Abstract: A coupler system comprising: a coupler; first, second, and third bulkheads included in the coupler; an electrical switch included in the coupler, wherein the electrical switch includes a printed circuit board (PCB); wherein the first, second, and third bulkheads respectively include first, second, and third bulkhead electric contacts, and the first, second, and third bulkhead electric contacts include no resilient members; wherein: (a) the first bulkhead is to couple to a first proximal electrical contact of a proximal connector of a perforation gun, (b) the second bulkhead is to couple to a second proximal electrical contact of the proximal connector of the perforation gun, and (c) the third bulkhead is to couple to a distal electrical contact of a distal connector of another perforation gun. The coupler includes proximal and distal sacrificial blast plates.

Abstract: In acoustic well logging, for each inversion depths of a well at which logging of data occurs, acoustic log signals representative of waveforms received at acoustic receivers are processed in a frequency domain to derive field dispersion curve(s). A neural net is operated to generate formation shear slowness value(s) from the curve(s), and resulting signal(s) indicative of shear slowness values are saved, transmitted, plotted, printed or processed. An apparatus for carrying out the method includes a logging tool having at least one activatable acoustic wave source; spaced and acoustically isolated therefrom in the logging tool an array of acoustic detectors that on the detection of acoustic wave energy generate electrical or electronic log signal(s) characteristic of acoustic energy waves detected by the acoustic detector(s); and at least one processing device associated with or forming part of the logging tool for processing the log signal(s).

Abstract: A downhole tool connection comprises (i) a tool intended for downhole use and including a connection section protruding therefrom in use in an uphole direction, the connection section supporting two or more first connectors spaced from one another and operatively connected to the tool; and (ii) a cable carrier moveable in an in-use downhole direction towards the connection section. The cable carrier supports (a) one or more cables and (b) two or more second connectors spaced from one another and operatively connected to at least one cable. Pairs of the first and second connectors are mutually connectable, on movement of the cable carrier towards the connection section to increase the proximity of the connectors of the pairs, in a manner effecting electrical transmission between the connectors of each pair. At least one pair of the connectors connects inductively, and at least one pair of the connectors connects conductively.

Abstract: An acoustic dipole waveform generator has a hollow housing defining an elongate axis and having secured therein at least a force reaction member defining at least a force reaction surface and having hingingly secured thereto an actuator element. The piezoelectric actuator elements define mutually non-aligned length change axes and extend from the reaction member towards at least one moveable piston member hingingly secured to at least one of the actuator elements inside the housing. The piston member is constrained to move in a direction extending perpendicular to the axis, the piston member defining respectively at mutually spaced locations in the housing a pair of heads that, on movement of the piston member, each generate a respective pressure wave and the housing permitting transmission of the wave externally thereby permitting generation of a dipole pressure waveform externally of the housing on changing of the lengths of the actuator elements.

Abstract: Apparatus (10) for use in determining values of properties of n layers (16,17) of a borehole (11) formed in the Earth's crust (12) comprises a plurality of at least (2n-1) sensor members (19,21,22) of mutually differing, known or calculable, geometric factors, as defined with reference to a sample under investigation comprising n layers. The sensor members (19,21,22) are capable of detecting reflected or transmitted electromagnetic energy and the apparatus (10) includes one or more supports (24,26?) for supporting the sensor members (19,21,22) in a said borehole (11) adjacent and/or in contact with one or more said layers (16,17), the apparatus (10) being capable of causing transmission of electromagnetic energy along, and/or reflection of electromagnetic energy at, each sensor member (19,21,22) in a manner permitting the calculation of values of properties of such layers (16,17) based on reflected or transmitted energy values detected at the sensor members (19,21,22).

Abstract: A method and a resistivity image logging tool connected or connectable to one or more processing devices process geological log data to construct missing information from destroyed or occluded parts using cues from observed data. The geological log data signals can be generated through use of the logging tool having one or more electrodes interacting with a formation intersected by a borehole. The processing involves the steps of: in respect of one or more data dimensions associated with missing values in a log data set, decomposing the signal into a plurality of morphological components; and morphologically reconstructing the signal such that missing values are estimated.

