Abstract: An oil and gas well casing inspection tool is disclosed. The casing inspection tool comprises a body; inner and outer contact rollers extending from the body; means for generating a current between the outer contacts; and means for measuring a potential difference between the inner contacts. To enhance the accuracy of the device, capacitance is used downhole to increase the amount of current that can be supplied to the casing. Leaf springs engage the contact rollers to maintain a clean connection between the body and the casing. Signal coders and decoders are also disclosed.

Abstract: The Removable Bottom Founded Structure (RBFS) is an offshore platform for petroleum drilling and producing operations intended for deployment in waters with severe weather and iceberg conditions. It is a two-part structure comprising (1) a platform which is made up of a deck structure, multiple columns and braces; and (2) a reinforced concrete subbase that rests on the sea floor and upon which the platform is founded. The structure is normally held down by gravity for standard platform operations, but during the deballasting procedure due to an iceberg emergency a hold-down system is employed to keep the platform on the subbase until full deballasting is achieved. The system that is used to hold the platform down onto the subbase is located where the platform meets the subbase. It operates on the principle of hydrostatics. On the underside of the columns there are multiple chambers which may be evacuated by pumping and which are vented to the outside atmosphere.

Abstract: A punch tool is disclosed for puncturing the walls of heat exchanger tubes when they become worn in order that the tubes may be repaired. Said tool comprises a hardened, longitudinally drilled, steel rod that is able to fit within the heat exchanger tube. A piston with a cutting bit is fit within a milled slot that communicates with the longitudinally drilled hole of the hardened rod. Once the tool is inserted into a tube to be repaired hydraulic pressure is applied and the piston is forced outward thereby puncturing the tube.

Abstract: A method of inhibiting the dissolution of the gravel pack and/or the erosion of silicate-containing formations subjected to steam-enhanced oil recovery processes. The method includes the addition of CO.sub.2 into the residual liquid phase of the steam, prior to injection down the well bore, to reduce the pH to form about pH 5 to about pH 9.

Abstract: The present invention is a method and apparatus for injecting compressible fluids into multiple zones of a hydrocarbon bearing formation, in particular injecting compressible fluid at a predetermined, constant rate into multiple zones through a single tubing string. Producing zones are packed off and limited entry outlets are installed on the injection tubing string at each producing zone. Injection pressure is maintained and limited entry outlets are designed and sized such that the compressible fluid reaches sonic flow through the outlets so that the flow rate no longer responds to changes in downstream pressures.

Abstract: A method and apparatus for a barbed anchor pile is described in which a pile, having horizontally placed barbs, is driven into the seafloor. Once it is buried to a predetermined depth, the barbs are spread outward into the surrounding soil to ensure that the pile will not be pulled out by uplift loads.

Abstract: The present invention provides a method and apparatus for obtaining liquid samples from a system which is under pressure or vacuum.

Abstract: The present invention indicates that in exploration of permafrost regions of the world for oil and gas accumulations, flexure noise can be attenuated by careful placement of the vibratory source vis-a-vis the receiver array during collection of the Vibroseis.RTM.-type data. If the explorationist adopts a survey strategy in which the vibratory source is separated from the receiver array by a pressure ridge or its equivalent over the ice formation of the region under survey, then - surprisingly - the seismic reflection signals can be easily collected and displayed. Result: continuity of events from onshore reflectors can be easily followed offshore through the transition zone into deeper sea ice regions. He is aided in formulating his exploration strategy by the use of aerial and/or radar photographs or LANDSAT unmanned satellite data for mapping the pressure ridges of the area under survey.

Abstract: The present invention indicates that in exploration of permafrost regions of the world for oil and gas accumulations, flexure noise can be attenuated by careful placement of the vibratory source vis-a-vis the receiver array during collection of the Vibroseis.RTM.-type data. It has been surprisingly found that if the explorationist adopts a survey strategy in which the vibratory source is separated from the receiver array by a pressure ridge or its equivalent over the ice formation of the region under survey, then the seismic reflection signals can be easily collected and displayed. Result: continuity of events from onshore reflectors can be easily followed offshore through the transition zone into deeper sea ice regions.

