Density Log Porosity

Calculating density log porosity

This program calculates porosity from density logs, corrected for shale if desired.

The density log is one of the best devices in shaley sands. The densities of shale and sandstone are usually close, and the magnitude of the correction is less than for sonic or neutron logs. The density log is also a good proxy for Total Organic Carbon in shales.


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.