Abstract: Apparatus (57, 58) for determining permittivity in a downhole location comprises a sensor (57) including an elongate conducting line (62) supported on or adjacent a first side of a dielectric substrate (61). The sensor (57) also includes at least one conducting ground element (26, 27) that is spaced from the conducting line (62), the conducting line (62) being capable of juxtaposition to a downhole borehole wall (12). The apparatus further includes connected respectively to spaced locations along the conducting line at least two terminals (31, 32; 63, 64) of a vector network analyser (57b) that is capable of detecting one or more signal reflection characteristics whereby when the sensor (57) is juxtaposed to a borehole wall (12) the vector network analyser (57b) generates one or more signals that are processable to indicate the relative permittivity of rock (39) in which the borehole is formed.

Abstract: Logging tool communication apparatus (10), for carrying out a downhole communication method, comprises rotatable and/or longitudinally reciprocable drill pipe (12) including fixed or capable of being fixed in a co-rotative and/or co-reciprocable relationship at an in-use downhole end an in-use downhole logging tool (27). The logging tool (27) includes a movement sensor (33); and the apparatus (10) includes a motor, at a location remote from the logging tool (27), for causing rotation and/or reciprocation of the drill pipe (12) in a borehole or wellbore (18). The apparatus (10) includes one or more control elements for selectively controlling operation of the motor so as to cause selective rotation and/or reciprocation of the drill pipe (12) which causes movement of the logging tool (27), when fixed to the drill pipe (12), in a manner that is detectable by the movement sensor (33).

Abstract: A downhole tool coupling (10) comprises first (11) and second (12) downhole tool elements that are securable one to the other in a releasably locking manner by moving the tool elements from a longitudinally relatively less proximate, especially overlapping position into longitudinally relatively more overlap with one another. The first downhole tool element (11) supports a first inductive, capacitative and/or magnetic energy coupler (23) and the second downhole tool element (12) supports a second inductive, capacitative and/or magnetic energy coupler (24). The first and second energy couplers (23, 24) are moveable from an energetically uncoupled position when the tool elements (11, 12) are in the longitudinally relatively less overlapping position to an energetically coupled position when the first and second downhole tool elements (11, 12) overlap relatively more.

Abstract: To process geological log data, a two-dimensional set of log values recorded at a plurality of points is obtained about a borehole periphery, and over a chosen length along the borehole. The set of log values are decomposed by identifying in the set one or more main functions indicative of one or more main geological layer features of the rock penetrated by the borehole and removing log values corresponding to values of the main functions from the set of log values. Further decomposing the set of log values can be performed, as necessary iteratively, based on one or more subsidiary functions. The log values of the set remaining after identification and removal of values are designated as texture. Functions indicative of the main and subsidiary layer features and the texture are used to construct a synthesized volume representing the rock removed during creation of the chosen length of the borehole.

Abstract: A logging tool or sub (10) for downhole use comprises an elongate logging tool body (11); one or more moveable reaction members; and a locking member for the reaction members. At least one arm (12) at a first location is pivotably secured to the body (11) to be extensible therefrom and compressible towards the body (11); and at a second location spaced from the first location is pivotably secured to a locking member (18); and a stop member (22) fixed or fixable relative to the body (11). The locking member (18) defines a moveable end (19) remote from the second location and moveable relative to the arm (12) between at least a first position in which force tending to compress the arm (12) towards the body (11) causes the end (19) to move away from the stop member (22), and a second position in which force tending to compress the arm (12) towards the body (11) causes the stop member (22) to resist movement of the locking member (19) thereby preventing compression of the arm (12) towards the body (11).

Abstract: A method of improving geological log data obtained from use of one or more logging tools, the method including the steps of (i) from raw log data recorded by the said one or more logging tools, respectively deriving according to differing first and second derivation methods a first log data set and a corresponding second log data set having the same vertical response attribute, (ii) mixing, to form resulting log curves, the first and second log data sets, the extent of mixing varying from one logged depth to another in relation to a function of (a) the semblance between the recorded log data and reference log data of a differing kind from the recorded log data and (b) the activity of one of the said first and second log data sets at each logged depth; and (iii) displaying transmitting, saving, outputting or processing one or more resulting improved log curves.

