 Figure 1 |
HoloDraw is free software that helps you make rotating 3D images from your data. Downloads for Unix, Mac or Windows are available at http://holodraw.org. The images you make with HoloDraw can be viewed on a GeoWall in stereo 3D, or in a web browser with the free Cortona plug-in from http://www.parallelgraphics.com/products/cortona/ or Cosmo Player from http://ca.com/cosmo/html/player.htm. HoloDraw is designed to read many common data formats including X-Y and X-Y-Z points, lines or surfaces. You can also represent a fourth attribute as a color. For example, the X-Y-Z values might be the hypocenter of an earthquake, while you use color to represent the magnitude, date, or some other type of information about each quake (Figure 1). It can be very easy to convert your data to HoloDraw format. For example, a HoloDraw file to plot three points might look like this: point:270.3 9 -2790 point:268.0 0.4 -2415 point:270.5 6 -2760 Several HoloDraw programs exist to help format your data, or you can even do it with, for example, Unix commands such as sed or awk. HoloDraw works hand-in-hand with Generic Mapping Tools (GMT) maps and scripts. Figure 2 shows a pscoast map plotted above other data, using HoloDraw. GMT maps can now be fully rotated and zoomed in real time stereo 3D. Figure 3 shows a GMT surface plot integrated within a HoloDraw image. HoloDraw also recognizes GMT Color Palette Tables (".cpt" files.)
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 Figure 2 |
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 Figure 3 |
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References
GeoWall - Daniel Steinwand, Brian Davis, Nathan Weeks, "GeoWall: Investigations into Low-cost Stereo Display Systems", 2002 USGS Open File Report.
GMT - Wessel, P. and W. H. F. Smith, New, improved version of the Generic Mapping Tools released, EOS Trans. AGU, 79, 579, 1998. Global tomography - Grand, S.P., Mantle shear-wave tomography and the fate of subducted slabs, Philosophical Transactions of the Royal Society of London Series a- Mathematical Physical and Engineering Sciences, 360 (1800), 2475-2491, 2002. Hotspot map - Thorne et al. 2003, PEPI, in press. South Africa tomography - Fouch, M.J., D.E. James, J.C. VanDecar, S. van der Lee, and the Kaapvaal Seismic Group, Mantle seismic structure beneath southern Africa, S. African J. Geol., in press, 2003. Japan raypaths - Bernot, C.M., and M.J. Fouch, Shear wave splitting and mantle flow beneath Japan, to be submitted to Geophys. Res. Lett., 2004. Hypocenters - E.R. Engdahl, Van der Hilst, R.D., and Buland, R.P., 1998, Global teleseismic earthquake relocation with improved travel times and procedures for depth determination, Bull. Seism. Soc. Amer., v. 88, pp. 722-743. Bouncing raypaths - Lay et al. 2003, GRL, in preparation Ribbon plot - Thomas, C.H., Garnero, E.J, Lay, T., Highly variable topography beneath the Cocos plate from frequency-wavenumber migration of broadband S and ScS waves, in prep., 2003. |
