Viagem realizada em Sete Cidades - PI e Ubajara - CE.

Abstract

Report of field studies carried out on January 6 and 7, 1995, in the national parks of Sete Cidades and Ubajara, an in-depth study of its rock formations, its origin in tectonic history, rainfall - differential erosion, the place is settled in the middle of the basin of the Parnaíba River, with an extension of 600,000 km. In its extension it covers almost all Maranhão.