Tinaja is a term originating in the American Southwest for surface pockets (depressions) formed in bedrock that occur below waterfalls, are carved out by spring flow or seepage, or are caused by sand and gravel scouring in intermittent streams (arroyos). Tinajas are an important source of surface water storage in arid environments.
These relatively rare landforms are important ecologically, because they support unique plant communities and provide important services to terrestrial wildlife.
- The Tinajas Altas ("high tinajas") in southern Arizona.
- Several in El Pinacate y Gran Desierto de Altar Biosphere Reserve, Sonora, Mexico.
- Osterkamp, W. R. 2008. Annotated Definitions of Selected Geomorphic Terms and Related Terms of Hydrology, Sedimentology, Soil Science and Ecology: Reston, Virginia, Open File Report 2008-1217, pp 49
- Fox, William (2005). Desert Water. Portland, Oregon: Graphic Arts Center Publishing Company. p. 12. ISBN 978-1-55868-858-2.
- Mabbutt, J. A. (1977). Desert Landforms. Canberra: Australian National University Press. p. 182. ISBN 978-0-7081-0437-8.
- Brown, T. B. and R. R. Johnson. 1983. The distribution of bedrock depressions (tinajas) as sources of surface water in Organ Pipe Cactus National Monument, Arizona. Journal of the Arizona-Nevada Academy of Science 18: 61-68.
- National Park Service (NPS). 2006. Organ Pipe Cactus National Monument Ecological Monitoring Report, 1997–2005, Chapter 14: Water Quality.http://www.nps.gov/orpi/naturescience/orpi-ecological-monitoring-report.htm