Formation Evaluation for Geology Dummies

Example of data used for formation evaluation

We've come full circle to end our week of DotD nominations from the fertile fields of WiseGEEK.com, and to do so we decided to "Dance with the one that brung us," as an old boss used to say. A couple of months ago we ran across a post at the site (by Paul Reed) that made it plain as the nose on your face that the author knew zilch about the oil business. We're closing out the week with a post by another WiseGEEKian, Larry Ray Palmer, who knows pretty much the same about "What is a Formation Evaluation?" (now, for some unknown reason, at AboutMechanics.com).

The staff petroleum geologist scratched his head and muttered, "I've never heard of 'A formation evaluation,' but..." and referred anyone interested to the definition of the process at the oil industry's go-to glossary (compliments of Schlumberger). The definition there is fairly restricted, describing a process consisting mainly of evaluation of wireline logs. That differs from Palmer's take (for which we have no reference), which is... rather more general:

"Using geological assessments, exploratory drilling, coring, and other procedures, petroleum drilling companies are able to assess the value of a bore hole for production."

We call BS on that. First, drilling companies are not the same as exploration companies. Second, you don't evaluate the entire bore hole, you evaluate potentially productive intervals. Third, most of  an actual formation evaluation comprises what Larry Ray apparently thinks are the "other procedures."

According to Palmer, formation evaluation entails the following:

• "...geological assessment... Trained geologists look for recognizable formations that are known to yield [fossil fuel] resources.": No, Larry, that's part of prospect generation, not formation evaluation. Not to mention that geologists sure wish all you had to do was "look for recognizable formations"!

• "Exploratory drilling of bore holes is used to collect soil samples, called cores, and data about the sub-surface formations that may yield petroleum.": You blithering idiot, exploration wells don't explore "soil"!
• "Coring is a process of extracting samples of earth from the bore hole. Long, hollow tubes are placed in the drilling rig and then forced into the formation, thus creating a core of earth.": No, Larry, coring is not a process of forcing "Long, hollow tubes... into the formation"! It's hard rock, not dirt, not to mention that exploration wells are thousands of feet deep!
• "Mud logging tracks the mud and drilling fluid that is brought up by the drilling rig.": Idiot, the mud IS the drilling fluid!
• "Small electrical leads are attached to the drilling equipment and lowered into the bore hole..." Dear Lord, is everyone this ignorant?
• "Nuclear porosity testing is accomplished by emitting small amounts of radiation and then tracking its progress into the surrounding geological formations.": "Tracking its progress"? Is this idiot kidding?

Nope, Palmer's not kidding – he's merely completely ignorant of the answer to the question, "What is formation evaluation?" His answer conflates formation evaluation with the entirety of exploration, only briefly brushing up against the real definition of the process (see SLB above). Is it any wonder our petroleum geologist wanted to personally hand a Dumbass of the Day award to Larry Ray?

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