Section 1: Wireline Logging Measurements of Subsurface Geology
Conrad and Marcel Schlumberger were French geophysicists from Alsace, who originally worked with surface electrical prospecting techniques in the search for ore bodies and petroleum. In 1927, as a result of a conversation with the manager of a Franco-Belgian drilling company, Conrad arranged for his son-in-law, Henri Doll to attempt the first experimental resistivity survey in a well.
In the Pechelbronn oilfield in Alsace, the top of the Hydrobiae marls was used as a stratigraphic marker, but was sometimes missed or misidentified in drilling. Consequently, the problem the resistivity survey would attempt to solve was whether the technique could be an effective means to recognize subsurface formations for use in correlation and mapping.
Doll put together a four-electrode (lateral) resistivity device and drove out to the well Diefenbach 2905, Tower 7, together with Scheibli and Jost on September 5, 1927. There, they linked the sonde weighted with lead to three conductive cables spliced together with insulating tape, loaded it onto a hand-operated winch, and attached it to batteries and a potentiometer. The first run was to 140 meters and took 15 hours largely because of interruptions caused by breaks in the cable. A new and longer cable was brought in by taxi to allow them to reach the full well depth of 600 meters. Resistivity readings were taken at one-meter intervals in a slow process that gradually speeded up as they became more practiced.
Doll took the logging data back to Paris and plotted the resistivity readings as a function