The Adirondack Impact

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     The Adirondack Mountains are located in the northern part of New York State, as marked by the yellow bullseye.

     These mountains were formed by a massive impact that transformed a large part of North America.

      This mountainous area ranges in elevation from under 1,200 feet (366 m) to over 5,000 feet (1,524 m) in elevation. The higher peaks are in the Northeastern section, this being the initial indication that the object came in from the Southwest. It appears to have been a roughly spherical object.  As the area is not associated with volcanism or major fault lines, this indicates that this was a 'soft hit', meaning that the object was relatively slow moving and loosely packed. This is opposed to a hard rock asteroid at high velocities which would fracture the crust of the Earth, or punch a hole in it leading to volcanism.
     The area is about 160 km (100 miles) wide. Using rough calculations, the average elevation increase (5000 ft - 1200 ft  = 3800 feet), less the base land elevation +/- 700 feet  = 3100 feet or 945 meters of thickness added to the Earth. This thickness, in relation to the width, indicates that the object flattened upon impact. If the object pushed an equal amount of material below the surface as it left above the surface when it hit, then the compressed mass has a thickness of 6200 feet (1890 meters). If we consider that this object was roughly spherical before impact, then the density before impact would have been (1890 meters / 160,000 meters) = 0.0118 times what it is now.  These indications suggest that this was a large dust ball, a comet that had traveled the universe for millions or billions of years collecting matter as it passed, bit by bit.  The gravity of an object 160 km (100 miles) in diameter, would be infinitesimal in comparison to the Earth, this accounting for the very low density.
     Although this comet was spread out over enough area that it did not punch a hole in the crust of the Earth, this is not to discount its significance. This mass of earth 160 km in diameter and 1890 meters thick was enough to form seismic shock waves that rippled across much of North America, reforming the land as it passed, as the following images will show.

    At 80 km radius, this circle shows the primary impact area. The higher peaks are to the Northeast of the center of impact, indicating that the comet came in from the Southwest.

      At 100 km radius the Mohawk River Valley follows the circle to the southwest past Utica and Little Falls, New York.

      At 130 km from the center of impact, the St. Lawrence River was nudged to form this arc to the Northwest.

      At 205 km to the Northwest, the shock wave from the impact defined the course of the Ottawa River, and part of the boundary between Ontario and Quebec Provinces, Canada. Political bounraries are often drawn to follow the form of the land. Rivers are an easy dividing line and are often used for this purpose.

      At 360 km, the shock waves defined the southern coast of Long Island.

      At 755 km the shock wave defined the James River, which flows to the south of Newport News, Virginia.

      At 1120 km to the North, the shock wave provided the valley for La Grande Riviere Reservior in Quebec.

      At 1460 km to the West, the St. Croix River demarcates the boundary between Minnesota and Wisconsin, until it meets with with the Mississippi River, near Minneapolis.

      At 1460 km to the Southwest, the Mississippi River forms the boundary between Missouri, and Illinois.

      At 1780 km to the West, the Missouri River forms the border between Iowa and Nebraska, and part of Kansas and Missouri.

      At 2110 km to the Northwest in Manitoba, Canada, the Churchill River parallels the shock wave circle before it empties into the Hudson Bay.

      At 2110 km to the Southwest, the Red River (which forms the Texas, Oklahoma border) aligns to the seismic circle in Lousiana as it joins with the Mississippi River, which then flows to the Gulf of Mexico.

      The full extent of the seismic shock wave circles in the above images is pictured here. To see this image full sized, CLICK HERE or on the image above. As stated earlier, deformations of the land not be visible on the ground the entire distance around the circle. This is because the shock wave, as powerful as it is, can move some ground easliy, and other ground that may be more dense, not so easily. Also other impacts that came later will obscure the circles.
      What is shown here is only the major land deformations caused by this impact. A closer examination will find many other smaller deformations which follow these circles, many other lesser circles between, and possibly some larger circles. The distance between these major circles is similar, but not uniform.
     This stepping of the river valleys as shown here, seems to be fairly common. To see this across the United States from another direction, see Mt. Burdett, in British Columbia.  Another example of this can be seen with the Mueda Impact as it passed through South Africa.

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