Ocean Networks Canada (ONC; http://www.oceannetworks.ca/) operates the multidisciplinary NEPTUNE and VENUS cabled ocean observatories off the west coast of Canada and an increasing number of miniature ocean observatories, such as in the Canadian Arctic. All data collected by these observatories are permanently archived and publicly available through ONC’s Oceans 2.0 data portal. Much of the data are related to marine geohazards, such as earthquakes, submarine landslides and tsunamis and are delivered in real-time, including to early warning centers. The NEPTUNE cabled observatory consists of an approximately 800-km long cable loop deployed off the west coast of Vancouver Island that covers the coastal zone, the northern part of the Cascadia subduction zone, Cascadia Basin and the Endeavour Segment of the Juan de Fuca Ridge. The observatory includes several high-precision bottom pressure recorders (BPRs) at each of its five active nodes. On September 30, 2009, just days after the first instruments were installed, six BPRs on the array recorded tsunami waves of 2.5 to 6 cm amplitude originating with the Mw 8.1 Samoa earthquake. The Samoan tsunami was followed by several other events recorded by the network, including those of the 2010 Chilean tsunami, the 2011 Tōhoku-Oki tsunami, and the 2012 Haida Gwaii tsunami. We will review the decade of open-access bottom pressure recorder data, instrument development, and research findings across many disciplines and give an outlook for future developments.

We use ocean bottom seismometer data from the Endeavour segment of the Juan de Fuca ridge to construct a long-term earthquake catalog for an intermediate-rate spreading ridge. We present > 50,000 new earthquake locations for 2016-2021 from the Ocean Networks Canada NEPTUNE cabled observatory and relocate earthquakes from two autonomous networks in 1995 and 2003-2006. The catalog comprises > 85,000 earthquakes located using three-dimensional segment-scale P- and S-wave velocity models from a prior tomography experiment. Despite the small footprints of networks near the segment center, locations show good agreement with geologic features at segment ends. The improved locations show that the northern Endeavour segment ruptured southwards from 48.3°N to 48.05°N during two diking events in early 2005, possibly accompanied by diking on the West Valley propagator. Persistent off-axis seismicity near the segment center appears to be related to the West Valley and Cobb propagating rifts which we infer extend ~10 km closer to the Endeavour segment center than is apparent in bathymetry. We suggest that the proximity of the propagators to the Endeavour vent fields contributes to the localization, vigor and longevity of the fields by focusing permeability through ongoing fracturing and by limiting extrusive magmatism through degassing of the axial magma lens. Increasing rates of seismicity beneath the vent fields beginning in late 2018 and a deepening of earthquakes in 2020 indicate that the central portion of the segment may be entering the later stages of the eruptive cycle.