Lockloss @ 10:05 UTC from what seems to be a nearby and sudden seismic event. The motion appeared quickly in both 0.03-0.1 and 0.1-0.3 Hz frequency bands and Picket Fence did show small motion on all sensors a minute or so after the lockloss. This event does not correspond to any earthquake reported by USGS.
Seismic configuration did not switch to EARTHQUAKE until the second wave hit (around -5m on attached ndscope). Waited in DOWN for about 10 minutes for ground motion to calm down, now relocking (and anticipating an incoming 6.2 from Japan).
The timing of this event in relation to the 6.2 magnitude quake from Japan is noteworthy, but this lockloss occurred before seismon or the USGS site reported the incoming Japan quake, which is why I hesitate to say whether the two events are the same or not (but still entirely possible).