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The rise (and rise) of the Adirondacks

One million years agobefore there was an Adirondack Park with seasonal tourist attractions, environmental regulations, beaver ponds, and imaginary Blue Linesthere was a vast untamed wilderness of mountain rock and ice. It is doubtful that there were many trees or even much wildlife in the arctic-like terrain. But go back 10-15 million years, or even more, and the Adirondack Mountains we know today may have been barely noticeable, at least according to a fascinating theory championed by a maverick New York geologist who died in 2001. At that remote moment in time, the geologist claimed, the climate was warmer and the Adirondacks were literally new-born mountainsthe result of a domical uplift that continues to the present day. During the Miocene Epoch, the theory states, deep below the future State of New York, a molten hot spotcaused by the radioactive decay of uranium and thoriumbegan heating subsurface rocks causing them to expand and rise through the rock layers above it. For more than 30 years, the late Dr. Yngvar Isachsen, a Cornell University trained geologist, challenged long-held beliefs about the age and origin of the Adirondacks. But some of Isachsens conclusions have been, in turn, challenged by new data collected by the New York State Geological Survey and other sources. Dr. William M. Kelly, chief geologist of New York State, said theres more research needed to fully understand the origin and age of the Adirondacks. According to Kelly, his late colleague, Dr. Isachsen, studied the upstate mountain range in depth and corrected many long held myths about the Empire States big peaks. However, hes not sure the mountains are rising as rapidly as Isachsen claimed. Instead, he blames instrument data and inaccurate, older data on any confusion. More recent rock-dating data suggests theres a longer, slower rise going onmaybe starting 130 million years ago, Kelly said. Yet the edges of the mountain dome appear younger. But even with that said, why are these mountains rising so far from a plate boundary? Maybe Yngvars hot-spot theory will prove to be as good an explanation as any other. Maybe theres a plume of magma stuck to the bottom of the continental plate? We just dont know. In the late 1990s, Kelly said, a research team from Rensselaer Polytechnic Institute conducted a global positioning system (GPS) study of the High Peaks region to see if the Adirondacks were rising rapidly. The team camped out and collected data for 72 hours. They discovered they couldnt get a reliable answerthey couldnt compare their data to existing data including pioneer Adirondacker Verplank Colvins survey data of the 1870s because of various errors. So the RPI field trip didnt amount to anything. Using the 1990s data, RPI researchers plan to recheck the GPS results in 10 years. Regardless, Dr. Kelly backed up some of his late colleagues claims The Adirondacks are not old by standards of deep geological time (however, they are composed of very ancient, metamorphosed sedimentary and igneous rocks). Dr. Isachsen believed the Adirondacks started forming 5-10 million years ago; Dr. Kelly believes they are olderup to 130 million years old. The Adirondacks appear to be growing, but probably not at a rate faster than the Alps as claimed during the 1990s (1 millimeter per year). The Adirondacks are not a product of Ice Age rebound. Kelly said many domical mountains are associated with hot spots. But in some cases, as seen on other planets, huge asteroid impacts can create dome mountains. In Africa several dome mountains are erupting lava. Isachsen believed lava might someday break through the rocks of the Adirondacks. It wont happenif it happens at allfor millions of years in the future, Kelly said. According to New York-based science writer Phil Brown, As the Adirondacks rose, they shed the upper crust and exposed ancient rock that normally exists about 20 miles underground. Thus, the mountains, though relatively young, are filled with clues to the early history of the Earth... Brown writes that the mountains are experiencing a growth spurt shooting up 30 times as fast as they are eroding. The summit rocks of the Adirondack High Peaks were formed 1.1 billion years ago. Called anorthosite, these rocks closely resemble rocks found in the Moons highlands; samples were brought back to Earth by NASA astronauts in the 1970s. Unlike lunar anorthosite, which is not metamorphosed, Adirondack anorthosite rock has been cooked in the subterranean deeps before being exposed in mountain peaks. According to Dr. Isachsen, ground-truth bolstered his hot-spot theory at the famous carbonated springs bubbling up around Saratoga Springs, N.Y. The Island Spouter (spring) in Saratoga Springs State Park blows ten feet into the air like a geyser, he once said. Driven by carbon dioxide pressure, it erupts like an improperly opened bottle of champagne. Although lacking the drama of a volcano, the spring marks a deep scar in the Earth where ancient rocks of the Canadian Shield continue to rise above the lowlands of the young Adirondacks. But Dr. Kelly doesnt agree that the springs around Saratoga Springs are connected to deeper things going on in the mantlethe pipes are too shallow. You know, I loved Yngvar like a brother, Kelly said, but I still cant agree with all of his scientific claims. But he posed some very intriguing questions. Despite all the new data, the Adirondacks remain a mystery waiting to be solved.

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