XML-SEED format and its application to synthetic seismogram database

Seiji Tsuboi

IFREE/JAMSTEC

XML Representation of SEED format

• eXtensible Markup Language (XML) is a text-based language.

• XML documents use `tags’ to establish hierarchical data structure and named values.

• XML can be used for most of all major platforms.

• XML is a basic technology for networking.

Advantages of using XML

• Header structure of SEED is modular, which can be easily represented by XML.

• Data structure of XML is flexible, because length of any fields is not fixed.

• XML has its schema language –XML-Schema, which can be used for validation of XML document.

SEED Format Organization

• Control headers (formatted in ASCII)

information about the volume, the station-channels, and the data

• Time series (binary, unformatted)

seismic waveform data

Conversion of control header <?xml version="1.0" ?> <xseed> <volume_control_header> <!--For blockettes in volume control header --> </volume_control_header> <abbreviation_dictionary_control_header> <!--For blockettes in abbreviation dictionary control header --> </ abbreviation_dictionary_control_header > <station_control_header> <!--For blockettes in volume control header --> </station_control_header> <timespan_control_header> <!--For blockettes in volume control header --> </timespan_control_header> </xseed>

http://www.jamstec.go.jp/pacific21/xmlninja/

Synthetic seismogram database

• Synthetic seismograms, which are accurate up to 5 sec and longer, will be calculated by Spectral-Element Method on the Earth Simulator for fully 3-D Earth model.

• Database will be created for all the broadband seismograph stations over the globe.

• Minimum magnitude of the earthquake will be chosen considering the available CPU time (currently Mw>6.5).

XML-SEED format for synthetics

<xseed> <volume_index> <identifier> <timespan_index> </volume_index> <method> <method_type>SEM</method_type> <SEM_parameters> </method> <events> <event> <moment_tensor> </events> <networks> <stations> <channels> <dictionary> <data_record></xseed>

XML-SEED format for synthetics

<data_record> <data_record_type>GLOBAL</data_record_type> <GLOBAL_data_header> <station_identifier> <channel_identifier> </GLOBAL_data_header> <GLOBAL_chunk>-2.904506e-18 -6.672627e-18 -6.978924e-18 … </GLOBAL_chunk></data_record>