This is a continuation of fairly normal activity along that plate boundary of the coast of Oregon. I have watched this whole area for a long time just for grins.
I have another map that may put some of it into perspective.
That is a mouthful if you had to say it but it works out to be the locations of every event with a magnitude greater than 4.5 since Jan. 1, 2018 in the map area defined by the coordinates in the link (basically bounded on the east by the Nevada border, on the south by the California/Mexico border, on the north by the northernmost quake in Idaho, and on the west by the plate boundary where we see the new activity.
Notice all the events along the California/Nevada border. Most of those are related to the July 2019 Ridgecrest earthquake which was a magnitude 7.1 event preceded about 34 hours earlier by a magnitude 6.4. Since that event, the faulted zone from Ridgecrest toward Mammoth Lakes and on to Carson City has seen increased activity that propagates from south to north and that has reactivated the east-west fault that runs east of Mono Lake into Nevada. Over time, probably the next few years, you will likely see similar quakes between Carson City and Medford, Oregon along that zone. That appears to be the eastern end of the plunging plate where we see the current quake swarm if you trace it out. (The edge may be near Yreka/McDoel CA area in the Cedar Mtn Fault System where the main faulting along the eastern Sierra/Cascades takes a more northerly turn.
Remember that the red squiggles are mapped faults and that they are actually continuous in the subsurface along zones of faulting that follows the general squiggle trend.
The latest activity on the transform fault offshore just continues that older trend (grey dots are events that have happened since Jan 1, 2018 and that are more than a month old) out to the western edge of that plate.
Interesting stuff. I'm not a seismologist, just a geophysicist. This stuff interests me as I like to look for patterns in life. Don't use any of this in any official capacity. Follow the science and take everything in this post as a simple description of one person's observations of events and data in one geographic area that probably could be interpreted in multiple ways, even by the same person. As such this is meant to entertain, not to inform.
I have another map that may put some of it into perspective.
https://earthquake.usgs.gov/earthquakes/map/?extent=30.82678...
That is a mouthful if you had to say it but it works out to be the locations of every event with a magnitude greater than 4.5 since Jan. 1, 2018 in the map area defined by the coordinates in the link (basically bounded on the east by the Nevada border, on the south by the California/Mexico border, on the north by the northernmost quake in Idaho, and on the west by the plate boundary where we see the new activity.
Notice all the events along the California/Nevada border. Most of those are related to the July 2019 Ridgecrest earthquake which was a magnitude 7.1 event preceded about 34 hours earlier by a magnitude 6.4. Since that event, the faulted zone from Ridgecrest toward Mammoth Lakes and on to Carson City has seen increased activity that propagates from south to north and that has reactivated the east-west fault that runs east of Mono Lake into Nevada. Over time, probably the next few years, you will likely see similar quakes between Carson City and Medford, Oregon along that zone. That appears to be the eastern end of the plunging plate where we see the current quake swarm if you trace it out. (The edge may be near Yreka/McDoel CA area in the Cedar Mtn Fault System where the main faulting along the eastern Sierra/Cascades takes a more northerly turn.
Remember that the red squiggles are mapped faults and that they are actually continuous in the subsurface along zones of faulting that follows the general squiggle trend.
The latest activity on the transform fault offshore just continues that older trend (grey dots are events that have happened since Jan 1, 2018 and that are more than a month old) out to the western edge of that plate.
Interesting stuff. I'm not a seismologist, just a geophysicist. This stuff interests me as I like to look for patterns in life. Don't use any of this in any official capacity. Follow the science and take everything in this post as a simple description of one person's observations of events and data in one geographic area that probably could be interpreted in multiple ways, even by the same person. As such this is meant to entertain, not to inform.