Caracterização geoquímica e efeito térmico de intrusão de diabásio na matéria orgânica da Formação Irati, poço FP-12-SP, bacia do Paraná

• Autor(a) principal: Seifert, Ingrid Alves
• Data de Publicação: 2013
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/7093
• topic: Irati Formation; Oleaginous shale; Organic geochemistry; Geochemical stratigraphy; Biomarkers; Formação Irati; Folhelho oleígeno; Geoquímica orgânica; Estratigrafia química; Biomarcadores; CNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOLOGIA::ESTRATIGRAFIA

The study aimed to detailed organic geochemistry characterization (total organic carbon, insoluble residue, sulfur , Rock-Eval pyrolysis and biomarkers) of the Irati Formation through pioneering well FP-12-SP located near the region of Anhembi (SP), and to analysis of changes in these parameters due to the thermal effect of diabase intrusions. From these data it was defined eight (8) chemostratigraphic units, as well as the potential generator of each unit, the type of kerogen and geochemical parameters through the saturated biomarkers, and, finally, it was indicated the changes caused by thermal effect of intrusives on sediments. The Taquaral Member has low content of total organic carbon, kerogen type III/IV, with a high proportion of linear alkanes and cycloalkanes, predominance of C27 steranes compared to C29, with indications of marine environment with normal salinity. The Member Assistência is characterized by relatively high levels of total organic carbon increasing to the top, interleaving siliciclastic levels with carbonate, generation potential reaching excellent and hydrogen index predominant to oil and condensate, low proportion of n-alkanes relative to cycloalkanes and branched alkanes and gammacerane indicating hypersaline marine environment with drowning to the top. The thermal effect is seen from 3 meters below and 10 meters above the sill with maturation of the organic matter at 9.5 m from the nearest sill. The propagation of heat above the threshold was higher than below due to difference in thermal conductivity between the shale and carbonate, where the maximum constraint with increasing salinity in Chemostratigraphic Unit E, indicated by the presence of gammacerane, may have amplified the passage of heat to the top.