Project Overview
Objective
The Society of Exploration Geophysicists (SEG) deployed 64 SmartSolo IGU-16 1C seismic nodes in South Central South Dakota to characterize ambient seismic noise. This study aimed to:
- Evaluate the robustness of passive seismic methods.
- Enhance future projects’ success by minimizing risks through reliable noise data analysis.
Deployment Details
- Grid Layout: Nodes were deployed on a 100-meter grid.
- Continuous Recording: The equipment recorded data non-stop for 7 days.
- Efficiency: The deployment was completed in just 3 hours, highlighting high operational efficiency.
Key Findings
The project showcased several insights derived from the SmartSolo seismic nodes:
- Enhanced Frequency Range: Passive data extended the frequency spectrum’s lower limit from 5.5 Hz (active data) to 2.5 Hz, improving shear wave velocity (MASW) modeling for deeper layers.
- Beamforming Analysis: Indicated an isotropic signal distribution across a 1-5 Hz frequency range. Sources included road traffic and the Missouri River.
- Cross-Correlation Stacking: Demonstrated good dispersion, validating the development of a robust surface wave model for shear wave velocity (Vs).
Additional Observations
- 1D Vs Model:
- Revealed a three-layer structure consistent with well control data.
- Confirmed depths to bedrock and basement align with known geological benchmarks.
- 3D Depth Inversion Results:
- Identified velocity anomalies in glacial sections.
- Correlated anomalies with topographic and seismic expressions of a buried glacial valley.
Benefits of SmartSolo Equipment
SmartSolo seismic nodes proved essential to the survey’s success due to their:
- Operational Efficiency: Quick and straightforward deployment even in challenging environments.
- Data Quality: Reliable recordings enabled detailed seismic modeling.
- Passive Seismic Applications: Enhanced subsurface characterization using ambient noise sources.
Conclusion
The results confirm that passive seismic methods, supported by SmartSolo nodes, significantly contribute to subsurface characterization. These advancements highlight the role of innovative seismic technology in enabling effective and efficient geophysical studies.
Article source: Society of Exploration Geophysicists (SEG) James Mika
Nodes and data harvesting were provided by Seismic Equipment Specialists, LLC (Ross Kennedy & Boyse Harris).