At first I'd like to show that a vertical time axis, Hour, in a heliplot can be displayed with slipping off for one hour, which sometimes happens when a heliplot screen is updated, and I have noticed it since the first series.
An example is the following figure.
So I showed the outbreak time for Jolt as follows, 14:10(15:10) at VNDA.
Judging from a pattern of these a series of Jolt, in Antarctica, Africa and South America, there seems to be something of a one-week cycle causing this in the Earth wobble now.
* GSN Heliplots: http://earthquake.usgs.gov/monitoring/operations/heliplots_gsn.php
[Heliplots of 3rd Series]