Documentation written by: Susan Kaspari
Funding: Climate Change Institute, University of Maine Download pdf version
The ice core dating software is a program designed to create a depth-age scale from ice core glaciochemical records.
To run the program, the glaciochemical data needs to be saved in a comma delimited file (.csv), tab seperated file or space seperated files(text files) with the columns in the following order with the following headings:
| tube | top | bottom | length | Na | NH4 | K | Mg | Ca | Cl | NO3 | SO4 |
Tube = tube number
Top=top depth (m)
Bottom = bottom depth (m) Length=sample length (i.e., top depth-bottom depth)
Na etc. = the concentrations for measured time series.
To start the program, open the software NewIceCoreDating.jar From the Start Menu, click 'Start A New Dating Session' The program will prompt you to open your data file (go to the ice core dating file where the file was stored). The program will read "Your file contains X zeros. File is in valid format, you may proceed. Click OK. Under Main Menu, click the elements that you want to plot. Enter the top year of the ice core in the box (if you know the top of the core is 2000, enter 2000). Choose plotting method. Click OK The program will ask to confirm that the top year is XXX.
Before beginning to date the core, set the x and y axis to appropriate limits to maximize the detail necessary for making annual picks.
The Y axis is adjustable for each element. In the box below the graphs, select the element for which you want to adjust the scale. Enter the minimum and maximum Y values, and click `Set Y Axis limits'. Log values
To zoom in on a section: Click on the box next to 'Zoom'. Put the mouse over the graph- a blue vertical line will appear. Click (and hold), and drag over the section of the graph that you want to zoom in on. The program will highlight the section of graph that you are zooming in on- when you've highlighted the desired region release the mouse and the program will adjust the x axis limits. To zoom out on the X axis: To zoom out a small amount, right click. Select 'Zoom out' then 'horizontal axis'. The program will increase the X axis range. To reset the X axis to cover the whole range, right click. Select 'Auto range' then 'horizontal axis'. The program will increase the X axis to cover the whole dataset.
Once the axis limits have been set, select 'Start Recording'. Align the vertical line over the graph to the location where you want to record a year. Click the mouse. A line will appear with the year recorded at the top. Continue this process over the core. The program will automatically count down from the top year of the core.
Note- if you reset the Yaxis limits after recording years, the year labels may not be visible. One way to work around this is to delete a year and then re-record it. The year labels should reappear.
If a year is recorded that you want removed, click on 'Delete'. Align the mouse over the vertical line of the unwanted year, and click. The year will be deleted. To resume dating the core, click on 'Recording'.
To move to another section of core, click 'Pan'. This feature enables you to pan up or down the core to work on a new section. For example, to pan down the core, click on 'Pan', click on the right side of the graph and drag towards the left side of the graph. The opposite enables viewing of upper sections of core.
To save your dating, click 'Generate Report'. The program will display 'Report generated successfully. Click on view report to display it'. Reports can be generated at any point during the dating process. YOU MUST GENERATE A REPORT TO SAVE YOUR WORK.
To view the report from the ice core dating software, click 'View Report'. A window will display the depth for each year. The report can also be viewed from other programs (Excel, etc.). The program automatically stores the report in the ice core dating folder under 'Reports'.
After a report has been generated, you can continue working on the core at a later time. From the Start Menu, click 'Continue An Existing Dating Session'. Browse to the folder containing the Core data file (the .csv file) and select the appropriate file. The software loads the data along with your previously determined annual picks.
The ice core dating window can be printed or saved by right clicking, and selecting either 'print' or 'save'.
The ice core dating window can be printed or saved by right clicking, and selecting either 'print' or 'save'.