Chroni Repository


Chroni is a mobile application that presents archived data downloaded from the Geochron database in a customizable format for use by geologists in the field. Currently, the Chroni application only works with Android devices, but an IOS application is in development. The project is led and maintained by CIRDLES, an undergraduate research lab at the College of Charleston in Charleston, South Carolina.

Concept of Operations

The purpose of Chroni is to allow people to archive data, while collecting data in the field. With CHRONI, users do not need to remain stationary.

Information for use of Documentation

The documentation below is essentially a set of step by step instructions on how to operate the software. For auditory and visual learners, youtube video tutorials will be included among the written instructions, so there will be a video demonstration of CHRONI operations from an android phone ( or tablet).

Policies that affect the System

This material is based upon work supported by the National Science Foundation under Grant Numbers 0930223 and 1443037. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.


The current documentation applies to Chroni version 1.0.1

When on your android tablet, Chroni will be stored in your applications menu. Click on the Chroni icon to open the application and you will arrive at the Home Screen.


  1. Click the open button on the Chroni Home screen and you will arrive at the Aliquot screen. On the Aliquot screen, Current Report Settings will be listed as Default Report Settings.
  2. Click the plus sign next to the Saved Aliquot file input form and choose an Aliquot saved on your device. After you do so, the file name for the aliquot file will appear in the input form.
  3. Click the open button in order to view the Aliquot table. At the top of the table, there are two detail buttons Report Settings and the current name of the Aliquot.
  4. When you click on the Concordia button, you will be redirected to a web browser that will open up a graphical image of the current sample.
  5. When you click on the “Probability Density button, you will also be taken to a web browser that will open up a graphical image of the current sample.
  6. The table itself contains the following information categories:



    -Isotopic Ratios

    You will be able to scroll vertcally and horizontally to observe the information on the given table. In order to return to the Aliquot screen, click the back button.

  7. The GeoChron IGSN file input form requires a GeoChron IGSN, which can be found on the SESAR website after you register your samples.


  1. From the home screen, click the History button to arrive at the History screen.
  2. A table will show the recent Aliquots you have opened within the Chroni application with the following details:

    -Last Opened


    -Report Settings

  3. There are Open buttons to the right of the table, which will allow you to open past aliquots.
  4. The Home button on the bottom of the page will take you back to the Chroni homescreen.

Report Settings

  1. From the home screen, click the Report Settings button to arrive at the Report Settings screen.
  2. The Current Settings will be “Default Report Settings.”
  3. Click the plus sign next to the Device file input form to choose a report setting. Then, click the Open button to be taken to the Aliquot table and a notification will say “Your current table info has been stored!”
  4. Click the Cancel button in order to return to Chroni’s home screen.


  1. From the home screen, click the Credentials button to arrive at the Credentials screen.
  2. There are input forms that will request your Username and password associated with your GeoPass account. Enter theses in their respective forms and click validate to log in from your tablet.
  3. You can also click the Home button in order to return to the Home Screen or the Reset button to clear both input fields and get a notification saying “Credentials erased.”


Aliquot - phsyical pieces of a sample whose dates you wish to interpret seperately.

Concordia - clicking this option will open up a web browser and show you an Uncertainty Ellipse Plot.

Fraction - a paired U+Pb analysis

Isotopic Ratios - refers to isotopes whose abundance is affected by processes in nature

Probability Density (Function) - the density of a continuous random variable. This describes the likelihood for the random variable to take on a given value. Clicking this option will open up a web browser and show you a Bar Graph.