EarthChem Portal Help

Setting constraints on sample selection

You can set any combination of the following:

  1. Reference and Keyword Search: Use this query parameter if you know the specific year, author, journal, or keyword that contains the data you are looking for.
  2. Location: The location query allows you to retrieve data by selecting an area on a map by defining a polygon, inputting specific geospatial coordinates, or by browsing geographic locations defined in the EarthChem Gazetteer.
  3. Rock Type:  Search by material type and associated rock types using names provided in the publication or by TAS diagram classification.
  4. Chemistry:  Query the global dataset for specific chemical items and range of values. 
  5. Glossary: Click on the left-hand menu to search by glossary item or define your own. Simply register or login to create a reusable query.
  6. Material:  Choose between bulk composition, whole rock/rock, glass/groundmass, or glass/inclusion

Data Output

You can view data several ways.  To change output option hit the 'back' button on your browser and select another output.

  1. Data Access - Download data in and HTML table, Text file, or XLS Spreadsheet. Options allow you to choose which chemical items you want displayed.
  2. Metadata - Choose to view a reference list or  a quickly rendered HTML table of samples. Output columns are pre-determined to commonly displayed output.
  3. Visualization Tools Choose to explore data in various formats. including TAS Diagrams, animation (for samples with age data), Harker diagrams, XYZ plots, dynamic and static maps, or Google Earth kml output.  For all options except the the static map and Google earth output, you can activate data points by scrolling down and clicking "Datapoints link to individual sample data?" followed by clicking the "Plot" button.  This allows you to view the samples metadata as it appears in its native database".  See below for more details on visualization tools. 
  • TAS and Harker Diagram Buttons:  Click on these buttons to view sample data plotted on a Total Alkali vs. Silica (TAS) diagram subdivided with the classification of Streckeisen et al. (Le Maitre, ed., 2002) or to view (Harker) plots of the compositional variation of Major Oxides vs. Silica.  You may modify the size, number of plots, and symbols displayed by using tools at the bottom of the Harker diagram page. 
  • Static and Dynamic Maps - To view samples on a map click on Static Map. Use the Dynamic map if you would like to click on a location and to view a sample information page. However, the dynamic map works best with queries of than 100 samples.
  • Plotting Tools -  Create X-Y-Z plots of elements or ratios from your queried data. Explore multiple design options!
  • Google Earth - Outputs a kml file viewable in Google Earth.  Sample locations link to the native databases and are color-coded by database of origin.

Citation Search

You may view how many times data associated with a specific author or publication have been downloaded by unique IP addresses by clicking on the Citation Search left-hand menu item. Simply enter reference information to obtain the number of downloads. The details button next to each reference provides additional information on the number of downloads per IP address and dates when the downloads occurred.


Query the database by exploring predefined parameters or create your own!  Simply register by scrolling down the Glossary menu on the left hand side of the screen.