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Subsurface Stress Inversion Modeling Using Linear Elasticity : Sensivity Analysis and Applications Mostfa Lejri

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Subsurface Stress Inversion Modeling Using Linear Elasticity : Sensivity Analysis and Applications Mostfa Lejri Subsurface stress inversion modeling using linear elasticity : sensivity analysis and applications Mostfa Lejri To cite this version: Mostfa Lejri. Subsurface stress inversion modeling using linear elasticity : sensivity analysis and applications. Geophysics [physics.geo-ph]. Université de Montpellier, 2015. English. tel-01324110 HAL Id: tel-01324110 https://hal.archives-ouvertes.fr/tel-01324110 Submitted on 31 May 2016 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Délivré par l’Université de Montpellier Préparée au sein de l’école doctorale SIBAGHE Et de l’équipe de recherche BASSINS Spécialité : GEOSCIENCES Présentée par LEJRI Mostfa (Mustapha) SUBSURFACE STRESS INVERSION MODELING USING LINEAR ELASTICITY: SENSITIVITY ANALYSIS AND APPLICATIONS Soutenance prévue le 02 Juillet 2015 devant le jury composé de : Dr. Roger Soliva, Université Montpellier Directeur de thèse Dr. Laurent Maerten, Schlumberger Co-Directeur Dr. Frantz Maerten, Schlumberger Co-Directeur Pr. Olivier Lacombe, Université Paris VI Rapporteur Pr. Jean Pierre Gratier, Université de Grenoble Rapporteur Pr. Rodolphe Cattin, Université Montpellier Examinateur Dr. Bertrand Gauthier, Total Examinateur Dr. Bernard Célérier, Université Montpellier Examinateur Avant-propos Cette thèse a été co-financée par une bourse CIFRE (ANRT) et l’entreprise Schlumberger sous l’égide du laboratoire de géosciences de l’université de Montpellier. Elle s’est déroulée en majeure partie au sein des locaux de Schlumberger MpTC à Montpellier. Le présent manuscrit est constitué de quatre articles scientifiques. Le premier est publié dans la revue Tectonophysics, le second est en préparation pour la revue Tectonophysics. Les troisième et quatrième articles sont en préparation pour Structural geology et le journal de l’AAPG. Par conséquent, le format des chapitres est présenté en anglais sous la forme d’articles scientifiques. Remerciements Mon experience pendant cette thèse CIFRE au sein de Schlumberger a été intellectuellement stimulante et enrichissante au dela des espérances. Cette thèse n’aurait pas été possible sans l’implication et la contribution intellectuelle de plusieurs personnes que ce soit au sein de Schlumberger, de l’université de Montpellier ou dans mon entourage. Je tiens d’abord à remercier très chaleureusement mes directeurs de thèse Laurent Maerten qui m’a transmis son savoir sur la géologie structurale et m’a appris, à travers son oeuil expert et une pédagogie exceptionnelle, à raisonner et écrire en tant que scientifique, et Frantz Maerten qui, par son génie et avec beaucoup d’humour, m’a donné goût à la programmation et à la mécanique des failles. Ils ont su m’épauler durant ces années, et m’ont insufflé leur enthousiasme, leur vision et leur passion pour la géologie, la modélisation numérique et la géomécanique. Je remercie au même titre Roger Soliva qui m’a transmis sa passion de la géologie structurale, il a été pour moi un exemple de rigeur dans le travail et m’a guidé tout au long de cette aventure. Plus que des mentors vous avez été de véritables amis. Je voudrais spécialement remercier Emmanuel Malvesin, qui tout au long de ces années a été un ami, d’un conseil avisé, et un motivateur incontournable, “la fine fleur…” ainsi que Jean Pierre Joonnekindt qui a été un grand soutient, et Nader Salman, un co-leader exceptionnel. Je remercie biensur Alex Wilson, qui a suivi tout mon parcours et oeuvré pour mon integration au sein de Schlumberger. Un grand merci aux collègues à Schlumberger MpTC, et plus particulièrement, Stéphane Bonassies et Christelle Guilermou qui ont oeuvré afin que ma these se déroule dans les meilleures conditions possibles. J’en profite également pour remercier toutes les personnes qui m’ont soutenu de près ou de loin (dans le désordre): Claire Maerten, Aloïse Chabert pour sa bonne humeur constante, Joan Mouba , Pauline Cornard, Thomas Laverne pour les discussion passionnées, Ezzdine Benabou pour son aide qui a été critique à la dernière minute, Berangère Guerry et Sarah Macaud pour leurs encouragements, Martin Neumeyer pour sa passion de géologie et les discussions enrichissantes, Naouel Arbi pour son aide et ses encouragements depuis mon arrive à Schlumberger, Marie LeFranc, Saad Kisra, Fabrice, Paxi, Phil Resor, Mathieu, Terje, Jimmy, Michael, David, Illike, Gayana, Thibault Cavailhes, Marine Dalmasso… Bertrand