plumbing system that piped the lava from the Earth's interior to the surface, then they must have originally been below the flows. Hence, they now should lie west of the Metacomet Ridge - which they do.

The Changing Face

As the preceding pages show, the land has changed dramatically through geologic time. Connecticut's four terranes have shifted, crashed, and pulled apart like beat-up Cadillacs in a demolition derby. In the process, an ocean closed and a new one opened, continents collided and broke apart, mountains were built and eroded away. This section recaps this complex geologic novel of nature and puts its events in straight chronological order.

The workings of the continental collision were set into motion 500 million years ago, near the beginning of Paleozoic time. At that time, Connecticut probably looked a bit like the present southeastern United States and Caribbean Ocean. A carbonate bank, similar to Florida or the Bahamas, flanked the edge of Proto-North America. Across a wide stretch of water lay Avalonia, a series of large islands or minicontinents similar to Puerto Rico, Cuba, and the Virgin Islands. As this was before the evolution of land plants and animals, Proto-North America and Avalonia were rather desolate-looking places. No trees, no shrubs, even no grass - nothing to hold back the drifting sand and sloppy mud. Land at that time was probably a sort of wet Mars. As far as life was concerned, the oceans were where everything was happening. The warm water supported a diverse group of creatures, such as trilobites (large marine sowbugs), the coral like archeocyathids, jelly fish, primitive snails, and early members of the starfish and shrimp families.

As the Iapetos continued to close, a subduction zone formed just west of Avalonia and soon began sporting a line of volcanic islands. Connecticut was probably still 500 to 2000 miles wide at this time. Life was evolving in its slow Darwinian way, and the first few pioneering

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