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How to read an Oil & Gas Well Log Video

This 8 minute video, gives a short education on reading a RockVision Log. Although it was meant to be internal as you may tell by the production it gives an honest overview from an oil & gas expert, we hope you enjoy. Again, this video goes over of how to read a RockVision log by Halliburton. This video is based on a well in the Permian Basin, it was filmed in Midland Texas at 7s Oil and Gas HQ. Speaking is Gilligan Sewell the owner of our company. the text that follows will be a play by play of what you will learn. First is basic mapping of the log (depth oil, gas, and water). Followed by how much oil you can count on of pulling out of your well in comparison to what the log says. We then discuss a core sample and the effects of pressure and acid on that sample.

What formations are in the Permian Basin? for more info on formations please see the illustrations below:

What kinds of Oil can be pulled out of your well (regular crude of course but premium oil as well). These are the 2 samples in the video, a well actually can get many variations of oil and gases some need less processing then others.
crude and premium oil from the well

Where do you perforate, how do you tell by a log to frac and why…. for more info on Fracking Read this article (the video briefly speaks about the effects of water on oil under the ground)

Other resources and more on logs:

When you have digested that another valuable resource is the Society of Petrophysicists and Well Log Analysts. You will want to download all of the mnemonics for well logs in order to understand what you are reading.
They also sell some useful publications.

There is a logging company called Wellog that has put a free web seminar up on well log interpretation that looks informative (I have not used it):

The Society of Petroleum Engineers is another useful resource with excellent publications.
SPE publishes many books on well logging but the two introductory books I would recommend are:
“Well Logging 1- Rock properties, Borehole environment, Mud and Temperature Logging” Monograph Volume 9
“Well Logging II- Electric and Acoustic Logging” Monograph Volume 10.
There are available at:

If you have some well log interpretation software, or even if you don’t you can find what are called raster logs (image files) on the internet for many states. Louisiana has these at
Other states offer them in LAS or LIS format, which requires special software to interpret, but at Schlumberger you can download a free LAS toolbox that will allow you to read these logs: