The SCEC Crustal Deformation Working Group (Group E) is pleased to announce the availability of a new version of the Crustal Deformation Velocity Map.

The entire contents of the new release version are available on the web at the following URL:

This new solution results from an analysis of nearly all of the EDM, VLBI, and SCEC-archived GPS data (both survey and continuous mode) acquired for southern California between 1970 and 1997.

The maps and accompanying tables include new estimates of the horizontal velocities for 363 stations. Uncertainties in these estimates are less than 5 mm/yr. For stations close to the Landers epicenter, we provide estimates of both the pre- and post-Landers velocities.

Important differences between Release 2.0 and Release 1.0 (October 1996) of this SCEC product are as follows: 1) the direct use of the VLBI data, and 2) the addition of several additional sets of GPS data:

These additions of data incorporated into the new solution have added 76 stations to the map, and have reduced 2/3 of the station velocity uncertainties to about 1 mm/yr.

For a discussion of planned continuing work on improving the velocity map, please see our group's 1997-1998 Annual Report, available on the web at:

We hope that our colleagues within and outside of SCEC will find this second release of the SCEC Velocity Map useful in their research. We'd be very pleased to have your comments, suggestions, and critical evaluations of this SCEC product.

This message is sent on behalf of members of the Crustal Deformation Working Group, and in particular those who have contributed to bringing this new version of the velocity map to completion (as noted in the 'Credits' section of the release notes).