# Altiplano
The Altiplano is a high, internally drained plateau in the Central Andes of South America, forming the northern part of the Altiplano-Puna plateau that stretches about 1,800 km along the crest of the Andes and reaches a width of 350–400 km.[1](https://www.annualreviews.org/content/journals/10.1146/annurev.earth.25.1.139) It is the second highest plateau on Earth, after Tibet, and it is unusual among large plateaus because it formed at a subduction zone plate margin rather than by continental collision.[2](https://academic.oup.com/gji/article/177/1/296/2078182) • [3](https://mapaspects.org/biblio/ref_7335/index.html) The plateau spans parts of Peru, Bolivia, Chile, and Argentina, bounded by the Western and Eastern Andean ranges.[4](https://www.sciencedirect.com/science/article/pii/S0895981122000165)
| Key fact | Detail |
|---|---|
| Extent | About 1,800 km long (north to south) and 350–400 km wide, across Peru, Bolivia, Chile, and Argentina[1](https://www.annualreviews.org/content/journals/10.1146/annurev.earth.25.1.139) • [4](https://www.sciencedirect.com/science/article/pii/S0895981122000165) |
| Elevation | The Altiplano averages about 3,800 m; the Puna to the south averages about 5,000 m[5](https://rocksandwater.net/pdfs/Sundell_et_al-2017-Tectonics_manuscript.pdf) • [6](https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2000JB000124) |
| Crustal thickness | Thickened to 60–80 km beneath the plateau[7](https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2003TC001519) |
| Start of uplift | Around 25 Ma in the Altiplano region; 5–10 million years later in the Puna[1](https://www.annualreviews.org/content/journals/10.1146/annurev.earth.25.1.139) |
| Magma body | The Altiplano-Puna Magma Body is the largest imaged magma reservoir on Earth[8](https://www.nature.com/articles/ncomms13185) |
| Climate | Arid to semi-arid; rainfall from 800–1,000 mm/yr near Lake Titicaca in the north to under 100 mm/yr near Salar de Uyuni in the south[9](https://www.cambridge.org/core/journals/quaternary-research/article/lakelevel-variability-in-salar-de-coipasa-bolivia-during-the-past-40000-yr/ACF88920D37FBDC1DBE9A64F134394A6) |
| Drainage | Low relief, high elevation, and generally internal drainage characterize the plateau[10](https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2008TC002341) |
## Geography and names
The plateau is known in southern Peru and western Bolivia as the Altiplano, a Spanish word meaning "high plain." It extends southward into Chile and Argentina, where it is called la Puna; the word puna also refers to mountain sickness.[11](https://pubs.usgs.gov/pp/p1386i/chile-arg/dry/) The Altiplano and Puna differ in structure but share low relief, high elevation, and internal drainage, which together make them a single physiographic region.[10](https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2008TC002341) As a sedimentary basin spanning several hundred kilometers, the Altiplano first took shape between the proto-Western [Cordillera](https://www.edgepedia.org/cordillera) and, to its east, a narrow band of uplifted ground that would develop into the Eastern Cordillera.[12](https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/97TC00495)
Notable features on the plateau include [Lake Titicaca](https://www.edgepedia.org/lake-titicaca), shared almost evenly by Peru and Bolivia, and the large salt flats of [Salar de Uyuni](https://www.edgepedia.org/salar-de-uyuni) and Salar de Coipasa in the drier south.[13](https://arxiv.org/abs/physics/0703182) • [14](https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2024-09/010091124.pdf) Aridity increases southward from the temperate shores of Lake Titicaca to the cold deserts around Salar de Uyuni.[14](https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2024-09/010091124.pdf)
