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Source Rock Characterization and Petroleum Generation Modelling of the Levant Basin, Onshore-Offshore Lebanon: an Integrated Approach

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Source rock characterization and petroleum generation modelling of the Levant Basin, onshore-offshore Lebanon: An integrated approach Von der Fakultät für Georessourcen und Materialtechnik der Rheinisch -Westfälischen Technischen Hochschule Aachen zur Erlangung des akademischen Grades eines Doktors der Naturwissenschaften genehmigte Dissertation vorgelegt von M.Sc. Samer Bou Daher aus Beirut, Libanon Berichter: Univ.-Prof. Dr. rer. nat. Ralf Littke Univ.-Prof. Dr. Rudy Swennen Tag der mündlichen Prüfung: 07. März 2016 Diese Dissertation ist auf den Internetseiten der Hochschulbibliothek online verfügbar “There are no limits when you are surrounded by people who believe in you, or by people whose expectations are not set by the short-sighted attitudes of society, or by people who help to open doors of opportunity, not close them.” Neil deGrasse Tyson, The Sky is Not the Limit: Adventures of an Urban Astrophysicist I dedicate this work to my family ii Acknowledgment My PhD journey would not have been possible without the support, guidance, and help of many people and institutes. I would like to start by thanking the German Academic Exchange Service (DAAD) and Maersk Oil for funding this project. A good supervision plays a major role in the success of any project. And I have had the privilege of receiving a great supervision. I thank my supervisor Prof. Dr. Ralf Littke for his continuous support, advice, and trust. I thank my co-supervisor Dr. Fadi Nader whose positive energy, enthusiasm, and continuous support have been an invaluable asset in this project and a precious source of motivation for me. Whether on the professional or on the personal level, it has been a pleasure and an honour to be their student and to learn from them. I thank Prof. Dr. Harald Strauss, for preparation, measurement, and discussion of organic carbon isotope data. I thank Dr. Sven Sindern for his help in producing the XRF data. I thank Dr. Carla Müller for the biostratigraphic data and for her great company and valuable discussions in the field. I thank Dr. Nicolas Hawie for his help and fruitful discussions. I thank the crew of the institute of geology and geochemistry of petroleum and coal at RWTH Aachen who became like a family to me and was always welcoming, supportive, informative, and amusing. Special thanks to Olga Schefler for her administrative super powers. I thank the IFPEN teams at the departments of geology and geochemistry who have welcomed me as a guest for 5 months and were always available for assistance and discussions, particularly Fadi Nader, who has given me the opportunity to be at IFPEN, Bernard Carpentier, Mathieu Ducros, and Pauline Michel for their technical support and expertise. I thank Isabelle Moretti (GDF Suez) and other anonymous reviewers for their valuable comments which improved the published manuscripts. iii I thank BeicipFranlab for providing a TemisFlowTM software license. I thank the Cimenterie Nationale S.A.L. for granting access to their well cores and providing assistance in the quarry in Chekka. Special thanks go to Mr. Ahmed Hoteit. I thank Mr. Nabil Abou Dehen for his generosity and for providing the local information needed in the field in Hasbayya. I thank the Lebanese ministry of energy and water (Petroleum Administration) for providing permissions and access. To my friends who have supported me to pursue this challenging dream and my new friends that I made along the way, I cherish all the time we spent together camping, hiking, mountain biking, climbing, travelling, board gaming, kayaking, cooking, eating, partying, laughing, drinking, and much more….. I thank you for being part of my life. Finally, I would like to express my deepest appreciation and gratitude to my family for their unconditional love and support. Without them I would not have been here today. iv Preface The idea of this PhD thesis came as a result of new data that became available in the last decade and that gave rise to new scientific questions in the complicated east Mediterranean region. Initiated, coordinated and co-supervised by Fadi Nader (IFPEN) three parallel PhD projects were launched in the years 2011-2012, among which was this project. The first launched project, conducted by Nicolas Hawie at University Paris 6 UPMC, tackled the geodynamic evolution and sedimentary filling of the Levant basin using 2D seismic data, detailed outcrop sedimentologic and biostratigraphic analysis, and forward stratigraphic modelling. The second launched project, conducted by Ramadan Ghalayini at University Paris 6 UPMC, tackled the structural evolution of the complex Cenozoic zone of the Levant Basin offshore Lebanon using 3D and 2D seismic