Online Geochemical Database Resources for Teaching: The Subduction
Factory and Beyond
www.earthchem.org
Karin A. Block, Kerstin A. Lehnert, and Annika Johansson, Lamont-Doherty Earth Observatory of Columbia University 61 Route
9W Palisades, NY 10964
Teaching with Real Data
The availability of online resources in teaching has
changed the way educators engage students by
providing easy access to the data currently being used in
scientific investigations. Online geochemical databases
enable instructors to teach about complex geochemical
systems such as processes that occur at subduction
zones using an inquiry-based approach. The use of real
data provides an opportunity for students to explore the
scientific process in creating hypotheses a plan for
investigation while simultaneously learning about plotting
tools, interpretation of graphs, and formulation of
conclusions based on their observations.
Retrieving a MARGINS (or any geochemical) dataset:
A user can query member databases through the
EarthChem Portal. Queries can be defined by rock type,
publication reference, chemical parameter and location.
Once the user is satisfied with data selection, the
advanced output provides options for viewing data quality
(metadata) and download of the dataset. The example
below shows how to retrieve a dataset from the Izu-BoninMariana Focus Site of the Subduction Factory that
includes GEOROC and PetDB data.
Query
Visualization Tools EarthChem
Plotting tools available through the
EarthChem Portal provide immediate
visualization of datasets and encourage
conclusions based on first-hand
observations. Datapoints are linked to
sample data in the source database for
further exploration.
PetDB SedDB
Deep Lithosphere
Dataset
NAVD GEOROC
Relational Geochemical Databases - Data and Metadata
AT
The online databases, PetDB, SedDB, NAVDAT and GEOROC
provide geochemical data of the various input and output
components at the Subduction Factory Focus Sites.
Application of these resources in teaching using real data
presents the challenge of integration of data output in different
formats in order to make the dataset usable in visualization
applications. Additionally, SedDB and the EarthChem Deep
Lithosphere Dataset provide access to geochemical data
relevant to Source-to-Sink (S2S) and Rupturing the
Continental Lithosphere (RCL) MARGINS efforts.
View
Visualization Tools GeoMapApp
Download
Students can explore chemical variations such as MgO concentration
along the arc and relate the data to subduction geometry through
integration with GeoMapApp bathymetry, topographic profiles and 3D
renderings.
EarthChem Portal: Discovery, Access, & Visualization
A
The EarthChem web portal offers distributed searches across
a federation of geochemical databases for easy discovery and
accessibility of geochemical data. A prototype was released in
August 2006 that allows distributed queries to PetDB,
NAVDAT, and GEOROC. The EarthChem Portal features
standardized and integrated data output format, map
interfaces, and tools for data quality assessment and data
analysis and visualization. In the next development phase,
sedimentary data from SedDB, PaleoStrat, and Pangaea will
be linked to distributed searches, enabling educators and
researchers to explore a full range of geochemical data
associated with the MARGINS Subduction Factory
Supported by the U.S. National Science
Foundation
GeoMapApp Access to EarthChem
A periodically EarthChem dataset
can be accessed and visualized in
GeoMapApp by searching
>Available Datasets>NSF Focus
Sites or by entering keyword
‘earthchem’ in the searchable list of
datasets.
A Web Feature Service is under
development to provide real-time
versions of EarthChem data
through GeoMapApp.
A’
Left: Data layers from EarthChem and SedDB. Red circles
are stations from PetDB and GEOROC downloaded from
EarthChem. Yellow circles are stations from SedDB.
Above: Topographic profile along line A-A’
Additional resources available through the Marine Geoscience Data
System (MGDS) provide alternative views of the subduction zone from
seismic reflection.
Seismic data from UTIG obtained via MGDS Data Link http://marinegeo.org