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Model Selection and Uniqueness Analysis for Reservoir History MatchingRafiee, Mohammad Mohsen 28 March 2011 (has links) (PDF)
“History matching” (model calibration, parameter identification) is an established method for determination of representative reservoir properties such as permeability, porosity, relative permeability and fault transmissibility from a measured production history; however the uniqueness of selected model is always a challenge in a successful history matching.
Up to now, the uniqueness of history matching results in practice can be assessed only after individual and technical experience and/or by repeating history matching with different reservoir models (different sets of parameters as the starting guess).
The present study has been used the stochastical theory of Kullback & Leibler (K-L) and its further development by Akaike (AIC) for the first time to solve the uniqueness problem in reservoir engineering. In addition - based on the AIC principle and the principle of parsimony - a penalty term for OF has been empirically formulated regarding geoscientific and technical considerations. Finally a new formulation (Penalized Objective Function, POF) has been developed for model selection in reservoir history matching and has been tested successfully in a North German gas field. / „History Matching“ (Modell-Kalibrierung, Parameter Identifikation) ist eine bewährte Methode zur Bestimmung repräsentativer Reservoireigenschaften, wie Permeabilität, Porosität, relative Permeabilitätsfunktionen und Störungs-Transmissibilitäten aus einer gemessenen Produktionsgeschichte (history).
Bis heute kann die Eindeutigkeit der identifizierten Parameter in der Praxis nicht konstruktiv nachgewiesen werden. Die Resultate eines History-Match können nur nach individueller Erfahrung und/oder durch vielmalige History-Match-Versuche mit verschiedenen Reservoirmodellen (verschiedenen Parametersätzen als Startposition) auf ihre Eindeutigkeit bewertet werden.
Die vorliegende Studie hat die im Reservoir Engineering erstmals eingesetzte stochastische Theorie von Kullback & Leibler (K-L) und ihre Weiterentwicklung nach Akaike (AIC) als Basis für die Bewertung des Eindeutigkeitsproblems genutzt. Schließlich wurde das AIC-Prinzip als empirischer Strafterm aus geowissenschaftlichen und technischen Überlegungen formuliert. Der neu formulierte Strafterm (Penalized Objective Function, POF) wurde für das History Matching eines norddeutschen Erdgasfeldes erfolgreich getestet.
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Model Selection and Uniqueness Analysis for Reservoir History MatchingRafiee, Mohammad Mohsen 28 January 2011 (has links)
“History matching” (model calibration, parameter identification) is an established method for determination of representative reservoir properties such as permeability, porosity, relative permeability and fault transmissibility from a measured production history; however the uniqueness of selected model is always a challenge in a successful history matching.
Up to now, the uniqueness of history matching results in practice can be assessed only after individual and technical experience and/or by repeating history matching with different reservoir models (different sets of parameters as the starting guess).
The present study has been used the stochastical theory of Kullback & Leibler (K-L) and its further development by Akaike (AIC) for the first time to solve the uniqueness problem in reservoir engineering. In addition - based on the AIC principle and the principle of parsimony - a penalty term for OF has been empirically formulated regarding geoscientific and technical considerations. Finally a new formulation (Penalized Objective Function, POF) has been developed for model selection in reservoir history matching and has been tested successfully in a North German gas field. / „History Matching“ (Modell-Kalibrierung, Parameter Identifikation) ist eine bewährte Methode zur Bestimmung repräsentativer Reservoireigenschaften, wie Permeabilität, Porosität, relative Permeabilitätsfunktionen und Störungs-Transmissibilitäten aus einer gemessenen Produktionsgeschichte (history).
Bis heute kann die Eindeutigkeit der identifizierten Parameter in der Praxis nicht konstruktiv nachgewiesen werden. Die Resultate eines History-Match können nur nach individueller Erfahrung und/oder durch vielmalige History-Match-Versuche mit verschiedenen Reservoirmodellen (verschiedenen Parametersätzen als Startposition) auf ihre Eindeutigkeit bewertet werden.
Die vorliegende Studie hat die im Reservoir Engineering erstmals eingesetzte stochastische Theorie von Kullback & Leibler (K-L) und ihre Weiterentwicklung nach Akaike (AIC) als Basis für die Bewertung des Eindeutigkeitsproblems genutzt. Schließlich wurde das AIC-Prinzip als empirischer Strafterm aus geowissenschaftlichen und technischen Überlegungen formuliert. Der neu formulierte Strafterm (Penalized Objective Function, POF) wurde für das History Matching eines norddeutschen Erdgasfeldes erfolgreich getestet.
