LogCalc: Dual Laterolog
Dual Laterolog

Dual Laterolog correction

This routine (and the program for Dual Laterolog correction) use Asquith's equations. They deliver reasonable corrections to deep resistivity and are usually close to the values you get by hand off a 'tornado' chart for typical Rxo/Rm ratios.

I find you get better values taking an Rxo reading (resistivity of the flushed zone) from a microlaterolog, in some versions called the microspherically focused log. You can correct the deep resistivity without it, by telling the program what kind of dual laterolog tool spacing (28' or 20') was used. This latter estimate is important, because microlaterologs are not always run with the dual laterolog.


Do you want to save your calculations? The input box at the very bottom of the screen records all the inputs and outputs for each calculation run. To save this information, select all the text in the box and copy it, then open a spreadsheet and paste it in as comma-separated values. Each data type will land in its own column, and each calculation run, or depth, will occupy a row. Format the spreadsheet to separate rows into different geologic formations, and you're done. Isn't that easier than writing everything down?

Don't have a spreadsheet handy? If you are working on a phone or a tablet, you can still copy the text and paste it into a note or an email.

The Recording box will reset if you press the "Help" or "Reset" buttons, or if you navigate to a different page.