Catalog of non-seismic short duration events offshore cascadia

Ocean-bottom seismometers (OBS) often record non-earthquake signals termed short-duration events (SDEs) that are typically recorded on one station with durations of ~1 s and frequencies between 4-30 Hz. Their origin has been attributed to animals bumping the sensor and a variety of physical mechanisms, including the passage of methane bubbles through sediments and across the seafloor.  We analyzed records from a subset of OBSs deployed on the Cascadia margin and Juan de Fuca plate as part of the Cascadia Initiative experiment and cabled OBSs from the Ocean Observatories Initiative Regional Cabled Array for the occurrence and characteristics of SDEs.  SDEs are observed on all OBSs at rates that vary by over two orders of magnitude.  This data set comprises a catalog of short duration from the OBS analyzed along with the Python code used to analyse the data, a list of stations and the time intervals analyzed, and ocean tide height predictions at each site.

Methods
The data set was collected with ocean bottom seismometers deployed as part of the Cascadia Initiative Experiment (Toomey et al., 2014)and as part of the Ocean Observatories Initiative Regional Cabled Array (Smith et al.).  Short duration events (SDEs) were detected by first filtering the seismic records with a 5-12 Hz bandpass filter and then using a recursive short term/long term RMS amplitude detector with a short- and long-term durations of 0.25 s and 30 s, respectively, and a trigger ratio of 4 (Withers et al., 1998).  Various parameters were then determined for each short duration event (SDE) as described in the README file accompanying this data set

Smith, L. M., Barth, J. A., Kelley, D. S., Plueddemann, A., Rodero, I., Ulses, G. A., ... & Weller, R. (2018). The ocean observatories initiative. Oceanography, 31(1), 16-35.

Toomey, D. R., Allen, R. M., Barclay, A. H., Bell, S. W., Bromirski, P. D., Carlson, R. L., ... & Wilcock, W. S. (2014). The Cascadia Initiative: A sea change in seismological studies of subduction zones. Oceanography, 27(2), 138-150.

Withers, M., Aster, R., Young, C., Beiriger, J., Harris, M., Moore, S., & Trujillo, J. (1998). A comparison of select trigger algorithms for automated global seismic phase and event detection. Bulletin of the Seismological Society of America, 88(1), 95-106.