The Sierra Chichinautzin volcanic field is located in the Trans-Mexican Volcanic Belt, approximately 350 km from where the Cocos plate subducts beneath the North American plate. According to The Smithsonian Institution's Global Volcanism Program, "The massive Chichinautzin volcanic field covers a 90-km-long, E-W-trending area immediately south of Mexico City. The Sierra Chichinautzin, formed primarily of overlapping small cinder cones and shield volcanoes, creates a broad topographic barrier at the southern end of the Basin of Mexico that extends from the eastern flank of Nevado de Toluca to the western flank of Iztaccíhuatl volcano. The volcanic field contains more than 220 Pleistocene-to-Holocene monogenetic vents. The best-known eruption occurred about 1670 radiocarbon years ago from the Xitle scoria cone, NE of the Volcán Ajusco lava-dome complex, which at 3930 m forms the highest peak of the Sierra Chichinautzin. The Xitle eruption produced a massive basaltic tube-fed lava flow that covered agricultural lands as well as pyramids and other structures of Cuicuilco and adjacent prehispanic urban centers. The southern part of Mexico City and the National University of Mexico lie atop the distal end of the 13-km-long lava flow."

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