## Tectonic origin and uplift
**Shortening and thickening.** The plateau formed where the oceanic Nazca plate subducts beneath the South American plate, producing extensive shortening and crustal thickening of the overriding plate.[10](https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2008TC002341) Uplift in the Altiplano region began around 25 million years ago, coincident with an increased convergence rate and an inferred shallowing of subduction; uplift in the Puna began 5–10 million years later.[1](https://www.annualreviews.org/content/journals/10.1146/annurev.earth.25.1.139) The plateau's rise is widely considered the isostatic (crust floating in equilibrium, rising as weight is removed) response to crustal shortening with thickening to as much as 60–80 km.[7](https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2003TC001519)
**The shortening budget.** Crustal thickening was produced primarily by horizontal shortening of a thermally softened lithosphere, but known shortening at the surface accounts for only 70–80% of the observed thickening. Magmatic addition and other processes, including lithospheric thinning, upper mantle hydration, and tectonic underplating, may therefore contribute significantly.[1](https://www.annualreviews.org/content/journals/10.1146/annurev.earth.25.1.139)
**Late Miocene rise.** Paleoelevation studies constrain rapid surface uplift, on the scale of kilometers, to have occurred between about 10 Ma and the present across the entire central Andean plateau.[15](https://www.sciencedirect.com/science/article/pii/S0012821X08002446) A synthesis of independent estimates places uplift since about 10 Ma at roughly 2,500 ± 1,000 m within the Altiplano, or as little as 1,100 ± 1,600 m in one reconstruction, alongside 1,200 ± 600 m on the Western Andean Slope and 1,700 ± 700 m in the Eastern Cordillera.[16](https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2010TC002661) Proposed mechanisms include crustal thickening and, in some models, isostatic rebound following removal of the lower lithosphere; in the northern Altiplano of southern Peru, convective removal of the lithosphere in a viscous drip has been invoked to explain rapid uplift and lower crustal flow.[17](https://doi.org/10.1002/2013TC003461) • [18](https://pmc.ncbi.nlm.nih.gov/articles/PMC8975996/)
## The Altiplano-Puna Magma Body
Beneath the Altiplano and northern Puna, a zone of partial melting at mid-crustal depth has been established by independent geophysical observations, including zones of extremely high electrical conductivity and broad low seismic velocity.[19](https://www.sciencedirect.com/science/article/pii/S0031920114002131) This Altiplano-Puna Magma Body (APMB) is the largest imaged magma reservoir on Earth. A long-wavelength topographic dome overlies its seismically measured extent, and gravity data suggest the uplift is isostatically compensated; modeling indicates that magmatic addition may contribute to surface uplift on a scale comparable to lithospheric removal.[8](https://www.nature.com/articles/ncomms13185)
## Climate and water
Modern climate on the Altiplano is arid to semi-arid. Rainfall ranges from 800 to 1,000 mm per year in the north near Lake Titicaca to under 100 mm per year in the south near Salar de Uyuni.[9](https://www.cambridge.org/core/journals/quaternary-research/article/lakelevel-variability-in-salar-de-coipasa-bolivia-during-the-past-40000-yr/ACF88920D37FBDC1DBE9A64F134394A6) Elevated shoreline deposits, including carbonate benches above Salar de Uyuni, Salar de Coipasa, Lago Poopó, and Lake Titicaca, record past lake-level variability over the past roughly 40,000 years.[9](https://www.cambridge.org/core/journals/quaternary-research/article/lakelevel-variability-in-salar-de-coipasa-bolivia-during-the-past-40000-yr/ACF88920D37FBDC1DBE9A64F134394A6)
## Human use
The plateau has supported agriculture and metallurgy for centuries. In the Intersalar region of southern Bolivia, between the two large salt flats, pre-Hispanic communities practiced wetland irrigation and metallurgy in the 14th and 15th centuries CE.[14](https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2024-09/010091124.pdf) In modern Bolivia, the small size of land holdings is a serious constraint on Altiplano agriculture, where the policy problem is how to intensify production and raise productivity at the margin.[20](https://documents1.worldbank.org/curated/en/297301468914752992/pdf/Natural-resource-management-in-Bolivia-30-years-of-experience.pdf)
