Submarine Debris flow Project Proposal to Force August 2018/v1.02

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1 Submarine Debris flow Project Proposal to Force August 2018/v1.02 Summary The main objective of the Submarine Debris Flow study is to implement the concept of debris flow in the MassFlow3DÔ code as an extension to the turbidity currents - transport, erosion and deposition mechanisms, currently in use. MassFlow3D is a state-of-the-art simulation tool for sediment gravity flows based on full 3D flow deterministic modelling. MassFlow3D models sediment transport, erosion and deposition and is used to give objective turbidite facies and related depositional patterns, and an indication of the reservoir quality of the deposits. For exploration, MassFlow3D is used to de-risk the reservoir presence, define traps and geometry and improve the paleo-bathymetry. It is well suited as a tool integrated in the current work flow for exploration assessment. MassFlow3D is validated for turbidity currents through several research projects and analysis of field cases over several years. The program is now in commercial use for de-risking of reservoir presence and quality. Turbidity currents are sediment flows that contain up to approximately 30% particles. The flows containing > 30% particle load is often referred to as Debris or Hybrid Flows. With such high sediment concentrations, the support mechanisms will be dominated by grain to grain interaction, agglomeration, fluid escape and turbulence. By including debris flow in the revised code of MassFlow3D TM, the program will be able to handle the two dominating types of depositional processes for hydrocarbon reservoirs in medium deep and deep marine setting. A pre-project to identify potential rheological models for debris flow and laboratory/field data to validate the model is in progress and will be concluded by September The main scope of the project is to identify and implement the rheological characteristics of debris flow in the MassFlow3DÔ code and validate this towards available laboratory and field data. The project will be run by GeoGravity Flow AS with sub-tasks assigned to the University of Bergen, The Arctic University of Norway, University of Bangor and Flow Science. The project is planned for years, with commencement in January The costs are estimated to 3 million NOK per year, a total of 8 million NOK. It will be applied for funding from the Research Council of Norway, The Petromax program (Innovation chapter). This is expected to cover minimum 40% of the project costs. The rest of the funding is sought from Industry, with 4-5 participants, i.e million NOK total for each participant. 1

2 Proposal Objective The main objective of the Submarine Debris Flow study is to implement the concept of debris flow in the MassFlow3DÔ code as an extension to the turbidity currents - transport, erosion and deposition mechanisms, currently in use. Pre-project A pre-project is in progress and will be completed in September It is addressing the following: Review models for rheology for debris flow (Non-Newtonian models) and test these in the current version of MassFlow3D Define the work to adapt these models to the Flow3D core code and the MassFlow3D preprocessor. Identify sources of data to evaluate the simulation code based on existing field data, laboratory studies and geological conceptual models. The main conclusions are ready, but the ongoing activity may still result in minor modifications to the scope of the main study. MassFlow3D and the relevance for exploration on the NCS MassFlow3D is a state-of-the-art simulation tool for sediment gravity flows based on full 3D flow deterministic modelling. MassFlow3D models sediment transport, erosion and deposition and is used to give objective turbidite facies and related depositional patterns, and an indication of the reservoir quality of the deposits. Stratigraphic traps may be predicted in relation to simulated bypass and pinch-out of the sandy gravity flows. The program is based on fundamental flow equations. The flow properties are determined by particle concentration and grain size distribution of the source sand and the velocities by the slopes on the seafloor. The geometry determines the settling patterns, and the program will respond to changes in the geometry, also what is caused by the sediment flow itself, e.g. spillover. The shear in the turbulent flow will give mixing/separation of particles, and this determines the properties of the settled particles (porosity, connectivity). The fundamental approach behind the program makes it possible to scale up from small scale studies (e.g. laboratory) to full scale field conditions. For exploration, MassFlow3D is used to de-risk the reservoir presence, define traps and geometry and improve the paleo-bathymetry. It is well suited as a tool integrated in the current work flow for exploration assessment to address the probability of reservoir presence and expected properties, the depositional geometry related to possible stratigraphic traps, and give the most likely geological model and paleo-topography. To handle uncertainties in the input data, a scenario-based approach is used. Input data are varied in an iterative process to establish the most promising geological model and input parameters. 2

