This image was generated using the digitally combined bathymetry and DEM data for the area. A bathymetry and DEM data set can be used as input to various enhancement and analysis procedures. One of these procedures allows us to generate a 'shaded relief' image with the sun positioned at any desired elevation and azimuth. A shaded relief enhances the topographic structure in the data, and can be used to extract spatial features, such as surface fractures, faults, folds, and drainages. Several major landmarks can be seen in this image, including the San Andreas fault/rift zone and Monterey Canyon. This image is presented in compressed mode for comparison with both the black and white and color coded images below (north is toward the left). The full resolution version of this shaded relief image is presented later in this web page.
One way to show the elevation relationships within an image is to generate a perspective view. Basically, this is a procedure that allows the 'viewer' to be positioned somewhere other than directly above the image (as in the image above). In this particular image, the viewer has been positioned to the west of the image at an elevation angle of twenty-five degrees above the ocean (sixty-five degrees from directly above). The topographic relationships between the on-land mountains, ocean shelf, slope, and basin are easily seen in this image.
This is the same perspective view image shown above, but with the color coded bathymetry and DEM image digitally combined with the shaded relief. By digitally combining the two image products, both the elevation and structural information can be displayed in the same image. The bathymetry and DEM data were color coded to cover the elevation range from -4000 to +1400 meters.
This is the same shaded relief image shown above, but at full rather than compressed resolution. Click inside any of the rectangular grids to display that area at full resolution. The level of detail present in the full resolution image is superior to that in the compressed version above. Notice the information contents related to surface fractures, faults, folding, and drainage patterns (north is toward the top).
![[3-D]](https://webarchive.library.unt.edu/eot2008/20090109024742im_/http://terraweb.wr.usgs.gov/icons/3dglassb.gif){kind=icon}
This is also the shaded relief image at full resolution, however, the bathymetry and DEM data were used to create a stereo pair. Parallax was introduced into the shaded relief image in the horizontal direction using the bathymetry and DEM data to generate the stereo image. The stereo/3-D affect can be viewed by using red and blue or red and green (red on the left) glasses. This is an excellent way to study and analyze the topographic component of an area and show the regional structure. Note how well the San Andreas fault/rift zone, Monterey Canyon, and other surface landforms are expressed in the '3-D' image.
Related Pages:
Back to Central California DEM and Bathymetry Images
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