COURSE LENGTH (days): 4
COURSE DESCRIPTION: Sample topic from the class: "The Importance of Natural-Fracture Type in Controlling Reservoir Permeability"
Participants of this course will receive a copy of Atlas of Natural and Induced Fractures in Core, which offers a reference for the interpretation of natural and induced fractures in cores. An invaluable reference that helps geologists recognize and differentiate the many types of natural fractures, induced fractures and artefacts found in cores. The natural and induced fracture data contained in cores provides a wealth of information once they are recognized and properly interpreted. This resource provides a much-needed tool to help with the accurate interpretation of these cores. The authors include the information needed to identify different fracture types as well as the criteria for distinguishing between the types of fractures. The atlas shows how to recognize non-fracture artefacts in a core since many of them provide other types of useful information. In addition, the text’s illustrated structures combined with their basic interpretations are designed to be primary building blocks of a complete fracture assessment and analysis. The authors show how to recognize and correctly interpret these building blocks to ensure that subsequent analyses, interpretations, and modeling efforts regarding fracture-controlled reservoir permeability are valid. Presented in full color throughout, this comprehensive reference is written for geologists charged with interpreting fracture-controlled permeability systems in reservoirs as well as for students or other scientists who need to develop the skills to accurately interpret the natural and induced fractures in cores.
- Shear and extension fractures have significantly different effects on reservoir interconnectivity, drainage anisotropy, and stimulation potential.
- Fracture permeability can be dynamic, changing with changes in the in situ stresses during production. These dynamic effects are more prevalent in unconventional reservoirs.
- Different lithologies (shale, sandstone, and carbonates) have different mechanical properties and are prone to different types of fractures with different permeability effects.
- Fracture effects on a reservoir depend on the ratio between fracture and matrix permeability. Therefore, fractures have a much greater effect on permeability in unconventional reservoirs vs conventional reservoirs.
- Image logs are important tools for fracture characterization that need to be calibrated.
- Induced fractures in a core record the in situ stress conditions, but must not be mistaken for the natural fractures that control permeability.
- Interaction of natural fractures and hydraulic stimulation fractures.