Gauthier qui a été d’un grand conseil et pour sa confiance en moi lors du workshop à Total, Olivier Lacombe pour m’avoir permis d’approfondir mes connaissances et m’avoir acceuilli à L’EGU, Bernard Célérier pour ses conseils et corrections post-soutenance, et Romain Plateaux pour son enthousiasme et sa lecture constructive du manuscrit… vous avez tous été la et je garde de vous un souvenir impérissable. Merci à Ali Mehez, Fares Bouhlila et Adlène Mallem et qui ont été des frères pour moi durant ces années d’études. Un immense merci à Axelle Riou qui a été présente pour moi à chaque instant. Merci également à Sandrine Riou et Michel Portant, votre presence a été pour moi très importante. Et bien sûr, un grand merci à Marie-France Roch pour son assistance depuis le Master et aux equipes du laboratoire géosciences et particulièrement Michel Serannes pour son suivi et son intransigence. Enfin je remercie les membres de ma famille qui m’ont encouragé depuis le plus jeune age dans ma passion pour les sciences et en particulier mon père Mohamed Lamine Lejri et ma mère Nejia Lejri à qui je dédie ce travail. Lejri Mostfa, Juillet 2015 « If i have seen further than others, it is by standing upon the shoulders of giants » Isaac Newton Table of Contents Extended abstract 1 General introduction 5 1. Essence of the thesis 5 2. How are the fractures modeled in the Oil & gas industry? 6 2.1. Existing techniques 6 2.2. Techniques based on geomechanics 7 3. Faults and Fractures 9 3.1. Faults, fault systems and stress field 10 3.2. Fault genesis and tectonic regimes 12 3.3. Fault reactivation 14 3.4. Fault sliding friction 16 3.5. Fractures classification and stress field 18 3.6. Fractures related to faulting 19 3.6.1. Fracture genetically associated to faulting 19 3.6.2. Fracture not genetically associated to faulting 20 4. How to recover paleostresses? 22 4.1. Paleostress estimation using Wallace & Bott type methods 23 The Wallace (1951) and Bott (1959) hypothesis 23 4.1.1. The stress ratio (R) 24 4.1.2. The forward problem 25 4.1.3. Stress inversion problem 26 4.1.4. Stress inversion using slip data 28 4.1.5. Stress inversion using focal mechanisms 31 4.1.6. Stress inversion using calcite twins 34 4.2. Polyphase tectonic events 36 4.2.1. The polyphase data problem 36 4.2.2. Existing methods to separate tectonic phases 37 4.3. Methods based on geomechanics 40 4.3.1. Least squares formulation (Kaven et al., 2011) 40 4.3.2. iBem3D (Maerten et al., 2014) 40 5. Methods (after Maerten et al., 2014) 41 5.1. iBem3D - iterative boundary elements method 42 5.1.1. Far field stress/strain 44 5.1.2. Research applications 44 5.1.3. Industry and engineering applications 50 5.1.4. Latest enhancements 55 5.2. BEM-based stress inversion method 57 5.2.1. Principle of superposition 59 5.2.2. Real time computation 60 5.2.3. Method of Resolution 61 5.2.4. Cost functions 62 5.2.5. Tectonic stress domain 64 6. Problematics of the thesis: 65 References 67 CHAPTER I: Paleostress inversion: A multi-parametric geomechanical evaluation of the Wallace-Bott assumptions 95 Abstract 95 1. Introduction 96 2. Method 99 2.1. Numerical tool 99 2.2. Fault geometry 100 2.3. Tectonic stress 103 2.3. Fault friction 104 2.4. Fault fluid pressure 105 2.5. Traction free surface of the Earth 105 2.6. Poisson’s ratio 106 2.7. Non-tested parameters 107 2.8. Mean misfit angle calculation and domain representation 107 3. Results 111 3.1. Effect of fault geometry 111 3.1.1. Single planar fault 111 3.1.2. Intersecting faults 112 3.1.3. Sinusoidal faults 115 3.2. Effect of the traction free surface of the Earth 116 3.3. Effect of Poisson’s ratio 117 3.4. Effect of fault friction 118 3.5. Effect of fault fluid pressure 120 4. Discussion 121 4.1. Fault geometry 121 4.2. Traction free surface 125 4.3. Poisson's ratio 125 4.4. Fault friction 126 4.5. Fault fluid pressure 126 4.6. Complementary study 126 5. Conclusions 129 Acknowledgements 131 References 132 CHAPTER II: Accuracy evaluation of both Wallace-Bott and BEM-based paleostress inversion methods 143 Abstract 143 1. Introduction 144 2. Method 147 2.1. Stress inversion methods 147 2.2. Fault geometry 149 2.3. Tectonic stress 150 2.4. Sliding friction 151 2.5. Data sampling 152 2.6. Analysis procedure 152 3. Analyses 155 3.1. Relationship between 흎 and 휟 155 3.2. Sliding friction effect 158 3.3. Sampling effect 161 4. Chimney Rock case study 162 4.1. Geologic setting and previous models 163 4.2. Fault model configuration 167 4.3. Stress inversions and sampling methodology 168 4.4. Stress inversions accuracy prediction domain 172 5. Discussion 173 5.1. Relationship between 흎 and 휟 173 5.2.
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