Schlumberger Technology Corporation

Alain M Dumont

Peter T Wu

Pierre Henri Campanac

Tetsuya Tanaka

Dzevat Omeragic

Harold Pfutzner

David Linton Johnson

Fernando Garcia-Osuna

Toshihiro Kinoshita

Hiroshi Nomura

Tarek M Habashy

Jacques R Tabanou

Emmanuel Legendre

Qiming Li

Hiroshi Nakajima

Hiroshi Hori

Richard Bloemenkamp

Khanh Anh Duong

Jan Stefan Morley

Philippe Salamitou

Nicolas Renoux

Libo Yang

Jeffrey A Beren

M Reza Taherian

Anshuman Sinha

Lawrence Chou

Jean Pierre Masson

Ayaka Abe

Lingyun Hu

A method for processing sonic data acquired with a downhole sonic tool is provided. The method comprises detecting coherent noise based on a plurality of waveforms obtained from one or more receivers issued by one or more transmitters. The plurality of waveforms correspond to propagating acoustic waves in a formation. In addition, the method comprises building a slowness filter for removing the coherent noise, and applying the slowness filter to the plurality of waveforms.

Method and system for processing sonic data acquired with a downhole tool

Apparatus for acoustic measurement in a downhole environment to enable high quality measurements to be obtained in difficult logging conditions are disclosed. An example apparatus includes a downhole tool having a body with a plurality of transmitters located on the body. A receiver is located on the body a distance from the transmitters and an attenuator section is integrally formed on the body between at least one transmitter and the receiver.

Apparatus for logging while drilling acoustic measurement

Example methods, apparatus and articles of manufacture to determine anisotropy indicators for subterranean formations are disclosed. A disclosed example method includes computing a first shear slowness value from measured quadrupole waves, computing a second shear slowness value from measured Stoneley waves, and comparing the first and second shear slowness values to determine an anisotropy indicator representative of anisotropy of a subterranean formation.

Methods, apparatus and articles of manufacture to determine anisotropy indicators for subterranean formations

A method for estimating formation porosity and lithology on a real time basis during a logging while drilling operation using measured values of formation attenuation attributes for compression and/or shear.

Method for sonic indication of formation porosity and lithology

An apparatus for making a resistivity measurement of an underground formation surrounding a borehole is provided. The apparatus includes a conductive tool body, at least one current injector electrode positioned between the tool body and a wall of the bore hole, at least one current return electrode positioned between the tool body and the wall of the bore hole, an electrical measurement device configured to monitor a voltage or a current signal indicative of an impedance imbalance, a regulator connected to the electrical measurement device, whereby the regulator is configured to receive the voltage or the current signal indicative of the impedance imbalance and is configured to generate an adjustment signal based on the voltage or the current signal indicative of the impedance imbalance.

Apparatus and method for actively balancing impedance of a resistivity measuring tool

A method for estimating formation permeability from measured sonic wave Stoneley attributes and particularly the Stoneley attributes of slowness (DTst) and attenuation (ATTst), taking into consideration the existence of a heavy walled drill collar at the end of the drill string and the relative lack of borehole mud cake during a drilling operation. In the subject LWD application a real-time qualitative indication for fracture and permeable zones is estimated from Stoneley measurements. This information is useful to a driller to make important timely decisions about drilling and completion programs.

Method for permeable zone detection

A method for determining on a real time logging while drilling (LWD) basis gas within earth formations traversed by a borehole. Continuous LWD acoustic measurements are recorded and processed including coherent energy and attenuation attributes to detect downhole gas zones and kick during drilling operations.

Method for gas zone detection using sonic wave attributes

An interchangeable sleeve for a downhole tool includes a substantially cylindrical body configured to circumferentially engage the downhole tool, a blade extending radially from the body, and a transducer disposed within the blade. A drilling assembly includes a drill collar, an interchangeable blade configured to couple to the drill collar, and a transducer disposed within the blade. A size of the blade and a size of the transducer are selected based on a diameter of a borehole in which the downhole tool is to be used. A method of manufacturing an interchangeable sleeve for a downhole tool includes forming a blade on a body of the sleeve such that the blade extends radially from the body, disposing a transducer within the blade, and configuring the sleeve to circumferentially engage the downhole tool.

Apparatus and method for mounting acoustic sensors closer to a borehole wall

A method for determining on a real time logging while drilling (LWD) basis the top of cement location between casing transition zones in a borehole using at least one sonic attributes of coherent energy, attenuation and slowness as a function of at least one of depth and time.

Method for sonic indication of voids in casing cement

A novel on-the-fly data processing technique is useful for extracting signals from the azimuthal variation of the directional measurements acquired by a logging tool within a borehole. The relevant boundary, anisotropy and fracture signals are extracted from the formation response through fitting of the azimuthal variation of the measured voltages to some sinusoidal functions. The orientation of the bedding is also obtained as a result. The extracted directional signals are useful for obtaining boundary distances and making geosteering decisions. Two techniques involving inversion and cross-plotting may be employed, depending on the nature of the boundary. A Graphical User Interface (GUI) is part of a system to facilitate flexible definition of inversion objectives, for improving the inversion results, and for visualization of the formation model as well as inversion measurements.

Directional electromagnetic wave resistivity apparatus and method

Wellbore apparatus including an elongated tubular adapted for disposal within the wellbore. The tubular having an elongated recess formed on its exterior surface along the longitudinal axis. The recess is adapted to accept and house a component therein. A shield disposed within the recess and adapted to slide to a selected position therein, covering a housed component. The sliding shield and housed component are retained within the recess by a retainer system using minimal fasteners.

Wellbore apparatus with sliding shields

Acoustic transducers configured with integrated electronics technology are adapted to digitize signal data close to the transducer. The transducers are packaged with a reduced number of elements and sealed for exposure to harsh environments, without oil compensation. A transducer assembly includes a frame, an acoustic transducer element disposed on the frame, and an electronics module disposed on the frame and linked to the acoustic transducer element. The pressure and temperature tolerant electronics module is adapted to process a signal associated with the transducer element.

Integrated acoustic transducer assembly

A method for distributed processing in a subsurface environment includes running a local program on a local computation unit, wherein the local program is configured to call a remote procedure to be executed by a remote computation unit, wherein the local computation unit and the remote computation unit are disposed in a subsurface environment; initiating a remote procedure call; executing the remote procedure on the remote computation unit, while the local computation unit performs another operation; and returning a result from the executing the remote procedure to the local computation unit.

Distributed processing system for subsurface operations

Transverse or tilted magnetic dipole antenna systems are used for electromagnetic logging measurements to determine the anisotropic resistivity of subsurface formations. Combined measurements between transverse or tilted antennas, as well as axial antennas, are used to compensate for receiver antenna mismatch in the system. Some embodiments use model-based parametric inversion to estimate the anisotropic resistivity in the presence of invasion and shoulder-bed effects.

Propagation based electromagnetic measurement of anisotropy using transverse or tilted magnetic dipoles

The invention relates to a device for measuring an electrical parameter through electrically-conductive casing, said device including a current injection electrode () and a measurement electrode () on one side of the wall of the casing (). According to the invention, the injection electrode () is associated via a first magnetic coupler () with a current source () and the measurement electrode () is associated via a second magnetic coupler () with a measurement device () situated on the other side of the wall.

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Machida, Japan

Alain M Dumont