data, as well as structural modelling. The third project, presented in this thesis, tackles the potential source rocks exposed along the eastern margin of the Levant basin, and analyses the thermal history of the study area and the evolution of potential petroleum systems onshore and offshore Lebanon using detailed geochemical and petrographic analysis on source rock samples, as well as 3D petroleum system modelling. Along with these projects, several master and bachelor projects were accomplished and another set of PhD theses were launched in 2014-2015 targeting the lithospheric dynamics of the Levant basin as well as the geodynamic and structural evolution of its western margin. All in all, this tremendous scientific and organizational effort lead to the establishment of the “Levant research group” which includes several European and international universities and research institutes and helps to create synergy between the various research projects. v Abstract This thesis consists of a combination of analytical and numerical modelling work on the east Mediterranean Levant basin which has in the last decade become a frontier hydrocarbon province. Several gas discoveries have been recorded in Miocene reservoirs offshore Israel and seismic data suggest promising prospective plays in deeper intervals throughout the basin. Source rock information and calibration points are hitherto scarce due to the lack of well data, especially in the offshore Lebanon part of the basin. Thus, this thesis provides a considerable contribution to the available geochemical data and thermal evolution of the study area. The analytical work consist of geochemical data from several potential source rocks, specifically Upper Cretaceous (Campanian – lower Maastrichtian), outcropping along the eastern margin of the Levant Basin onshore Lebanon. The Upper Cretaceous rock succession has shown very good source rock properties that have a kerogen type that varies laterally and vertically throughout the study area between Type II and Type IIS kerogen. Biomarker, kinetic, petrographic, and elemental data attribute this shift in kerogen type to iron deficiency and variable organic matter content, and suggest deposition of these source rocks under a high productivity zone mostly restricted to the shelf area. This depositional model implies a decrease in organic matter (OM) richness towards deeper and distal basinal areas, which in turn would be accompanied by a shift in bulk hydrocarbon generation kinetics to higher values due to oxidation of labile OM and a decrease in organic sulphur content. This trend is observed in HI values and measured bulk hydrocarbon generation kinetics of Upper Cretaceous source rocks with various OM content onshore Lebanon. The recorded lateral and vertical variations in the Upper Cretaceous (Campanian – lower Maastrichtian) suggest that the onset and the extent of the oil and gas window can vary considerably within the same source rock as a function of organofacies. Other source rocks that have been characterized in this thesis include the Upper Jurassic (Kimmeridgian), Lower Cretaceous (Neocomian), Cenomanian, Albian, and upper vi Paleocene. The Kimmeridgian, Neocomian, and Albian include Type III/IV kerogen with gas potential while the Cenomanian and upper Paleocene include type I and II/III with oil and gas potential. All analysed source rocks are thermally immature. The numerical modelling part consists of a large scale 3D thermal history and maturity model of the Levant basin, margin, and onshore Lebanon. The constructed model has been calibrated using the publically available data in addition to the data produced in this thesis. The model suggests the presence of several potential petroleum systems including an Upper Cretaceous- Oligo-Miocene biogenic and thermogenic system in the deep basin, a Jurassic-Cretaceous system along the margin, and a Permian-Triassic system in the onshore. Sensitivity analysis suggested an important effect of the depth of the lithospheric-asthenospheric boundary on the thermal history of the basin and showed that under any scenario, the thickness of the biogenic zone below the Messinian salt would vary between 700 and 1500 m in the deep basin offshore Lebanon. vii Zusammenfassung Die vorliegende Doktorarbeit beinhaltet eine Kombination aus analytischen Daten und numerischer Modellierung des ostmediterranen Levante Beckens, in welchem sich in der letzten Dekade eine große Explorationstätigkeit entwickelte. Vor der Küste Israels sind verschiedenste Gasfunde in miozänen Reservoiren gemacht worden; seismische Daten lassen weitere vielversprechende Lagerstätten in tieferen Gesteinsschichten des Beckens vermuten. Informationen über das Muttergestein und damit mögliche Kalibrationsdaten für numerische Modelle sind rar, da bisher kaum Daten aus Bohrungen existieren. Dies betrifft insbesondere
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