The Russian "FOAB".
Here's the father of all bombs: Russia's answer to the MOAB
"The so-called father of all bombs is thought to be about four times as big as the MOAB. It's a thermobaric bomb with a destruction radius of nearly 1,000 feet and a blast yield of nearly 44 tons of TNT. "
https://en.wikipedia.org/wiki/Earthquake_bomb
Wallis’ first concept was for a ten-ton bomb that would explode some 130 feet (40 m) underground. To achieve this, the bomb would have had to be dropped from 40,000 feet (12 km). The RAF had no aircraft at the time capable of carrying a ten-ton bomb load aloft, let alone lifting it to such a height. Wallis designed a six-engine aeroplane for the task, called the “Victory Bomber”, but he was not taken seriously by the military hierarchy of the day.
Wallis then took a different line in developing a means to destroy Germany’s industrial structure with attacks on its supply of hydroelectric power. After he had developed the bouncing bomb and shown its possibilities, however, RAF Bomber Command were prepared to listen to his other ideas, even though they often thought them strange. The officer classes of the RAF at that time were often trained not in science or engineering, but in the classics, Roman and Greek history and language.[citation needed] They provided enough support to let him continue his research.
Later in the war, Barnes Wallis made bombs based on the “earthquake bomb concept”, such as the 6-ton Tallboy and then the 10-ton Grand Slam, although these were never dropped from more than about 25,000 feet (7.6 km). Even from this relatively low altitude, the earthquake bomb had the ability to disrupt German industry while causing minimum civilian casualties. It was used to disable the V2 factory, bury the V3 guns, sink the battleship Tirpitz and damage the U-boats’ protective pens at St. Nazaire, as well as to attack many other targets which had been impossible to damage before. One of the most spectacular attacks was shortly after D-Day, when the Tallboy was used to prevent German tank reinforcements from moving by train. Rather than blow up the tracks — which would have been repaired in a day or so — the bombs were targeted on a tunnel near Saumur which carried the line under a mountain. Twenty-five Lancasters dropped the first Tallboys on the mountain, penetrating straight through the rock, and one of them exploded in the tunnel below. As a result, the entire rail line remained unusable until the end of the war.
After World War II, the United States developed the 43,000-pound (20,000 kg) T12 demolition bomb that was designed to create an earthquake effect.
” thermobaric bomb”
Which reminds me....
Thermobaric Bomb Destroys Hobbit Hole
http://www.freerepublic.com/focus/f-news/639647/posts