Induction logging sonde with metallic support

Patent · Mon Mar 16 23:00:00 EST 1987

OSTI ID:6681458

Barber, T D; Chandler, R N; Hunka, J F

This patent describes an induction logging sonde adapted for displacement in a fluidfilled borehole for investigating the formations traversed by the borehole, comprising: at least one transmitting solenoid coil transmitting at a frequency between about 10-400 KHz for generating an electromagnetic field substantially free from dielectric effects, which field induces currents in the formation, at least one receiving solenoid coil axially spaced from the transmitting coil for producing in response to the field induced by these currents a signal indicative of the conductivity of the formation, an elongate support having at least one first longitudinal portion mounting the coils in coaxial and spaced relationship thereto and second longitudinal portions on both sides of the first portion, the support being made of electrically conductive metal. At least the first portion has a substantially continuous outer surface to favor the flow of eddy currents resulting from the electromagnetic field circularly around the surface, the second portions being exposed to the pressure of the borehole fluid.

• Assignee: Schlumberger Technology Corp., Houston, TX
• Patent Number(s): US 4651101
• OSTI ID: 6681458
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
BOREHOLES
CAVITIES
CURRENTS
DIELECTRIC PROPERTIES
EDDY CURRENTS
ELECTRIC COILS
ELECTRIC CURRENTS
ELECTRIC LOGGING
ELECTRIC PROBES
ELECTRICAL EQUIPMENT
ELECTRICAL PROPERTIES
ELECTROMAGNETIC FIELDS
EQUIPMENT
FLUIDS
FREQUENCY RANGE
GEOLOGIC DEPOSITS
INDUCTION LOGGING
KHZ RANGE
KHZ RANGE 01-100
KHZ RANGE 100-1000
MECHANICAL STRUCTURES
MINERAL RESOURCES
PETROLEUM DEPOSITS
PHYSICAL PROPERTIES
PRESSURE EFFECTS
PROBES
RESERVOIR FLUIDS
RESERVOIR PRESSURE
RESOURCES
SIGNALS
SOLENOIDS
SPACE DEPENDENCE
SUPPORTS
WELL LOGGING
WELL LOGGING EQUIPMENT