WELLOG Pechelbronn
© 2004 – 2006
WELLOG
It began in Paris France,
1876, when Paul Schlumberger met Marguerite De Witt, granddaughter of Francois Guiznot, a famous French historian and statesman. The
father of Paul Schlumberger was Nicolas Schlumberger, the family patriarch,
entrepreneur, and inventor in the textile industry. Five sons and one daughter were born into the
Schlumberger family. Two sons, Conrad and Marcel Schlumberger, born with the
ambition to prospect and apply pure science in combination with their frugal
entrepreneurial skill moved electrical
prospecting and the science of geophysics into the 20th century.
“Crisscrossing an area in
an old, light truck”…
“Conrad would climb up
beside the driver, Marcel and an engineer (fresh out of school) would pile into
the back with the equipment, their legs dangling… One planted the pegs, another
dragged the cables, the third took the measurements….
Notebook in hand, Conrad made his observations…”
“The weaker voltages forced
him to follow the movement of the potentiometer needle with a magnifying
glass…”
“The men would return home
covered in mud, dead tired…”
“What was needed was to
replace the stakes on the surface with sondes at the
bottom of the hole so as to explore their walls.”
Note: The word ‘sondes’ refers to the cylindrical logging tools used for well
logging.
“Taking measurements in
boreholes was a logical and technical extension of surface electrical
prospecting.”
“In August, 1927 Henri Doll
settled in Pechelbronn, France.”
“My father told me to
imagine an eye, which, traveling up and down the length of a borehole, would
recognize the nature of the different strata traversed by the bore.”
“The equipment, however,
could not have been more rudimentary; roughly, it included three conductive
cables spliced together with insulating tape every five meters, a sonde weighted with lead, a winch operated by hand, storage
batteries, and a potentiometer.”
Note: the “potentiometer” was
an instrument used for measurement of “electrical potential” (voltage) similar
to an analog voltmeter.
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Henri Doll, 48, the
youngest, and the Schlumberger brothers, Conrad and Marcel, after several
failed attempts, and cable breaks, made a great leap forward in the history of
geophysics…
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“A few days later, on September
6, 1927, at an inn in Woerth, a dinner marked a
memorable date – the date of the first
electrical measurements taken in a borehole… This was the birthday of
“electrical coring”.
“The term electrical coring was adopted in 1927
by analogy with mechanical coring… the expression was replaced in 1933 by electrical logging, the term now in
use throughout the petroleum industry.”
“The term log represents a strip of paper
or film on which the measurements are recorded as curves (diagrams) in terms of
depth, as a marine log measures the distance traveled by a ship in time.”
Credits:
Quotations are from the book “The Schlumberger
Adventure” by Anne Gruner Schlumberger. Anne Gruner Schlumberger was the daughter of Conrad Schlumberger.
Marcel Schlumberger was her Uncle. Henri
Doll was her husband.
Learn more about electric
logging (E-Log) and modern
advancements in this method on this website!