Abstract: A method and a resistivity image logging tool connected or connectable to one or more processing devices process geological log data to construct missing information from destroyed or occluded parts using cues from observed data. The geological log data signals can be generated through use of the logging tool having one or more electrodes interacting with a formation intersected by a borehole. The processing involves the steps of: in respect of one or more data dimensions associated with missing values in a log data set, decomposing the signal into a plurality of morphological components; and morphologically reconstructing the signal such that missing values are estimated.

Abstract: A method of processing borehole log data to create one or more image logs involve modelling the log data as components of an image in the form i(x, y)=l(x, y)×r(x, y) (1), in which i(x, y) is an image representative of the log data, l(x, y) denotes an illumination value of the image at two-dimensional spatial co-ordinates x, y, and r(x, y) denotes a surface reflectance value at the co-ordinates x, y. Equation (1) is transformed to a logarithmic domain, and a Fourier transform is obtained of the resulting logarithmic domain expression to obtain a Fourier domain expression. The Fourier domain expression is high-pass filtered, and an inverse Fourier transform is obtained of the resulting filtered Fourier domain expression. An exponential operation is performed on the result of inverse Fourier transform to obtain a filtered image model expression. Values of the filtered image model expression are mapped to respective color values across the range of the filtered image model expression values.

Abstract: A wireline deployed fluid blasting tool for removing obstructions from oil and gas wellbore tubing is disclosed. The tool has an inner tubular mandrel retaining a releasable outer sleeve creating an annular fluid passage in communication with fluid ejection ports. Resilient seals seal the annulus between the tool and the wellbore tubing allowing fluid pressure above the tool to advance the tool through the tubing. Fluid enters the annular fluid passage through fluid perforations in the outer sleeve to exit the fluid ejection ports to create a fluid blast to remove obstructions. The outer sleeve shifts along the inner mandrel by fluid pressure to open fluid inlet passages into the inner mandrel allowing fluid to enter and exit through the mandrel while bypassing the annular fluid passage and fluid ejection ports to facilitate pulling the tool from the tubing.

Abstract: A logging tool or logging tool sub (10) for downhole use comprises an elongate cylindrical body (11) having supported thereby one or more movable landing extensions (12) that are movable between an extended position in which part of each said movable landing extension protrudes beyond the exterior of the cylindrical body (11) so as to define one or more exposed landing surfaces that are engageable with one or more landing surfaces (21) of a further component; and a retracted position in which each said movable landing extension (12) protrudes externally of the cylindrical body no further than the exterior thereof (11).

Abstract: A transmitter for an acoustic logging tool includes an elongated housing, an acoustic energy generator, and a driver. The elongate housing defines a hollow interior and supports an acoustic energy generator, which includes four mutually orthogonally orientated bender bars that are electrically driveable to flex within the hollow interior in order to generate pressure-derived waves in a fluid surrounding the transmitter in use. The housing includes one or more transmissive windows via which flexing of the bender bars gives rise to propagation of one or more said waves in a said fluid. The driver electrically drives the bender bars to flex so as selectively to generate monopole, dipole, or quadrupole waves in a said fluid, with the poles of the dipole and quadrupole when generated selectively being aligned with normals to pairs of the bender bars or rotated 45° relative thereto.

Abstract: A downhole seal element (10) comprises a cup portion (11) formed of or including a resiliently deformable material. The cup portion (11) extends between on the one hand a nose part (12) comprising an annulus intended for sealingly mounting the seal element on a mandrel (22) and on the other hand a skirt (13), the seal element flaring in shape between the nose part (12) and the skirt (13). The skirt includes extending therefrom away from the nose part (12) a plurality of elongate, flexible limbs (18) that are spaced at intervals about the skirt (13).

Abstract: A method of processing geological log data to construct missing information from destroyed or occluded parts using cues from observed data comprises the steps of: a. in respect of one or more data dimensions associated with missing values in a log data set, decomposing the signal into a plurality of morphological components; and b. morphologically reconstructing the signal such that missing values are estimated.

Abstract: A method of detecting an edge of a geological characteristic in a borehole comprises, in respect of an image log of a length of a borehole, carrying out the steps of a gradient-based edge detection method, a phase congruence-based edge detection method or a combination of such methods as preliminary, pre-processing stages. Subsequent steps of the method may include operating a relatively computationally simple process to identify sinusoids among detected edge features; and a relatively computationally complex process for parameterizing the thus-identified sinusoids.