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

Code: NA2
Latitude:  38.12789
Longitude:  -77.74011
Elevation:    99.0
Depth: 
Name: North Anna
Region: Virginia,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:
=================

197810-19930810
USTN before 198511-19930810

Data at the ISC for 16 years between 1979 and 1996.

Known station history:
======================

First and Last use refers to the time period in which the coordinates were used by the ISC.

Code   Station name/Region                                           Latitude  Longitude Elevation   Depth  First use   Last use
================================================================================================================================

NA2    North Anna                                                    38.12780  -77.74010                   25-08-1999 25-08-1999  
       Virginia