Abstract: A method of deterministically computer generating a model of a response voltage waveform of a seismic receiver employed in a seismic, particularly marine, data gathering system, the model incorporating factors that have been identified as significant contributions to amplitude, such as directivity, divergence, attenuation, interbed multiples, and transmissivity. The model is generated from the mathematical manipulation of well log data and data gathering system characteristics into a seismic range equation, namely: ##EQU1## where E.sub.r (f)=received energy densityE(f)=radiated energy densityD(.theta..sub.s, .phi..sub.s, f)=source directivity along .theta..sub.s, .phi..sub.s direction at the sourceA.sub.c (.theta..sub.H, .phi..sub.H, f)=Capture area along .theta..sub.H, .phi..sub.H direction at the hydrophone arrayR.sub.T =target reflection coefficientD.sub.

Abstract: A device and method for suppressing acoustic tube wave noise in a borehole. The device comprises an absorptive material that is positioned in a borehole so that the device will encounter and absorb the tube waves before the waves are detected by receivers. The device can also contain a housing in which to place the absorptive material. The housing can also be surrounded by an absorptive material to help absorb energy reflecting off the borehole wall.

Abstract: A method of locating leaks in pipelines and associated facilities and a novel leak-detection test-fluid are disclosed. The novel test-fluid, comprising an odorant (preferably dimethylsulphide), a mutual solvent and water, is injected into a pipeline or facility so that the test-fluid escapes through the leak and an odorant which, by virtue of its chemical and physical properties, is released from other test-fluid components to be detected in the vicinity of the leak.

Abstract: A microaccumulator for receiving and holding fluid under pressure, and for measuring fluid volume changes in one aspect in very small amounts, and for indicating the amount, the microaccumulator having a body with an interior cavity for receiving the fluid and a piston movably disposed therein which moves in response to a change in fluid amount, the piston having a sensor interconnectible with a monitor and/or system control (e.g. a computer) which can control monitor and/or record changes in the amount of fluid. A triaxial test apparatus for low permeability rock (e.g. shales) using such a microaccumulator. Methods for triaxial tests and for the use of such devices.

Abstract: This invention relates to a closed-loop, multi-stage compression refrigeration system which uses a multi-component refrigerant wherein the compressed refrigerant is partially condensed, and the vapor and liquid streams are separated in a primary separator. The liquid stream passes through several expansion stages, providing a refrigeration duty at each stage. That portion of the refrigerant which is vaporized is recycled to an intermediate stage of the multi-stage compressor. The vapor from the primary separator, which is rich in the light component, is condensed and expanded to the lowest stage of refrigeration, providing maximum refrigeration duty for a given refrigerant composition and compressor suction pressure.

Abstract: A positive displacement piston pump that can pump multiphase fluids by separating the fluid into its different components inside the pump before pumping the fluids. A reciprocating piston mounted inside the pump barrel divides the barrel into two chambers, with each chamber having an opening. Accumulators located above the chambers and below the pump inlet provide a space for the multiphase fluids entering the pump to separate before entering the chamber. As the multiphase enters each accumulator, gravity causes the liquid to sink and the gas to rise separating the different phases, preferably allowing liquid to enter the chambers before the gas. When the piston moves through the chambers forcing the fluid through outlet valves located on the top side of the chamber the gas will exit the chamber, the accumulator, and the pump before the liquids.

Abstract: Improvements in centrifugal pumps are disclosed which minimize flow recirculation effects induced by wear ring leakage flow. The improvements may be used individually or in combination and comprise deflector means attached to the impeller, diverter means attached to the casing or impeller or wear ring inducer means.

Abstract: A method for increasing the end-bearing capacity of an open-ended pile is disclosed. The method comprises first determining the quantity of granular material necessary to insure full mobilization of the available capacity of the soil at the tip of the pile. The granular material is then inserted within the pile on top of the soil column, thereby causing the column of granular material to plug or lock-up within the pile during transient loading and thus mobilize the available capacity.

Abstract: An improved earth drilling bit and method that cuts at least one annular kerf ahead of at least one rolling cutter and provides for rock chip removal and bit cooling thereby increasing drilling rate and bit performance. One embodiment of the invention includes a bit body having a lower end forming an annular kerf cutter for cutting an outer annular kerf, an inner drill member positioned concentrically within the bit body having a lower end forming an annular kerf cutter for cutting an inner annular kerf, and at least one rolling cutter mounted to the bit body and extending from the interior of the outer kerf cutter to the longitudinal axis of the drill bit. Other embodiments include a chipway port defined by the drill bit for channeling rock chips away from beneath the bit; baffles for directing and accelerating drilling fluid flow; cutting edges having connecting webbs providing egress for rock chip and drilling fluid; and slots extending along the bit body for reducing surge and swab pressure.

Abstract: Methods for the construction of and controlled phase marine source arrays provide phase control for source array pulses radiated into emergence (or incidence) angles of interest. Phase control means that the phase spectra associated with source array pulses radiated in a generally downgoing direction, (i.e. for angles of emergence from the array that are of interest) will match the phase spectrum associated with a vertically downgoing source array pulse out to the "ghost-notch" frequency associated with the vertically downgoing pulse. Although the range of emergence angles over which phase control is possible may be limited by the array geometry, proper attention to and control of array geometry and the radiation characteristics of the individual array source elements provide such controlled phase marine arrays.

