Exploring Geochemistry in the Classroom Using GEOROC DataAccess the data from the GEOROC Homepage (more info) .
The Geochemistry of Rocks of the Oceans and Continents (GEOROC) is a database that provides chemical and isotopic data for rocks, minerals, and melt/fluid inclusions. GEOROC data is from multiple geological settings including convergent margins, ocean islands, seamounts, oceanic plateaus, submarine ridges, ocean-basin flood basalts, continental flood basalts, archean cratons, greenstone belts, and intraplate and rift volcanics. The site contains analyses for over 150,000 rock, mineral, and inclusion samples. Users can search the database by bibliography, tectonic setting, geographic coordinates, chemistry, or petrography.
Use and Relevance
Geochemists study the distribution of all of the known elements in this universe. Many of them study the composition of rocks and minerals on Earth and why they are found where they are. GEOROC is useful to anyone interested in geochemistry because it provides important geochemical data on volcanic whole rocks, minerals and inclusions and Archean cratons from various locations around the world. The data can be used to analyse and classify samples, compare similar rocks from different parts of the world, compare compositionally varied rocks from geographically similar settings, learn the name of a rock using information about it's composition, or to try and understand what a collection of elements experienced before solidifying into their current distribution to create a rock or mineral. Geochemists can also combine elements in new distributions to create new materials that could be used in our everyday lives.
Use in Teaching
- Volcanic and plutonic igneous rocks
- Mantle xenoliths
- Volcanic glasses
- Metamorphic rocks
- Inclusions (glass, minerals, and fluid)
- Generating graphs from raw data (using programs such as Excel)
- Interpreting petrological data (including chemical composition of rocks in % weight and ppm)
- Examining the function of plate tectonics in the formation of igneous rocks
Igneous Rock Compositions and Plate Tectonics
- Generating "Harker" diagrams to analyze compositional changes and make petrologic interpretations
- Learning to think like a scientist
Exploring the Data
Data Type and Presentation
Data is presented as tables in HTML format and can be downloaded as an Excel compatible (comma delimited text) format.
Accessing the Data
Users can query data by bibliography, tectonic settings, geography, chemistry, or petrography (including volcanic rocks, plutonic rocks, and mantle xenoliths). Once a query path is chosen, data sets can be further refined by a variety of selection criteria, including rock type (e.g., volcanic), rock name (e.g., alkali basalt), and chemical composition. There is also a collection of precompiled files that can be downloaded as .csv files for use in Exel.
Manipulating Data and Creating Visualizations
Raw data can be be used to generate graphs and diagrams.
Tools for Data Manipulation
Spreadsheet and graphing programs like Exel can be used to manipulate the data.
About the Data
Collection methods vary greatly. For some data sets, the collection method (such as dredging or drilling) is indicated, but this information is not provided for all data sets. References associated with data sets are given and users could search through primary literature for details regarding collection methods and analyses.
Limitations and Sources of Error
Age data is not consistently given in all data sets. Sources of error are not directly given in the datasets, and therefore the references given should be examined by users who would like information regarding data limitions and sources of error.
References and Resources
Scientific References that Use this Dataset
- List of papers that reference the GEOROC database.
- GEOROC - Current and Upcoming Activities
- Progress in the GEOROC Database - Fast and Simple Access to Analytical Data by Precompilation
Other Related Scientific References
- GEOROC provides a reference list (associated with datasets) that can be downloaded in Excel and a list of papers that refer to GEOROC data.
Other related Education Resources
- Insights on WWW-based geoscience teaching: Climbing the first year learning cliff : Discusses use of databases in teaching petrology.