Station details:
================

Code: ERK
Latitude:  46.30560
Longitude: -122.34100
Elevation:  1270.0
Depth: 
Name: Elk Rock
Region: Washington,U.S.A.
Status: 

        
Arrival picks statistics
Travel Time Analysis
On the top graph every dot represents the median residual for one month of data. The green line is the overall median; the orange line shows the standard deviation (smad) based on the median absolute deviation (mad), whilst the red line shows twice the standard deviation (2 * smad).
The bottom graph shows the number of residuals for each month. The red columns show the number of residuals whose median (for that month) is outside two standard deviations from the overall median (2 * smad).
Red dots indicate a possible clock error.
 

Station comments:
=================

opened 198005
SEA code ELK

Data at the ISC for 33 years between 1987 and 2020.