Fault Geomechanics and Carbon Dioxide Leakage Applied to Geological Storage: FY07 Quarterly and Summary Reports

[摘要] Safe and permanent storage of carbon dioxide in geologic reservoirs is critical to geologic sequestration. The objective of this study is to quantify the conditions under which a general (simulated) fault network and a specific (field case) fault network will fail and leak carbon dioxide out of a reservoir. Faults present a potential fast-path for CO{sub 2} leakage from reservoirs to the surface. They also represent potential induced seismicity hazards. It is important to have improved quantitative understandings of the processes that trigger activity on faults and the risks they present. Fortunately, the conditions under which leakage along faults is induced can be predicted and quantified given the fault geometry, reservoir pressure, an in-situ stress tensor. We proposed to expand the current capabilities of fault threshold characterization and apply that capability to a site where is CO{sub 2} injection is active or planned. Specifically, we proposed to use a combination of discrete/explicit and continuum/implicit codes to provide constrain the conditions of fault failure. After minor enhancements of LLNL's existing codes (e.g., LDEC), we would create a 3D synthetic model of a common configuration (e.g., a faulted dome). During these steps, we will identify a field site where the necessary information is available and where the operators are willing to share the necessary information. We would then execute an analysis specific to the field case. The primary products by quarter are: 1Q--Identification of likely field case; 2Q--Functioning prototype fault model; 3Q--Execution of fault-slip/migration calculation for synthetic case; and 4Q--Begin simulation of fault-slip/migration calculation for field system. It is worth noting that due to the continuing resolution, we did not receive any funds until 3Q, and did not receive >65% of the support until 4Q. That said, we were still able to meet all of our milestones for FY07 on time and on budget.

[发布日期] 2007-11-02

[学科分类] 地球科学(综合)

[关键词] CARBON DIOXIDE;CONFIGURATION;GEOMETRY;RESERVOIR PRESSURE;RESOLUTION;SEISMICITY;SIMULATION;STORAGE