Petrographic, mineralogical and geochemical characterization of organic-rich, fine-grained deposits in the Pilmatué Member of the Neuquén Basin: implications for the explorations and development of unconventional reservoirs.

REMÍREZ, M.; SPALLETTI, L. E ISLA, M.

Buenos Aires

Congreso; AAPG International Conference and Exhibition; 2020

American Association of Petroleum Geologists

Sedimentological attributes of mudstoneshave important implications in unconventional reservoirs. Understandingthe variations of the fine-grained deposits in a depositional system constitute a key point for the exploration and development of such reservoirs. The aim of this contribution isto evaluate the influence of terrigenous input, carbonate productivity and redox conditions of a mixed (clastic-carbonate) marine ramp, through high-resolution sedimentology and inorganic geochemistryinthe offshore deposits of the Pilmatué Member, Agrio Formation (Late Valanginian ? Early Hauterivian, Neuquén Basin, Argentina).Six stratigraphic sections (350-650 m thick) were logged in a north-south transect of 50 km in the northernNeuquén province. A total of 400 samples were processed using handheld X-ray fluorescence equipment. The elements used for this characterization were: SiO2, K2O, TiO2, Al2O3, Th and Zr, as detrital supply proxies; CaO and Sr as proxies of carbonate productivity; and V, Co, Cu, Mo, S and Ni as redox proxies. Additionally, textural and mineralogical features were defined through X-ray diffraction for mineralogical studies and thin sections for textural definition.