Microseismic Processing, Interpretation, and Applications

Introduction to Microseismic Monitoring and Fundamentals.

• Overview
• Fundamentals
• Monitoring systems and configurations
• Event Location: basics and principles
• Advanced processing
• Examples

Microseismic Interpretation, Quality Assurance of Events Data, and Qualitative Interpretation Methods.

1. Overview of microseismic interpretation, applications, and objectives

2. Historical perspective of fracturing theory and microseismic measurements

• Early studies – M-Site, Cotton Valley, Barnett Shale and implications on the understanding of fracture geometry
• Images of hydraulic fractures (mine-back and outcrops)
• Current understanding of the significance of microseismic events

3. Quality control of microseismic event for interpretation

• Magnitude versus distance
• Signal quality parameters
• Uncertainty
• Monitoring configurations – special considerations for detection and uncertainty
• Surface microseismic
• Time synchronization with treatment data
• Waveform measurements and display

4. Qualitative interpretation methods and applications

• Dimension and azimuths
• Stimulated volume estimates
• Time-dependent behavior
• Case history 1 – Comparison of fracture geometry from two different pumping schedule designs

5. Discussion topic – What is ESV/SRV and its relevance in interpretations of fracture geometry and well performance?

Sources of Microseismic Events during Fracturing, Failure Mechanisms, Source Parameters and Source Wave Radiation Patterns.

1. Waveforms and spectral analysis

• Expanded description of microseismic event source mechanism properties
• Spectral analysis to determine source wave mechanisms (Brune model)
• Source parameters – moment, moment-magnitude, radius, and stress drop

2. Event magnitudes and interpretation

• Event magnitude distributions (b-value)
• Interpretation of b-values and event magnitude catalogs
• Case history 1 re-visited – Interpretation of event magnitudes and distributions

3. Seismic moment and applications

• Explanation of seismic moment parameter and its relationship to event magnitudes
• Cumulative moment versus ESV/SRV as a qualitative evaluation tool
• Cumulative moment versus time
• Cumulative moment versus depth
• Case history 2 – Induced stresses and effects on microseismic response in a single-well completion

4. Source wave radiation patterns and source wave amplitudes

• Failure mechanisms and source-wave radiation patterns
• P/S Amplitude ratio
• Hypothetical modeling of amplitude ratios in strike-slip and dip-slip failures
• Qualitative interpretations of fracture complexity using amplitude ratios
• Case history 3 – Interpretation of failure mechanisms using surface and downhole microseismic data

5. Introduction to moment-tensor inversion, visualization, and interpretation

• Inversion process and monitoring requirements
• Moment-tensor visualization – Beachballs, Hough plots, E-O-S visualization
• Interpretation of the moment-tensor inversion

6. Discussion topic – How does what has been learned so far bring value to completion and hydraulic fracture treatment design?

Data Integration and Interpretation Applications

1. Data integration and geological context

• External factors that can influence microseismic responses
• Formation tops and surfaces
• Mechanical earth models
• Visualization and interpretation in a well-described geological model

2. Interpretations for fracture treatment and completion design optimization in vertical wells

• Fracture dimensions and azimuths
• Height containment and staging design in vertical wells
• Well spacing considerations

3. Interpretations for fracture treatment and completion design optimization in vertical wells

• Fracture orientation and well path
• Well spacing considerations and interference with offset wells
• Well landing point evaluations
• Induced stresses and effects on fracture geometry in pad completions
• Special considerations when reservoir pressure depletion is present

4. Discussion topic – Can microseismic data determine proppant placement and predict well performance?

Integrated Microseismic Interpretation and Fracture Modeling.

• Case history of fracture modeling and microseismic measurements in a vertical well (conventional reservoir)
• Case history of fracture modeling and microseismic measurements in a horizontal well (unconventional reservoir)
• Wrap-up and conclusion