...—a US contribution to the international PacificArray project. The “Young ORCA” array deployed on ∼40 Ma central Pacific seafloor had a ∼68% data recovery rate, whereas the “Old ORCA” array deployed on ∼120 Ma southwest Pacific seafloor had a ∼80% recovery rate. We detail here the seismic data quality...

...., 2019) has gained some momentum. The idea of deploying temporary large aperture arrays of broadband sensors (e.g. PacificArray, Kawakatsu et al., 2019) has largely replaced the concept of permanent isolated borehole very broadband stations and the Pacific basin is progressively being covered...

... supplemental content for results of tests at different water depths). This is similar to the average water depth of the Young Pacific ORCA experiment, in which the tool is applied in the Application to PacificArray Deployment section, allowing for easier comparison. Furthermore, the magnitude...

... ), including cabled observatories (e.g., Kawaguchi et al. , 2007 ; Barnes et al. , 2008 ; Kanazawa, 2013 ; Smith et al , 2018 ; S‐net, ALOHA) and recent efforts at floating arrays of hydrophones (e.g., Sukhovich et al. , 2015 ) and large aperture seafloor broadband seismic arrays (e.g., PacificArray...

... of the Pacific array initiative is available at http://eri-ndc.eri.u-tokyo.ac.jp/PacificArray/ . Seismograms and differential pressure gauges (DPG) data from the Oldest‐1 array were collected by the Seoul National University (SNU) and Earthquake Research Institute (ERI) during the cruise from 26 October to 9...

...://earthquake.usgs.gov/earthquakes/ ), Ocean Networks Canada: Neptune Array ( http://www.oceannetworks.ca/observatories ), Ocean Observatories Initiative ( https://ooi-website.whoi.edu/array/cabled-axial-seamount/ ), and Pacific Array ( http://eri-ndc.eri.u-tokyo.ac.jp/PacificArray/ ). All websites were last accessed...

... for studying these processes, and it has been the focus of a number of experiments exploiting recent advances in marine-seismic instrumentation, including those affiliated with the multinational grassroots collaboration PacificArray. We invite contributions from scientists using active- and passive-source...