Estratigrafia fÃsica e deformaÃÃo do sistema lacustre carbonÃtico (aptiano-albiano) da bacia do Araripe em afloramentos selecionados / Physical Estratigrafia and deformation of the carbonÃtico lacustrine system (aptiano-albiano) of the basin of the Araripe in selected outcrops

AUTOR(ES)
DATA DE PUBLICAÇÃO

2003

RESUMO

The purpose of this thesis was to study the physical stratigraphy of the carbonate deposits exposed in the Araripe Basin, in order to help in the quality prediction of the subsurface analogous reservoirs. The following methods were applied: field work for the selection of outcrops, and consecutive stratigraphical and sedimentological descriptions, sample collection, identification and measurement of deformationals structures (faults and fractures), GPR data and photography acquisition. Laboratory work for stratigraphical correlation, petrography analysis and data processing were realized. The Crato Formation presents typical facies of low-energy ramp-type lake margins, formed in a lacustrine transgressive systems tract. The carbonate units represent smaller time order cycles. Three deformationals events affected the Crato Formation. The first event (D1) was distensive. Normal microfaults (ENE and NW), loop beddings and slumps, a result of small seismic pulses were formed. These microstructures are observed in some layers of the carbonate units. The second event (D2) was compressive and reverse fauts, diping to SW and NE, were generated. These faults cut all C6 carbonate unit and it represents a tectonic inversion in the basin. That probably resulted in a extreme low lake level, possibiliting the after deposition of Ipubi Formation evaporites. The last event (D3) was distensive and was responsible for the reactivation of the fauts generated in D2, now as normal fauts. It is also observed fractures, closed or opened, some of them filled out by calcite. The GPR data obtained a very good quality. The lack of brittle structures didnÂt allow your recognition in the line acquired . It is believed that the brittle structures can be recognized with easiness in outcrops where are recognized with more frequency

ASSUNTO(S)

gpr crato formation anÃlogo de reservatÃrio geociencias bacia do araripe physical estratigrafia deformation carbonatos deformaÃÃo estratigrafia fÃsica formaÃÃo crato gpr basin of the araripe carbonates analogous of reservoir

ACESSO AO ARTIGO

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