Acoustic velocity measurements in materials using a regenerative method

Patent · Mon Jan 20 23:00:00 EST 1986

OSTI ID:5946022

Laine, E F

This patent describes a method for measuring stress in the material of a volume of earth between first and second boreholes. This step includes the following: generating acoustic energy in the form of sinusoidal shear waves in the first borehole by means of a generator that converts electrical energy to acoustic energy. This acoustic energy is directed toward the second borehole; receiving the acoustic energy in the second borehole and converting the received energy into electrical signals; amplifying the electrical signals for transmission to the generator; the steps of generating, receiving the amplifying are performed inclusively in a closed loop that also includes the material; the amplification having sufficient regenerative gain to produce sustained oscillations in the closed loop which indicate the stress of the material of the volume of earth through which the acoustic energy is being transmitted; the generating, receiving and amplifying is done in the closed loop, the inherent noise in the closed loop providing initial signals to build sustained oscillations.

• Assignee: Dept. of Energy
• Patent Number(s): US 4566084
• OSTI ID: 5946022
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
58 GEOSCIENCES
580203 -- Geophysics-- Geophysical Survey Methods-- (1980-1989)
ACOUSTIC MEASUREMENTS
AMPLIFICATION
BOREHOLES
CAVITIES
ELECTRONIC EQUIPMENT
EQUIPMENT
FUNCTION GENERATORS
GAIN
GEOLOGIC DEPOSITS
GEOPHYSICAL SURVEYS
MINERAL RESOURCES
NATURAL GAS DEPOSITS
OSCILLATIONS
PETROLEUM DEPOSITS
PHASE VELOCITY
PULSE GENERATORS
REGENERATION
RESOURCES
SEISMIC S WAVES
SEISMIC SURVEYS
SEISMIC WAVES
SIGNAL-TO-NOISE RATIO
SOUND WAVES
STRESS ANALYSIS
SURVEYS
VELOCITY