3 MassFlow3D is validated for turbidity currents through several research projects and analysis of field cases over several years. The program is now in commercial use for de-risking of reservoir presence and quality as a service run by GeoGravity Flow AS. On a longer term, the plans are to license the program to oil companies and service companies. Turbidite and debris flow Turbidity currents are sediment flows that contain up to approximately 30% particles. The flows containing > 30% particle load is often referred to as Debris or Hybrid Flows. With such high sediment concentrations, the support mechanisms will be dominated by grain to grain interaction, agglomeration, fluid escape and turbulence. This will influence the flow and the final sediment extension and quality. Clay represents a special challenge since both the particle load and the ionic properties influence on the flow behaviour, run-out and deposition. Provisions for rheology models associated with debris flow is part of the core code of MassFlow3DÔ, but must be detailed and validated towards laboratory and field data, and be included in preprocessing software used to define a run. This modelling will require access to physical data about the behaviour of debris flow systems. Sources of such data have been identified during the pre-project in Application potential of revised MassFlow3D code Nearly all hydrocarbon reservoir sediments deposited in deeper environment than shallow marine setting have been deposited by sediment gravity flows, of which turbidity currents and debris flows dominate. By including debris flow in the revised code of MassFlow3D TM, the program will be able to handle the two dominating types of depositional processes for hydrocarbon reservoirs in medium deep and deep marine setting. This will be of great value in hydrocarbon exploration and development, as well as for the academia and the society in general (slope stability and safety). Scope of Work The main scope of the project is to identify and implement the rheological characteristics of debris flow in the MassFlow3DÔ code and validate this towards available laboratory and field data. This will include the following main tasks: 1. Implement the debris flow rheology in the MassFlow3D TM code. Test by simulating several cases with simple planar slope configuration and a wide range of sediment-water mixtures and slope inclinations. Implement the modifications in the current interface of MassFlow3DÔ. 2. Prepare lab and field data for evaluation, identify cases to run. 3. Run defined cases and compare/validate the results towards: a. Laboratory data (University of Bangor). 3

4 b. Field data, mainly from Storegga and West Barents Sea (University of Bergen, Arctic University of Norway). 4. Modify code a work flow according to results. 5. Make comparative simulations for a range of the most common substrate topographical configurations, e.g., substrate morphological obstacles, bedrock canyon confinement and channel bend all for a range of flow sizes and the relative size of the topographical relief. One of the main sources for validation are the extensive studies of Storegga done in the 1980s. The University of Bergen were active in these studies and have access to central data that will be made available for this project. It will also be considered to supplement existing field data by analysing e.g. stored cores from Storegga to give a more detailed picture of the facies of the identified sediment flows (University of Bergen). Interfaced with this project, a study of the basin infilling in the Western Barents Sea will be done by the Arctic University of Norway. The aim of this study is to better understand the source areas for Cenozoic sediment accumulation in this area. Existing studies (recent Ph.D.) will be evaluated using MassFlow3D to simulate the basin infilling. In addition to the data provided for the Debris Flow project, the results of this study will be beneficial for the petroleum industry to predict the Cenozoic sand distribution in the Western Barents Sea. The detailed scope will be finalised when an ongoing pre-study is completed in September 2018 and will be adjusted accordingly. Schedule Planned commencement is in January 2019, and completion during Q3/Q A tentative schedule for the main tasks is shown below. Milestones: Code modified and tested: Dec 2019 First lab case for simulations defined: June 2019 Field cases defined/setup for modelling and simulation: Dec

5 Costs and funding The costs are estimated to approximately: 3 mill NOK/year, a total of 8 mill. NOK for the entire project. Funding is sought through the Research Council of Norway and industry contribution. An application to The Research Council s Petromax program will be submitted in October 2018, aimed at the Innovation chapter. An application will also be sent to Skattefunn. The total funding from these two programs can be max 50% of the project costs, we assume between 40 and 50. The remaining budget is sought through industry contribution with 4 6 participants each contributing between 800 and 1 mill NOK each over 3 years. The costs are made up of the following: Personnel costs Computer costs External costs (e.g. modification of Flow3D core code) Travel costs The Arctic University of Norway have already secured partial funding for their part, this program will include one-year funding for a post doc, and some operational costs. Business Model and Organisation The project will be run by GeoGravity Flow AS as project owner and main contractor. The University of Bergen and the Arctic University of Norway will run their own tasks in the project as subcontractors, with defined interaction with the project. The arrangement with University of Bangor is not yet formalised. It will depend on the extent of supplementary laboratory studies needed for the project and will be clarified during the pre-project. The project will be organised with a steering committee with members from all participating companies. The steering committee will meet regularly, at least twice a year. Once a year, it is planned to arrange a workshop, if possible in connection with a field trip to a relevant outcrop site and/or laboratory facility. Deliverables of project and for sponsors With its focus on innovation, the main deliverable of the project will be the updated MassFlow3D code. This will be used by GeoGravity Flow AS in services to the oil industry and be part of the package that will be licensed to the industry in the future. The academic institutions will provide data for model validation, but will also extend the scope of completed studies to supplement the data: Prepare data from Storegga (University of Bergen), supplementary analysis of cores. Western Barents Sea (Arctic University of Norway) Lab studies from University of Bangor, supplementary tests? Relevant findings from these studies will be published separately in scientific literature. 5

6 Through the steering committee and at the workshops it will be possible for the participants to address topics from their own operation. As the project proceeds, it may be possible to include some of these topics in the scope. Through the participation, sponsors will get a first-hand insight into the MassFlow3D code and the data behind the validation. In parallel to the project, GeoGravity Flow AS will develop a revised graphical user interface to the program. As this work proceeds, it will be possible for the participating companies to get hands on experience using the code for internal purposes. 6