Abstract: In accordance with the present invention, rotation of the inner barrel relative of the axis of symmetry of the core barrel (indicative of core twist-off or core sand erosion during coring operations) is detected by a novel sensor combination comprising a Hall-effect device imbedded in a support sleeve of a custom safety sub attached to the outer core barrel adjacent to a single signature magnet fitted to and carried by a special support ring attached to the inner barrel. In releasably attaching the inner and outer core barrels together, the special support ring is made to be locking through operation of a series of compression strings acting between the lower surface of the ring and the inner core barrel as to wedge the upper surface of the support ring against an annular stopper ring. Result: the inner core barrel does not rotate relative to the outer core barrel during the trip down to the bottom of the well bore.
Type:
Grant
Filed:
August 12, 1983
Date of Patent:
February 19, 1985
Assignee:
Chevron Research Company
Inventors:
Frank L. Campbell, Dean C. Barnum, William C. Corea
Abstract: In accordance with the present invention, rotation of the inner barrel relative of the axis of symmetry of the core barrel (indicative of core twist off or core sand erosion during coring operations) is detected by a novel sensor combination comprising a battery-powered Hall-effect device fitted to the inner barrel imbedded in a support sleeve of a custom safety sub attached to the outer core barrel adjacent to a single signature magnet.During coring, circumferential passage of the Hall-effect device adjacent to the signature magnet (during rotation of the outer core barrel to generate a core), produces a series of signals of constant repetition rate. But with the occurrence of rotation of the inner core barrel irregular repetition intervals are produced at uphole indicating equipment connected to the Hall-effect device through conventional downhole telemetering and power generating equipment.
Type:
Grant
Filed:
August 12, 1983
Date of Patent:
February 19, 1985
Assignee:
Chevron Research Company
Inventors:
Frank L. Campbell, Dean C. Barnum, William C. Corea
Abstract: Transient change in heat flux due to ultrasmall variation in flow conditions (say from no-flow to flow) within a series of relief flowlines to pinpoint sources of plant upset, is achieved by carefully positioning (in each flowline closely adjacent to an associated relief valve) a transducer-meter for sensing transient heat flux from a selected location completely exterior of the line; and recording in sequence: (i) a base line signal indicative of a no-flow, steady state condition at each selected location along the flowline, and (ii) a transient signal indicative of a flow condition. Both types of signals are generated by a plurality of thermocouples (a thermopile) attached to each flowline in a heat flux sensing relationship that takes into account the type of fluid being monitored and the temperature gradient existing across the relief valve.
Abstract: Transient change in heat flux due to ultrasmall variation in flow conditions (say from NO-FLOW-to-FLOW) within a series of flowlines to pinpoint sources of plant upset is achieved, by carefully positioning a series of M transducer-meters for sensing transient heat flux, each meter being disposed at a selected location completely exterior of a flowline, and recording in sequence at a central control center for each of the M meters at least a transient signal indicative of a FLOW condition. For each meter, signals are generated by a thermopile attached to each flowline in a heat flux sensing relationship. Location takes into account the type of fluid being monitored, and the temperature gradient existing across the relief valve. Recordation of the sensed signals is via a series of M recorders and alarm circuits at the control center.
Abstract: In accordance with the present invention, rotation of the inner barrel relative of the axis of symmetry of the core barrel (indicative of core twist off or core sand erosion during coring operations) is detected by a novel sensor combination comprising a Hall-effect device imbedded in a support sleeve of a custom safety sub attached to the outer core barrel adjacent to a signature magnet fitted to the inner barrel.During coring, circumferential passage of the Hall-effect device adjacent to the signature magnet (during rotation of the outer core barrel to generate a core), produces a series of signals of constant repetition rate. But with the occurrence of rotation of the inner core barrel irregular repetition rates are produced at uphole indicating equipment connected to the Hall-effect device through conventional downhole telemetering and power generating equipment. Result: sticking and jamming of the core can be immediately detected and uphole parameters modified to ease unsafe conditions.
Type:
Grant
Filed:
August 12, 1983
Date of Patent:
January 8, 1985
Assignee:
Chevron Research Company
Inventors:
Frank L. Campbell, Dean C. Barnum, William C. Corea
Abstract: The disclosed invention is a method of seismic exploration using non-impulsive vibratory sources activated by stationary, Gaussian codes. The method has the channel-capacity economy of sign-bit recording and the distortion-free quality of full-waveform seismic records, even through zero memory, non-linear representations ("ZNL's") are employed either during the collection or the processing steps that produce such final records. As a result, stratigraphic facies can be both economically and surprisingly indicated.
Abstract: The present invention provides for on-site capture of carbonaceous gas at sea, for isotopic examination to enable prediction of hydrocarbon potential of an earth formation underlying a body of water.
