Recent and Key White Papers & Videos

“It’s the Rock Fabric, Stupid”

A deep dive into the criticality of rock fabric in stimulation and production of Unconventionals

Rock fabric is the generic term we use to describe the geomechanical heterogeneity in a rock formation due to: structural features like faults, natural fractures, bedding planes and variable geology. In this report, we explore the, often overlooked, role of rock fabric in hydraulic fracture propagation, drainage volume and, ultimately, production….


“Stress Shadows Explained”

Stress Shadows, the change in in-situ stresses induced by hydraulic fractures, can play a major role in stimulation success, frac hits and casing deformations

Stress Shadows is the colloquial term used to refer to the changes in in-situ stresses – both normal and shear – due to the deformations imposed by a hydraulic fracture. Here we explore why Stress Shadows form, what happens when Stress Shadows from multiple hydraulic fractures interact, and possible influences on operations…


“HF in Unconventionals: A New Geomechanics Paradigm”

The conventional hydraulic fracturing paradigm assumes homogeneity within the rock mass. This simply does not hold for Unconventionals, where rock fabric can dominate frac propagation and success

Traditional, “conventional” hydraulic fracture design assumes lateral homogeneity in stress, pressure, and rock mechanical properties such as fracture toughness, Biot’s coefficient and rock strength. This is why a typical frac model only models a single frac wing – the homogeneity of the rock makes the 2nd wing symmetric with the first. This clearly does not hold for Unconventional developments….


Why 100-mesh Proppant (and finer !): What’s the Goal?”

20/40 proppant used to be the go-to proppant size in almost all applications. What’s changed? Why the industry-wide shift to the small proppants? What does this mean for drainage volume, production and ultimate production

100-mesh proppant (and finer) simply do not have much crush resistance. So why the rush to smaller proppants? Does Fcd not matter anymore? In response to renewed fears about gel damage in the proppant pack, a major industry switch towards reduced gel loadings occurred – with a commensurate drop in fluid viscosity. At lower viscosities, our frac fluids simply did not carry proppant….


“Fracture-Driven Interactions: A Geomechanics Perspective”

“Frac hits” or more generically “Fracture-Driven Interactions” (FDI’s) are becoming more and more common. What are the geomechanics drivers in Unconventionals?

The petroleum industry has made great strides towards understanding the influence of rock fabric and geomechanics on the behavior of multi-cluster, multi-stage hydraulic fracturing along long horizontal laterals in fractured and near-fractured formations. Nonetheless, the bulk of what are now often called fracture-driven interactions (FDI’s) are related to some form of unexpected pressure communication between offset wells during hydraulic fracturing operations….

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“Casing Deformations in Unconventionals: Geomechanics Considerations”

Casing deformations (CD’s) during oilfield operations are not new; however, CD’s appear now to be more associated with hydraulic fracturing in Unconventionals

Casing deformations have been part of the petroleum industry from its inception. The first “era” of deformations were associated with the heavy oil fields on Lake Maracaibo in the 1920’s and 30’s. In the current, fourth “era” deformations are associated with hydraulic fracturing operation in Unconventionals. Here we consider the geomechanics roots of these deformations….


In this page you will find links for documents to download.


Oilfield Geomechanics’ Services – General (PDF)

Oilfield Geomechanics Services – Hydraulic Fracturing Unconventionals (PDF)

Oilfield Geomechanics Services – General_PPT (PDF)

OilField Geomechanics LLC Cover (PDF)

OilField Geomechanics LLC Cover – Spanish  (PDF)


Fracture Injection Testing (MP4)

Casing Deformations in Unconventionals: Geomechanics Considerations (MP4)

Frac Gradient Explained (MP4)

Near-Wellbore Stresses Explained (MP4)


Geomechanics for Unconventionals Series:

Fracture-Driven Interactions – A Geomechanics Perspective, Part II (PDF)

Fracture-Driven Interactions – A Geomechanics Perspective, Part I (PDF)

Hydraulic Fracturing in Unconventionals: The Necessity of a New Geomechanics Paradigm (PDF)

Geomechanics – A Simple Definition (PDF)

Geomechanics for Unconventionals (PDF)

Hydraulic Fracturing: Of Magic and Engineering (PDF)

The Complexity Paradigm (PDF)

Stress Shadows Explained (PDF)

Evaluation of Stress Shadows (PDF)

Why 100 Mesh? (PDF)

Why 100 Mesh Abstract (PDF)

Why 100 Mesh Presentation (PDF)

The Geomechanics of Zipper Fracs (PDF)

Who Redefined Frac Gradient…And Why? (PDF)

URTeC 2018, “Completions Engineer for a Day: How Geology and Geomechanics Impacts Completions Design in Unconventionals” (PDF)

On The Geomechanics of Refracturing (PDF)

ReFrac Considerations (PDF)

Geomechanics and Sand Volume Per Length of Lateral (PDF)

It’s the Rock Fabric, Stupid! (PDF)

Other Great Articles:

Geomechanics of Induced Seismicity (PDF)

On the Proper…And Not So Proper…Laboratory Testing for Young’s Modulus and Poisson’s Ratio (PDF)

Dr. Neal Nagel 2016-17 SPE Distinguished Lecturer Abstract and Bio (PDF)