Changes in kerogen composition of the Vaca Muerta Fm., Argentina, across a thermal gradient affected by igneous intrusions

PINEDA JUAN; SPACAPAN JUAN; COMERIO M.; JAUSORO, I.; BRISSON IGNACIO

Brasil

Congreso; XVI Latin American Congress on Organic Geochemistry (ALAGO); 2023

The Vaca Muerta Formation (Late Jurassic–Early Cretaceous), considered a world-wide unconventional shale, constitutes the most prolific source rock of the Neuquén Basin, Argentina (Brisson et al., 2020). Recent studies have shown that organic matter has an impact on organic porosity development and thus exert a main control on oil and gas storage capacity. The evolution of organic porosity has been analyzed across the east–west regional maturation gradient of the basin (Spacapan et al., 2021). However, this evolution in local areas of the basin where igneous intrusions enhanced source rock maturation is not reported in the literature.Igneous intrusions can lead to an atypical maturation process on organic-rich shales, which can result in positive or negative effects on hydrocarbon generation and accumulation as was determined in Los Cavaos region (Mendoza, Argentina) of the Neuquén Basin (Spacapan et al., 2020). The objective of the present contribution is to reconstruct the changes on the kerogen composition across the thermal effects induced by horizontal intrusions (sills) and the development of organic pores in the Vaca Muerta Formation (VMF).