Abstract: A system for synchronizing a seismic system having multiple subsystems. A control system transmits a message to selected subsystems and an internal subsystem counter is zeroed to a selected epoch. Depending on the message or on an internal instruction code, each subsystem initiates an event or sequence of events synchronized to the selected epoch. The system is based on the relative occurrence of cyclic events and does not depend on the transmission of an absolute time signal. The system is self rectifying, reduces systemic errors, and reduces the data transmission required for system control and operation. The system permits autonomous, asynchronous operation by a subsystem without continuous control by a central controller as a function of time, and can interactively respond to events without intervention from the central controller.

Abstract: A portable system for drilling geophysical shot holes in mixed geologic conditions. The system includes a drill for creating a shot hole in unconsolidated soil and for maintaining gauge in mixed geologic conditions. An explosive projectile for contacting hard rock is directed by a shot barrel, and a compressed air device removes residue from the shot hole. A controller can selectively discharge explosive projectiles when the drill bit encounters hard rock, and can cease the discharge of explosive projectiles when the drill bit encounters unconsolidated soil below hard rock. The system is particularly useful in preparing a slender shot hole in remote conditions restricting the mobility of drilling equipment, and in mixed geologic conditions comprising unconsolidated soils and hard rock aggregates or base rock.

Abstract: A seismic acoustic signal source includes a hull that has a wetted surface in contact with a body of water. When underway, the draft of the hull is substantially zero. An acoustic signal generator is provided with a linear actuator that is resiliently mounted in the hull. The linear actuator is acoustically coupled to the hull bottom such that when the signal generator is activated, the hull radiates an acoustic wavefield into the water.

Abstract: An apparatus for generating signals and energy for transmission to a large mass. The apparatus incorporates a pulsed generator such as a compensated pulsed alternator for storing and for discharging large amounts of energy in a controlled manner for transmission through a vibrator or similar electromechanical device. In the field of seismic exploration, the apparatus discharges seismic source energy into a land mass or water to generate seismic waves which are reflected from the interface between subsurface geologic formations. The pulsed generator permits the seismic source energy to be discharged in a controlled manner to shape the energy signal, and permits large quantities of energy to be discharged to increase the penetration depth and strength of the reflected signals.

Abstract: A packer for sealing a space downhole in a well. The packer includes a deformable sheath having a body and first and second ends for defining an interior volume proximate to a tool surface. A material located within the interior volume is deformable, when the sheath second end is moved toward the sheath first end, to move the deformable sheath into the downhole space. The sheath can function as a sealing element or a backup element, and can be applied to different structures and tool configurations downhole in a wellbore. One or more deformation surfaces can selectively contact the sheath body to shape the deformation of the sheath body during the setting process.

Abstract: A well treatment tool is installed along the sucker rod string of a well, within the surrounding production tube string. The tool provides for the distribution of a treatment fluid (solvent, etc.) within the fluid being pumped or flowing from the well. The tool receives treatment fluid through the hollow sucker rod string, and distributes the fluid through a valve which is set at a predetermined pressure. When the treatment fluid pumped down the sucker rod string from the surface exceeds the predetermined opening pressure of the valve, the treatment fluid is distributed into the production tube string through one or more passages in the tool. The present tool may be used simultaneously with well production, with fluid (oil, etc.) rising up the production tube string, carrying the treatment fluid therewith. The treatment fluid is thus distributed throughout the local fluid processing system, including pipelines from the well, any initial treatment operations, and any storage tanks.

Abstract: An automated quality control system for processing geophysical seismic data and positioning data from a marine navigation system. The invention includes a prospect data logger in communication with system components for accessing the seismic data, for coordinating seismic data processing, and for identifying and storing attribute data relevant to the seismic data and the positioning data. The prospect data logger is capable of storing data in a programmed format, and can be engaged with a display for illustrating data accessible to the prospect data logger. The prospect data logger is capable of automatically performing quality control functions such as checking seismic data and positioning data, of verifying the format of merged seismic and positioning data, of generating a command for indicating an event or for controlling another system component. The prospect data logger can verify storage tape quality immediately after data is inputted, and a record of events can be generated.

