Richter scale a poor measure of localized shaking

After an earthquake like the one that struck Cook Inlet on Sunday morning, everyone wants to know how big it was. Scientists use the Richter scale to describe the magnitude of an earthquake. But getting to that number is a complicated process. And it has some major limitations.
A USGS earthquake map shows lots of seismic activity around Anchor Point, including the 7.1M shaker felt from Fairbanks to Juneau (big yellow dot). Image: screen grab from USGS
Numbers like 6.4… 7.3… 6.8 &md