VISTAPRO LANDSCAPE FILES

VISTAPRO LANDSCAPE FILES
Most of the landscape DEM files were obtained from the USGS and are accurate to within 7 meters. Some of the files were assembled to fit into Vistapro and therefore may not be perfect where they are joined.
ELCAP.DEM
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ElCap is a section of Yosemite Valley in California out of which rises El Capitan, a very large (about 1000 meters) granite cliff formation at coordinate 2520,5760 (X, Y) in the DEM data. This landscape was created by joining together two USGS DEM files and then clipping out the section of interest. A small "scar" that runs North/South where the USGS data did not quite line up can be seen. The joining scar is most apparent in the Valley with the sun shining from the east or west at approximately 3400,4980. This DEM file is as accurate as the original USGS data.
HALFDOME.DEM
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The Half Dome section of Yosemite Valley contains the famous granite formation know as Half Dome at location 5100,7260. The method used by the USGS to digitize the terrain led to some distortion at the top and edges of Half Dome. The jaggy bump at the top of Half Dome is a USGS artifact. This DEM file is as accurate as the original USGS data since it was simply clipped out of one DEM file.
CRATERL.DEM
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Crater Lake is the caldera of an ancient volcano in Oregon. The walls of the caldera rise approximately 1250 meters from the bottom of the lake to the top of the caldera. The DEM data includes the underwater elevations. The lake fills the caldera to a level about half way up the walls. The mound near the west edge of the caldera is Wizard Island. It is separated from the edge by the lake. The circular mound near the top of the caldera is completely submerged. The lake can be filled with water using the Lake function of Vistapro. Clicking the mouse button about halfway from Wizard Island to the edge of the caldera gives approximately the right water level. In order to include the entire lake in the file, everything was adjusted down by a factor of 0.6. Therefore, to convert elevations or distances into actual meters, take the values given by Vistapro and divide them by 0.6.
MSHB.DEM and MSHA.DEM
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Mt. St. Helens is the volcano in Washington that blew its top on May 18, 1980. The explosive eruption was preceded by amounts of intense earthquake activity. A 150 meter bulge started to grow in April at a rate of 5 meters per day. A magnitude 5.1 earthquake set into motion the collapse of the bulge and the following explosion. Winds from the blast were calculated at 670 miles per hour. Almost everything within 8 miles of the blast was obliterated. Virtually all trees were flattened at distances up to 19 miles from the volcano. Significant amounts of volcanic ash fell as far as one thousand miles away. The new crater is about 3 kilometers wide and 700 meters deep. The "before" data was generated from stereo photographs taken in 1979. The "after" data comes from photographs taken late in 1980.
MONS.DEM
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Olympus Mons is a huge volcano on the surface of Mars that is roughly twice as tall as Mt. Everest on earth! It is about 500 kilometers in diameter and rises approximately 18 kilometers above the surrounding landscape. The original DEM file which contains the entire volcano is over 4 megabytes! The DEM file included here contains only the interesting caldera portion of the volcano. The technique used by the USGS to generate this kind of extra-terrestrial data creates extensive artifacting resulting in raked lines in the landscape. One or two smoothing passes will remove these artifacts. The data on the vertical axis is exaggerated by 4 fold to make the landscape more dramatic. Elevations are measured from an arbitrary reference, because there is no sea level on Mars.
JULIA.DEM and MANDELBR.DEM
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Julia and Mandelbrot landscapes are artificially generated by a mathematical algorithm. The user may have seen Julia sets and Mandelbrot sets displayed as colors on a 2-D screen. If the user has a Mandelbrot generating program that will handle Julia sets, or a Julia generating program, the locations are as follows: The Mandelbrot is 1.255525 real -0.381060 imaginary, with a diameter of approximately 0.007; the location of the Julia set is 0.75 real -0.11 imaginary, relative to the Mandelbrot set.
ARROWHD.DEM
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This is the Lake Arrowhead region of the San Bernardino Mountains in Southern California. The low-lying region forms a lake that is in the shape of an arrowhead, hence the name. The lake was formed by the addition of a man-made dam, which is not part of the DEM data, so it is impossible to fill the lake without flooding the landscape below. This is clipped from a larger data set that is also available from VRLI, called "Lake Arrowhead and Environs".
VANTAGE.DEM
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This is a portion of the Columbia River in the state of Washington that forms the north portion of Wanapum Lake. It is located in Ginkgo State Park near Vantage, Washington.
SANLUISO.DEM
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This is the area that we see when we look out our windows. VRLI is located toward the southeast portion of the topographic map. The mountains are not of spectacular height, but it forms quite a pleasing landscape.
SANGORGO.DEM
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This is south of the Big Bear Lake region of the San Bernardino Mountains in Southern California. It contains Mt. San Gorgonio, a 3500 meter peak in an area known as the San Gabriel wilderness. This is clipped from a larger data set that is available from VRLI, called the "San Gorgonio Mountain and Environs".
BIGSUR.DEM
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This is the Big Sur area along the coast of north central California, just south of the Monterey Peninsula. It contains the Pfeiffer Big Sur National Park. It is one of the more beautiful camping areas in California, and contains one of the southernmost groves of redwoods. It is clipped from a larger data set that is available from VRLI, called "Big Sur and Environs".
MORROBAY.DEM
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This is the data set for Morro Bay, one of our local tourist attractions on the central coast of California. There is a large rock that juts up into the fog called Morro Rock. This is visible as a mound in the northwest corner of the topographic map.
MTBALDY.DEM
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Contrary to popular belief there is no such mountain as Mt. Baldy in southern California. That is the name of the village on the slopes of Mt. San Antonio. This is located in the San Gabriel mountains south of Wrightwood. This has been clipped from a larger data set that is available from VRLI, called "Mt. Baldy and Environs".
MTADAMS.DEM
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This contains Mt. Adams, in the southern portion of Washington State. It is part of the Mt. Adams Wilderness, and is a good example of a volcano, reaching from a height of over 3700 meters at its peak. It was clipped from a larger data set that is available from VRLI, called "Mt. Adams and Environs".
WOODSH.DEM
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This is the first of our undersea data, a volcanic region located at 21 degrees 13 minutes north and 166 degrees 24 minutes east, 500 miles north of Wake Island. This is actually several thousand meters below sea level, but has been scaled to appear above sea level for rendering purposes.