One question (or several related questions) I have regarding Collins' theory that the ship sunk whole and was separated by an underwater earthquake in '29:
How does that account for the debris placement, especially the coal, which is scattered yet spread in a uniformed pattern across the seabed? It's hard to believe that an earthquake would have caused the debris to land as it did on the ocean floor.
Also, it would seem that an underwater earthquake powerful enough to have torn the ship in two and thrown the stern some hundred's of feet away (and flipped it around so that the stern itself was pointing in the same direction as the bow) would have undoubtedly done worse damage to the ship - internally and externally.
Finally, such a premise would have to consider, and acknowledge, the many eyewitness accounts which claimed that the ship broke apart at the surface. If the ship hadn't broken at the surface, so many people, unrelated and placed at different locations around the sinking liner, wouldn't have seen the break.
No disrespect to Capt. Collins, but his theories (sinking whole and the earthquake involvement) are weak and don't hold water (pun intended). With an underwater earthquake powerful enough to tear the Titanic in two and throw the stern a considerable distance away, such an earthquake, as Michael suggested, would have created a fault line, or an opening that would have swallowed and, perhaps, destroyed the wreck entirely or almost entirely. Capt. Collins is an experienced seaman, but how experience and knowledgeable is he regarding earthquakes and tatonic places? That's a whole other ball-or-wax.
To comment on the initial question of fault lines, I would say no, for the simple reason that had there been fault lines near the Titanic, the earthquake of '29 (and other subsequent underwater folly) would have destroyed the wreck. It's an interesting consideration, though.
Just my thoughts...