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Two main reservoirs are producing in Komombo Basin: the first one belongs to the C Member of the Six Hills Formation, and the second belongs to the Albian/Cenomanian cycle. The C Member reservoir lacks detailed studies. Therefore, a detailed study of this reservoir is needed. 3D geological reservoir modeling of the C Member reservoir can be a pertinent part of an overall strategy for the development of hydrocarbon fields in Komombo Basin. Five boreholes, three vertical seismic profiles and twenty 2D seismic reflection sections are integrated in Petrel™ modeling software for building 3D structural, facies and petrophysical models for the C Member reservoir. The constructed 3D structural model reveals the presence of two normal faults, in NW–SE and NE–SW directions. A detailed petrophysical evaluation was performed for the available wells. The resulted facies/petrophysical parameters are then used as input in the processes of facies and petrophysical modeling. The C Member reservoir exhibits thickness values ranging from about 91.5 to 426.5 m. The constructed 3D facies model of the studied reservoir depicts that the shale beds have the large probability distribution in the study area with the comparison of the sandstone and siltstone beds. The created 3D petrophysical models reveal that the C Member reservoir has a fair reservoir quality. This reservoir exhibits, generally, high water saturation values in most parts of the study area, while the hydrocarbon saturation is restricted to the depocenter of the basin.

The Albian/Cenomanian reservoir is one of the two main reservoirs composing the petroleum system in the Komombo Basin. However, these reservoirs have not previously been studied in detail. Therefore, a detailed study of the reservoirs is performed. Six boreholes, three vertical seismic profiles and twenty 2D seismic lines are integrated in the Petrel™ Schlumberger modeling software to build a 3D structural model for the Albian/Cenomanian reservoir. This model represents a framework for the subsequent 3D facies and petrophysical models of the studied reservoir. The interpretation of the created maps and 3D models shows two normal fault directions: NW–SE and NE–SW, where the NW–SE direction is dominant, creating a major half-graben system. Conventional well log analyses are performed for the available wells. The results are used in subsequent facies and petrophysical modeling. The thickness of the Albian/Cenomanian reservoir ranges from about 137 to 411.5 m. Petrographic analyses were conducted on two cores retrieved from the Albian/Cenomanian cycles covering the depth interval of 1323–1352 m in well AB-5. Most of the samples consist of quartz arenite and feldspathic arenite. The 3D facies model of the reservoir shows that the sandstone has a large probability distribution in the study area compared to the shale and siltstone. The 3D petrophysical models imply that the Albian/Cenomanian reservoir has good to very good reservoir quality. The main issue for the reservoir is the high water saturation values. In contrast, the hydrocarbon saturation is restricted to some parts of the basin.

Abu Gharadig Field lies in the central portion of Abu Gharadig Basin of the northern part of the Western Desert of Egypt, about 256 km west of Cairo. Abu Gharadig Basin is considered as an E-W trending intracratonic basin . The Upper Bahariya Member is a clayey reservoir and represents one of the Late Cretaceous units. There is a need for identifying whether the petrophysical parameters of this member are related to the facies changes or the present structures. Therefore, detailed structural and petrophysical studies are required. The structural configuration of the Upper Bahariya Member is studied in the present case and the results of this study will form the basis for future petrophysical studies. The present study includes the delineation of the main structural elements of the studied member within the study area. The aim of the present study was achieved through building a 3D structural model using Petrel™ Schlumberger Modeling software by integrating twenty 2D seismic sections with four digital well logs and a check-shot survey. The interpretation of the resulted model shows that the Upper Bahariya Member was folded into doubly plunging anticline with a gentle plunge to SW and a relatively steep plunge to NE. The fold was dissected by a series of normal faults trending E-W to NW-SE. The anticline is asymmetric and exhibits sigmoidal shape. The axis has mainly a NE-SW orientation and exhibits changing of this orientation in the NE part to be ENE-WSW and in the SW part to be also ENE-WSW, relating to the effect of a rotational stress. Growth faulting and thinning of the studied member at the crest of the anticline suggest the syn-sedimentary tectonics. Thus, these structures are related to the Late Cretaceous right-lateral shear which led to the opening of the North Atlantic.

