This issue's bannergram:

The last nuclear weapon test was conducted by China on 29 July 1996. The bannergram illustrates the explosion recorded at the closest IRIS GSN station in Ala-Archa (AAK), Kyrgyzstan, part of the International Monitoring System for the Comprehensive Test Ban Treaty. The magnitude of the event was mb = 5.2, corresponding to a yield of approximately 10 kilotons. The strong Lg arrival illustrates the value of regional recording for nuclear monitoring. Discriminants based on P to Lg ratios are effective for identifying Chinese tests at AAK. (see "The Beginning and the End" )

Table of Contents


CTBT... At last!

The Beginning and the End

Comparative Seismic Detection and Location Capabilities of IRIS and GSETT-3 Stations Within Central Asia

IRIS Concludes Nuclear Test Study for US Congress

The Last Nuclear Weapons Test?A Brief Review of the Chinese Nuclear Weapons Program

The Seismic Monitor

IRIS Assists Senate in Investigation of International Terrorist Group

GSN in Geneva

Comments to the Seismological Community

The Political Sensitivity of Earthquake Locations


Congressional Science and Engineering Fellowships

PASSCAL Education Initiatives

GSN Update


New Members

Ninth Annual IRIS Workshop

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