This paper presents a numerical simulation study evaluating carbon dioxide capture and storage (CCS) feasibility for the Turceni Power Plant in Oltenia, Romania, using the nearby depleted Bibești-Bulbuceni gas reservoir. A comprehensive reservoir model was developed using Petrel software, integrating geological and reservoir engineering data for the formations of the Bibești-Bulbuceni structure, which is part of the western Moesian Platform. The static model incorporated realistic petrophysical inputs for the Meotian reservoirs. Dynamic simulations were performed using Eclipse compositional simulator with Peng–Robinson equation of state for a CH4-CO₂ system. The model was initialized with natural gas initially in place at 149 bar reservoir pressure, then produced through depletion to 20.85 bar final pressure, achieving 80% recovery factor. CO₂ injection simulations modeled a phased 19-well injection program over 25 years, with individual well constraints of 100 bar bottom-hole pressure and 200,000 Sm³/day injection rates. Results demonstrate successful injection of a 60 Mt CO₂, with final reservoir pressure reaching 101 bar. The modeling framework validates the technical feasibility of transforming Turceni’s power generation into a net-zero process through CCS implementation. Key limitations include simplified geochemical interactions and relying on historical data with associated uncertainties. This study provides quantitative evidence for CCS viability in depleted hydrocarbon reservoirs, supporting industrial decarbonization strategies. The strategy not only aligns with the EU’s climate-neutral policy but also enhances local energy security by repurposing existing geological resources. The findings highlight the potential of CCS to bridge the gap between current energy systems and a sustainable, climate-neutral future.

Carbon capture and storage (CCS) represents a critical technology for achieving climate neutrality targets, particularly for regions with significant industrial CO₂ emissions. This study presents a comprehensive numerical simulation assessment of CO₂ geological storage potential in the Sarmatian formations of the Getic Platform, Romania, located near the Turceni power plant—one of Europe’s largest thermal power facilities. Using ECLIPSE 300 compositional simulator with the CO2STORE option, we developed reservoir dynamic models incorporating geological properties, fluid characteristics, and pressure–volume–temperature (PVT) data specific to the Sarmatian aquifer system. Multiple injection scenarios were evaluated, including configurations with 3, 4, and 5 injection wells at varying inter-well distances (2000–10,000 m). The simulations covered a 20-year injection period followed by 300 years of monitoring. While previous assessments have provided static capacity estimates for Sarmatian formations, this study presents the first dynamic simulation-based evaluation of multi-well injection scenarios and long-term CO₂ trapping behavior in this geological setting, directly linked to the Turceni Power Plant emissions profile. Results demonstrate that the study area (Zone V) can accommodate the target CO₂ injection rate of 2.07 × 10⁶ Sm³/day using five injection wells, with final reservoir pressure increasing only 7–9 bar above initial conditions, well below fracture pressure thresholds (~280 bar). Long-term simulations reveal favorable CO₂ trapping behavior, with significant portions immobilized through residual and dissolution trapping mechanisms. The static storage capacity was estimated at 2.44 × 10¹⁴ kg CO₂. These findings support the technical feasibility of large-scale CO₂ storage in Romanian Sarmatian formations, providing quantitative evidence for CCS implementation strategies in the region.

Open Access Published: 02 December 2016 New Relations of Water Saturation’s Calculus from Well Logs Ion Malureanu¹, Tudor Boaca² & Daniela-Doina Neagu¹ Acta Geophysica volume 64, pages 1542–1562 (2016)Cite this article 682 Accesses 2 Citations Metrics details Abstract The saturation in water or hydrocarbon is an important petrophysical parameter used for the evaluation of oil and gas reservoirs. It represents the amount of hydrocarbons in a reservoir. There are many relations to determine the water saturation from well logs by using the physical properties of rocks. The accurate determination of the hydrocarbon formation or the water saturation is given by the accuracy of the parameters used for calculating and by the relations used. Download to read the full article text References Alger, R.P. (1966), Interpretation of electric logs in fresh water wells in unconsolidated formations. In: SPWLA 7th Annual Logging Symposium, 9-11 May 1966, Tulsa, Oklahoma, SPWLA-1966-CC. 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Article Google Scholar Download references Author information Affiliations Faculty of Petroleum and Gas Engineering, Department of Petroleum Geology and Reservoir Engineering, Petroleum-Gas University of Ploiesti, Ploiesti, Romania Ion Malureanu & Daniela-Doina Neagu Faculty of Letters and Science, Department of Information Technology, Mathematics and Physics, Petroleum-Gas University of Ploiesti, Ploiesti, Romania Tudor Boaca Authors Ion Malureanu View author publications You can also search for this author in PubMed Google Scholar Tudor Boaca View author publications You can also search for this author in PubMed Google Scholar Daniela-Doina Neagu View author publications You can also search for this author in PubMed Google Scholar Corresponding author Correspondence to Ion Malureanu. 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Acta Geophys. 64, 1542–1562 (2016). https://doi.org/10.1515/acgeo-2016-0063 Download citation Received: 29 April 2015 Revised: 24 November 2015 Accepted: 07 January 2016 Published: 02 December 2016 Issue Date: October 2016 DOI : https://doi.org/10.1515/acgeo-2016-0063 Share this article Anyone you share the following link with will be able to read this content: Get shareable link Sorry, a shareable link is not currently available for this article. Copy to clipboard Provided by the Springer Nature SharedIt content-sharing initiative Key words water saturation well log true resistivity MacLaurin series

