Geology

Chiapas [1] is Mexico’s eighth-largest state, covering 75,632 square kilometers (29,200 square miles), and certainly among the most geologically diverse. Geologists generally divide Chiapas into seven zones, five of which form a “stack” of long narrow bands of differing altitudes, all roughly parallel to the state’s Pacific coastline.

The Pacific coastal plain, aka the Soconusco or tierra caliente (hot lands), is the long hot plain running the length of the coast, averaging just 20–30 kilometers (12–18 miles) across. It was once covered in forest but is now one of the state’s most productive agricultural zones.

The imposing Sierra Madre de Chiapas mountain range juts up abruptly from the Pacific plain, with average altitudes of 1,500–3,000 meters (5,000–10,000 feet) plus the state’s highest peak, Volcán Tacaná, at nearly 4,100 meters (13,120 feet).

The northern slope of the Sierra Madre descends into Chiapas’s central depression, which has an altitude of 420–800 meters (1,400–2,650 feet) and a fairly hot dry climate. Tuxtla Gutiérrez [2] and Cañón del Sumidero [3] are located in this band.

Moving northward, the land leaps up again, this time forming the high cool central plateau, also referred to as Los Altos (the highlands), where San Cristóbal [4] is located. It boasts extensive, though fast diminishing, pine and oak forest and altitudes as high as 2,200 meters (7,250 feet).

To the northeast are the eastern highlands, sloping downward from the central plateau into the lush Lacandón jungle and Usumacinta river valley [5], along the Guatemalan border.

To the northwest are the northern highlands, which are higher and hillier than the eastern highlands and eventually give way to the Gulf coast plain, a hot lowland area in the state’s northernmost reaches, bordering the state of Tabasco [6].