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Science Corner Nov 2025

by Helen Janiszewski (University of Hawai’i at Mānoa) and Joshua Russell (Syracuse University)

Nov 27, 2025

Ambient Noise Analyses at Broadband Ocean Bottom Seismometers: Data Quality and Transfer Function Corrections

Data collected by ocean-bottom seismometers (OBS) are essential for subduction zone research, but variability in noise properties and wave propagation can pose challenges. In a recent study, we characterize how ambient seismic noise recorded on broadband OBS varies across different marine settings, and evaluate under what circumstances transfer-function-based noise corrections improve data quality for imaging the solid Earth. Using deployments spanning a range of water depths, sediment conditions, and instrument designs, the study identifies the environmental factors that most strongly control the recoverability of surface-wave ambient noise signals commonly used in offshore crustal and upper-mantle imaging.

Our results show that transfer-function corrections are not universally beneficial: their effectiveness depends on both period band and local seafloor conditions. Higher-mode Rayleigh waves in the 3–10 s band are best recovered in deep water with thin sediments, while the 15–30 s band shows the most improvement in shallow water or in cases with strong tilt noise. These findings provide practical guidance for optimizing instrument selection and site planning for future OBS deployments.


For subduction-zone investigations, where offshore structure, sedimentary architecture, and plate-interface properties are key targets, these results will help researchers design deployments that maximize the quality of ambient-noise-derived constraints. The study also offers a framework for novel investigations of previous deployments, or for developing next-generation seafloor instrumentation.


Helen A. Janiszewski, Joshua B. Russell; Ambient Noise Analyses at Broadband Ocean‐Bottom Seismometers: Data Quality and Transfer Function Corrections. Seismological Research Letters 2025; doi: https://doi.org/10.1785/0220250106


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Scatter plot showing improvements in signal to noise ratio (SNR) of station-pair ambient noise cross correlation functions as a function of water depth with filters of 3-10 s and 15-30 s applied. At 3-10 s, where changes are primarily driven by reduction of Scholte wave signals and amplification of first-overtone Rayleigh waves, the most improvement is observed in deep waters for station pairs deployed at similar water depths. In contrast, improvements at 15-30 s are strongest at shallower water stations, as removal compliance noise from infragravity waves is the primary source of improvement.
Scatter plot showing improvements in signal to noise ratio (SNR) of station-pair ambient noise cross correlation functions as a function of water depth with filters of 3-10 s and 15-30 s applied. At 3-10 s, where changes are primarily driven by reduction of Scholte wave signals and amplification of first-overtone Rayleigh waves, the most improvement is observed in deep waters for station pairs deployed at similar water depths. In contrast, improvements at 15-30 s are strongest at shallower water stations, as removal compliance noise from infragravity waves is the primary source of improvement.


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