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Shin J.,Korea Institute of Geoscience and Mineral Resources | Shin C.,Seoul National University | Calandra H.,TOTAL Exploration and Production
Journal of Applied Geophysics | Year: 2016

Laplace-domain waveform inversion reconstructs long-wavelength subsurface models by using the zero-frequency component of damped seismic signals. Despite the computational advantages of Laplace-domain waveform inversion over conventional frequency-domain waveform inversion, an acoustic assumption and an iterative matrix solver have been used to invert 3D marine datasets to mitigate the intensive computing cost. In this study, we develop a Laplace-domain waveform modeling and inversion algorithm for 3D acoustic-elastic coupled media by using a parallel sparse direct solver library (MUltifrontal Massively Parallel Solver, MUMPS). We precisely simulate a real marine environment by coupling the 3D acoustic and elastic wave equations with the proper boundary condition at the fluid-solid interface. In addition, we can extract the elastic properties of the Earth below the sea bottom from the recorded acoustic pressure datasets. As a matrix solver, the parallel sparse direct solver is used to factorize the non-symmetric impedance matrix in a distributed memory architecture and rapidly solve the wave field for a number of shots by using the lower and upper matrix factors. Using both synthetic datasets and real datasets obtained by a 3D wide azimuth survey, the long-wavelength component of the P-wave and S-wave velocity models is reconstructed and the proposed modeling and inversion algorithm are verified. A cluster of 80 CPU cores is used for this study. © 2016 Elsevier B.V. Source


Yan R.,University of California at Santa Cruz | Guan H.,TOTAL Exploration and Production | Xie X.-B.,University of California at Santa Cruz | Wu R.-S.,University of California at Santa Cruz
Geophysics | Year: 2014

Due to incomplete aperture coverage and complex overburden structures, the migration process cannot provide a trueamplitude image even though a true-amplitude propagator is used. Amplitude compensation based on source-side illumination ignores the aperture effects on the receiver side, and it may fail to recover the true-reflection/scattering strength of a geologic structure from the image. The structural dip largely controls if the wave incident on the structure can be reflected back and received by the acquisition aperture, so it should be taken into account in removing the acquisition effects from the migration image. We derived a dip-angle domain amplitude correction from the resolution theory. The stacked migration image created by reverse time migration was decomposed into common dip images, which were compensated individually by the corresponding amplitude correction factor. Then, we summed up the corrected images to form a final image. To construct the amplitude correction factor, we generated a monofrequency Green's function at the shot/geophone location and further decomposed it into incident/scattered plane waves. They were combined based on Snell's law to construct correction factors for different dips. The final amplitude correction factor was formed by visiting all the shotgeophone pairs in the observation system. We devised efficient algorithms to make the amplitude correction more practical. We evaluated two numerical experiments, a five-layer model and the SEG/EAGE salt model, in which the amplitude correction led to a scalar/pressure image with an amplitude better matching the true impedance contrasts of subsurface structures, especially in areas with steep dips and in subsalt regions. © 2014 Society of Exploration Geophysicists. Source


Bordmann V.,TOTAL Exploration and Production
Society of Petroleum Engineers - SPE International Conference on Health, Safety and Environment in Oil and Gas Exploration and Production 2010 | Year: 2010

With Host Countries stepping up their demands and expectations in terms of local content, defining its perimeter and boundaries has created some confusion among the industry. It becomes a challenge for IOCs/NOCs to agree on its definition, perimeter, and hence on its indicators to measure it. This proposed paper will present a possible perimeter for local content development initiatives and suggest key performance indicators. Local content -aimed at enhancing skills, developing suppliers and infrastructures of Host Countries in connection with field development and production projects -now occupies a predominant place in the oil & gas producing countries. Usually measured as a percentage of investment, of man hours, of weight of equipment manufactured, or of jobs created and industrial bases used, local content concerns industrial capacities as much as human resources. IOC/NOC operators therefore act simultaneously on multiple levers to obtain progress on this front: training the country's technicians and managers, hiring local staff, stimulating the networks of SME and pre-qualifying local companies. This proposed paper is based on a definition of local content applied by TOTAL for its oil & gas development projects. It is also based on a methodology applied by TOTAL to measure local content for its oil & gas development projects. The main application of the information provided in the proposed paper is to provide the industry with one way of defining and measuring local content, which is not always formalised. Case studies will not be presented in this paper, only the methodology. Indeed, when it comes to benchmark local content of different oil & gas development project, it is rarely possible to do it, due to different definition / perimeters, and absence of local content indicators. Copyright 2010, Society of Petroleum Engineers. Source