Abstract: Transient change in heat flux due to ultrasmall variation in flow conditions (say from no flow-to-flow) within a series of relief flowlines forming a component part of a flaring system associated with a chemical or refinery complex, is surprisingly useful in pinpointing a source of plant upset. Result: corrective action can be undertaken. In one aspect, the change in flux is monitored within each major relief flowline using a heat flux transducer-meter in series with signal indicating means, such as a recorder and/or an audio-alarm system. Cascading the signal output, i.e., serially combining the outputs of N thermocouples of the transducer-meter, enhances sensitivity. In a preferred case, N is about 80 but can be as high as 320, if desired.
Abstract: Transient change in heat flux due to a small variation in flow conditions (say from no flow-to-flow or vice versa) within a fluid-carrying body under a variety of conditions, is indicated. Ultrasensitivity is achieved by cascading the signal output of a plurality of N thermocouples (i.e., a thermopile), attached to upper and lower metallic plates of a heat flux transducer-meter, the upper plate being in heat transfer contact with at least a sector of the previously-mentioned fluid-carrying body. In a preferred case, N is about 80 but can be as high as 320, if desired. Recordation of the output signals is via a recorder, although use of an audio-alarm to immediately alert an operator of a change in flow conditions, contemplated.
Abstract: A power-up storage rack for microcomputers is provided for use in accommodating automatic recharging of each microcomputer irrespective of its multiple uses by several different operators. The rack resembles an H-shaped channel beam. Recharging results via electrical interconnection of multi-pin (male-female) receptacles of the rack and microcomputer with a source of electrical energy as through a transformer. An indicator light can also be activated by such electrical engagement.
Abstract: In accordance with the present invention, fluid-flow properties of a rock sample based on NMR response of the hydrogen nuclei of interstitial fluids within the pore space of such sample, can be swiftly and accurately achieved using a computer-controlled, portable NMR instrument. The inherent instrument inadequacy of a DC field inhomogeneity is controllably augmented by an adaptively generated gating code (provided via a computer-controller in feedback relationship with an oscillator-master clock controlling a transmitter-pulser) to ensure that the nuclear magnetization precessional frequency is not a multiple of the RF interrogation frequency. Result: Even though the instrument is placed at field sites away from the usual processing center, quick analysis of rock samples as during the drilling of a well, still results.
Abstract: In accordance with the present invention, fluid-flow properties of a rock sample based on NMR response of the hydrogen nuclei of interstitial fluids within the pore space of such sample, can be swiftly and accurately achieved using a computer-controlled, portable NMR instrument. The inherent instrument inadequacy of phase background jitter is controllably augmented by generating (via a computer-initiated DC source current) a DC magnetic field gradient across the sample. Result: A DC field inhomogeneity of D gauss is discontinuously introduced to the steady DC field to maintain high data-throughput efficiency, i.e., the number of NMR responses performed per unit time. And, even though the instrument is placed at field sites away from the usual processing center, quick analysis of rock samples as during the drilling of a well, still occurs.
Abstract: In accordance with the present invention, permeability estimates of a carbonate sample based on spin echo diffusion characteristics of the hydrogen nuclei of interstitial fluids within the pore space of such sample, can be swiftly and accurately achieved using a computer-controlled, portable NMR instrument. Result: Even though the instrument is placed at field sites away from the usual processing center, quick analysis of such samples as during the drilling of a well, still results.
Abstract: The present invention indicates that acoustic characteristics associated with a first well penetrating a gas/oil-containing strata such as a sandstone, limestone or dolostone, can be normalized (and favorably compared) with similar characteristics of a second, contiguous well of known hydrocarbon potential, such characteristics being calculated and displayed by means of a machine-implemented data processing method in which well logging and geologic data are fed thereto to calculate such characteristics without the need for shear-wave velocities.In more detail, in accordance with the invention brine-saturated bulk and shear moduli, (i.e., Kw* and Gw*) of a sandstone, limestone or dolostone penetrated by the second well can be predicted as a function of, say, brine-saturated P-wave modulus (Pw*) alone (independent of shear-wave velocity). In that way, resulting acoustic values including distinct velocity and amplitude values as a function of a saturation operator can ultimately be provided.
Type:
Grant
Filed:
August 17, 1981
Date of Patent:
August 16, 1983
Assignee:
Chevron Research Company
Inventors:
Don D. Thompson, Robert J. S. Brown, Richard J. Runge
Abstract: The present invention indicates that acoustic characteristics associated with gas/oil-containing strata of an earth formation, including reflectivity coefficients can be normalized (and favorably compared) with similar characteristics calculated and displayed by means of a machine-implemented data processing method in which well logging and geologic data are fed thereto to calculate such characteristics without the need for shear-wave velocities.In more detail, in accordance with the invention brine-saturated bulk and shear moduli, (i.e., Kw* and Gw*) of the strata of interest can be predicted as a function of, say, brine-saturated P-wave modulus (Pw*) alone (independent of shear-wave velocity). In that way, resulting acoustic values including seismic velocities and amplitudes (also, reflectivities) as a function of saturation can ultimately be provided.
