Abstract: A latching mechanism used to couple external devices to marine seismic streamer cables is disclosed. The latching device universally couples to collars predominantly used in the seismic industry. A mounting bracket or shank is provided which is coupled to the external device. The shank has a lug or finger fixed therein which extends from a mounting surface. Adjacent the lug is a latching device which is comprised of a cylinder having a cam defined at the upper end. The cylinder is recessed within the shank so that the cam and the lug are engaged with an aperture defined in the collars attached to the streamer cable. A lever extends from the cylinder through the exterior of the shank so that an operator may rotate the cylinder, turning the cam in the aperture to a locking position. A spring applies a tensile force to the cylinder, drawing the cam down against the aperature, and pulling the shank tight against the collar.

Abstract: Apparatus for coupling wireline tools to coil tubing wherein a pull-out, disconnect, is provided. The pull-out consists of two tubular members with flared, bell-shaped portions, one such portion being coaxially disposed within the other. A ferrule applies pressure to the interface of the surfaces of said flared portions. Sufficient tension on the coil tubing pulls the flared portion of the interior member through the neck and out of the exterior member. Pilot valves prevent intrusion of bore hole fluid into the coupling device during logging and into the coil tubing if a pull-out has been effected.

Abstract: A method for identifying anomalous noise amplitudes in seismic records by deriving a measured amplitude factor over predetermined periods of time or time windows for a predetermined number of traces comprising the records is disclosed. A noise-free amplitude factor for the same periods of time and number of traces is also computed using a Gauss-Siedel method of matrix inversion. A ratio of the measured and noise-free amplitude factors is made to determine a correction factor which is compared to a user defined threshold value for determining a presence of anomalous noise amplitudes in the seismic records. Based on the comparison of the correction factor to the threshold value, the user determines whether to suppress or correct traces experiencing the anomalous noise amplitudes.

Abstract: A method and apparatus is disclosed for accurately determining the spatial orientation of planar and linear features expressed along the exterior surface of a core sample. The core sample is positioned in a plurality of sequentially generated orthogonal electromagnetic fields. The core sample is retained by a device which allows complete rotation of the core sample about a predetermined axis while positioned in the electromagnetic fields. A stylus containing an antenna for detecting the electromagnetic fields is used to trace surficial features along the core exterior while simultaneously detecting components of the generated electromagnetic fields. The stylus provides an output to an analyzing device which calculates the coordinates of points along the core features. The coordinates are passed to a computer which has also been monitoring the rotation angle of the core.

Abstract: Apparatus for positioning a detector at a plurality of depth locations within a borehole includes an elongated body member having a pair of diametrically opposed hydraulic pad displcement members mounted thereon. A pad mounting member is pivotally attached to each pad displacement member and a pair of borehole wall contacting members are pivotally attached to each pad mounting member. A signal detector is mounted behind one or more of the pad members. At each test depth a hydraulic power system deploys the pad displacement members from the body to an extended position and extends the wall engaging pad members into contact with the borehole wall. A redundant hydraulic safety system is provided in case of electrical system failure for releasing the pad member.

Abstract: A method for quantitative mineral analysis of core samples obtained from oil and gas wells is disclosed. The method includes the steps of grinding the sample to very small particle size and combining the sample with a carrier material such as KBr to form a pellet. The pellet is observed in a Fourier transform infra-red spectrometer and the resultant spectra compared with those of known standards in a digital computer to produce a quantitative analysis of the material.

Abstract: The expanded-beam fiber, fiber-optic connector assembly includes a body having a longitudinal bore for receiving an aligning sleeve therein which has an axial hole for receiving a strand of optical fiber. The optical fiber may be surrounded by a stress member which is firmly anchored by a crimping sleeve to the exterior of the body. The optical fiber extending through the aligning sleeve is cleaved to within 0.020 inch of the end of the sleeve that slideably receives a ferrule containing a self focusing microlens in one end. The aligning sleeve mates with the ferrule such that the end of the optical fiber is axially aligned and in contact with the microlens. Two such connectors may be coupled together by an aligning ferrule such that the microlenses of each are no more than one quarter of an inch apart.

