Iceberg - Clive Cussler

The towering iceberg drifting in the North Atlantic was a floating tomb. Embedded in the great gleaming mass was a ship—sealed in so solidly that not even its mast protruded.

Here was a sea mystery to rank with the Bermuda Triangle and the Marie Celeste. But for Major Dirk Pitt, top trouble-shooter for the National Underwater and Marine Agency, it was also the first link in a fantastic chain of events that would lead him too close too often to violent death. And to the discovery of the most sinister and bizarre conspiracy of the century… Iceberg.