loma_prieta.hqx  212 Kb

     This report contains instructions and patterns for preparing a
three-dimensional model that schematically illustrates the fault motion that
occurred during the Loma Prieta earthquake of October 17, 1989, in
California.  The model is intended to help students and others visualize the
process of fault slip during earthquakes. By constructing and examining this
model, students will be better able to visualize fault motion on this part
of the San Andreas fault and will have a better understanding of how the
natural landscape evolves.
     
     Although a small-scale paper model cannot do justice to the complexity
of the deformation that accompanied the Loma Prieta earthquake, a model can
serve as an aid in visualizing the faulting process and in understanding how
a fault that did not rupture the surface of the darth could produce a zone
of open fissures, as was observed a long the San Andreas fault above the
northern end of this earthquake.

     The date of this Open-File Report is November 20, 1989 (version 1).
OF89-640-A, paper copy, 10 p.  OF-640-B, 3.5-in. diskette.

     The date of version 2 of this Open File Report is Feb. 7, 1992.    
OF 89-640-A, paper copy, 11p.  OF 89-640-B, 3.5-in. diskette. 

     Purchasers of the diskette version 2 of this report, which includes all
of the text and graphics, can use HyperCard 2.0 software (not supplied) to
change the model (by adding geologic patterns, symbols, colors, etc.) or to
transfer the model to other graphics software packages.

    Requirements for the diskette version 2 are: Apple Computer, Inc.,
HyperCard 2.0  software, and an Apple Macintosh  computer.  If you are
using System 7, we recommend using  at least 3 MB of RAM with 1.5 MB of
system memory available for HyperCard.
     To see the entire page (card size: MacPaint), select "Scroll" from "Go"
menu  and move the hand pointer in the scroll window.
     If you are experiencing trouble with user-level buttons, select
"message" from the "Go" menu. Type "magic" in the message box and press
return. Three more user-level buttons should appear.

     To order this report, contact:  U. S. Geological Survey Books and
Open-File Reports Sales, P.O. 25425 Denver, CO. 80225, or call (303)
236-7476.