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Passive seismic depth to bedrock data collected along streams of the Farmington River watershed, CT, USA

January 5, 2023

Using the horizontal-to-vertical spectral-ratio (HVSR) method, we infer regolith thickness (i.e., depth to bedrock) throughout the Farmington River Watershed, CT, USA. Between Nov. 2019 and Nov. 2020, MOHO Tromino Model TEP-3C (MOHO, S.R.L.) three-component seismometers collected passive seismic recordings along the Farmington River and the upstream West Branch of Salmon Brook. From these recordings, we derived resonance frequencies using the GRILLA software (MOHO, S.R.L.), and then inferred potential regolith thicknesses based on likely shear wave velocities, Vs, intrinsic to the underlying sediment. Three potential shear wave velocities (Vs = 300m/s, 337m/s, 362 m/s) were considered for Farmington River watershed sediments, providing a range of potential depth estimates along the Farmington. This release contains raw passive seismic recording data, processed resonance frequency data, and the resulting inferred depth estimates displayed in both tabular and vector form. This dataset currently contains 3 zipped files: 1) ‘’ is a zipped directory containing .asc text files of processed passive seismic data, individual processed reports, tabulated results, and an associated summary text file, 'readme_Processed.txt'; 2) '' contains .saf text files of passive seismic recordings and an associated 'readme_Raw.txt;' and 3) ‘'’ contains ESRI shapefile of HVSR point locations with attribute data & a map image offering a visualization of the depth results (where, Vs = 300m/s). Additionally, the main folder contains LegacyN_HVSR_readme.txt which describes these sub-directories in further detail.

Citation Information

Publication Year 2023
Title Passive seismic depth to bedrock data collected along streams of the Farmington River watershed, CT, USA
DOI 10.5066/P9FTZ0DK
Authors Kevin E Jackson, Adam B Haynes, Martin Briggs
Product Type Data Release
Record Source USGS Digital Object Identifier Catalog
USGS Organization Observing Systems Division

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