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The following info comes from an AP article dated yesterday: A team of geologists and graduate students are conducting a study in the Adirondack Mountains in upstate New York which they hope will show the existence of a 'hot spot' in the Earth's mantle deep below the area. Mantle hot spots generate pockets of geothermal and volcanic activity in the crust above them. The Hawaiian Islands were formed from a hot spot below the Pacific crustal plate, and the northwestward arc of the island chain shows how the plate has moved across the hot spot over the last few million years. Another hot spot is thought to be responsible for the geothermal activity in Yellowstone National Park. Now geologists Steve Roecker and Steve Tice, of the Rensselaer Polytechnic Institute in Troy, NY, are investigating the possibility of a hot spot beneath the Adirondacks. According to Yngvar Isachsen, chief geologist at the New York State Geological Survey, the Adirondacks are a circular uplift, unlike the Appalachians and most other mountain ranges which are the results of folding and faulting. Isachsen believes the circular uplift is the result of a thermal plume from the Earth's mantle. He also thinks the mountains are still growing, possibly by as much as a millimeter a year. The survey currently underway requires that Roecker, Tice, and their students locate a number of markers left by geologist Verplanck Colven in his detailed survey of the area 130 years ago. They will then use satellite transmitters and the Global Positioning System to obtain extremely accurate data for the current positions of those markers. The GPS position data will be compared to Colven's data and also to data from more recent surveys. If the markers are found to be moving apart, that will be excellent evidence for a "doming" type uplift and hence for a hot spot below the Adirondacks. "Even though the old surveys were far less accurate than what we'll get with GPS, if the Adirondacks are moving up at a high rate, there should be enough displacement over the 30, 60 or, in Colvin's case, 130 years, for us to see it," Roecker says. Jon W.