Overview

For this month’s issue of featured well-stimulation papers, the ongoing work in acidizing earns my recognition as the most enlightening and yet overdue progress. Although the papers spotlighted in this issue are strong presentations on diverse subjects, I was most surprised by the volume of engaging papers focusing on acids and fracture acidizing. There are great papers in my list with information on horizontal wells, gravel packing, and viscoelastic fluids; however, each of these technologies is young compared to acidizing reservoir rock.

In one of the additional-reading selections, “Fracture Acidizing: History, Present State, and Future,” we learn that acidizing carbonates dates back to 1895. Therefore, the use of acids to increase production is more than a century old. With many of the modern acidizing theories developed around 1972 by Neirode and others, it is still a 35-year-old technology that needs a fresh look with modern methods. Whether we are studying etching behavior to forecast conductivity or predicting long-term reductions in performance caused by creep, we still have a lot to learn about this venerable practice.

Therefore, the question becomes: “How can acidizing oil wells be more than 100 years old, yet we just now are beginning to unravel these fundamental concepts?” The world produces approximately 85 million BOPD, and assuming just USD 50/B, we generate more than USD 1.5 trillion/yr in world oil revenue. Whatever the historical disconnect has been between oil revenues and funding oil science, I am pleased to recommend these compelling technical papers on subjects vital to our industry, including the common practice of pumping acid into a formation to increase production.

A Small-Scale Fracture-Conductivity Study

Rock-Mechanics Considerations in Fracturing a Carbonate Formation

A New Method for Acid Stimulation Without Increasing Water Production

Horizontal-Openhole Gravel-Packing Operations in the Campos Basin

Charles Hager, SPE, is a senior consultant with NSI Technologies. For the last 17 years, he has focused on applying and integrating the sciences of hydraulic-fracturing analysis and modeling, pressure-transient analysis, and reservoir simulation. Hager earned a BS degree in petroleum engineering from the University of Alabama, and he serves on the JPT Editorial Committee.

Overview

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