Abstract: A method for downhole event detection includes measuring a parameter of a wellbore using a first sensor of a drill string, and measuring the parameter of the wellbore using a second sensor of the drill string. The method also includes detecting, by surface equipment, an event in the wellbore based on a first set of measurements provided by the first sensor, and detecting, by the surface equipment, the event in the wellbore based on a second set of measurements provided by the second sensor. The method further includes assigning, by the surface equipment, a probability value to the event based on the event as detected in the first set of measurement values and the event as detected in the second set of measurement values.

Abstract: An along string measurement tool may include an elongate body configured for loading into a drill string and a sensor array arranged on the body. The sensor array may include a first sensor arranged at a first sensor location on the body and the first sensor may be oriented relative to the body and configured for sensing annular pressures in a wellbore. The sensor array may include a second sensor arranged at a second sensor location on the body and the second sensor location may be spaced longitudinally along the body from the first sensor location by a first distance. The second sensor may be oriented relative to the body and configured for sensing annular pressures in a wellbore.

Abstract: The examples described herein relate to methods and apparatus for cleanup prediction and monitoring. A disclosed method of predicting cleanup of a sample fluid obtained by a downhole tool includes drawing the sample fluid into the downhole tool via a probe assembly; measuring optical densities of the sample fluid at a plurality of different respective times; selecting at least some of the measured optical densities as fitting points; identifying one or more inversion parameters; and performing, via a processor, an inversion using the fitting points, the inversion parameters and simulation data to generate data associated with a predicted cleanup of the sample fluid.

Abstract: A method for enhancing axial resolution of a well logging instrument includes classifying a formation into a plurality of single well log measurement value zones to generate a squared well log. A response function of a well logging instrument is decomposed into a plurality of wavelets. The wavelets are convolved with the squared well log to generate a simulated tool response. The simulated tool response is compared to a measured tool response in the formation. The decomposing is repeated with different coefficients for each wavelet and the convolving is repeated until a mismatch between the simulated tool response and the measured tool response falls below a measurement uncertainty of the well logging instrument.

Abstract: A system and methods for drilling a well in a field having an existing well are provided. Specifically a method of drilling a new well in a field having an existing well includes drilling the new well using a bottom hole assembly (BHA) having a drill collar divided by an insulated gap, generating a current on the drill collar of the BHA while drilling the new well, and measuring from the existing well a magnetic field caused by the current on the drill collar of the BHA. Using measurements of the magnetic field, a relative position of the new well to the existing well may be determined.

Abstract: A system and methods for drilling a well in a field having an existing well are provided. Specifically a method of drilling a new well in a field having an existing well includes drilling the new well using a bottom hole assembly (BHA) having a drill collar divided by an insulated gap, generating a current on the drill collar of the BHA while drilling the new well, and measuring from the existing well a magnetic field caused by the current on the drill collar of the BHA. Using measurements of the magnetic field, a relative position of the new well to the existing well may be determined.

Abstract: A method for analyzing formation data includes decomposing the formation data into simple components that can be used to reconstruct the formation data, wherein the decomposing is performed at a first location and includes a process to minimize an overlap between the simple components; and transmitting parameters representing the simple components to a second location for reconstructing the formation data. A system for analyzing formation data that includes a processor and a memory that stores a program having instructions for decomposing the formation data into simple components that can be used to reconstruct the formation data, wherein the decomposing is performed at a first location and includes a process to minimize an overlap between the simple components; and transmitting parameters representing the simple components to a second location for reconstructing the formation data.

Abstract: The examples described herein relate to methods and apparatus for cleanup prediction and monitoring. A disclosed method of predicting cleanup of a sample fluid obtained by a downhole tool includes drawing the sample fluid into the downhole tool via a probe assembly; measuring optical densities of the sample fluid at a plurality of different respective times; selecting at least some of the measured optical densities as fitting points; identifying one or more inversion parameters; and performing, via a processor, an inversion using the fitting points, the inversion parameters and simulation data to generate data associated with a predicted cleanup of the sample fluid.

Abstract: A system and methods for drilling a well in a field having an existing well are provided. In accordance with one embodiment, a method of drilling a new well in a field having an existing well includes drilling the new well using a bottom hole assembly (BHA) having a drill collar divided by an insulated gap, generating a current on the drill collar of the BHA while drilling the new well, and measuring from the existing well a magnetic field caused by the current on the drill collar of the BHA. Using measurements of the magnetic field, the relative position of the new well to the existing well may be determined.

Abstract: A method for analyzing formation data includes decomposing the formation data into simple components that can be used to reconstruct the formation data, wherein the decomposing is performed at a first location and includes a process to minimize an overlap between the simple components; and transmitting parameters representing the simple components to a second location for reconstructing the formation data. A system for analyzing formation data that includes a processor and a memory that stores a program having instructions for decomposing the formation data into simple components that can be used to reconstruct the formation data, wherein the decomposing is performed at a first location and includes a process to minimize an overlap between the simple components; and transmitting parameters representing the simple components to a second location for reconstructing the formation data.