## References
1. [Allmendinger, R. W., Jordan, T. E., Kay, S. M., & Isacks, B. L. (1997). The Evolution of the Altiplano-Puna Plateau of the Central Andes. Annual Review of Earth and Planetary Sciences 25:139–174.](https://www.annualreviews.org/content/journals/10.1146/annurev.earth.25.1.139)
2. [Receiver function images from the Moho and the slab beneath the Altiplano and Puna plateaus in the Central Andes, Geophysical Journal International](https://academic.oup.com/gji/article/177/1/296/2078182)
3. [Uplift history of the Central and Northern Andes: A review, Geological Society of America Bulletin](https://mapaspects.org/biblio/ref_7335/index.html)
4. [The Unique Altiplano-Puna Plateau: Environmental Perspectives, ScienceDirect](https://www.sciencedirect.com/science/article/pii/S0895981122000165)
5. [Sundell et al. (2017). Peruvian Altiplano stratigraphy highlights along-strike variability in foreland basin](https://rocksandwater.net/pdfs/Sundell_et_al-2017-Tectonics_manuscript.pdf)
6. [Beck (2002). The nature of orogenic crust in the central Andes, Journal of Geophysical Research](https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2000JB000124)
7. [Victor (2004). Uplift of the western Altiplano plateau: Evidence from the Precordillera between 20° and 21°S, Tectonics](https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2003TC001519)
8. [Surface uplift in the Central Andes driven by growth of the Altiplano Puna Magma Body, Nature Communications](https://www.nature.com/articles/ncomms13185)
9. [Lake-level variability in Salar de Coipasa, Bolivia during the past ∼40,000 yr, Quaternary Research](https://www.cambridge.org/core/journals/quaternary-research/article/lakelevel-variability-in-salar-de-coipasa-bolivia-during-the-past-40000-yr/ACF88920D37FBDC1DBE9A64F134394A6)
10. [Schoenbohm (2009). Normal faulting along the southern margin of the Puna Plateau, Tectonics](https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2008TC002341)
11. [USGS Professional Paper 1386-I: Chile and Argentina – Dry Andes](https://pubs.usgs.gov/pp/p1386i/chile-arg/dry/)
12. [Lamb (1997). Origin of the high plateau in the central Andes, Bolivia, South America, Tectonics](https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/97TC00495)
13. [Lake Titicaca – Physics of an Inherited Hydropower Macroproject Proposal, arXiv](https://arxiv.org/abs/physics/0703182)
14. [Pre-hispanic wetland irrigation and metallurgy in the South Andean Altiplano (Intersalar Region, Bolivia, XIVth and XVth century CE)](https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2024-09/010091124.pdf)
15. [Paleosurfaces, paleoelevation, and the mechanisms for the late Miocene topographic development of the Altiplano plateau, Earth and Planetary Science Letters](https://www.sciencedirect.com/science/article/pii/S0012821X08002446)
16. [Jordan (2010). Uplift of the Altiplano-Puna plateau: A view from the west, Tectonics](https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2010TC002661)
17. [Carrapa (2014). Uplift of the Central Andes of NW Argentina associated with upper crustal shortening, Tectonics](https://doi.org/10.1002/2013TC003461)
18. [Rapid surface uplift and crustal flow in the Central Andes (southern Peru) controlled by lithospheric drip dynamics, PMC](https://pmc.ncbi.nlm.nih.gov/articles/PMC8975996/)
19. [Thermal and geodynamic contributions to the elevation of the Altiplano–Puna plateau, ScienceDirect](https://www.sciencedirect.com/science/article/pii/S0031920114002131)
20. [Natural resource management in Bolivia: 30 years of experience, World Bank](https://documents1.worldbank.org/curated/en/297301468914752992/pdf/Natural-resource-management-in-Bolivia-30-years-of-experience.pdf)
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*Topic: Encyclopedia › Places and geography › Landforms and terrestrial features › Mountains, plains, and other land terrain › Plateaus, mesas, and buttes*
*Initially written Sep 17, 2026 · Reviewed: Oct 21, 2026 · Edited: Oct 15, 2026; Oct 21, 2026 · Last review: Oct 21, 2026*
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