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History matching sensitivity investigations and forecasting for low matrix porosity, permeability and highly fractured carbonate reservoir to optimize oil production in Kurdistan RegionHakim, Sarko Hussen Hakim 10 January 2019 (has links)
Increasing of the oil recovery is an essential task of the reservoir engineers. Many highly fractured carbonate reservoirs with low matrix porosity and low matrix permeability in the world have been depleted with low ultimate recovery due to the improper management. To obtain higher oil recovery and an optimum oil production, a three dimensional geological model for the reservoir is needed. The reservoir model should be calibrated via the history matching process which makes the model reliable for forecasting and development planning. An investigation has been carried out to find the most sensitive parameter which affects the matching between the real production data and the simulated production data. After the calibration of the model, some prediction scenarios have been run to realize the future performance of the reservoir. Three wells have been suggested and included in the simulation as producers in some prediction cases and as gas injectors in another other case. The results show that the three producers with low production rate will assist in increasing the recovery and by converting those to gas injectors will assist more especially when the oil production rate is higher. An oil field in Kurdistan region has been selected for this research.
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The Use of Mediation and Mediative Elements to Improve the Integration of the Human Factor in Risk Assessments in Order to Enhance the Safety in the International Oil and Gas Industry / Die Anwendung der Mediation und mediativer Elemente zur besseren Einbeziehung des Faktors „Mensch“ in die Risikobeurteilung zur Erhöhung der Sicherheit in der internationalen Öl- und GasindustrieKinzel, Holger 19 July 2017 (has links) (PDF)
The work of an engineer is closely intertwined with safety. An engineer’s perception of the “safety” task is traditionally inherent in his or her design. However, in the technical world most machines and systems designed by engineers contain a human element, which engineers have to consider in their work.
In the oil and gas upstream industry – especially drilling, production and workover operations – petroleum engineers (including drilling and production engineers) are responsible not only for design but also for operational and organizational aspects. The human factor becomes more important in complex offshore operations. Incorporating safety into a sys-tem design requires identifying, analyzing and evaluating risks and ensuring that any not accounted for are taken into consideration. This process requires communication among everyone involved in the process. Analysis of accidents in the oil and gas industry shows that often a lack of that communication led to incident triggering events.
In this thesis, the author proposes a novel communication model that improves this exchange of information and supposedly makes the process of risk assessment more effective. In addition, the new model also incorporates factors such as emotions, feelings, needs and imagination into the risk assessment process. This broadens the information base for the risk identification and analysis and creates an atmosphere of psychological ownership for the stakeholders in the process, which leads to a perceived safety climate in the organization where the new model is applied.
The innovative communication or consultation model, as it is also referred to in risk assessments, is based on a structured process used in conflict resolution called mediation. Mediation is an alternative conflict resolution process that is centered on mutual under-standing and listening to each other’s needs. The process is composed of elements that characterize it. These elements of mediation are used to assess other communication processes and to develop new communication models. The application of the elements of mediation and the safety-mediation consultation into the risk assessment process enables this process to be enhanced with human factors such as emotions, feelings, intuition and imagination. The inclusion of all stakeholders creates psychological ownership, improves communication, enables organizational learning and expands the knowledge base for risk analysis.
The applicability of the safety-mediation consultation process for a human factor-based risk assessment is presented and tested using illustrative examples and field cases from the international oil and gas industry. Possible concerns and limitations are also discussed.
This thesis shows that mediation and elements of the mediation process can be applied to improve communication in the international oil and gas industry. This is facilitated by educated safety mediators, who help the petroleum engineer and operational crew on a drilling rig to achieve a better understanding by ensuring that they hear and fully register each other’s needs.
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The Use of Mediation and Mediative Elements to Improve the Integration of the Human Factor in Risk Assessments in Order to Enhance the Safety in the International Oil and Gas IndustryKinzel, Holger 26 June 2017 (has links)
The work of an engineer is closely intertwined with safety. An engineer’s perception of the “safety” task is traditionally inherent in his or her design. However, in the technical world most machines and systems designed by engineers contain a human element, which engineers have to consider in their work.
In the oil and gas upstream industry – especially drilling, production and workover operations – petroleum engineers (including drilling and production engineers) are responsible not only for design but also for operational and organizational aspects. The human factor becomes more important in complex offshore operations. Incorporating safety into a sys-tem design requires identifying, analyzing and evaluating risks and ensuring that any not accounted for are taken into consideration. This process requires communication among everyone involved in the process. Analysis of accidents in the oil and gas industry shows that often a lack of that communication led to incident triggering events.
In this thesis, the author proposes a novel communication model that improves this exchange of information and supposedly makes the process of risk assessment more effective. In addition, the new model also incorporates factors such as emotions, feelings, needs and imagination into the risk assessment process. This broadens the information base for the risk identification and analysis and creates an atmosphere of psychological ownership for the stakeholders in the process, which leads to a perceived safety climate in the organization where the new model is applied.
The innovative communication or consultation model, as it is also referred to in risk assessments, is based on a structured process used in conflict resolution called mediation. Mediation is an alternative conflict resolution process that is centered on mutual under-standing and listening to each other’s needs. The process is composed of elements that characterize it. These elements of mediation are used to assess other communication processes and to develop new communication models. The application of the elements of mediation and the safety-mediation consultation into the risk assessment process enables this process to be enhanced with human factors such as emotions, feelings, intuition and imagination. The inclusion of all stakeholders creates psychological ownership, improves communication, enables organizational learning and expands the knowledge base for risk analysis.
