Stories in Stone: How Geology Influenced Connecticut History and Culture

1. In the Beginning: Continental Fusion and Breakup

In the Beginning Continental Fusion and Breakup No one can understand Connecticut Who leaves the rocks out of his reckoning, Three hundred years, now, we have worked among them, And they have worked on us to more effect— —Odell Shepard, 1939 Rocks were and continue to be essential to life on Earth. When molten rock escapes from fissures and volcanoes, it carries oxygen and hydrogen, which combine as water vapor. These steamy clouds condensed and filled lakes and oceans over billions of years, painting the planet blue. Once at the surface, the igneous rocks, their volcanic offspring (the volcanic rocks that form when the magma reaches the surface), and their metamorphosed neighbors (older rocks around the throats of the volcano that are heated) disintegrate. The elements inside the rocks’ minerals escape their crystal prisons to become part of the soils, providing essential nutrients for plant life and in turn supporting the animal kingdom. Writers once in a while recognize the virtues of rocks. In Hermann Hesse’s famous novel, the title character, Siddhartha, says, “This is a stone, and within a certain length of time it will perhaps be soil and from the soil it will become a plant, animal or man.” Annie Dillard writes, “Rocks shape life, and then life shapes life . . . life and the rocks, like spirit and matter, are a fringed matrix.” However, most of us continue to view rocks as a boring nuisance. Farmers curse the rocks in c 1 their fields; highway builders blast them out of their chosen paths. Few people realize that without rocks and the materials derived from them, modern industry itself would come to an abrupt halt. Just about everything we use comes directly or indirectly from under the ground. Whereas cave dwellers needed just a few pounds of stone to fashion their spear points and arrowheads, contemporary Americans “consume ,” on average, more than twenty thousand pounds of stone, sand, and gravel per person annually and more than one thousand pounds of iron and steel. Rocks are literally the “bedrock” of our civilized world. As twentieth-century historian Will Durant points out, “Civilization exists by geological consent.” When compared to the topography of northeastern states such as New York or New Hampshire, Connecticut’s monotonous hills appear uninspiring (plate 2, top). Connecticut lacks the Finger Lakes, the Adirondacks , or the White Mountains. Because topography can reflect underlying geology, we might expect equally little diversity in the state’s rock types. The opposite is true, however: more rock types of different composition, texture, and origin are exposed in relatively small Connecticut than in most other states in the nation. Outcrops of bedrock commonly appear on ridge crests, in stream valleys, and along highways as reddish or grayish masses, implying a boring uniformity. On closer examination, though, they reveal almost painterly qualities —the boldly spattered stripes of Pollock, the smooth curves of Rubens . The stripes represent sediment layers deposited many millions of years ago in the shallow waters of bygone tropical seas; the curves are reminders of the crushing collisions of huge continental plates, which heaved and folded those sediments into today’s mountain ranges. Geologic Time Some drill and bore The solid earth and from the strata there Exact a register by which we learn That he who made it and revealed its date To Moses, was mistaken in its age. —William Cowper (1731–1800) In the Beginning 9 For many centuries, enduring religious beliefs guided ideas about the age and origin of the rock formations at the Earth’s surface. According to the Book of Genesis, God “constructed” Earth and everything on it in six days, and then rested on the seventh. Theophilus of Antioch was probably the first to use Genesis to try to estimate the age of the Earth; working around the year 180 ce, he concluded that creation began in 5515 bce. In the seventeenth century James Ussher, an Irish bishop, used an elaborate genealogical study of individuals mentioned in the Bible to conclude that the Earth was instead created in the year 4004 bce, and one of Ussher’s followers, John Lightfoot, went so far as to propose the exact date and time: October 23, at 9:00 a.m.! In Ussher’s scheme, Adam and Eve had a little over two weeks to enjoy Paradise before their expulsion on Monday, November 10. On May 5, 2348 bce, the ark ran aground on Mount...