Rough and barren landscape of relict and largely uneroded lava fields
Malpaís, in the Southwestern United States, Spain, Mexico, and other Spanish-speaking regions, are rough and barren landscapes that consist of relict and largely uneroded lava fields exhibiting recognizable lava flows, volcanic cones, and other volcanic landforms. This type of volcanic landscape is extremely rough and difficult to traverse. It is characteristic of arid environments because in more humid climates, such rough terrains are smoothed by erosion and vegetation.
While the term describes many xeric places, it is strongly associated with Spanish-speaking countries and the Southwestern United States, where Spanish settlers named this landform.[1][2]
Badlands landform
The word 'malpaís' in Spanish translates to "badland," and this describes the area as being extremely rough and difficult to traverse and unusable for crops. Although a malpaís is often another word for the badlands that form by erosion of sedimentary rocks in the same environment, a malpaís is often associated with such types of lava plain terrain as found in a volcanic field. The geology of malpaís terrain is bare to thin layers of soil over lava with sparse vegetation. The lava fields usually consist of lava tube systems, sinkholes, pyroclastic deposits from cinder cone volcanoes, and ʻaʻā and pāhoehoe lava flows. The lava tubes can vary from intact caves to partial or completely collapsed passages. The collapsed tubes, sinkholes, and jagged ʻaʻā surfaces are what make malpaís terrain so difficult to navigate and cultivate, thereby earning their name.[3]
^Strahler, A. N., 1970, Introduction to Physical Geography, 2nd ed. John Wiley and Sopns. New York, New York. 486 pp. ISBN978-0471831686
^Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, eds. (2005) Glossary of Geology (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. ISBN0-922152-76-4