Landscape and relief evolution of the Central Mexican plateau in the final stage of Late Pleistocene and Holocene

Abstract

The paper describes the reconstructed history of landscapes and relief of the Central Mexican plateau in the final stage of Late Pleistocene and Holocene. The new stage of erosion has started in LGM with the formation of small lakes and further initiation of barrancos –gullies along the slopes of small and large volcanoes. This stage was not unidirectional, but had several alternating stages with the filling of depressions (small lakes, heads of barrancos, paleocuts) and their stabilization with the formation of heterochronous soils. The highest rates of gullies formation took place at the end of Pleistocene – beginning of Holocene, and at the present time when the badlands are forming. The stages of linear erosion (formation of barrancos) alternated with the increased sheet erosion (accumulation of colluviums in the depressions with further soil or tepetate formation). Soils were associated with the warm and wet enough climatic conditions about 13 350, 8 100, and 6 200 years ВР. Tepetates were formed under cool and wet environment. The role of small lakes was revealed. Small lakes at various levels being periodically broken through gave rise to the barrancos formation or dried out. The anthropogenic erosion had several stages: formation of the eroded sites (heads), barrancos formation inside the filled paleocuts, badlands formation. The “scalped” areas were formed in the sites of the contact of several exposed tepetates of various gullies. Such areas (badlands) may reach considerable size and are practically unsuitable for agricultural use.