Coupled Microbiological–Isotopic Approach for Studying Hydrodynamics in Deep Reservoirs: The Case of the Val d’Agri Oilfield (Southern Italy)

Abstract

The studies upstream of the petroleum industry include oil and gas geological exploration and are usually focused on geological, structural, geophysical, and modeling techniques. In this research, the application of a coupled microbiological–isotopic approach was explored to assess its potential as an adequate characterization and monitoring tool of geofluids in oilfield areas, in order to expand and refine the information acquired through more consolidated practices. The test site was selected within the Val d’Agri oilfield, where some natural hydrocarbon springs have been documented since the 19th century in the Tramutola area. Close to these springs, several tens of exploration and production wells were drilled in the first half of the 20th century. The results demonstrated the effectiveness of the proposed approach for the analysis of fluid dynamics in complex systems, such as oilfield areas, and highlighted the capacity of microbial communities to “behave” as “bio-thermometers”, that is, as indicators of the different temperatures in various subsurface compartments.

Hydrogeological Behaviour and Geochemical Features of Waters in Evaporite-Bearing Low-Permeability Successions: A Case Study in Southern Sicily, Italy

“…Regarding the affinity of the sampled groundwaters, all groups plotted along the local meteoric water lines available in the scientific literature [55][56][57][58][59][60][61][62], being consistent with those of rainwater collected in the study area during the observation period; this finding suggests a meteoric origin for the analysed waters (Figure 9), with no influence of ascending fluids coming from deep reservoirs, the isotopic signature of which are notably different from those of actual precipitations [35]. Regarding tritium, the rainwater samples had high 3 H contents (6.2 to 10.8 T.U.…”

“…The usefulness and the efficacy of a coupled isotopic-microbiological approach has been verified in other complex hydrogeological settings (e.g., [35]), taking into consideration how microorganisms migrate in the subsurface (e.g., [36]).…”

Potential Enhancement of the In-Situ Bioremediation of Contaminated Sites through the Isolation and Screening of Bacterial Strains in Natural Hydrocarbon Springs

“…The Rio Cavolo Unit is made up of clays, micaceous limestone and rare marly layers. The P art well (404 m deep) intercepted oil and gas at different depths [18,19].…”

“…The hydrocarbon springs S1 and S2 flow out along a fault zone which enhances fluid upflow and allows the mixing of hydrocarbons and gas (mainly CH 4 and H 2 S) [22] with the local groundwater, which is primarily fed by the nearby carbonate aquifer (Figure 2) [19]. The groundwater intercepted by the P art well is fed by a more prolonged pathway in a relatively deep aquifer made of Scisti Silicei (Figure 3) [19]. This deep groundwater naturally flows eastwards, towards the alluvial aquifer of the Agri Valley.…”

“…Water 2020, 12, x FOR PEER REVIEW 3 of 19 of clays, micaceous limestone and rare marly layers. The Part well (404 m deep) intercepted oil and gas at different depths [18,19]. Different hydrogeological series complexes crop out at the study site [20]: (i) carbonate rocks belonging to the Mesozoic carbonate platform series complexes, characterized by very high permeability due to a well-developed fracture network and karst conduits; (ii) sedimentary rocks belonging to the syn-orogenic turbidite series complexes and the outer and the inner basins' series complexes, characterized by a permeability ranging from very low to low due to a mixed porefracture network.…”