Seisan meets Java

Lars Ottemoller1) and Jens Havskov2)

1) British Geological Survey, UK2) University of Bergen, Norway

Background

• Development started in late 80s• Large number of contributors• Steady improvements, now Version

8• However, basics unchanged• Low funding, most contributions

through personal initiative

Functionality

• Routine analysis of earthquake data: Database and formats Plot and analyse signals Earthquake location and

magnitude Fault plane solution Catalogue search Bulletin Seismicity maps

• Research Tools

Philosophy

• Open source• Non-commercial• Multi-platform • Open system• Integrate essential tools into one

package• Documentation• Support

Users

• Local and regional observatories in all parts of the world (~100)

• Widely used in the developing world

• Individual researchers• 15% of data sent to ISC in Seisan

format

Training

• University of Bergen, seismology courses• Potsdam course• Pre-conference courses (IASPEI, ASC, ESC)• Regional projects (Central America, Africa)• RELEMR project• Commercial projects (India, Venezuela,

Guatemala)

• Tutorial and test data distributed with software

Success ?

• ConsPoor graphicsMost programs without GUIMostly written in FortranAdvanced signal processing features

limited

Success ?

• ProsFree and open sourceMulti-platform (especially Windows)Reasonable documentationEasy to installComplete system (providing all tools needed

at many observatories)Easy integration of different data-sets

Good support

Seisan and Java

• SeisWeb (web based processing)

• Jseisan (local processing)• SeisConf

Developer: Bladimir Moreno

Client-server based architecture

Processingsoftware

Database

SeiswebJseisan(GUI)

Commands

Data

Script

Server sideSeisWeb: Web server

JSeisan: Local machine

Client side

Discussion client-server based architecture

• Tool can run with various processing/database systems

• Maximizes use of server side software• Compatibility of results• Minimizes size of client-side software• Compression required, high exchange

rate between client and server

Implementation

• SeisWeb/JSeisan independent of Seisan

• Basic functionality of Seisan• Easy to use GUI also by non-

professional• Data formats: GSE and Nordic• Security

Experience

• Java tools do provide improved GUI to Seisan

• Processing across web feasible• Graphics platform dependant• Java tools not the fastest• Hardly any user feedback• Users seem to continue with

traditional tools

Future ?

Seisan• Continue support• Minor modifications and some new

features

Java• Combine SeisWeb and Jseisan• Further development dependent on users’

acceptance

Demonstration

• Convert Orfeus SEED file to Seisan and enter into database

• Plot and analyse event (non-Java tools)• Location and magnitude• JSeisan

access to databaseAnalysis

• SeisConf• Linux & Windows