Tectonic cycles and sedimentary sequences in the Brazilian intracratonic basins

Research Article| February 01, 1978 Tectonic cycles and sedimentary sequences in the Brazilian intracratonic basins PAULO CESAR SOARES; PAULO CESAR SOARES 1Departamento de Geociências, Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil Search for other works by this author on: GSW Google Scholar PAULO MILTON BARBOSA LANDIM; PAULO MILTON BARBOSA LANDIM 1Departamento de Geociências, Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil Search for other works by this author on: GSW Google Scholar VICENTE JOSE FULFARO VICENTE JOSE FULFARO 2Instituto de Geociências, Universidade de São Paulo, São Paulo, Brazil Search for other works by this author on: GSW Google Scholar Author and Article Information PAULO CESAR SOARES 1Departamento de Geociências, Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil PAULO MILTON BARBOSA LANDIM 1Departamento de Geociências, Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil VICENTE JOSE FULFARO 2Instituto de Geociências, Universidade de São Paulo, São Paulo, Brazil Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1978) 89 (2): 181–191. https://doi.org/10.1130/0016-7606(1978)892.0.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation PAULO CESAR SOARES, PAULO MILTON BARBOSA LANDIM, VICENTE JOSE FULFARO; Tectonic cycles and sedimentary sequences in the Brazilian intracratonic basins. GSA Bulletin 1978;; 89 (2): 181–191. doi: https://doi.org/10.1130/0016-7606(1978)892.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The geometry and petrology of sedimentary rocks preserved in the three intracratonic basins of the Brazilian craton (Paraná, Parnaiba, and Amazon) indicate the history and character of vertical movements of the cratonic area. Cyclic successions of erosional and depositional events are synchronous on the Brazilian craton and are correlated with cratons of other continents. The principal evolutionary stages of the Brazilian craton are interpreted as tectonic-sedimentary cycles, each represented by a stratigraphic record identified as a sequence, and each distinguished by its own special characteristics.Cambrian-Ordovician sedimentary rocks, representing deposition in paraplatform basins during a transitional stage at the close of the Brazilian orogenic cycle, are assigned to the Alpha sequence. The Beta (Ordovician and Silurian), Gamma (Devonian–early Carboniferous), and Delta (late Carboniferous–Late Permian sequences) and the Delta-A subsequence (Middle Triassic–Jurassic), corresponding to geotectonic cycles of the cratonic stabilization stage, indicate accumulation in large subsiding basins. The succession of facies in each of these sequences documents cyclical changes in the ratio of sediment supply to subsidence. Marine transgression and basin subsidence increased progressively through the Devonian phase of the Gamma sequence and declined thereafter, in a pattern similar to that of the North American craton and the Russian platform. The frequency of stratigraphic discordances in the three lower sequences suggests a higher degree of cratonic upwarping, progressively diminishing to a stage of maximum stabilization during Delta-A deposition, perhaps related to conditions immediately prior to rupture of the Gondwana plate.Breakup of the Gondwana plate, accompanied by volcanism and remobilization of cratonic areas, initiated the reactivation stage during which two geotectonic cycles are recognized. The first, represented by the Epsilon sequence (Cretaceous), began with local subsidence in isolated basins, followed by widespread continental sedimentation under platform conditions. The second reactivation cycle was responsible for accumulation of the Zeta sequence (Cenozoic), which was characterized by thin residual deposits on an extensive Tertiary peneplain and by accumulations in Quaternary basins, the latter of minor importance except where adjacent to the uplifted eastern continental margin. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.