This was the map shown by the NBE eight hours after the Aug. 1 1999 M5.7 Scottys
Junction earthquake.
The NBE is now produced by a CUSP/ISAIAH automatic detection system running on
our VAX stations from high-gain vertical instruments only.
As a result of these stations being saturated by foreshocks and aftershocks, the NBE missed the
main shock. Detection of all other events was reliable.
The very widely scattered automatic locations are the result of poor station coverage for
the Scottys Junction area, and poor automatic arrival picks from clipped stations.
Archived maps demonstrate the NBE has responded to all felt events in our area within the past three years. It has always provided a location and an underestimated magnitude within 30 minutes of the event.
This is a GIF version of the map we currenlty produce in our own format. It is readily accessible to any web browser but not at all interactive. During an average week this map is downloaded several hundred times. After an early Nov. 1998 Lake Tahoe event the map was downloaded over 2900 times (total site hits that week exceeded 150,000).
This is the map shown by the JavaWorm interface 8 hours after the
Scottys Junction earthquake. Although it contains exactly the same
locations as the map above, the interactive listing and attractive
topographic image make it a popular vehicle for the NBE. During an average
week the Java interface is run several hundred times. After an early
Nov. 1998 Lake Tahoe event the map was downloaded over 2700 times.
This was the map shown by the NBE one day after the Aug. 1 1999 M5.7 Scottys
Junction earthquake.
Analyst locations have made geographic sense of the sequence.
The NBE never broadcast the main shock.
Above is an internal Antelope system display as seen 8 hours after the
Scottys Junction earthquake.
Since this Antelope orb used high-dynamic-range instruments near Yucca Mountain,
the locations are much improved over those of the CUSP/ISAIAH NBE at the same time,
though still tens of kilometers off in many cases.
The main shock is well-located.
This map represents the minimum degree of accuracy we want to acheive with our rapid earthquake notification systems. Such improvement will demand better station coverage with high-quality stations, new data-logging technology such as Antelope, or a vastly improved Earthworm, and adoption of a standard format for web maps of earthquakes.
This is the simple GIF map of the analyst-corrected "finger list" events in the
Scottys Junction sequence.
Due to aging VAX data-logger technology and lack of resources for staff support
and backup, this map did not appear until one week after the event.
During previous events an equivalent map usually appeared within a few days
of the event, as staff were able to analyze data.
This display has been about 20% more popular than either of the NBE
displays via GIF and Java formats.