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Updated: Jul 7, 2026
07:58
Data Processing Methods for 3D Seismic Imaging of Subsurface Volcanoes: Applications to the Tarim Flood Basalt
Published on: August 7, 2017
High-resolution surface-wave tomography from ambient seismic noise.
Nikolai M Shapiro1, Michel Campillo, Laurent Stehly
1Center for Imaging the Earth's Interior, Department of Physics, University of Colorado at Boulder, Boulder, CO, USA. nshapiro@ciei.colorado.edu
Science (New York, N.Y.)
|March 12, 2005
Summary
Seismic noise analysis reveals California
Area of Science:
- Geophysics
- Seismology
- Earth Sciences
Background:
- Understanding the Earth's crustal structure is crucial for geological and seismic hazard assessments.
- Traditional seismic imaging methods can be limited in resolution and data acquisition.
Purpose of the Study:
- To develop and apply a novel method for imaging California's crustal structure.
- To utilize ambient seismic noise for high-resolution geophysical imaging.
Main Methods:
- Ambient seismic noise recorded by USArray stations in California was cross-correlated.
- Surface-wave group-speed measurements were obtained for interstation paths.
- Tomographic images of California's geological units were constructed using these measurements.
Main Results:
- Hundreds of short-period surface-wave group-speed measurements were generated.
- Tomographic images clearly delineated major geological units.
- Low-speed anomalies correlated with sedimentary basins; high-speed anomalies correlated with mountain range cores.
Conclusions:
- Cross-correlation of ambient seismic noise provides effective surface-wave data for crustal imaging.
- This technique enhances the resolution and fidelity of crustal images compared to conventional methods.
- The study successfully mapped principal geological units of California using seismic noise.
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