Abstract: This invention relates to a method of increasing resolution of high-intensity amplitude events in seismic records provided by common midpoint collection methods (CMP) wherein nonsymmetrical travel paths of incident and reflected rays of the generated conventional waves are taken into account prior to trace stacking irrespective of dip or depth of the target reflector. In accordance with the invention, the converted phases of the conventional seismic wave, are processed as to define a series of common reflection point (CRP) coordinates each associated with a gather of converted traces as if a source associated with a given corrected trace was placed at each CRP and activated followed immediately by the relocation of a detector at the CRP and the reception of converted phases of the generated wave comprising the trace.

Abstract: By using wave tracking rather than a downward continuation concept, two sets of elastic wave fields (one generated by a seismic source, the other recorded by multicomponent geophones) are migrated separately and are then imaged. The process is repeated for common shot gathers, and then the images (associated with each common midpoint gather), are stacked.As a consequence of wave tracking, migration operations are preferably performed in the time domain using finite difference discretization equations involving vector properties of the fields but without having to reduce the latter to one-way wave equations.

Abstract: The present invention relates to a hard hat which may be collapsed and easily stored when not in use. The hat uses a brim as a structural support, multiple curved segments and means for locking the segments into place. The multiple curved segments have raised and lowered portions, decreasing radii, and a common pivot point on the sides of the brim. In the collapsed position all the segments are stacked on one side of the brim, but when the hat is to be extended, the first curved segment is rotated about the common axis. As it is rotated a lowered portion on the back inner surface of the segment engages a raised portion on the front outer face of the next segment and it is drawn (as are the remaining segment) along with the first segment. Once the first segment has reached its position on the further side of the brim, the first segment is then locked into place and the hat is complete.

Abstract: The disclosed invention is a method of seismic exploration using non-impulsive vibratory sources activated by filtered stationary, Gaussian codes. The method adds a distortion-free quality to the full-waveform seismic records.

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. The sensor includes a reed switch mechanically imbedded in a support sleeve of a custom safety sub attached to the outer core barrel and electrically actuated by an adjacently positioned signature magnet fitted to the inner barrel to connect a power source uphole from the core barrels with a driver valve of a mud pulser system.During coring, circumferential passage of the reed switch adjacent to the signature magnet (during rotation of the outer core barrel to generate a core), allows the power source to periodically activate the valve driver to produce a series of mud pulses of constant repetition rate. But with the occurrence of rotation of the inner core barrel irregular repetition rates are produced at uphole indicating equipment.

Abstract: The disclosed invention is a method of seismic exploration using non-impulsive vibratory sources activated by stationary, Gaussian codes in urban areas. The method adds a distortion-free quality to the full-waveform seismic records.

Abstract: The present invention provides for on-site capture of carbonaceous gas at sea, for isotopic examination. A capture box is utilized to provide trapping, stripping and combustion of a gas stream to permit methane analysis.

Abstract: The present invention relates to a water detection subassembly and method for forming same, for use in association with water detection system operating within a digital computing center. The subassembly includes a perforated protective semi-circular shield fitted about a fabric mesh supporting copper conductors connected to a low voltage source. The perforations of the shield are formed into two distinct patterns: The first series comprises sets of openings adjacent to the apex of the shield and periodically spaced therealong. Each opening has a common arcuate length L, a width W, and an internal spacing S and, more importantly, is of sufficient dimension to allow easy entry of aerosol mixtures of air and water droplets originating from above the shield.

Abstract: The disclosed invention is a method of seismic exploration using non-impulsive vibratory sources activated by stationary, Gaussian codes in a wellbore environment. The method adds a distortion-free quality to the full-waveform seismic records.

Abstract: This invention relates to a method of increasing resolution of high-intensity amplitude events in seismic records provided by common midpoint collection methods (CMP) wherein nonsymmetrical travel paths of incident and reflected rays of the generated conventional waves are taken into account prior to trace stacking due to the dip and depth of the target reflector.

Abstract: This invention relates to a method of increasing resolution of high-intensity amplitude events in seismic records provided by common midpoint collection methods (CMP) wherein nonsymmetrical travel paths of incident and reflected rays of the generated conventional waves (due to dip and depth) are taken into account prior to trace stacking.