Produção Nacional
Chapada Diamantina: A Remarkable Landscape Dominated by Mountains and Plateaus
2015; Springer Nature (Netherlands); Linguagem: Inglês
10.1007/978-94-017-8023-0_19
ISSN2213-2104
AutoresCarlos César Uchôa de Lima, Marjorie Csekö Nolasco,
Tópico(s)Karst Systems and Hydrogeology
ResumoChapada Diamantina is located in the central portion of Bahia state in northeastern Brazil and is marked by mountainous relief with pronounced scarps, deep valleys, and high plateaus. Lithologically, this region is dominated by metasedimentary rocks formed over a period of 900 million years during the Proterozoic. Between 500 and 600 million years ago, the last major tectonic event raised the sedimentary package in a sequence of alternating synclinal and anticlinal folds that are cut by faults in several directions. This arrangement, combined with the current fluvial system, has resulted in a relief marked by flattop elevations that reach over 1,800 m in altitude. Two major geomorphological domains are observed at Chapada Diamantina. The karstic domain is dominated by flat relief and slightly undulating terrain. The main features include collapse sinkholes and caves that extend into galleries for up to tens of kilometers. The lithostructural domain consists mainly of quartzite rocks and is divided into three subdomains: (1) Rio de Contas in the western portion, with a very irregular relief and marked by lowered anticlines and hanging synclines with centers emptied by differential erosion, which exposes its flanks in hogbacks; (2) Paraguaçu in the eastern portion, where the flank of a large anticline that is raised and slightly inclined toward the east predominates, and (3) Central Pediplain in the central-southern portion (marked by flat to hilly terrain with some residual elevations). In addition to fluvial morphodynamics, several anthropogenic features have developed over the past 200 years from mining activity.
Referência(s)