Abstract: An apparatus and method for retaining shaped charges. A foam core having charge carrying recesses can be constructed from a single piece or from multiple sections. Shaped charges are insertable within the foam core recesses so that the shaped charges are proximate to a detonator cord positioned inside or outside of the foam core. The foam core assembly holding the detonator cord and shaped charges is inserted into a housing such as a cylindrical tubing to construct the perforating gun. A seal isolates the shaped charges from pressurized well fluids. The housing can be attached to a firing head and lowered to the desired depth in a well casing. Additional foam sections can be added to modify the number and orientation of the shaped charges. The invention is particulaly useful with thin housing material and substantially reduces the manufacturing cost of perforating guns.

Abstract: A shaped charge for efficiently transferring energy from an explosive material to generate a deep penetrating jet. The shaped charge liner is formed with a hemispherical first section combined with an elongated second section. The liner second section can be formed as a truncated cone, trumpet, or other shape. The hemispherical first section collapses to generate a high velocity jet portion, and the second section collapses to generate an elongated, deep penetrating jet portion which follows the higher velocity jet portion.

Abstract: An apparatus and method for evaluating formation damage proximate to the surface of a rock. The invention is applicable to surface tests and to tests downhole in a borehole. A first hollow probe sealingly contacts the rock surface to define a first surface area, and the pressure within the hollow probe is decreased to monitor resulting pressure changes. A second hollow probe contacts the rock surface to define a second surface area having a different size than the first surface area, and the pressure within the hollow second probe is decreased to monitor resulting pressure changes. Differences in the observed pressure changes can be analyzed to evaluate formation damage to the rock surface and near surface. In particular, the thickness of formation damage, and permeability losses caused by such damage, can be assessed. Alternatively, fluid pressure can be injected into the first and second volumes to evaluate the subsequent pressure reduction.

Abstract: An apparatus for generating a large perforation in a target such as a wellbore casing. A liner is positioned within a charge case lowered into a well. An explosive material is initiated to collapse the liner to form a material penetrating jet. A spoiler is positioned proximate to the liner to defocus the liner collapse. The spoiler forms a hollow center in the material penetrating jet and concentrates the energy of the jet into a large annular ring for penetrating the target. The spoiler can comprise a passive spoiler which blocks the full collapse of the liner, or can comprise an active spoiler incorporating a high explosive or an elastic material for counteracting the liner collapse. The spoilers can be spherical, cylindrical, tapered, or another shape to modify the configuration and performance of the material penetrating jet, and a spacer can retain a spoiler in a selected orientation relative to the liner.

Abstract: A system for evaluating multiphase flow of a fluid downhole in a borehole. Dielectric permittivity electrodes generate a capacitance output signal through the fluid, and conductivity electrodes generate a conductivity output signal through the fluid. The electrodes are powered with an AC generator operating at the same or different frequencies. The capacitance and conductivity output signals can be alternately generated by operating a controller, and such signals can be combined with a multiplexer engaged with the controller. The signal can be processed downhole or can be transmitted to a receiver positioned at the well surface for processing and interpretation of the multiphase data.

Abstract: An apparatus and method for detecting the location of subsurface markers in a formation proximate to a borehole. The apparatus includes marker detectors in a housing having at least two housing sections attached in an initial orientation. The distance between the detectors is measured under controlled conditions with a calibration bar. The initial attached orientation between the housing sections is identified with a calibrator, and deviations from the initial attached orientation are identified by the calibrator after the housing sections are detached and reattached. The calibrator permits well site corrections to be made to the housing sections without recalibration. Gauges permit corrections for temperature and pressure fluctuations, and the corrected distances between the housing detectors is computed.

