Stratigraphic Relations of the Ipubi Formation: Siliciclastic-Evaporitic Succession of the Araripe Basin
AUTOR(ES)
FABIN, CARLOS E., CORREIA FILHO, OSVALDO J., ALENCAR, MÁRCIO L., BARBOSA, JOSÉ A., MIRANDA, TIAGO S. DE, NEUMANN, VIRGÍNIO H., GOMES, IGOR F., SANTANA, FELIPE R. DE
FONTE
An. Acad. Bras. Ciênc.
DATA DE PUBLICAÇÃO
25/06/2018
RESUMO
ABSTRACT The Ipubi Formation represents the Aptian-Albian siliciclastic-evaporitic succession of Araripe Basin, NE Brazil. This succession comprises siliciclastic rocks (bituminous shales and claystones) and evaporites (gypsum and secondary anhydrite) and represents part of the lacustrine-shallow marine post-rift phase I. This study used sequence stratigraphy concepts to define the relations between changes in the relative lake level and the formation of Ipubi deposits. Results show that the organic-rich shales of the Ipubi Formation formed during a transgressive pulse that covered large areas of the proximal domains. These deposits overlie a regional unconformity that marks the end of the deposition of the underlying Crato Formation. A High Stand stage that followed the transgression influenced the formation of evaporitic deposits. Climate conditions played a major role in influencing the triggering and stopping of evaporite deposition. Thus, a new relative lake level fall event caused the exposure of the Ipubi Formation deposits, and created another regional subaerial unconformity accompanied by widespread karstification of evaporite beds. A posterior transgression caused the deposition of siliciclastic rocks of the Romualdo Formation over the Ipubi Formation strata, and also promoted a new event of karstification of the Ipubi upper evaporite beds.
Documentos Relacionados
- The Paripueira evaporitic interval of Maceio Sub-Basin - Sergipe/Alagoas basin
- Araçatuba Formation: palustrine deposits from the initial sedimentation phase of the Bauru Basin
- The ANUROFAUNA Of FORMATION CRATO, EOCRETÃCEO Of the BASIN Of the ARARIPE
- Microfacies and diagenetic evolution of the limestones of the upper part of the Crato Formation, Araripe Basin, northeastern Brazil
- Early Creatceous gymnosperms from the Crato Formation, Araripe Basin, Northeast Brazil