Continuous Tremor Activity With Stable Polarization Direction Following the 2014 Large Slow Slip Event in the Hikurangi Subduction Margin Offshore New Zealand

Many types of slow earthquakes have been discovered at subduction zones around the world. However, physical process these is not well understood. To monitor offshore earthquakes, a marine seismic and geodetic experiment was conducted Hikurangi margin from May 2014 to June 2015. During this experiment, large slip event (Mw 6.8) occurred directly beneath ocean bottom seismometer (OBS) network. In study, S-wave splitting polarization analysis methods, which previously used on onshore data investigate tremor anisotropy, are applied continuous OBS waveform identify tremors that too small detect by envelope cross correlation method. Continuous activity with stable directions detected end continued for about 2 weeks. The generated southwest bend in contours landward edge subducted seamount. Our findings corroborate previous interpretation, based burst-type repeating intermittent tremor, localized seamount triggered fluid migration following plate boundary indicate continuously rather than as isolated sporadic individual events.