Abstract On November 15, 2017, an event related to the disappearance of Argentine military submarine ARA San Juan was detected by two hydrophone triplet stations IMS network, established enforce nuclear test ban treaty (CTBT). From direct hydroacoustic arrivals recorded at 6000 and 8000 km from localized wreckage, calculated location based on data only is poorly constrained, associated uncertai...

In CTBT applications many events of interest are only detected at regional distances. Providing more accurate prediction of P-wave propagation at regional distances is therefore of particular importance in seismic event location. At such distances (2 -14 ) the phase Pn is the seismic phase that is most frequently reported and which thus controls the location accuracy. We are working on reducing...

In recent years, numerous regional seismic event discrimination studies have shown that the high-frequency (usually greater than 3–4 Hz), P/S spectral amplitude ratios of regional P (Pg or Pn) and S (Sg, Sn or Lg) waves observed at distance range from few kilometers up to about 2,000 kilometers, provide an efficient method to classify regional earthquakes, quarry blasts and underground nuclear ...

Measuring radioactive xenon isotopes in the atmosphere is an important technique used for monitoring within the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Several process steps are needed to capture and prepare a xenon sample suitable for transfer to a nuclear detector. These processes include air drying, xenon collection, concentration, and purification. The ideal xenon sampling system woul...

The seismic arrays of the International Monitoring System (IMS) for the Comprehensive Nuclear-Test-Ban Treaty (CTBT) are highly diverse in size and configuration, with apertures ranging from under 1 km to over 60 km. Large and medium aperture arrays with large inter-site spacings complicate the detection and estimation of high-frequency phases lacking coherence between sensors. Pipeline detecti...

Within the scope of the Comprehensive Nuclear-Test-Ban Treaty (CTBT), four methods are used to verify the treaty. One of these methods is based on the detection of infrasound waves generated by a nuclear explosion. Seismological, hydroacoustical and radionuclide measurements are also applied. The International Monitoring System (IMS) will consist of 60 infrasound stations of which 35 stations a...

The U.S. Department of Energy’s (DOE) Comprehensive Nuclear Test-Ban-Treaty (CTBT) Knowledge Base (KB) contains detailed regional data, from which corrections to seismic, hydroacoustic, and infrasonic signals will be generated. As the KB is populated with information and data sets detailing regional geological and geophysical structures and reference event data, questions of “How good is the in...

For purposes of monitoring compliance with the Comprehensive Nuclear Test-Ban Treaty, it is desirable to be able to locate seismic events routinely to within an uncertainty not greater than 1000 square km. From more than five years of experience with publication of the Reviewed Event Bulletin (REB) by the Prototype International Data Centre (PIDC), resulting in estimated locations for more than...