TY - JOUR A1 - Tella, Timothy O. A1 - Winterleitner, Gerd A1 - Morsilli, Michele A1 - Mutti, Maria T1 - Testing sea-level and carbonate production effects on stratal architecture of a distally steepened carbonate ramp (Upper Miocene, Menorca) BT - a 3D forward modelling approach JF - Sedimentary geology : international journal of applied and regional sedimentology N2 - Although distally steepened carbonate ramps have been studied by numerous researchers, the processes that control the development of these carbonate systems, including tectonics, differential carbonate production along the ramp profile, or antecedent physiography of the slopes, are an ongoing discussion. We use a stratigraphic forward model to test different hypotheses to unravel controls over distally steepened ramp development, referenced to the well-known Upper Miocene Menorca carbonate ramp (Spain). Sensitivity tests show that distally steepened ramps develop under complex interaction among accommodation, carbonate production and sediment transport parameters. Ramp slope initiation is favoured by still stands and falls of sea-level, in a setting with high-frequency sea-level fluctuations with amplitude between 20 m and 40 m. Low-frequency and higher amplitude sea-level fluctuations of about 115 m tend to form models with no significant slope development. The impact of antecedent slope on the geometry of ramps is determined by the paleoslope inclination, with flat to subhorizontal paleosurfaces resulting in ramps that mirror the antecedent slope. In contrast, steeper paleosurfaces tend to result in ramps with well-defined slopes. Our models, therefore, show that the ramp profile becomes more influenced by the depth constraints on the carbonate sediment producers than by the geometry of the underlying topography as the inclination of the paleosurface increases. The presented models also show that seagrass-dominated shallow carbonate production tends to result in steep slopes due to the low-transport characteristic imposed by seagrass trapping. This steepness can, however, be altered by the introduction of high transport sediment grains from deeper carbonate producers, which fill the slopes and more distal sections of the ramp profile. KW - Forward model KW - Distally steepened ramp KW - Sea-level fluctuation; KW - Sensitivity analysis KW - Sediment transport KW - Carbonate production KW - Grain KW - association Y1 - 2022 U6 - https://doi.org/10.1016/j.sedgeo.2022.106267 SN - 0037-0738 SN - 1879-0968 VL - 441 PB - Elsevier CY - Amsterdam [u.a.] ER - TY - JOUR A1 - Van der Looven, Thomas A1 - Winterleitner, Gerd A1 - Betzler, Christian A1 - Mutti, Maria T1 - A biotic perspective on the Oligo-Miocene evolution of the Maldives carbonate platform from forward stratigraphic modelling (Indian Ocean) JF - Marine and petroleum geology N2 - Forward stratigraphic modelling is a fast-developing modelling approach, used to test conceptual models, and predict stratigraphic architecture and depositional facies from basin to reservoir scales. Published subsurface applications demonstrate its added value by integrating multidisciplinary data as well as geological concepts into its constraints. When applied to carbonate depositional systems, composed of multiple sediment factories, the cooperating and interdependent production mechanisms remain poorly studied. By applying the technique to a well-studied section of the Maldives carbonate platform, a specific model design-adapted to the geological age and setting, and constrained by available data-sheds light on the interaction of its carbonate producers. The results yield a naturalistic depositional facies distribution and offer insight in the changing relationship between biotic communities during the platform evolution. After calibration, the reference model unequivocally links the formerly proposed genetic model to the seismostratigraphic architecture. Furthermore, the results show how environmental changes (seemingly of secondary impact compared to changes in physical accommodation in the stratigraphic record) can induce substantial fluctuations in carbonate production rates of biotic communities, affect the ecological accommodation, and thus impact the platform architecture. Therefore, it is crucial to treat carbonate production rates during periods of environmental change as variables with associated uncertainties in a forward stratigraphic model setup. KW - neogene KW - Maldives carbonate platform KW - forward stratigraphic modelling KW - sequence stratigraphy KW - carbonate production Y1 - 2022 U6 - https://doi.org/10.1016/j.marpetgeo.2022.105907 SN - 0264-8172 SN - 1873-4073 VL - 145 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Tawfik, Ahmed Y. A1 - Ondrak, Robert A1 - Winterleitner, Gerd A1 - Mutti, Maria T1 - Source rock evaluation and petroleum system modeling of the East Beni Suef Basin, north Eastern Desert, Egypt JF - Journal of African earth sciences N2 - This study deals with the East Beni Suef Basin (Eastern Desert, Egypt) and aims to evaluate the source-generative potential, reconstruct the burial and thermal history, examine the most influential parameters on thermal maturity modeling, and improve on the models already published for the West Beni Suef to ultimately formulate a complete picture of the whole basin