Estudo geoquímico da Formação Ponta Grossa visando à prospecção de gás natural não convencional no Paraná e norte de Santa Catarina

Abstract

In order to identify possible unconventional natural gas reservoirs in the Ponta Grossa Formation and to assess, probabilistically, undiscovered recoverable resources, stratigraphic and geochemical analyzes were performed using twelve exploratory wells located in the south-central portion of the Paraná Basin, which has a privileged location between the brazilian southeast and south regions, where the largest gas and electricity consuming centers are located. The simulation conditions were based on exploratory data from existing wells and unpublished results of Organic Geochemistry and x-Ray Diffraction from the 1-COST-1P-PR well, near Barra Bonita gas field. The best estimate (P50) is 2,9 billion cubic meters standard. If five existing wells are deepened at least to the top of Furnas Formation, the additional unconventional resource (P50) is 1,9 billion cubic meters. It is not recommended to extrapolate the volumes calculated for other basin’s areas without knowing the new data and without making the respective adjustments. The statements and conclusions are subject to an expressive set of risks, uncertainties and assumptions and, therefore, do not reflect the totality of the circumstances and the scenarios that may affect the investment decisions and their results. The Devonian source rocks’ geochemical features were compared between zones with distinct thermal maturities. Although the Frasnian source rock has TOC up to 4% in the immature zone, twice the TOC of the Emsian source rock, its depositional conditions were more oxidizing, therefore, less suitable to organic matter preservation. Furthermore, the occurrence area of Frasnian source rock is smaller, limited to southern Mato Grosso, where it is immature, and to northern/northwestern Paraná, where it is severely affected by igneous’ heat. In case the geological, technological, economic, environmental and legal factors are favorable to the resumption of exploratory activities, the results may contribute to the planning of future research on unconventional natural gas reservoirs