Update as of 05.10.2020
(Possibly) good news, everyone! The slow-slip interval pattern we witnessed between July of 2018 and February 2020 has finally changed. We have now gone a full three months without a slow-slip event (SSE) in the northern region of the CSZ. As shown in the graph, this means we are finally on an upward trend! See that last little plot point below? It is larger than the previous two intervals. More, there is not any current activity in the north indicative of an SSE. Perhaps the area will reset back to the average 14-month cycle… who knows.
What does this mean? I honestly have no idea. In respect to the research, it means that the CSZ can exhibit a continued shortening of intervals over several cycles, then reverse course WITHOUT a significant event occurring in between. There are some who argue this may be a small jump up before the trend goes back to shrinking (though again, I’m not sure how much farther it can shrink! The 2-month interval was already minimal).
This change in pattern remains exciting either way. To our knowledge, a pattern like we saw over the past two years, has never been observed without preceding a major event. Of course, these SSE’s have only been observed for a few decades. These major events are infrequent given those terms, so the number of observations have been few. Still, this new change shows us (and I assume other subduction zone regions around the world) that this behavior alone is not necessarily a precursor to a major event. That’s pretty cool!
This page began in January of 2020. If you have not been following along and would like more info, please continue to page 2 for explanations, research, and of course, scientific resources (peer-reviewed) previously posted.