Abstract: An adjustable valve for controlling fluid flow between an inlet and an outlet in a valve. A compressed spring biases a valve member against the valve inlet to prevent fluid flow until the fluid pressure reaches a certain level. One end of the spring contacts a hydraulic plunger which is moved with a hydraulic fluid. The hydraulic fluid pressure can be raised to increase the spring force acting against the valve element, and the hydraulic fluid pressure can be reduced to decrease the spring force acting against the valve element. The flow rate at the valve outlet can be monitored, and flow rate signals can be transmitted to a controller for adjusting the hydraulic fluid pressure in response to the flow rate detected.

Abstract: An improved check valve for selectively controlling the flow of fluid through a valve seat. A spring biases a plunger against the valve seat when the fluid is stationary. Movement of the fluid pushes the valve plunger against the spring to open the aperture of the valve seat. An actuator selectively exerts a force against the plunger to close the plunger against the valve seat. In one embodiment of the invention, the actuator directs a pressurized fluid against a second end of the plunger, and a seal prevents leakage of such fluid toward the plunger first end in contact with the valve seat. A cavity between the seal and the plunger first end can be vented to the atmosphere to maintain the pressure differential created by the pressurized fluid against the plunger second end.

Abstract: An apparatus for generating a large perforation in a target such as a wellbore casing. A recess in a housing has a closed end and an open end facing the target. A shaped liner in the recess has an apex facing the recess open end, and has a base end facing the closed end of the recess. The shaped liner defines an interior volume filled with explosive material. The explosive material is detonated and expands the liner against the recess wall and forms a perforating jet which moves toward the recess open end. If the recess open end is circular, the perforating jet exits the recess as an annular jet which impacts the target and cuts a plug section from the target. The penetrating power of the jet is confined to the annular cutting area instead of being focused into a conventional jet shape. Multiple shaped liners can be placed in the recess, and the shape of the perforating jet can be modified by the liner shape and recess dimensions.

Abstract: A well perforating apparatus for generating a plurality of material perforating jets. A base has a plurality of recesses or apertures, and a liner is proximate to the base and is indented into each recess or aperture. Explosive charges contact the indented surfaces of the liner to form multiple shaped charges. A detonator activates the explosive material to collapse the liner segments proximate to the explosive charges and to generate a plurality of perforating jets. In one embodiment of the invention, the base initially comprises a planar material that can be formed into a geometric shape for insertion into a cylindrical housing or wellbore. The invention substantially reduces manufacturing costs and is especially useful in permitting a high density shot pattern to be generated by the perforating jets.

Abstract: A firing head for actuating an explosive charge in a perforating gun. A firing pin is positioned within the firing head housing to actuate a booster charge leading to the perforating gun. The firing pin can be actuated by mechanical techniques, by controlling the differential pressure between the housing pressure and the well pressure, and by controlling the absolute fluid pressure inside the housing. A release pin initially secures the firing pin, and the release pin can be mechanically actuated. The release pin is also releasably engaged with a differential piston that communicates with the well pressure through a port in the firing head housing. Increases in the housing fluid pressure moves the piston and attached release pin to release the firing pin into contact with the booster charge. Alternatively, the port can be plugged to permit absolute pressure actuation of the firing pin.

Abstract: An improved shaped charge for generating a jet. A lens shaped waveshaper is positioned within the explosive material of a shaped charge to modify the shape of the divergent detonation wave into a planar wave or a converging wave. The waveshaper is formed with a low sound speed material having a high index of refraction. By reshaping the detonation wave, the acceleration of the shaped charge liner is increased, and the penetration depth and hole size of the jet can be increased. The shaped charge operates more efficiently, thereby requiring less explosive material than a conventional shaped charge.

Abstract: A method and apparatus for aligning a component with an underwater receptacle is disclosed. The component is attached to one end of a swing arm having a hook attached to the other end. The swing arm is lowered in the water until the hook engages a pivot attached to an underwater base at a selected distance from the receptacle. Following such contact, the component is lowered in an arcuate path defined by the rotation of the swing arm about the pivot until the component is aligned with the receptacle. In another embodiment of the invention, a stop is attached to a vertical guidepost at a selected distance from the receptacle and a guidepost engaging hook pivots to lower the component into alignment with the receptacle.