Don Clarke

Senior Petrophysical Advisor

Leatherhead Technology Group

March 2019

What does a career in petrophysics look like?

LPS Petrophysics 101

Petrophysics

from the Greek πέτρα, petra, "rock“ and φύσις, physis, "nature") it is the study of physical and chemical rock properties and their interactions with fluids.(https://en.wikipedia.org/wiki/Petrophysics)

Accurate determination of petrophysical properties for both the reservoir (rock) and its fluid contents is the basis of relevant formation evaluation. Schlumberger website

Petrophysics is the study of the properties (physical, electrical, and mechanical) and the rock/fluid interactions of petroleum systems.SPE website

Petrophysics is the study of rock properties and their interactions with fluids (gases, liquid hydrocarbons, and aqueous solutions). The geologic material forming a reservoir for the accumulation of hydrocarbons in the subsurface must contain a three-dimensional network of interconnected pores in order to store the fluids and allow for their movement within the reservoir.Petrophysics by Djbbar Tiab and Erle C. Donaldson

What is Petrophysics?

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What do petrophysicists do?

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What does the rock

look like?

Where is the fluid stored

and how does it flow

through the rock?

Petrophysicist

Exploration Geologist

• Regional Scale

• Vertical WellsProduction / Development Geologist

• Field Scale

• LWD / High Angle Wells

Geophysicist

• Well->Seismic

Drilling Engineer

• Rock Mechanics

• Open-holeCompletions Engineer

• Cased-hole

• Isolation

• Flow assurance

Geological Modeller

• Field Scale

• Upscaled

• Static

Reservoir Engineer

• Field & Well

• Time is a factor

• Dynamic

Commercial / Business

• Review of reports etc

• Evaluating acquisitions

Who do petrophysicists work with?

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Marriage of Geology & Physics

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Spans Historical and Modern Technologies

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Old “Electrical Coring” Job

The first resistivity log on September 5th, 1927.

Schlumberger Rt Scanner triaxial

induction service.

Old single detector

neutron tool ~1941.

The RockView service

from Baker Hughes, a

GE Company

• People come into petrophysics from many different technical

backgrounds.

• Petroleum engineers and other engineering backgrounds (chemical,

electrical or mechanical)

• Scientists (geology, chemistry, physics, …)

• I have worked with astrophysicists, nuclear physicists, applied

mathematicians and even a ceramic engineer (i.e. bio-medical).

• Operations focused

• Field Studies focused

• Equity and Reserves

• Exploration vs Production

• Ultra-specialist (i.e. resistivity tool modelling or acoustics)

• Jack of all trades (i.e. a bit of everything)

Petrophysicist: there is no typical career!

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• I have removed the personal history slides due to privacy.

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The Future of Petrophysics…

…The March of Technology

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Witnessing Logging Jobs

On the rig

In the office

At home

Through a phone app

Computers

DEC Vax Mainframes

Sun Workstations

PC Workstations

PC Laptops & Tablets

Wireline Tools

Nuclear Magnetic Resonance

Borehole Imaging

Downhole Fluid Analysis

Rotary Sidewall Cores

Dipole Sonic Measurements

Elemental Spectroscopy

LWD Tools

MWD

Gamma Ray + Resistivity

Triple Combo

Quad Combo

Azimuthal Measurements (Images)

Seismic While Drilling

Pressure and Samples While Drilling

Deep Reading Azimuthal Mapping

(5m to 35m)

Well Datasets

Hardcopy (paper and printouts)

<1 MB (a floppy disk)

<100 MB (a couple of 9-track tapes)

~1 GB (a single cartridge tape)

Multi gigabyte to terabyte datasets

…

As computing power has evolved, geological, geophysical and reservoir modelling have also advanced, requiring ever increasing input from the petrophysicist. The role still involves

the traditional operational data planning and gathering as well as providing cleaned up log and core data, quick look analysis and computation of basic rock properties (Vsh, Por and

Sw). However increasingly petrophysicists have become more involved in advanced data clean up’s, use of AI and neural networks for advanced rock property prediction, analyses

for rock physics including fluid substitution for seismic processing, saturation height modelling, and cased hole log evaluation.

Petrophysics today extends over the entire life cycle of a field from exploration to field abandonment.

Having said this, the role sometimes still suffers from the old preconceived notion that petrophysicists do the data acquisition and after that are not required. It is something I have

spent much of my career challenging and persuading. To help explain the multitude of tasks an experienced petrophysicist may be expected to cover I have split out the different

roles they may find them selves involved in. Some of the larger operators employ the full range including the specialisations while others prefer to outsource these. In smaller nimbler

operators some of the roles are also combined and a very experienced senior petrophysicist would be expected to cover the majority of these sub roles.

…

• Operations Petrophysicist

• Exploration Petrophysicist

• Appraisal Petrophysicist

• Development Petrophysicist

• Mature Field Petrophysicist

• Abandonment Petrophysicist

• Quantitive Interpretation and

Rock Physics Petrophysicist

• Cased Hole Petrophysicist

• Coring and Core Analysis Specialist

• Image Processing Specialist

The evolving role of the petrophysicist

10https://www.linkedin.com/pulse/evolving-role-petrophysicist-andrew-winter

From a LinkedIn post by Andrew Winter

Courtesy of Wikicommons

• I have approximately +20 years in this industry and I have no plans to

change career

• Do something that you love to do

• Follow your interests/passions but find the sweet spot that has

commercial value

• Keep learning… do not stand still… technologies advance is rapid!

• Learn to write good code (i.e. Python 3)

• Find a mentor or two and be a mentor to others

Finally, Some Career Advice…

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