Type:
Grant
Filed:
November 18, 1981
Date of Patent:
August 9, 1983
Assignee:
Chevron Research Company
Inventors:
Don D. Thompson, Robert J. S. Brown, Richard J. Runge
Abstract: The present invention provides for the accurate mapping of shallow crustal earth formations by means for refractive seismic waves to identify structure as well as elastic parameters of the strata undergoing survey to indicate deposits or ore, marker rock, economic minerals and the like. In one aspect of the present invention, a "roll-along" technique is used in the field, such technique being both practical and economical. In accordance with another aspect of the invention, there is a provision for (i) accurate separation and determination of seismic shear and compressional responses using two-dimensional hodographs; (ii) stacking displays that allow for accurate identification of shape of the surveyed strata; and (iii) final depth displays of the refracting bed segments associated with seismic shear and compressional wave velocities as well as Poisson's ratio to indicate presence of ore, marker rocks, economic minerals and the like.
Type:
Grant
Filed:
February 26, 1981
Date of Patent:
August 2, 1983
Assignee:
Chevron Research Company
Inventors:
Gary S. Gassaway, Henry J. Richgels, James I. Foster
Abstract: The present invention indicates that acoustic characteristics associated with a first well penetrating a gas/oil-containing strata such as a sandstone, limestone or dolostone, can be normalized (and favorably compared) with similar characteristics of a second, contiguous well of known hydrocarbon potential, such characteristics being calculated and displayed by means of a machine-implemented data processing method in which well logging and geologic data are fed thereto to calculate such characteristics without the need for shear-wave velocities.In more detail, in accordance with the invention brine-saturated bulk and shear moduli, (i.e., Kw* and Gw*) of a sandstone, limestone or dolostone penetrated by the second well can be predicted as a function of, say, brine-saturated P-wave modulus (Pw*) alone (independent of shear-wave velocity). In that way, resulting acoustic values including distinct velocity and amplitude values as a function of a saturation operator can ultimately be provided.
Type:
Grant
Filed:
October 27, 1980
Date of Patent:
July 12, 1983
Assignee:
Chevron Research Company
Inventors:
Don D. Thompson, Robert J. S. Brown, Richard J. Runge
Abstract: The present invention provides for the accurate mapping of shallow crustal earth formations by means for refractive seismic waves to identify structure as well as elastic parameters of the strata undergoing survey to indicate deposits of ore, marker rock, economic minerals and the like. In one aspect of the present invention, a "roll-along" technique is used in the field, such technique being both practical and economical. In accordance with another aspect of the invention, there is a provision for (i) accurate separation and determination of seismic shear and compressional responses using three-dimensional hodographs; (ii) stacking displays that allow for accurate identification of shape of the surveyed strata; and (iii) final depth displays of the refracting bed segments associated with seismic shear and compressional wave velocities as well as Poisson's ratio to indicate presence of ore, marker rocks, economic minerals and the like.
Type:
Grant
Filed:
August 8, 1980
Date of Patent:
July 12, 1983
Assignee:
Chevron Research Company
Inventors:
Gary S. Gassaway, Henry J. Richgels, James I. Foster
Abstract: In accordance with the present invention, fluid-flow properties of a rock sample based on NMR response of the hydrogen nuclei of interstitial fluids within the pore space of such sample, can be swiftly and accurately achieved using a computer-controlled, portable NMR instrument. Inherent instrument inadequacies (DC field inhomogeneity and large phase background jitter) are themselves relied upon to increase the data-throughput efficiency, i.e., the number of NMR responses performed per unit time. Result: Even though the instrument is placed at field sites away from the usual processing center, quick analysis of rock samples as during the drilling of a well, still results.
Abstract: The method and apparatus of the present invention are described in which connection (and disconnection) of a plurality of geophones associated with a digital seismic data acquisition system is greatly simplified without sacrificing flexibility as to the number of geophone flyers per station or the interval spacing per station and also without the addition of separate subcabling in the internal linkage of the flyers to the field digitizing equipment. The apparatus includes a multiple-phone flyer-jumper connected to each channel of a remote data acquisition and telemetering circuit (RDATC). Each RDATC acts in combination with a group of geophone flyers, say four, to store, amplify, filter, gain control and digitize analog data from the flyers and then telemeter the data to recording circuitry in the field truck. In accordance with the present invention, each jumper-flyer includes a central multi-conductor cable segment terminating at each of its ends in the central leg of a multi-armed connector.