Oaxaca - Geography

Geography

The state is located in the south of Mexico, bordered by the states of Puebla, Veracruz, Chiapas and Guerrero with the Pacific Ocean to the south. It has a territory of 93,967 km2 (36,281 sq mi), accounting for less than 5% of Mexico’s territory. Here several mountain chains come together, with the elevation varying from sea level to 3,759 m (12,333 ft) asl, averaging at 1,500 m (4,921 ft) asl. Oaxaca has one of the most rugged terrains in Mexico, with mountain ranges that abruptly fall into the sea. Between these mountains are mostly narrow valleys, canyons and ravines. Major elevations in the state include Cempoaltepetl (3,396 m/11,142 ft asl), El Espinazo del Diablo, Nindú Naxinda Yucunino and Cerro Encantado. Oaxaca’s has 533 km (331 mi) of coastline with nine major bays.

The mountains are mostly formed by the convergence of the Sierra Madre del Sur, the Sierra Madre de Oaxaca and the Sierra Atravesada into what is called the Oaxaca Complex (Complejo Oaxaqueño). The Sierra Madre del Sur runs along the coast with an average width of 150 km (93 mi) and a minimum height of 2,000 meters (6,562 ft) asl with peaks over 2,500 m (8,202 ft) asl. In various regions the chain is locally known by other names, such as the Sierra de Miahuatlán and the Sierra de la Garza. The Sierra Madre de Oaxaca enters the state from the Puebla and Veracruz borders in the Tuxtepec region, running northwest to southeast towards the Central Valleys region, then onto the Tehuantepec area. Local names for parts of this range include Sierra de Tamazulapan, Sierra de Nochixtlan, Sierra de Huautla, Sierra de Juárez, Sierra de Ixtlan and others. Average altitude is 2,500 m (8,202 ft) asl with peaks over 3,000 m (9,843 ft) asl and width averages at about 75 km (47 mi). The Sierra Atravesada is a prolongation of the Sierra Madre de Chiapas. This range is not as high as the other two with an average elevation of just over 600 meters (1,969 ft). Most of it is located in the Juchitán district running east-west.

The only valleys of any real size are the Central Valleys between Etla and Miahuatlan, which contains the city of Oaxaca. Smaller populated valleys include Nochixtlan, Nejapa, Cuicatlan and Tuxtepec. Small mesas contain population centers such as Putla, Juxtlahuaca, Tamazulapan, Zacatepec, Tlaxiaco and Huajuapan. The largest canyons in the state are those in the Cuicatlan area and include the Cortés, Galicia and María in the municipality of Tlaxiaco. There are a very large number of small canyons as well as ravines and arroyos of all sizes.

The mountainous terrain allows for no navigable rivers; instead, there are a large number of smaller ones, which often change name from area to area. The continental divide passes through the state, meaning that there is drainage towards both the Gulf of Mexico and the Pacific Ocean. Most of the drainage towards the Gulf is represented by the Papaloapan and Coatzacoalcos Rivers and their tributaries such as the Grande and Salado Rivers. Three rivers account for most of the water headed for the Pacific: the Mixteco, Atoyac and Tehuantepec Rivers with their tributaries. Other important rivers and streams include the Tequisistlán, Santo Domingo, Putla, Minas, Puxmetacán-Trinidad, La Arena, Cajonos, Tenango, Tonto, Huamelula, San Antonio, Ayutla, Joquila, Copalita, Calapa, Colotepec, Aguacatenango-Jaltepec, Los Perros, El Corte, Espíritu Santo, Sarabia, Ostuta, Petapa and Petlapa.