Why Bigger Quake Sows Less Damage Scientists Say Recent Temblors Are Unrelated; Underwater Topography May Explain Where Tsunami Wreaked Havoc By GAUTAM NAIK Three massive earthquakes have struck in less than two months, raising the questions: Are they related, and are we living in a time of more and bigger temblors? The Chile earthquake, 8.8 on the Richter scale, was by far the largest. But a little noticed 7.0 quake struck near Japan's Ryukyu islands just a few hours earlier, triggering its own tsunami warnings. The Jan. 12 temblor in Haiti was also 7.0, about 500 times less powerful than the Chile quake, though it appears to have killed many more people. That prompts yet another question: Why did a much larger quake cause much less destruction? Scientists say the three recent earthquakes probably aren't related, mainly because they occurred at such great distances from one another. To be sure, the back-to-back quakes in Japan and Chile both occurred along the no...