evolution. Source rock evaluation was carried out based on TOC, Rock-Eval pyrolysis, and visual kerogen petrography analyses. Three kerogen types (II, II/III, and III) are distinguished in the East Beni Suef Basin, where the Abu Roash "F" Member acts as the main source rock with good to excellent source potential, oil-prone mainly type II kerogen, and immature to marginal maturity levels. The burial history shows four depositional and erosional phases linked with the tectonic evolution of the basin. A hiatus (due to erosion or non-deposition) has occurred during the Late Eocene-Oligocene in the East Beni Suef Basin, while the West Beni Suef Basin has continued subsiding. Sedimentation began later (Middle to Late Albian) with lower rates in the East Beni Suef Basin compared with the West Beni Suef Basin (Early Albian). The Abu Roash "F" source rock exists in the early oil window with a present-day transformation ratio of about 19% and 21% in the East and West Beni Suef Basin, respectively, while the Lower Kharita source rock, which is only recorded in the West Beni Suef Basin, has reached the late oil window with a present-day transformation ratio of about 70%. The magnitude of erosion and heat flow have proportional and mutual effects on thermal maturity. We present three possible scenarios of basin modeling in the East Beni Suef Basin concerning the erosion from the Apollonia and Dabaa formations. Results of this work can serve as a basis for subsequent 2D and/or 3D basin modeling, which are highly recommended to further investigate the petroleum system evolution of the Beni Suef Basin. KW - source rock evaluation KW - Kerogen petrography KW - basin modeling KW - sensitivity KW - analysis KW - Beni Suef Basin KW - Egypt Y1 - 2022 U6 - https://doi.org/10.1016/j.jafrearsci.2022.104575 SN - 1464-343X SN - 1879-1956 VL - 193 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Tella, Timothy Oluwatobi A1 - Winterleitner, Gerd A1 - Mutti, Maria T1 - Investigating the role of differential biotic production on carbonate geometries through stratigraphic forward modelling and sensitivity analysis BT - the Llucmajor example JF - Petroleum geoscience N2 - The geometry of carbonate platforms reflects the interaction of several factors. However, the impact of carbonate-producing organisms has been poorly investigated so far. This study applies stratigraphic forward modelling (SFM) and sensitivity analysis to examine, referenced to the Miocene Llucmajor Platform, the effect of changes of dominant biotic production in the oligophotic and euphotic zones on platform geometry. Our results show that the complex interplay of carbonate production rates, bathymetry and variations in accommodation space control the platform geometry. The main driver of progradation is the oligophotic production of rhodalgal sediments during the lowstands. This study demonstrates that platform geometry and internal architecture varies significantly according to the interaction of the predominant carbonate-producing biotas. The input parameters for this study are based on well-understood Miocene carbonate biotas with characteristic euphotic, oligophotic and photo-independent carbonate production in which it is crucial that each carbonate-producing class is modelled explicitly within the simulation run and not averaged with a single carbonate production-depth profile. This is important in subsurface exploration studies based on stratigraphic forward models where the overall platform geometry may be approximated through calibration runs, and constrained by seismic surveys and wellbores. However, the internal architecture is likely to be oversimplified without an in-depth understanding of the target carbonate system and a transfer to forward modelling parameters. Y1 - 2022 U6 - https://doi.org/10.1144/petgeo2021-053 SN - 1354-0793 SN - 2041-496X VL - 28 IS - 2 PB - Geological Soc. Publ. House CY - Bath ER - TY - JOUR A1 - Winterleitner, Gerd A1 - Schütz, F. A1 - Wenzlaff, Christian A1 - Huenges, Ernst T1 - The impact of reservoir heterogeneities on High-Temperature aquifer thermal energy storage systems BT - a case study from Northern Oman JF - Geothermics : an international journal of geothermal research and its applications N2 - We conducted a geoscientific feasibility study for the development of a high-temperature thermal aquifer energy storage system (HT-ATES) outside the capital of Muscat, northern Oman. The aquifer storage is part of a solar geothermal cooling project for the sustainable and continuous cooling of office buildings. The main concept is that excess solar energy will be stored in the subsurface through hot water injection and subsequently utilised as auxiliary energy source during peak demand times. The characterisation of aquifer heterogeneities is thus essential to predict subsurface thermal heat plume development and recovery efficiency of the storage system. We considered two aquifer systems as potential storage horizons, (i) a clastic-dominated alluvial fan system where individual channel systems in combination with diagenetic alterations constitute the main heterogeneities and (ii) a carbonate-dominated system represented by a homogenous layer-cake architecture. The feasibility study included a multidisciplinary approach from initial field work, geocellular