Latest Version: 4.2_1, May 2004.
Simplified Data Input. Added Kono (1980) Paleomag Latitude Calculator Toolbox.

(Source Code in Visual Basic 6.0 Now Available. Also available at the Download Page)

This paper describes a Windows-based paleomagnetic analysis program integrates on-screen visualization and analysis of paleomagnetic data and printing graphic outputs. The program is easy to understand and use with its graphic user interface. It accepts fixed length or delimited data files, each of which can contain up to 500 samples with a variable number of demagnetization steps (up to 50). The integrated toolboxes accept keyboard or copy-and-paste data input, and allow the user to calculate paleolatitudes, convert between spherical and Cartesian coordinates, and perform many functions of the main program.

The main program converts an ASCII data file into a specially formatted file (*.mag) for random read/write access. After conversion, the *.mag file is automatically opened, and a list of sample is displayed in a small window. When a sample on the list is clicked, the associated demagnetization data are displayed in a nearby window. The user can visualize the data using the Zijderveld (/modify Zijderveld) projection and the stereographic (/Lambert equal-area) projection simultaneously or individually. The data visualized can be in either geographic or tilt-corrected coordinates, from all or certain demagnetization steps of a sample, or from a single demagnetization step of all samples. Characteristic directions of each sample are derived from a three-dimensional least-squares fit of selected demagnetization steps by principal component analysis (PCA). Mean directions from "Fisher" analysis are computed from click-selected samples using a designated demagnetization step or the characteristic directions. These mean directions are automatically computed for each polarity by a routine that compensates for pervasive overprint directions, and that can also utilize subjective weighting of sample directions. The graphic outputs can be printed on paper or screen-captured into graphic software, and the analytical results can be copied and pasted into word-processing programs.

(From: Zhang, C. and J. G. Ogg, 2003: "An integrated paleomagnetic analysis program for stratigraphy labs and research projects." Computers & Geosciences 29: 613-625.)

Improvements over version 4.0: Save the user a lot of hassle in data input

  1. A new tab-delimited data file format is added (*.nta). No need to indicate where the data of a sample begins and ends. The program automatically recognized a sample by the same sample name (two parts).
  2. When editting large data files, it is easy to make mistakes. If an error occurs during data conversion, the program indicates not only the error type, but also the line number where the error occurs. The user can then use a text editor such as Notepad to open the data file, go to the line indicated by the program, and correct the error. The error is usually on that line or the previous line. Save the data file, then go back to Paleomagnetic Analysis Program, and convert the file again. If another error occurs, repeat this procedure. In this whole process, you do NOT need to quit the Paleomagnetic Analysis Program.
  3. The sample header of the data file is simplified to contain only the necessary information: Sample name (two parts separated by a tab), and the meter level of the sample in the section.
  4. Kono (1980) paleomagnetic latitude calculation routine added as a toolbox in May 2004.

This program is free of charge, and can be downloaded from the following download page (latest version 4.2_1) or from the server of Computers & Geosciences at http://www.iamg.org/CGEditor/cg2003.htm (Version 4.0 as published), together with user's manual and materials for teaching paleomagnetism to undergraduates in stratigraphy classes.

If you have installed a previous version of this program, you can normally update to the latest version by replacing the paleomag.exe file (usually in the folder C:\Program Files\PaleomagneticAnalysis) with this one. If this does not work, download the latest version, unzip it, and run the setup.exe program again.

Sample screen captures:


Last updated: April 6, 2005 by Chunfu Zhang.
If you have any comments or need any help, please contact the webmaster or Dr. James G. Ogg.