Improving image accuracy of ambient noise data by temporary seismic arrays at different observation periods

Abstract

When using ambient noise data to invert velocity and anisotropic structures, the two-station inter-correlation method requires synchronous stations. If there are multiple temporary seismic arrays with different observation periods in the study area, the seismic arrays are usually used selectively. This paper takes the Sanjiang lateral collision zone as an example, and utilizes the ambient noise data of multiple temporary seismic arrays at different observation periods to improve the accuracy of regional velocity structure and anisotropy by anchoring permanent seismic stations. In this paper, notable enhancements in S-wave velocity and azimuthal anisotropy imaging accuracy are achieved by integrating data from three temporary seismic arrays (SJ-Array, SL-Array, and ChinArray-I) with the permanent seismic network. The imaging resolutions for the S-wave velocity and azimuthal anisotropy above 40 ​km are 0.4° ​× ​0.4° and 0.5° ​× ​0.5°, respectively. In the region of the most concentrated array coverage, the imaging resolution of S-wave velocity can reach 0.33° ​× ​0.33° at depths of less than 30 ​km. These findings underscore the significant improvement in deep structure imaging accuracy by the synergistic integration of ambient noise data from multiple temporary seismic arrays.