Re #16
The crater could be shallow, but visible. At least wouldn't the height of (hill or mountain) change by a few meters.
By the way, are you sure that it was 6000 feet underground? That is 1,800 meters, which is really deep. The tunnel cannot be horizontal. The hill is merely 1,200 feet high.
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The crater could be shallow, but visible. At least wouldn't the height of (hill or mountain) change by a few meters.
By the way, are you sure that it was 6000 feet underground? That is 1,800 meters, which is really deep. The tunnel cannot be horizontal. The hill is merely 1,200 feet high."
Was the test done at the following mentioned location?
N Korea's bomb 'would kill 200,000'
The Telegraph By Sergey Soukhorukov in Pyongyang
"
The Russians believe the test, if it happens, is likely to be carried out in a horizontal tunnel more than a mile below ground at Kilju, in North Hamgyon province, in the north-east of the country where US military satellites have detected recent activity."
Some commenters have also mentioned gamma ray detection efforts. Even initial rays would not be detectable through that much earth. With enough horizontal airspace (to spread out the settling effect in a tunnel) and so much earth above the shot, I doubt that a surface crater would be visible.