Bordmann V.,TOTAL Exploration and Production | Obembe O.,Total E and P Nigeria | Longuet L.,Total E and P Indonesia
Society of Petroleum Engineers - SPE International Conference on Health, Safety and Environment in Oil and Gas Exploration and Production 2010 | Year: 2010

With Host Countries stepping up their demands and expectations in terms of local content, identifying and developing local capacity building initiatives becomes paramount for IOC/NOCs. This paper presents a process for identifying and developing local content initiatives, in order to achieve challenging local content development objectives and hence increase the acceptability of IOC/NOC operators. Local content -aimed at enhancing skills, developing suppliers and infrastructures of Host Countries in connection with oil & gas field development and production projects -now occupies a predominant place in the oil & gas producing countries. In a competitive context, local content becomes an important - not to say essential - criterion in securing new permit awards or obtaining approval for oil & gas field development plans. It appears paramount to build up a strong industrial fabric and have qualified manpower and contractors. It is all the more important that after the appraisal-development phases, the operator then requires skilled local / national personnel to produce the oil and/or gas fields for a several decades. This paper describes the process and illustrates it with case studies, i.e. best practices in identifying and developing local capacity building initiatives. These case studies mainly highlight education initiatives and innovative supplier development initiatives, the latter being suppliers of goods but also suppliers of highly technical services like front end engineering and design. This paper is based on best practices applied in the category of Corporate Social Responsibility. Illustrative data include case studies and lessons learnt from local capacity building initiatives implemented in various countries, mainly on the African continent (Nigeria), in Asia (Indonesia) and also worldwide through a specific higher education initiative. The main application of the information provided in this paper is to help IOC/NOC operators to build local content development initiatives, in both education and supplier development. Copyright 2010, Society of Petroleum Engineers. Source


Turlan F.,TOTAL Exploration and Production | Audibert-Hayet A.,TOTAL Exploration and Production
Society of Petroleum Engineers - Arctic Technology Conference 2012 | Year: 2012

TOTAL Exploration & Production has been active in cold environments since 1970 (i.e. drilling in the Arctic Islands in Canada) and has been operating the Russian Kharyaga field since 1999. For its first experiences in those challenging conditions, TOTAL applied its internal rules and specifications that were not aimed at this kind of environments but to "classic" prospects, the main assets being in the Guinea Golf, in the North Sea, the Middle East and in South East Asia. As the prospects and TOTAL'S portfolio have developed in areas where temperatures are below -15°C, such as Kashagan field in Kazakhstan or Yamal in Russia, an "Extreme Cold" taskforce was put together several years ago. The aim is to gather feedbacks from the past and to centralize the Research & Development activities to look for innovative solutions for the future and on-going projects. The workgroup is organized around several panels, one of those being the Health and Safety aspects for the operations in Extreme Cold conditions. From partnership through JIPs, internal research and workshops with affiliates (mainly in Norway, Russia or Canada), and projects teams, it has been decided to produce internal guidelines in order to define and harmonize the practices, acknowledging that each field has its own meteorological constraints, and to gather the results from the multiple actions carried out by TOTAL headquarters or affiliates. The methodology and the risk analysis performed to obtain a common technical basis will be here presented. Copyright 2012, Offshore Technology Conference. Source

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