Time filter

Source Type


Tari G.,OMV Austria Exploration and Production GmbH | Poprawa P.,Energy Studies Institute | Krzywiec P.,Polish Academy of Sciences | Popadyuk I.,SPK Geoservice | Krezsek C.,Petrom
Society of Petroleum Engineers - European Unconventional Resources Conference and Exhibition 2014: Unlocking European Potential

The present day collage of various Silurian basin fragments in Central and Eastern Europe (CEE) is the result of several orogenic and rifting/drifting episodes. The proper paleogeographic reconstruction of a single, very large Silurian foredeep basin in the context of regional geology has a major impact on the ongoing unconventional shale gas exploration efforts in the region, including Poland, Ukraine, Romania and Moldova. The distal segments of a large Silurian foreland basin associated with the Caledonian collisional orogene, along the perimeter of the East European Craton, can be reasonably followed along strike from NW to SE, from Poland all the way to the Ukrainian Black Sea coast. The foredeep basin sequence onlaps to the NE the various pre-Silurian and crystalline basement units. The Silurian basin of the CEE is interpreted here as a pro-foreland basin, with short-lived (less than 15 m.y.) and extremely rapid (locally more than 1,500 m per m.y.!), accelerating subsidence histories recording a portion of the orogenic history of the broader Caledonian orogeny. Besides the typical subsidence curves and the very prominent onlap of successive Silurian lithostratigraphic units onto the craton, the flexural origin is also supported by the general lack of normal-faulting within the basin, contradicting some interpretations suggesting deposition on the extensional continental margin of the Rheic Ocean. The map-view distribution of the lithofacies within the basin, such as clastic turbidites in the southwestern perimeter of the basin, deepwater shales in the center and neritic carbonates on the northeastern foreland margin, is also consistent with the flexural basin interpretation. Source

Kosi W.,OMV Austria Exploration and Production GmbH | Tari G.,OMV Austria Exploration and Production GmbH | Nader F.H.,Lebanon Ministry of Energy and Water | Skiple C.,PGS | And 2 more authors.
Leading Edge

The Levant Basin is a deep-water basin in the eastern Mediterranean region. A large part of the basin contains a characteristic set of closely spaced normal faults, informally called the "piano key faults." These normal faults trending NW-SE have a fairly high-frequency map-view spacing of approximately 3-4 km on average and tens to hundreds of meters of interpreted throw. A large part of the pre-Messinian sedimentary strata is faulted, including the entire Miocene-to-Oligocene sequence. At depth, all the faults consistently die out at the same intra-Eocene detachment level. This stratigraphic level is interpreted to have a regionally developed shale sequence acting as the basal detachment surface for the piano key faults. The amount of throw on the individual faults appears to decrease toward the basin margin and the faults do not extend into the adjacent basins of the broader eastern Mediterranean area. © 2012 Society of Exploration Geophysicists. Source

Muller B.,Karlsruhe Institute of Technology | Heidbach O.,Karlsruhe Institute of Technology | Heidbach O.,German Research Center for Geosciences | Negut M.,Petrom | And 2 more authors.

The crustal stress pattern of Romania provides key insights into whether the Vrancea slab with its seismogenic volume between 70 and 175 km depth is still coupled to the crust and thus acts as a stress guide, or whether it is already in a state of detachment from the crust. Knowledge of the state of the slab under Vrancea is particularly critical because the slab attached to the crust can result in future strong earthquake occurrence in the crust and even in the currently aseismic zone between 40 km and 70 km depth, potentially causing severe damage. Our analysis of the contemporary tectonic stress observations in the context of potential stress sources and the comparison with numerical modelling shows that the crustal stress pattern in Romania is heterogeneous and does not contain a long wave-length stress pattern that would be expected if there is a strong present-day coupling between the subducted slab and the upper plate, or if lateral plate boundary forces would control the regional stress pattern. Therefore, we conclude that the crustal stress pattern of Romania is characterised by small differential horizontal stresses where local stress sources (third-order effects) are responsible for the observed heterogeneity of stress orientations and that the subducted slab under Vrancea is only weakly coupled to the crust. © 2009 Elsevier B.V. All rights reserved. Source

Behm M.,OMV Austria Exploration and Production GmbH | Egreteau A.,OMV Austria Exploration and Production GmbH | Afifi M.,Petrom | Ogliani F.,Schlumberger | Voskamp A.,Schlumberger
5th EAGE Passive Seismic Workshop: From Wish List to To-Do List

Enhanced oil recovery is routinely performed by water flooding in the Tazlau field in Eastern Romania. By the end of 2013, a borehole microseismic feasibility study was launched to gain better understanding of the producing reservoir behavior. Two wells were equipped with 8 geophones in approximately 1000 meters depths in two consecutive periods coinciding with the initiation of the injection phase. In the first well, a significant amount of microseismic events (2566) was recorded during 14 monitoring days, in contrast to a very small number of events (54) observed in the second well in the following 14-day period. This significant difference is related to the varying fracture density in the area and, to a lesser degree, to the amount of injected water. In general, event hypocenters can be located within distances of 600 meters from the monitoring well with sufficient accuracy, and their moment magnitudes range from -1.5 to -3.5. Fracture network characterization based on the microseismic pattern is supported by the analysis of fullbore formation imaging. The study provides new insight on potential water paths. We conclude that borehole microseismic monitoring appears as a promising and useful technique for steering water injection. Source

Minescu F.,Petroleum Gas University of Ploiesti | Popa C.,Petroleum Gas University of Ploiesti | Grecu D.,Petrom
Petroleum Science and Technology

Primary and secondary migrations are well defined terms in hydrocarbon reservoir genesis, as spontaneous hydrocarbon displacement from the source rock to the final trap. The fluid movement that occurs after reservoir abandonment defines the tertiary migration process. The result of the tertiary migration is a new saturation distribution within the reservoir and it is expected that in the most favorable cases, the production potential of some parts of the reservoir might be restored. The principles and factors involved in the tertiary migration process are examined and two successful production restarting projects in Romania are presented, as proof of the new concept effectiveness. Source

Discover hidden collaborations