Abstract: An improved apparatus for generating a seismic wave in a borehole in the earth is disclosed. A portion of the borehole, which may be the bottom of the hole or any other point along its length, is selected as the site for seismic wave generation. A device is provided to oscillate the borehole fluid in a selected portion of the borehole to establish a resonant standing pressure wave of desired frequency within the fluid. The wave is maintained by continuing to supply energy to the fluid to replace losses due to fluid friction, structural losses and radiated acoustic energy. The standing wave thus created is radiated through the borehole wall into the earth and is eventually received by seismic detectors located on the surface.

Abstract: The instant invention is a method for accurately estimating the subsurface porosity and porosity-thickness of an interval of interest. A seismic acoustic model is constructed from data collected in a seismic survey. The acoustic model provides information from which predicted porosity values may be calculated. The predicted porosity valves are then cross-plotted with actual porosity valves obtained from well information, providing an accurate estimate of porosity away from the well locations. Porosity thickness is determined using the thickness information provided by the well data.

Abstract: A streamer-cable assembly is provided having a tubular outer jacket enclosing an open-cell foam case providing an axial hole for retaining a plurality of pressure sensors. A plurality of off-axial holes provide passages for the transmission bundle. Longitudinal channels along the exterior receive stress members which provide longitudinal rigidity to the streamer. Cable noise associated with cable jerk, and cable-whip or vibration is radically reduced by the foam core and rigid stress members.

Abstract: A triggering device for actuating a plurality of serially coupled fluid samplers disposed in a borehole includes a housing having a pair of pistons, each coupled to opposing valves in the tandem fluid samplers. The pistons are locked apart by locking bearing urged against the housing by one of the pistons. Closing of the valve in the upper sampler drives one piston releasing the locking bearing and allowing the other piston to move upwards, thus actuating the lower sampler.

Abstract: A computationally-economical method for converting a set of aerially-distributed seismic traces into a new, clearly-resolved, three-dimensional display of a volume of the earth without use of dip-dependent or azimuth-dependent migration velocities.

Abstract: A stilt structure for a vibrator assembly in which the spider members on each end of the actuator are pivotally coupled to the vertical supports (stilts). The pivotal connection allows rotation of each component thereby eliminating induced bending moments between the spider members and the vertical supports.

Abstract: An analog signal is oversampled as a digital time series. The data samples are divided into an even and an odd sequence. Each sequence is independently low-pass filtered and the resulting two reconstructed sequences will be identical to each other and to the original if no isolated error is present in the original sequence. When the three sequences are not equal, an error exists. By noting the location or sample number of the error, the exact location of the error can be determined and the correctly reconstructed sample value can be used to replace the erroneous sample in the original sequence.

Abstract: Seismic data are passed through a preselected number of migration stages. During each stage, data are migrated a plurality of times, where the migration-velocity function is a minor fraction of the velocity required to fully migrate the data in a single stage. The cascaded migration migrates data having steeply-dipping events with greater accuracy and with less noise or artifacts than does a single-stage migration.

Abstract: A radiation source launches a radiant pulse of a desired width into a plurality of parallel-coupled optical sensors for modulation by a quantity to be measured. The modulated output from any two sensors taken in all combinations are interferometrically combined to generate a series of time-separated interference patterns. The interference patterns are probed by a photodetector and vectorially combined to provide the vector gradient of the quantity under measurement.

Abstract: A computationally-economical method for converting a set of areally-distributed seismic traces into a new, clearly-resolved, three-dimensional display of a volume of the earth without use of dip-dependent or azimuth-dependent migration velocities.

Abstract: A U-tube manometer for calibrating a differential pressure transducer or the like, wherein the height of working fluid in each column may be determined by the two-way travel time of an acoustic pulse launched from the top of each column against the top of the working fluid. The propagation velocity of each acoustic pulse is determined by a calibration target integral with each tube and located above the working fluid at a predetermined distance from each acoustic source. The generation and detection of each acoustic pulse is monitored by a remote processor and recorder which calculates the pressure differential between the two tubes of the manometer.

Abstract: A core holder is provided for making petrophysical measurements of core samples from a borehole. The core holder is designed to make resistivity measurements and fluid-flow tests under reproduced conditions of in-situ fluid saturation, reservoir pressure and reservoir temperature.

Abstract: An active, low-profile hydrophone for use in aquatic environments having substantially turbulent flow conditions. The hydrophone is generally pisciform such that it may lie substantially flat on the water bottom and oriented in the current so as to reduce ambient noise associated with the turbulent flow. The enclosed sensors are oriented such that they are insensitive to acceleration and are coupled to a unity gain amplifier network also contained within the hydrophone.