Subject: monograph
Resent-Date: Mon, 08 Nov 1999 17:07:45 -0500
Resent-From: Geoffrey Fox <gcf@npac.syr.edu>
Resent-To: p_gcf@npac.syr.edu
Date: Fri, 05 Nov 1999 17:21:05 -0800
From: "Kenneth J. Hurst" <hurst@cobra.jpl.nasa.gov>
To: Geoffrey Fox <gcf@npac.syr.edu>

Geoffrey -

I am sending what I have so far for the gem mongraph chapter.
It seems very rough and rather small quantity. I am having
a hard time deciding what to write.
One piece describes the GEMCI.
The second and third I think you have already seen -
an example of using the GEMCI for earthquake modeling
and an example of using it for earthquake response.

========
Current GEM Computational Components

The first step in building the GEMCI has been to inventory the
computer codes currently available in the community. A summary of
the results of this inventory is maintained at
http://milhouse.jpl.nasa.gov/gem/gemcodes.html and the status
as of the time of writing is in Table 1.

The catagories covered by the existing codes include
codes for understanding dislocations:
elastic models - both half-space and layered,
viscoelastic models,
finite element and boundary element codes,
and
inversion codes;
codes for understanding how faults interact:
cellular automata,
finite element and boundary element codes,
fault friction models;
codes for understanding the dynamics of the earthquake rupture itself:
and
codes for displaying the results of various simulations.

The second step is to start to define the building blocks
of exchange formats and web interfaces which will allow
each of the pieces of the GEMCI to work together.
To that end, we have implimented a prototype system
which uses a few of the pieces.

Insert words (I think already written) from Jay, Ken, or Tom
describing what was done.

The goal was to create something which would be useful in its own
right, but which initialy had a limited scope so that it could
be accomplished in a short amount of time.

                                        Appendix 1

                                 Short Descriptions Grouped by Type

Elastic
        3D-DEF -- Performs elastic dislocation boundary-element calculations
        coulomb -- Computes 3D elastic dislocation & 2D boundary element stress and strain
        DYNELF -- Models 3D elastodynamic finite difference with frictional faults
        faultpatch -- Generates earthquake sequences, given fault geometries and loading rates using Cellular automata methods.
        FLTSLP -- Inverts groups of focal mechanism solutions or slickenline data for orientation and relative magnitudes of principal strain rates
      and for relative micropolar vorticity.
        GNStress -- Model stresses induced by faulting, for studying fault interaction.
        layer -- Calculates surface displacements and strains for vertical strike-slip point source in horizontal layer above half-space.
        RNGCHN -- Calculate surface displacements and strains in elastic half space.
        scoot -- 2D elastodynamic finite difference with frictional fault
        simplex -- 3D inversion of geodetic data for displacement on faults.

Viscoelastic
        DYNELF -- Models 3D elastodynamic finite difference with frictional faults
        FLTGRV and FLTGRH -- Compute 3 vector components of surface displacement from slip on a dipping thrust fault contained within an
      elastic layer overlying a viscoelastic-gravitational half space.
        STRGRH and STRGRV -- Computes 3 vector components of surface displacement from slip on a dipping strike slip fault contained within
      an elastic layer overlying a viscoelastic-gravitational half space.
        Virtual_California -- Realistic cellular automata (CA) viscoelastic earthquake simulator.
        VISCO1D -- Computes viscoelastic spherical deformation due to faulting or dike emplacement.

Cellular Automata
        faultpatch -- Generates earthquake sequences, given fault geometries and loading rates using Cellular automata methods.
        Virtual_California -- Realistic cellular automata (CA) viscoelastic earthquake simulator.

Dynamic
        DYNELF -- Models 3D elastodynamic finite difference with frictional faults
        scoot -- 2D elastodynamic finite difference with frictional fault

Inverse
        FLTSLP -- Inverts groups of focal mechanism solutions or slickenline data for orientation and relative magnitudes of principal strain rates
      and for relative micropolar vorticity.
        simplex -- 3D inversion of geodetic data for displacement on faults.
        qoca

Visualization
        VelMap -- Aid for visualizing displacement and velocity of crust.

=====

Ken Hurst
Mail Stop 238-600                       voice: 818-354-6637
Jet Propulsion Lab / Caltech            FAX:   818-393-4965
Pasadena, CA 91109                      hurst@cobra.jpl.nasa.gov