonics and rift-associated volcanism.[1]
| Salta Basin | |
|---|---|
| Cuenca Salta | |
  Location of the basin in Argentina | |
| Coordinates | 23°40′S 66°07′W |
| Etymology | Salta Province |
| Region | Argentine Northwest |
| Country |  Argentina Bolivia Chile |
| State(s) | Salta, Jujuy, Tucumán Potosí Antofagasta |
| Cities | Salta |
| Characteristics | |
| On/Offshore | Onshore |
| Boundaries | Andes |
| Part of | Andean foreland basins |
| Geology | |
| Basin type | Foreland-on-rift basin or intracontinental rift basin |
| Plate | South American |
| Orogeny | Andean |
| Age | Neocomian-Neogene |
| Stratigraphy | Stratigraphy |
Description
The basin basement is composed of rocks belonging to the Puncoviscana Formation.[2] The volcanism that began in the Late Jurassic was initially of subalkaline character (low sodium and potassium content), but turned increasingly alkaline in the Early Cretaceous.[1]
The rifts of Salta Basin developed in a time of generalized extensional tectonics along western South America.[3] It has been proposed that the Salar de Atacama depression in Chile was once a westward rift arm of the Salta Basin.[4]
Stratigraphy
| Age | Group | Subgroup | Formation | Lithologies | Basin stage | Notes |
|---|---|---|---|---|---|---|
| Pliocene | Payogastilla | San Felipe | Conglomerates | Foreland | [5] | |
| Huayquerian | Jujuy | Piquete | [6][7] | |||
| Huayquerian | Guanaco Sonso | [8] | ||||
| Montehermosan | Palo Pintado | [9] | ||||
| Chasicoan | ||||||
| Laventan | Angastaco | [10][11] | ||||
| Friasian | ||||||
| Friasian | Metán | Jesús María | [11] | |||
| Friasian | Anta | [11] | ||||
| Early Miocene | Río Seco | [11] | ||||
| Priabonian | Los Colorados | [11] | ||||
| Casamayoran | Quebrada de los Colorados | [10] | ||||
| Salta | Santa Bárbara | Lumbrera | Late post-rift | [12][13] | ||
| Lutetian | ||||||
| Itaboraian | Maíz Gordo | [12][14] | ||||
| Thanetian | ||||||
| Peligran | Mealla | Sandstones, siltstones, conglomerates, paleosols | [12][15] | |||
| Selandian | Balbuena | Tunal | Early post-rift | [12] | ||
| Danian | Olmedo | [12] | ||||
| Yacoraite | Sandstones, limestones | [12] | ||||
| Maastrichtian | ||||||
| early Maastrichtian | Lecho | Sandstones | [12] | |||
| Campanian | Pirgua | Los Blanquitos | Sandstones | Late synrift | [12] | |
| Las Curtiembres | Early synrift | [12] | ||||
| Santonian | ||||||
| Coniacian | ||||||
| Turonian | ||||||
| Cenomanian | Isonza | Basalt | [12] | |||
| Albian | La Yesera | [12] | ||||
| Aptian | ||||||