Ocean‐Bottom Seismograph Performance during the Cascadia Initiative

Abstract

Online Material: Figures showing channel uptime and quality. The Cascadia Initiative (CI) is a community designed and implemented onshore/offshore seismic and geodetic network deployed along the Cascadia subduction zone from northern California to Vancouver Island (Toomey et al. , 2014). The goal of the initiative was to investigate a variety of questions related to megathrust earthquakes (e.g., Atwater et al. , 1995), episodic tremor and slip (e.g., Rogers and Dragert, 2003), volcanic arc structure (e.g., Parsons et al. , 1998), and the overarching interactions between the Juan de Fuca and Gorda plates. The CI operated from 2011 to 2015 and was funded by the National Science Foundation as part of the American Recovery and Reinvestment Act. The funding supported the construction of an amphibious array (AA), which comprised 60 three‐component broadband ocean‐bottom seismographs (OBSs), the deployment and operation of land‐based seismographs as part of the USArray Transportable Array, and the upgrade of Plate Boundary Observatory Global Positioning System (GPS) stations to high‐rate real‐time data. The Woods Hole Oceanographic Institution (WHOI), Scripps Institution of Oceanography (SIO), and the Lamont–Doherty Earth Observatory (LDEO) constructed the OBSs as part of the Ocean Bottom Seismograph Instrument Pool (OBSIP). The Cascadia Initiative Expedition Team (CIET; cascadia.uoregon.edu) deployed the OBSs over four consecutive summers from 2011 to 2014, and each deployment lasted approximately one year. The CIET team deployed almost four times more instrumentation than the average broadband OBSIP experiment, and data recovered from the CI are openly available to the entire scientific community immediately after instrument recovery. In an effort to make the CI data widely available, the Incorporated Research Institutions for Seismology (IRIS) OBSIP Management Office (OMO) performs data quality assessments as part of archiving the data at the IRIS Data Management Center (DMC). In this study, we focus on OBS station performance, data return, and horizontal …