Shell Oil Comapny

Frederick H Rambow

Jeremiah Glen Pearce

Dennis Edward Dria

Rocco DiFoggio

David Ralph Stewart

Edward A Clerke

A method for identifying fluid migration or inflow associated with a wellbore tubular, comprises measuring strain of the wellbore tubular with a system comprising at least one string of interconnected sensors that is arranged such that the sensors are distributed along a length and the circumference of the wellbore tubular; establishing a baseline that is a function of steady state strain measurements within a first time period; and identifying fluid migration or inflow where strain measurements substantially deviate from the baseline within a second time period.

Systems and methods for monitoring a well

Systems and methods for monitoring a well are configured to identify or analyze various issues affecting the well including corrosion, cement quality, inflow, and fluid migration.

Use of fiber optics to monitor cement quality

A focused acoustic transducer for use with a borehole televiewer wherein the transducer is provided with a concaved surface designed to focus the acoustic energy and reduce the energy present in the side lobes of the near field.

Transducer system for use with borehole televiewer logging tool

A method and apparatus for detecting fluid flow behind an acoustically reflective structure using pulse echo techniques which do not depend upon measurement of a Doppler effect. A transducer is provided for generating a high frequency beam of acoustical energy in the form of pulses. The transducer is placed proximate, preferably adjacent, the reflective structure such that the acoustic beam is directed toward such structure. A transducer is also provided for detecting the acoustic reflections of the pulses, proximate the position from which the pulses originated, and generating corresponding electrical signals. An electric circuit is provided for subtracting a pair of acoustic reflection signals separated by a short interval of time to produce a difference signal from which the presence or absence of fluid flow behind the acoustically reflective surface can be determined. In the preferred embodiment, a preselected number of the difference signals are 'stacked' by adding the absolute values of such signals to produce a 'stacked' signal trace which is more susceptible to evaluation, especially for determination of relative flow velocities.

Pulse echo technique for detecting fluid flow

A process for measuring the thickness of the cement surrounding a casing in a borehole wherein a radioactive tracer is mixed with the cement and the response is monitored to determine the cement thickness. An alternate method is the mixing of a material with the cement that can be activated by a neutron source with the resulting activity being measured to determine the cement thickness.

Radioactive tracer cement thickness measurement

An acoustic logging system for detecting anomalies in formations surrounding a borehole. The system can be used for evaluating the formation for fractures or the bond between a well casing and the cement used to seal the space between the casing and the formation. The system utilizes at least one rotating acoustical transmitter/receiver and at least one receiver vertically spaced from the rotating transducer. The signals from both receivers are analyzed to detect the presence of anomalies, such as fractures or voids in a cement bond.

Borehole televiewer for fracture detection and cement evaluation

Amplifier gain is time ramped to increase amplification of the signal with increasing mud transit time and attenuation. Amplitude, ramp slope, and ramp onset time are independently controllable from the surface.

Time ramped gain for borehole televiewer

A method for determining the true dip and azimuth of bedding planes in a formation penetrated by a borehole using borehole televiewer measurements. The method corrects for borehole deviation and for inclination of the earth's magnetic field.

Method of using a borehole televiewer dipmeter for determining true dip

A borehole televiewer circuit for compensating for out-of-roundness of a borehole. The circuit comprises an automatic gain control circuit having time constants that allow detection of borehole anomalies while having a fast enough rise time to adjust for the effects of out-of-roundness.

AGC circuit for televiewer

A display system for use with a well logging tool of the type that scans a borehole wall by rotating an acoustical transducer while emitting and receiving acoustic energy. The received acoustic or information signals are received and recorded for later use. In addition, both the amplitude and time-of-flight of the information signals are digitized and passed to a computer that controls a television display and cathode ray tube. The amplitude is displayed on the television screen while the time-of-flight is displayed on the cathode ray tube as a caliper log.

Growing community of inventors

Houston, TX, United States of America

Frederick H Rambow