Global economies and infrastructure still depend heavily on petroleum-based products. Despite significant initiatives aimed at transitioning to renewable energy, the oil and gas sector continues to play a key role in shaping both the global economy and political landscape. Organizations like the U.S. Energy Information Administration, the U.S. Geological Survey, and the BP Statistical Review of World Energy have gathered extensive data reflecting this ongoing reliance. Oil reserves are not uniformly distributed across the globe. The Middle East holds the majority of the world's confirmed reserves, followed by countries such as United States and the Canada, as well as regions in Latin America, Africa, and the former Soviet states. Hydrocarbon deposits of a basin, or even part of it, led to the concept of an oil province that is mainly based on the analysis of geological setting. The defining of a petroleum system or province considers several criteria: geographic criteria (especially the extent and volume of rocks of interest); geological criteria (type of basin and its classification, stratigraphy) and petroleum criteria (potential and volume of discoveries, type of reservoir). After classifying giant oil fields according to basin and tectonic setting, several conclusions were drawn and a hierarchy was established: passive continental margins facing large ocean basins host of about 31% of giant deposits; continental rifts and overlying sag basins contain about 30% of the world's largest oil fields; the final collision belts between two continents form major basin that contains for approximately 24% of global giant fields; and continental arcs at convergent plate boundary, strike-slip systems, and subduction margins together host 15% of the world's giant fields. Looking ahead, the direction of oil exploration will be influenced not only by the quantity and type of resources available in the mentioned areas, but also by geopolitical dynamics and technological advances. Improved seismic imaging and detailed reservoir analysis are expected to play a greater role, especially in the development of unconventional resources such as tight oil, tight gas and shale formations. Romania can be considered the second largest oil producer and the third largest gas producer in the EU. Most known oil and gas fields in Romania have reached maturity, but the exploration of deeper structures has led to several recent discoveries. Current research techniques based on high-resolution seismic images correlated with a complex geophysical well investigation are expected to reveal new hydrocarbon accumulations both onshore areas (in orogenic or foreland type basins) and offshore in the western Black Sea basin. In order to have a clear picture of the development directions for oil and gas fields, this study analyzed data and statistics provided by specialized institutions and literature, synthesizing them in a clear and suggestive way possible according to the diagram below. The paper represents a first step in guiding future exploration efforts.

Granulometric analysis conducted on four samples from the same Holocene depth (covering 1363.73 sqm) reveals strong evidence for a braided fluvial environment, consistent with channel bar, levee, and floodplain deposition. Upon analysis, statistics reveal significant spatial heterogeneity: mean grain sizes range from 0.124 to 0.226 mm, while standard deviations (0.161–0.212 mm) reflect variable sorting. Kurtosis spans from 0.717 to 2.99, with higher values indicating well-sorted, peaked distributions from low-energy suspended settling (levee/floodplain) and lower values marking broader, mixed sorting in active channel bars. Positive folk skewness and diverse uniformity coefficients further point to episodic fluctuations in hydraulic flow and rapid sediment pulses. The coexistence of fine and coarse fractions and contrasting sorting regimes – supported by the absence of marine influence in the Holocene – confirms alternating energy and sediment supply typical of a braided river. These textural signatures underpin a gross depositional environment map, highlighting dynamic channel migration and nuanced fluvial architecture.