India has released an image of one of these shots showing a surface crater in a sand dune. The dune crater, judging by the sand bags in the image is quite small, perhaps 3.5-4 meters from rim to rim. The yield for producing this feature could be anything from a few hundred kg of explosive yield upwards, depending on the depth of burial and the mechanism by which the surface crater was formed.
In addition to this photographic evidence, BARC has published purported sample radiation measurements from all three sub-kiloton [Attarde et al 1999] test sites . Given the brevity of this article, and the lack of any substantive analysis, the apparent sole reason for this article's publication was to provide proof that they did actually occur. Accepting this evidence as genuine, at this writing no explanation of the anomaly of non-detection is at hand. BARC does not appear to have offered an explanation for this mystery. One possible resolution of this question is to postulate that Shakti IV-V were fired at the same time as the other Shakti shots. This contradicts all reports emanating from India however.
The consensus among outside seismic experts is that the yields of most Indian tests are overstated (particularly Pokhran-I or "Smiling Buddha" and Shakti-I), and that the very existence of Shakti IV-V is in question. Interestingly, the case with the Pakistani tests (conducted in a far different geological environment) is similar - claimed yields do not match the seismic evidence. No well-founded explanation is available for such a consistent pattern of deception by both India and Pakistan.
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