reservoir modelling to finite element fluid flow and thermal modelling. Our results show that for the HT-ATES system, with a high frequency of injection and production cycles, heat loss mainly occurs due to heterogeneities in the permeability field of the aquifer in combination with buoyancy driven vertical fluid flow. An impermeable cap-rock is needed to keep the heat plume in place. Conductive heat loss is a minor issue. Highly complex heat plume geometries are apparent in the clastic channel system and ATES well planning is challenging due to the complex and interconnected high permeable channels. The carbonate sequence shows uniform plume geometries due to the layer cake architecture of the system and is tentatively more suitable for ATES development. Based on our findings we propose the general concept of HT-ATES traps, incorporating and building on expertise and knowledge from petroleum and reservoir geology regarding reservoir rocks and suitable trap&seal geometries. The concept can be used as guideline for future high-temperature aquifer storage exploration and development. KW - Aquifer thermal energy storage (ATES) KW - subsurface heterogeneities KW - fluid flow and thermal modelling KW - Oman Y1 - 2018 U6 - https://doi.org/10.1016/j.geothermics.2018.02.005 SN - 0375-6505 SN - 1879-3576 VL - 74 SP - 150 EP - 162 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Schütz, Felina A1 - Winterleitner, Gerd A1 - Huenges, Ernst T1 - Geothermal exploration in a sedimentary basin BT - new continuous temperature data and physical rock properties from northern Oman JF - Geothermal Energy N2 - The lateral and vertical temperature distribution in Oman is so far only poorly understood, particularly in the area between Muscat and the Batinah coast, which is the area of this study and which is composed of Cenozoic sediments developed as part of a foreland basin of the Makran Thrust Zone. Temperature logs (T-logs) were run and physical rock properties of the sediments were analyzed to understand the temperature distribution, thermal and hydraulic properties, and heat-transport processes within the sedimentary cover of northern Oman. An advective component is evident in the otherwise conduction-dominated geothermal play system, and is caused by both topography and density driven flow. Calculated temperature gradients (T-gradients) in two wells that represent conductive conditions are 18.7 and 19.5 °C km−1, corresponding to about 70–90 °C at 2000–3000 m depth. This indicates a geothermal potential that can be used for energy intensive applications like cooling or water desalinization. Sedimentation in the foreland basin was initiated after the obduction of the Semail Ophiolite in the late Campanian, and reflects the complex history of alternating periods of transgressive and regressive sequences with erosion of the Oman Mountains. Thermal and hydraulic parameters were analyzed of the basin’s heterogeneous clastic and carbonate sedimentary sequence. Surface heat-flow values of 46.4 and 47.9 mW m−2 were calculated from the T-logs and calculated thermal conductivity values in two wells. The results of this study serve as a starting point for assessing different geothermal applications that may be suitable for northern Oman. KW - Continuous temperature logging KW - Physical rock properties KW - Sedimentary basin KW - Geothermal applications in Oman Y1 - 2018 U6 - https://doi.org/10.1186/s40517-018-0091-6 SN - 2195-9706 VL - 6 IS - 1 PB - Springer CY - London ER - TY - JOUR A1 - Wenzlaff, Christian A1 - Winterleitner, Gerd A1 - Schutz, Felina T1 - Controlling parameters of a mono-well high-temperature aquifer thermal energy storage in porous media, northern Oman JF - Petroleum geoscience N2 - Aquifer thermal energy storage (ATES) as a complement to fluctuating renewable energy systems is a reliable technology to guarantee continuous energy supply for heating and air conditioning. We investigated a high-temperature (HT) mono-well system (c. 100 degrees C), where the well screens are separated vertically within the aquifer, as an alternative to conventional doublet ATES systems for an underground storage in northern Oman. We analysed the impact of thermal inference between injection and extraction well screens on the heat recovery factor (HRF) in order to define the optimal screento-screen distance for best possible systems efficiency. Two controlling interference parameters were considered: the vertical screen-to-screen distance and aquifer heterogeneities. The sensitivity study shows that with decreasing screen-to-screen distances, thermal interference increases storage performance. A turning point is reached if the screen distance is too close, causing either water breakthrough or negative thermal interference between the screens. Our simulations show that a combined heat plume with spherical geometry results in the highest heat recovery factors due to the lowest surface area to volume ratios. Thick aquifers for mono-well HT-ATES are thus not mandatory Our study shows that a HT-ATES mono-well system is a feasible storage design with high heat recovery factors for continuous cooling or heating purposes. Y1 - 2019 U6 - https://doi.org/10.1144/petgeo2018-104 SN - 1354-0793 VL - 25 IS - 3 SP - 337 EP - 349 PB - Geological Soc. Publ. House CY - Bath ER -