This project supports the deployment a dense array of seismic arrays around the Cook Strait in New Zealand to record deep tectonic tremor and aftershocks following the M7.8 Kaikoura earthquake. This was the second largest seismic event since the European settlement in New Zealand, and it triggered deep and shallow slow-slip events along the Hikurangi subduction zone. The ongoing slow-slip events have apparently increased the probability of an M~8 megathrust earthquake in this region. Hence, this network can provide useful information on how slow-slip and tremor evolves on the megathrust following a large earthquake. This project involves international collaborations among United States, New Zealand and China, and will support a junior faculty member at UC Riverside.
Four mini-arrays (each has 12 5-s flex-nodes) together with 17 short-period and broadband seismometers, will be deployed around the Cook Strait for up to one year. This hybrid network is strategically planned to complement and take advantage of the existing and planned deployment in the area to be able to have high-resolution locations of seismic events in the region. Seismic data collected during this experiment will be made available to IRIS DMC as soon as the experiment is finished. The collected seismic data can be used to understand the relationship among the M7.8 Kaikoura mainshock, ongoing afterslip, triggered slow-slip events and the accompanying tremor activities, and quantify the physical mechanisms for tremor and microseismicity.