Despite our understanding of the different mechanisms of man-made earthquakes, their short-term prediction and prevention is yet to be attained. In the present study, we propose an integrated four-step approach to predict and prevent man-made earthquakes or reduce their chance of occurrence. Our four-step approach includes locating the highly anomalous zones of microseismic emission (MSE) that result from the stress-deformed state inside a geological formation and often represents the “seismic nuclei” for impending earthquakes, monitoring the variations and dynamics of the anomalous MSE zones over a period of one lunar month, inducing a creep-discharging of the MSE zones using a vibroseis seismic source at the ground surface, and monitoring the same MSE zones following the creep-discharge to determine whether the stress-deformed state was released and the chance of potential earthquake occurrence has been eliminated or reduced. The proposed full four-step approach has never implemented at one single location. Nevertheless, these steps have been tested separately at different sites and have proven successful. We propose conducting the full four-step approach at various locations of potential man-made earthquake activities around the world including the state of Oklahoma in the USA.

The Upper Bahariya Member represents an argillaceous sandstone reservoir and it is one the Late Cretaceous units. There is a need for understanding the detailed facies and petrophysics of this member and identifying whether its petrophysical parameters are related to the facies changes or the present structures. Therefore, the present study aims at determining the facies and petrophysical characteristics of the Upper Bahariya Member and their distribution in the Abu Gharadig field. This field is located in the central portion of Abu Gharadig basin in the northern part of the Western Desert of Egypt. The available data for the present study includes four digital well logs, twenty 2D seismic sections and a checkshot survey. This is achieved through building the 3D facies and petrophysical models using Petrel™ Schlumberger Modeling software. These models were built on a predefined 3D stratigraphic and structural framework. The interpreted lithology of the Upper Bahariya Member is represented by sandstone cemented by argillaceous and/or calcareous materials, siltstone , shale and minor limestone inter-beds. A new lithofacies subdivision for the Upper Bahariya is introduced in the present study through the study area. This subdivision is represented by three lithofacies (an upper shale-silt-carbonate lithofacies, a middle sand-silt lithofacies and a lower shale-silt lithofacies). The Upper Bahariya Member is evaluated as a good quality reservoir and it exhibits rapid variations in the conditions of deposition, from continental fluvial to marine passing through the tidal flood plain conditions. The sandstone source is mainly from the southeast and southwest directions. The vertical and lateral changes of the different petrophysical parameters are directly related to vertical and lateral facies changes.

The Western Passive Continental Margin of the Indian Plate (WCMI) serves as an elegant laboratory for understanding the syn-sedimentary rift-drift tectonics preserving a variety of episodic structural deformations and complex sedimentary infill. Here we present a multidisciplinary study on Offshore Indus Basin (OIB) that is less investigated compared to adjacent marginal basins along WCMI. Reflection seismic, gravity, borehole, and biostratigraphic data have been used to reconstruct the tectono-sedimentary history of the Meso-Cenozoic succession in OIB. Seismic based dynamic stratigraphy helped in mapping seven different depositional sequences grounded on morpho-tectonic considerations. The seismic expression of these sequences provided an idea of the depositional styles with different tectonic episodes since rifting in Jurassic to basin inversion in Miocene continued to present time. The OIB initially filled from the north with the sediments rapidly prograding southwards. In general, the basin deepens in the central and northwestern part where the formations achieve maximum depths. The analysis of 3D structural models revealed that the region experienced poly-phase deformation from the Late Cretaceous to recent times that include steeply dipping normal faults, horst, and graben, half-graben, half-graben with growth faulting, flower structures, anticline, syncline, and uplift with an angular unconformity. The most remarkable tectonic activity happened at the Early Miocene and resulted in the reactivation of extensional faults into strike-slip faults giving rise to a spectacular structural inversion due to transform movement between Indian and Arabian Plates that continues to present day. The most predominant faults are oriented in S20°-50°E with azimuth as 120°–160° and the maximum dip angles are >80° in the southwest flank of the basin. The main fault trend is S20°E-N20°W and dip angles ranging between 40° and 80° and above. A thick crust and the Ocean-Continent Transition (OCT) is imaged with massive felsic, mafic, and ultramafic intrusions by the help of forward gravity modeling. An initial onset of syn-rift tectonic subsidence between 90 and 68 Ma with a post-rift general increase between 68 and 54 Ma is comprehended while two uplift events at ~40 Ma and ~18 Ma are documented through backstripping analysis. It is inferred that the region is rapidly under complex structural inversion with growing folding, faulting, and flowering structures. This study could help in explaining the unanswered reasons of structural complexities, depositional styles, and basin inversion along worldwide passive margins.