The Super Petrophysics Blog

Simple shortcuts to day-to-day petrophysics.

How to Acquire Good Cased Hole Logs: The Checklist

(Source: Petroleum Engineering Handbook Volume V) Here is the checklist of data acquisition for cased hole logs. Ask why do you need the data: Baseline? Measure changes in the well after completion like high water cut, corrosions, high GOR, saturation change? Ask how do you...

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How to easily read a well log in 5 minutes or less using these Six Ko Ko​ Rules

Petrophysicists look at the well log patterns, recognize the trends, and then turn those patterns into reservoir knowledge. Well logs can tell us many stories about our reservoir. Each colorful line, each curve deflection and each curve type create the story of our reservoir. Each reservoir...

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You might have a CBM reservoir if you see this from your well log

How do you spot a coal layer from your well logs? Just remember this: CBM consisits of coal layers. So technically, you are looking for coal layers/beds. First, you can see coal cuttings from the shale shakers or from the mudlogs. You will notice an increase in gas readings over a CBM...

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Try This When You Can't Take Fluid Samples in Your Open Hole.

You want to obtain a subsurface fluid samples from using a wireline formation tester (WFT) tool like RCI and MDT from your well for PVT analysis, reservoir studies, and reserve booking. The bad news is you couldn’t do it because of the operational constraints like: 1. Wellbore...

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Six Times When Geosteering Might Help

Delivering a healthy well that's producible for the next 20 years is always better than skimping a few thousand dollars merely drilling a hole today. Geo-steering is one of the techniques to achieve that. Geo-steering helps to adjust our wellbore position inside the target reservoirs based on...

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High water saturation, but zero water production in your carbonate reservoir? Find out what to do about it.

Sometimes, carbonate reservoirs just don’t make sense especially when you are dealing with low resistivity pay (LRP). (image: sandatlas.com) For an LRP reservoir (virgin with no prior production), you’d notice sections or layers with lower resistivity readings in the same oil bearing...

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Five Things You Thought Were True About Well Logs.

I took a semester of ‘Well Logging and Formation Evaluation’ class back in college. I had no appreciation of well logs, but I liked the class nonetheless. I used to think that well logs were so awesome that they could tell us everything. Boy, I was dead...

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This Butterfly Effect Has Nothing To Do With Hollywood

"The Butterfly Effect" is not all Hollywood. In our oil and gas, our "Butterfly Effect" has nothing to do with Ashton Kutcher. It's about is detecting gas based on signatures of the density and neutron logs. When you plot density log and neutron log on a limestone compatible scale on the same...

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Why The Ko Ko Rules Won't Work In Shale Oil

The quick look method (i.e. The Ko Ko Rules) doesn't work in shale oil reservoir. Because every tight oil reservoir is different, there's no one-size fits all solution. Complex lithology (like mixture of quartz, clay, dolomite, calcite) and complex geology (thin low porosity sequence that's...

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How to measure fluid movements inside borehole - The super guide to production Logs

How does the formation respond to production or injection? How do we measure the production profile and saturation change in our wellbore? To establish production profile, we use production logging tools (PLT). For vertical well or single phase flow, we use a PLT tool string with single inline...

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