Abstract: Methods and systems for extracting formation properties from formation logging data is disclosed. A method includes obtaining a deconvolution filter; and processing the formation logging data using the deconvolution filter to produce estimates of the formation properties. The estimates of the formation properties may be further processed with a diffusion filter, which may be an anisotropic diffusion filter. A system for extracting formation properties from formation logging data includes a central processing unit and a memory, wherein the memory stores a program having instructions for performing a method that includes designing a deconvolution filter; and processing the formation logging data using the deconvolution filter to produce estimates of the formation properties.

Abstract: A method and apparatus are useful for decomposing a complex distribution of data by modeling the complex distribution as a sum of discrete simple distributions, and processing the simple distributions independently. The independent processing enables the complex distribution to be reconstructed without the simple distributions that are concluded to be spurious. The simple distributions preferably include one or more statistical distributions that are subject to being characterized by a reduced data set for efficient communication and reconstruction of the complex distribution. The modeling and processing steps preferably employ one or more evolutionary algorithms.

Abstract: One or more high resolution logs of a formation property having thin beds is provided for the laminated formation. From this log, the bed boundaries are detected and the facies for each of the beds detected is identified, using one or more high resolution logs of the laminated formation. Each of the identified facies is then defined. One or more squared logs for formation property is then generated by using the imported volumetric descriptions of the facies to generate a value of the formation property for each of the beds. A reconstructed log is generated and compared with a low resolution log of the formation property for laminated formation. By adjusting the values of the squared log the difference between the reconstructed log and the squared log may be minimized. An optimized squared log is output as having the square log and the volumetric analyses thereon.

Abstract: A method for determining a formation dip angle including extracting features from an acquired well log to obtain a set of features, validating the set of features to obtain a subset of features, generating a layered model using the subset of features, and generating a synthetic log using the layered model and a forward model.

Abstract: A method and apparatus for collecting data downhole in a well bore, even during drilling operations, are disclosed. The apparatus generally comprises an antenna and some associated electronic circuitry. The antenna includes a plurality of arrayed transceiver elements and the electronic circuitry steers transmission or reception through the antenna by controlling the application of power to the array elements. In operation, a transceiver unit containing such an antenna is positioned proximate a remote sensor placed into a formation. An electromagnetic signal is then steered to communicate with the remote sensor over a wireless link.

Abstract: A method for determining a formation dip angle including extracting features from an acquired well log to obtain a set of features, validating the set of features to obtain a subset of features, generating a layered model using the subset of features, and generating a synthetic log using the layered model and a forward model.

Abstract: A magnet assembly for nuclear magnetic well logging apparatus includes two diametrically opposed magnets which produce a static and substantially homogeneous magnetic field. Each magnet has a magnet axis and is partitioned into a first and a second magnet segment by a plane substantially parallel to the magnet axis.

Abstract: A method and apparatus for collecting data downhole in a well bore, even during drilling operations, are disclosed. The apparatus generally comprises an antenna and some associated electronic circuitry. The antenna includes a plurality of arrayed transceiver elements and the electronic circuitry steers transmission or reception through the antenna by controlling the application of power to the array elements. In operation, a transceiver unit containing such an antenna is positioned proximate a remote sensor placed into a formation. An electromagnetic signal is then steered to communicate with the remote sensor over a wireless link.

Abstract: The present invention relates generally to an apparatus and method for obtaining an azimuthally resolved nuclear magnetic resonance measurement of an earth formation traversed by a borehole. The measurement can be made while drilling or using a wireline tool. A receiving rf antenna having a non-axisymmetric response pattern is used to obtain the azimuthally resolved nuclear magnetic resonance measurement. The antenna employs axial currents which excite an azimuthally oriented rf magnetic field. For this situation, the static magnetic field is either radial or axial in its orientation. The antenna generates a relatively long, in axial extent, region of generally uniform static field magnitude and polarization in the formation. The present invention facilitates low profile antenna configurations that can permit dispensing with the reduction of the inner diameter of the drill collar at the rf antenna location.

Abstract: The present invention relates generally to an apparatus and method for obtaining an azimuthally resolved nuclear magnetic resonance measurement of an earth formation traversed by a borehole. The measurement can be made while drilling or using a wireline tool. A receiving rf antenna having a non-axisymmetric response pattern is used to obtain the azimuthally resolved nuclear magnetic resonance measurement. The antenna employs axial currents which excite an azimuthally oriented rf magnetic field. For this situation, the static magnetic field is either radial or axial in its orientation. The antenna generates a relatively long, in axial extent, region of generally uniform static field magnitude and polarization in the formation. The present invention facilitates low profile antenna configurations that can permit dispensing with the reduction of the inner diameter of the drill collar at the rf antenna location.