Shale & Tight Rock
Where Geophysics and Engineering Collide
Source, Reservoir and Seal – Challenges and Solutions
Shale and tight rocks, also commonly referred to as unconventional reservoirs, are a class of rocks whose mineralogies, fine-grained textures, low porosity, and permeability do not permit the ready flow of fluids. These rocks are therefore ideal as barriers to fluid flow in the subsurface and provide excellent trapping mechanisms for oil and gas or stored fluids such as carbon dioxide. Where organic rich, under favorable burial conditions they may form hydrocarbon source rocks. They also have considerable potential as hydrocarbon reservoirs, and as a result, special drilling, stimulation, and completion technologies and approaches are deployed to tap into the vast resource potential these rocks offer.
Shale and tight rocks come in myriad forms – high clay content, organic rich and relatively ductile, such as the oil prone and producing Wolfcamp reservoirs in the U.S. Permian basin or the quartz-carbonate and relatively brittle siltstones of the gas bearing Montney formation, Canada. Regardless of location and type, these rocks all require a detailed understanding of their petrophysical, elastic and mechanical properties in order to be effectively interpreted from seismic and assessed as potential hydrocarbon reservoirs or as barriers or containers for geological disposal projects.
Shale and tight rock operations require sophisticated software evaluation tools to analyze rock properties, ensuring the implementation is optimal for drilling and completion processes. Enhancing accuracy in predicted Stimulated Rock Volume (SRV) is essential for maximizing productivity, alongside refining the interpretation of azimuthal seismic data to unveil fracture orientation and intensity. Reducing risks associated with containment, identifying the most productive zones, and safely disposing of waste-water and other by-products are all paramount to safe, compliant, and efficient operations in these plays.
Understand containment risks, characterize rock and completion quality, and optimize drilling operations
- Improve stimulation design through probabilistic mineralogy and organic content determination for future mechanical characterization studies
- Identify zones of fracturing in wells and correlate to seismic and producing intervals using image log interpretation
- Calibrate well and seismic data using advanced methods for land and marine conventional and multi-component seismic datasets
- Improve seismic interpretation accuracy through Rock Physics Modeling to connect elastic properties to shale and tight reservoir rock properties
- Avoid drilling hazards and identify production potential through automated fracture detection and extraction from seismic attributes
- Reduce risk associated with anomalous pressures in deep basins through regional velocity modeling and pore pressure prediction
- Increase production in naturally fractured sections through detailed textural and azimuthal anisotropic velocity analysis to determine fracture density and orientation
- Predict presence and distribution of highly productive intervals through anisotropic elastic inversion
- Identify containment risks associated with petrophysical and structural changes within sealing units / barriers
- Improve drilling performance and accuracy through development of an integrated petrophysical and mechanical model delivered on the engineering grid
- Reduce drilling costs by leveraging seismic information to optimize development areas in fast-paced onshore drilling campaigns
- Optimize pad placement and well bore trajectories to avoid drilling hazards and reduce bit changes
- Manage anti-collision uncertainty in locations where you have multiple boreholes from a single pad.
- Visualize and understand collision risks against existing and proposed well paths
- Improve wellbore stability and drilling window estimates through the incorporation of anisotropic analysis of wells and seismic data
- Increase the well EUR by strategic well placement in zones of favorable production characteristics that reduce the costs associated with hydraulic stimulation