The applicability of the safety-mediation consultation process for a human factor-based risk assessment is presented and tested using illustrative examples and field cases from the international oil and gas industry. Possible concerns and limitations are also discussed.
This thesis shows that mediation and elements of the mediation process can be applied to improve communication in the international oil and gas industry. This is facilitated by educated safety mediators, who help the petroleum engineer and operational crew on a drilling rig to achieve a better understanding by ensuring that they hear and fully register each other’s needs.
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The influence of physico-chemical surface properties and morphological and topological pore space properties on trapping (CCS) and recovery efficiency (EOR): a micromodel visualization studyGolmohammadi, Saeed 26 October 2023 (has links)
We theoretically and experimentally investigate the impact of pore space structure, wettability, and surface roughness on the displacement front, trapping, and sweeping efficiency at low capillary numbers. The microstructure of (i) 2D geologically-realistic media (2D natural sand and sandstone), (ii) a topological 3D-2D-transformation (2D sand analog), and (iii) geometrically representative media (Delaunay Triangulation) were studied over a wide range of wettability from water-wet to oil-wet systems provided by using various fluid-pairs. We observed the transition (compact to fractal) in the displacement front caused by local instabilities identified by Cieplak and Robbins. The trapping efficiency of 2D natural microstructures showed a non-monotonous dependency on wettability, whereas a crossover from no trapping to maximal trapping was observed in 2D patterns of circular grains. For the first time, we compared identical experimental microstructures with simulation, capturing the key elements of the invasion process. We demonstrated that corner flows occur particularly in low-porosity media, where the smaller grain-grain distance hindered the corner-flow bridging. These insights could improve the CO2 geological storage and Enhanced Oil Recovery processes.
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Kurz- und langfristige Angebotskurven für Rohöl und die Konsequenzen für den MarktSchlothmann, Daniel 20 April 2016 (has links) (PDF)
In dieser Arbeit wurden Angebotskurven für 22 bedeutende Ölförderländer ermittelt und anschließend zu globalen Angebotskurven aggregiert. Gemäß den ermittelten Angebotskurven sind nahezu alle gegenwärtig in der Förderphase befindlichen Ölprojekte in den Untersuchungsländern auch beim aktuellen Ölpreis von 35 bis 40 US-$ je Barrel unter Berücksichtigung der kurzfristigen Grenzkosten rentabel. Sollte der Ölpreis jedoch in den kommenden Jahren auf diesem Niveau verharren, wird es bis zum Jahr 2024 zu einem Angebotsengpass auf dem globalen Ölmarkt kommen, da zur Deckung der zukünftigen Nachfrage die Erschließung kostenintensiver, unkonventioneller Lagerstätten und von Lagerstätten in tiefen und sehr tiefen Gewässern notwendig ist. Damit es bis zum Jahr 2024 nicht zu einem solchen Angebotsengpass kommt, ist gemäß des ermittelten langfristigen Marktgleichgewichts ein Ölpreis von mindestens 80 (2014er) US-$ je Barrel notwendig.
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Kurz- und langfristige Angebotskurven für Rohöl und die Konsequenzen für den MarktSchlothmann, Daniel 08 March 2016 (has links)
In dieser Arbeit wurden Angebotskurven für 22 bedeutende Ölförderländer ermittelt und anschließend zu globalen Angebotskurven aggregiert. Gemäß den ermittelten Angebotskurven sind nahezu alle gegenwärtig in der Förderphase befindlichen Ölprojekte in den Untersuchungsländern auch beim aktuellen Ölpreis von 35 bis 40 US-$ je Barrel unter Berücksichtigung der kurzfristigen Grenzkosten rentabel. Sollte der Ölpreis jedoch in den kommenden Jahren auf diesem Niveau verharren, wird es bis zum Jahr 2024 zu einem Angebotsengpass auf dem globalen Ölmarkt kommen, da zur Deckung der zukünftigen Nachfrage die Erschließung kostenintensiver, unkonventioneller Lagerstätten und von Lagerstätten in tiefen und sehr tiefen Gewässern notwendig ist. Damit es bis zum Jahr 2024 nicht zu einem solchen Angebotsengpass kommt, ist gemäß des ermittelten langfristigen Marktgleichgewichts ein Ölpreis von mindestens 80 (2014er) US-$ je Barrel notwendig.:1. Einleitung
2. Rohöl - Eine naturwissenschaftliche Einführung
3. Charakteristika von Rohölprojekten
4. Historie der Ölindustrie
5. Ökonomik von Rohölprojekten
6. Fallstudien zu den bedeutendsten Förderländern
7. Ermittlung regionaler und globaler Angebotskurven
8. Zusammenfassung
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