Abstract: A sleeve for a seismic air gun exhaust chamber is disclosed. The sleeve prevents water from accumulating in the air gun exhaust chamber when the air gun is vertically positioned and provides a convenient method for regulating the volume of the air gun exhaust chamber, and thus the frequency of acoustic energy emitted by the gun. The sleeve is characterized by a false bottom which is connected to the main chamber by an orifice and passages.

Abstract: A method of recovering hydrocarbons from subterranean reservoirs by the use of a viscous microemulsion form the single phase region of the ternary diagram of a microemulsion system that is optimal at the reservoir salinity is disclosed. The microemulsion is obtained by first determining the reservoir salinity and viscosity, then determining the oil molar volume that corresponds to a microemulsion having the reservoir viscosity, then determining the oil or mixture of oils that correspond both to the oil molar volume determined above and the reservoir salinity. The oil is then used to create a microemulsion within the single phase region of an optimal microemulsion.

Abstract: A geophone configuration is disclosed that includes an elongated extension or spike that couples with the soil in the hole made by the spike in the region near the end of the spike without hard or firm coupling with the soil above that region. A bow spring or drill bit larger in diameter than the diameter of the spike can be used for achieving predominant contact for the coupled region compared to soil opposite the remainder of the spike. Alternately, a weighted tip can be employed to achieve relative superior coupling by weight compared with the less heavy region of the spike above such weighted tip.

Abstract: The invention relates to a method for separating two primary components of a multi-component feed stream (e.g., methane and nitrogen) in the presence of a third, freezable component (e.g., carbon dioxide) having a relative volatility less than that of either primary component. The inventive process employs both a distillation section and a controlled freezing zone ("CFZ"). The freezable component is allowed to freeze in the CFZ, and the resulting solids are collected at the bottom of the CFZ. The CFZ also produces a vapor overhead product enriched in one of the primary components and a liquid bottom product enriched in the other primary component. The solids of the freezable component are melted and mixed with the CFZ liquid bottom product to form a liquid feed stream for the distillation section which operates like a conventional distillation section, while tolerating significantly high concentrations (i.e., >0.

Abstract: A method for monitoring in situ miscibility of a solvent with reservoir oil by using at least two tracers having different boiling points and being miscible with the solvent. The tracers are mixed with the solvent, injected into a well and produced from another well. Appropriate analysis of the produced tracers will reveal whether the solvent is first contact miscible. The tracers are selected from the group consisting of halocarbons, halo-hydrocarbons, sulfur hexafluoride, tritiated or carbon 14 tagged hydrocarbons, tritium gas and radioactive isotopes of inert gases.

Abstract: Method and system for creating a vertical seismic profile (VSP) whereby the spacing interval between units, either seismic sources or receivers, in a borehole increase exponentially as their distance from the surface increases, and the spacing interval between units, either seismic sources or receivers, along the surface of the earth decreases exponentially as their distance from the surface intercept of the wellbore increases. In a preferred embodiment of this invention, the common depth point (CDP) fold of the data gathered is substantially flattened across the reflectors surveyed.

Abstract: A method for high-resolution seismic recording with increased bandwidth using detectors planted at shallow depths below the earth's surface. In one embodiment, an optimum depth where the amplitudes of high frequency signals increase relative to that of the noise during high-resolution recording is determined, geophones are then planted at that optimum depth and signals are recorded at that depth. To find this optimum depth, detectors are planted at various depths below the earth's surface in order to record the signals at those various depths. The frequency spectra for each detected signal is generated and a velocity profile of the depths covered by the detectors is also generated from the signals. The bandwidth of the frequency spectra and the velocity profile are used to determine a depth for planting the detectors that is closer to the earth's surface than the depths previously considered.

Abstract: A method for non-abrasively running tubing comprising suspending the tubing from the face of the uppermost collar of the tubing by resting the face upon a support shoulder, making up a new tubular with collar into a tubular unit, attaching a non-abrasive lift unit to a tubular unit, stabbing the new tubular into the upper collar, non-abrasively making the connection tight, and lifting the lift unit to raise the string, the method being appropriately reversed for pulling the string.

Abstract: A method for determining the relative HAZ toughness of steel. The method comprises determining at least two thermal cycles of the steel for at least one weld heat input value and then simulating the HAZ that would result if the steel were actually welded in accordance with those thermal cycles. The steel is then fractured to determine various fracture properties, each of which may be used to determine the midpoint transition temperature associated with the fracture property used. The midpoint transition temperature is compared to a previously determined standard maximum midpoint transition temperature and if it is greater than the standard, the steel may have low HAZ toughness, but if it is less than the standard, the steel may have a high HAZ toughness.

Abstract: Method and apparatus for acoustic wave generation and transmission into a subsurface earth formation. A logging sonde adapted to be suspended in a borehole within the formation houses a generator means for simultaneously generating a plurality of acoustic waves traveling in the direction of and spaced substantially evenly about the .[.logitudinal.]. .Iadd.longitudinal .Iaddend.axis of the sonde. An acoustic energy reflector means within the housing reflects the waves radially outwards of the axis and into the formation at angles generally perpendicular to the axis. Detectors within the housing spaced longitudinally from the generator and reflector detect acoustic energy in the formation resulting from the reflected waves.