Seismo-Surfera tool for collecting, querying, and mining

seismic data

Yannis TheodoridisUniversity of Piraeus

ytheod@unipi.gr

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Outline of the presentation

Concepts and motivationThe Seismo-Surfer tool Architecture Functionality Current status

Future workConclusions

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Concepts and motivation (1)

Seismic data are recorded by seismologists (geologists etc.) in order to study tectonic activity. This kind of data is characterized by several attribute types alphanumeric (e.g. magnitude) spatial (epicenter, depth) temporal (time of occurrence)

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Concepts and motivation (2)

Goal: to build a prototype system (tool) of practical impact that combines results of latest research trends in the fields of Non-traditional databases (spatio-temporal) Data warehousing Data mining

by using state-of-the-art DBMS technology.

… all this into a user-friendly environment.

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Concepts and motivation (3)

Such a tool could be useful to researchers of geophysical sciences (e.g. for

constructing seismic profiles). key personnel in public administration (e.g. for

visualizing epicenters and relating them with other spatial entities).

simple users (e.g. web-surfers seeking for maps of seismic activity).

The Seismo-Surfer tool

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Seismo-Surfer Architecture

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Seismo-Surfer Functionality (1)Non-traditional queries (spatial and spatio-temporal)

“find all epicentres of earthquakes within distance no more than 50Km from Athens in the last 10 years”

Data warehouse functionality by supporting summarized views of data in different levels of abstraction

spatial (e.g. province, country, continent) temporal (e.g. month, year, ten year period)

Data mining operations finding / visualizing clusters seeking association rules

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Seismo-Surfer Functionality (2)

Remote data sources integration (e.g. from the web).

Example: only summaries of seismic data could be stored locally and additional data could be loaded, from the remote (web) source, on demand

Phenomena extraction Example: automatic extraction of semantics from

stored data, such as o the main shock ando possible intensive aftershocks in shock sequences

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Seismo-Surfer Current Status (1)

A prototype has been implemented using Oracle (9i DB & Spatial Data Cartridge) and Java technologies.Two web sources have been integrated and the local database is auto-updated

Greek events (source: Inst. of Geodynamics @ the Nat’l Observatory of Athens www.gein.noa.gr )

Global events (source: US Geological Survey www.usgs.gov ).

Extra map layers with geographical entities of Greece (populated places, islands etc.) have been also integrated.

(source: US NIMA www.nima.mil )

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Seismo-Surfer Current Status (2)

Current functionality includes Spatiotemporal Queries (exploiting the R-tree

indexing technique): Range queries (epicenters in a region) Nearest-Neighbor Queries (epicenters closest to a point

on the map) Distance Queries (epicenters at a distance lees than X) Closest-Pair Queries (epicenters closest to Greek cities)

(cont’d)

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Seismo-Surfer Current Status (3)

(cont’d) Data Mining Operations

Currently, a single clustering algorithm (k-means) Various visualization features

Maps, plots and GUI tools that assist the user to the query formulation process and allow viewing the selected or analyzed data in a number of different ways.

Screenshots …

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1) Spatio-temporal queries

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1a) Closest-pair queries

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2) Clustering

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3) Plotting facilities

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Future WorkData warehouse functionality summarized views of data

spatial (e.g. province, country, continent) temporal (e.g. month, year, ten year period)

aggregations stored locally; detailed data fetched from web sources, on demand

More data mining operations more clustering techniques algorithms for classification and

correlation rulesMore data sources and layers

‘smart’ filters for feeding local DB Semi-structured data?

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Conclusions

Seismo-Surfer is a prototype data management and mining system for seismic dataCombines latest research trends in database management, data warehousing and data miningIntegrates data from remote (web) sourcesTwo versions will be available soon: A desktop version of full functionality A web interface (light version)

For more information:http://isl.cs.unipi.gr/seismo/