Greetings,

I am pleased to announce the release of PyLith 2.2.1, a finite-element
code designed to solve dynamic elastic problems and quasi-static
viscoelastic problems in tectonic deformation.

This release provides a few new examples and bugfixes.

You can download the source code and binaries from

    https://geodynamics.org/cig/software/pylith

Detailed installation instructions for the binary packages are in the
User Manual with detailed building instructions for a few platforms in
the INSTALL file bundled with the PyLith Installer utility. We also
offer a Docker image
(https://wiki.geodynamics.org/software:pylith:docker) for running
PyLith within a portable, virtual Linux environment.

======================================================================
MIGRATING FROM VERSION 2.1 TO 2.2
======================================================================

No changes are needed to parameter or other input files. The default
format for pylithinfo output is now JSON.

======================================================================
RELEASE NOTES
======================================================================

* Added new examples.

    - examples/3d/subduction: New suite of examples for a 3-D
      subduction zone. This intermediate level suite of examples
      illustrates a wide range of PyLith features for quasi-static simulations.

    - examples/2d/subduction: Added quasi-static spontaneous rupture
      earthquake cycle examples (Steps 5 and 6) for slip-weakening and
      rate- and state-friction.

    - These new examples make use of ParaView Python scripts to
      facilitate using ParaView with PyLith.

* Improved the PyLith manual

    - Added diagram to guide users on which installation method best
      meets their needs.

    - Added instructions for how to use the Windows Subsystem for
      Linux to install the PyLith Linux binary on systems running
      Windows 10.

* Fixed bug in generating Xdmf files for 2-D vector output. Converted
  Xdmf generator from C++ to Python for more robust generation of Xdmf
  files from Python scripts.

* Updated spatialdata to v1.9.10. Improved error messages when reading
  SimpleDB and SimpleGridDB files.

* Updated PyLith parameter viewer to v1.1.0. Application and
  documentation are now available on line at
  https://geodynamics.github.io/pylith_parameters. Small fix to insure
  hierarchy path listed matches the one for PyLith.

* Updated PETSc to v3.7.6. See the PETSc documentation for a summary
  of all of the changes.

* Switched to using CentOS 6.9 for Linux binary builds to insure
  compatibility with glibc 2.12 and later.

See CHANGES in the top-level source directory for a list of changes
for each prior release.
