The
Sunsás orogeny was an ancient orogeny active during the
Late Paleoproterozoic and
Mesoproterozoic and currently preserved as the
Sunsás orogen in the
Amazonian Craton in
South America. About 85% of the belt is covered by
Phanerozoic sediments. Among the remaining 15% of the orogen exposed at surface the best exposures lies around the Bolivia-Brazil border. It is thought that the original orogen once spanned an area from Venezuela to Argentina and Paraguay. The western and southeastern fringes of the Sunsás orogen have been incorporated into the
Andean orogeny and the
Brasiliano orogeny respectively. The Sunsás orogeny was active during four separate phases:
- Santa Helena orogeny 1465–1427 Ma
- Candeias orogeny 1371–1319 Ma
- San Andrés orogeny ca. 1275 Ma
- Nova Brasilândia orogeny 1180–1110 Ma