Web-based technology for storage and processing of multi-component data in seismology

Seismic databases and processing tools currently available are
mainly limited to classic three-component seismic recordings and
cannot handle collocated multi-component, multi-disciplinary
datasets easily. Further, these seismological databases depend on
event-related data and are not able to manage state of the art
continuous waveform data input as well. None of them allows for
automated request of data available at seismic data centers or to
share specific data to users outside one institute. Some seismic
databases even depend on licensed database engines, which
contradicts the open source character of most software packages
used in seismology. This study intends to provide a suitable answer
to the deficiencies of existing seismic databases. SeisHub is a
novel web-based database approach created for archiving,
processing, and sharing geophysical data and meta data (data
describing data), particularly adapted for seismic data. The
implemented database prototype offers the full functionality of a
native XML database combined with the versatility of a RESTful Web
service. The XML database itself uses a standard relational
database as back-end, which is currently tested with PostgreSQL
(http://www.postgres.org) and SQLite (http://www.sqlite.org). This
sophisticated structure allows for the usage of both worlds: on the
one hand the power of the SQL for querying and manipulating data,
and one the other hand the freedom to use any standard connected to
XML, e.g. document conversion via XSLT (Extensible Stylesheet
Language Transformations) or resource validation via XSD (XML
Schema). The actual resources and any additional services are
available via fixed Uniform Resource Identifiers (URIs), where as
the database back-end stores the original XML documents and all
related indexed values. Indexes are generated using the XPath
language and may be added at any time during runtime. This
flexibility of the XML/SQL mixture introduced above enables the
user to include parameters or results as well as meta data from
additional or yet unknown monitoring techniques at any time.
SeisHub also comprises features of a “classical seismic database”
providing direct access to continuous seismic waveform data and
associated meta data. Additionally, SeisHub offers various access
protocols (HTTP/HTTPS, SFTP, SSH), an extensible plug-in system,
user management, and a sophisticated web-based administration
front-end. The SeisHub database is an open source project and the
latest development release can be downloaded via the project home
page http://www.seishub.org. The SeisHub database has already been
deployed as central database component within two scientific
projects: Exupéry (http://www.exupery-vfrs.de), a mobile Volcano
Fast Response System (VFRS), and BayernNetz, the seismological
network of the Bavarian Seismological Service (Erdbebendienst
Bayern; http://www.erdbeben-in-bayern.de).