Evolución geológica y geomorfología del complejo dómico Los Pitos, norte de la Cuenca de México

Abstract

The Basin of Mexico consists of a high plateau (2,240 m) surrounded by volcanic mountains, which are principally Pliocene to Quaternary in age. Other volcanic complexes of varying sizes are found along its vast plateau. One of these, the volcanic dome complex Los Pitos, is approximately ten kilometers in diameter and 2,950 meters high. Below the 2,600 meter level, there is a piedmont consisting of Upper Pliocene rhyolitic pyroclastic flows with a radius of 4-5 kilometer. The upper level of the sierra is comprised of small volcanic domes. Other smaller volcanoes developed in the Quaternary. Some of these are composed of dacite on the outer fringes, while others to the south , made up of andesite to basalt, represent more recent volcanic activity. The overlapping of landforms of contrasting lithology (rhyolite to basalt) and age make this Sierra a unique structure in the Basin of Mexico, where andesites and dacites predominate. This geomorphologic study includes a map that analyzes the relief in 23 units. Present human activities such as deforestation and mining have a strong influence on landforms and geomorphic processes.