Abstract: A method and liner assembly for drilling into unstable or depleted formations is provided that maintains control of the wellbore against caving such as where unconsolidated formations are penetrated and/or minimizes fluid losses such as to underpressured formations where differential pressures exist. The method and liner assembly herein includes the provision of a liner having a portion thereof that is drillable so that after setting of the liner, drilling can continue deeper into the unstable formations with minimal damage to the bit used to drill out the liner drillable portion. In one form, the liner has a shoe that includes cutter mounting blades, each having a set of cutters thereon. Relief slots are formed in the blades between cutters so that as the shoe and its blades are being drilled, the drill bit will cut through the slots, releasing the shoe cutters for transport up to the surface by the drilling fluid thereby minimizing damaging contact of the bit with the shoe cutters.

Abstract: A drilling tool for use with a drill string into which drilling fluid is pumped. The tool comprises: a non-rotating housing having stabilizer blades on its outer surface; a rotating mandrel, passing through the housing; extendible blade means for moving the housing relative to a borehole; and a cam mechanism that is carried by at least one of the mandrel and the housing, and that is operated by drill string rotation and the flow of drilling fluid for operating the extendible blade means to move the drill string and steer the drill bit attached hereto.

Abstract: The present invention relates generally to the field of seismic exploration and, in more particular, to methods of quantifying and visualizing structural and stratigraphic features in three dimensions through the use of eigenvector and eigenvalue analyses of a similarity matrix. This invention also relates to the field of seismic attribute generation and the use of seismic attributes derived from similarity matrices to detect the conditions favorable for the origination, migration, accumulation, and presence of hydrocarbons in the subsurface. Additionally, the methods disclosed herein provide a new means for analyzing unstacked seismic data to uncover AVO effects. The invention disclosed herein will be most fully appreciated by those in the seismic interpretation and seismic processing arts.

Abstract: A method, a map and an article of manufacture for the exploration of hydrocarbons. In one embodiment of the invention, the method comprises the steps of: accessing 3D seismic data; dividing the data into an array of relatively small three-dimensional cells; determining in each cell the semblance/similarity, the dip and dip azimuth of the seismic traces contained therein; and displaying dip, dip azimuth and the semblance/similarity of each cell in the form a two-dimensional map. In one embodiment, semblance/similarity is a function of time, the number of seismic traces within the cell, and the apparent dip and apparent dip azimuth of the traces within the cell; the semblance/similarity of a cell is determined by making a plurality of measurements of the semblance/similarity of the traces within the cell and selecting the largest of the measurements.

Abstract: A method and apparatus for the exploration of hydrocarbons comprising the steps of: obtaining a set of seismic signal traces distributed over a predetermined three-dimensional volume of the earth; dividing the three-dimensional volume into a plurality of analysis cells having portions of at least two seismic traces located therein; computing outer products of the seismic traces within each cell; forming the covariance matrix for each cell from these outer products; computing the dominant eigenvalue and the sum of the eigenvalues of the covariance matrix of each cell and computing a seismic attribute from the ratio of the dominant eigenvalue to the sum of the eigenvalues of the covariance matrix of each cell; and forming map of the seismic attributes of selected groups of cells.

Abstract: The present invention is directed generally toward a method of processing seismic data so as to provide improved quantification and visualization of subtle seismic thin bed tuning effects and other sorts of lateral rock discontinuities. A reflection from a thin bed has a characteristic expression in the frequency domain that is indicative of the thickness of the bed: the reflection has a periodic sequence of notches in its amplitude spectrum, said notches being spaced a distance apart that is inversely proportional to the temporal thickness of the thin bed. Further, this characteristic expression may be used to track thin bed reflections through a 3-D volume and estimate their thicknesses and lateral extent. The usefulness of this invention is enhanced by a novel method of frequency domain whitening that emphasizes the geologic information present within the spectrum.

Abstract: A thermal oil recovery process is disclosed for use in a heavy oil reservoir having a plurality of laterally separated, generally vertical wells whose use have left the reservoir characterized by a heated depletion zone, a channel, voidage, or mobility and communication. The process includes the steps of: drilling a well having a horizontal section and an opening therein that is located laterally between at least two of the vertical wells and at a depth within the lower part of the reservoir; injecting a steam through the two vertical wells to establish thermal communication with said horizontal well; and using the combination of steam drive and gravity drainage to recover oil from the reservoir through the horizontal well.

Abstract: The present invention relates generally to method of seismic data processing which provides a superior method of removing or attenuating some forms of seismic noise and can also be used as a basis for seismic attribute analysis and automatic trace editing. In particular, the present invention is directed toward the application of a Very Short-Time Fourier Transform (VSTFT) to seismic data, coupled with a novel approach to organizing and/or displaying the transformed data, so as to provide highly localized frequency analyses of seismic reflection events. The present invention utilizes a very great number of short overlapping Fourier transform windows, together with a Gaussian weight or taper function, to produce a plurality of near single-frequency "sub-band" traces for each seismic trace so analyzed. Although the present invention can be applied to a single seismic trace, it is preferably applied to a collection of seismic traces that are spatially related.

Abstract: An apparatus for the exploration of hydrocarbons by obtaining a set of seismic signal traces distributed over a pre-determined three-dimensional volume of the earth and using a computer to: divide the three-dimensional volume into a plurality of vertically stacked and generally spaced apart horizontal slices; divide each of the slices into a plurality of cells having portions of at least three seismic traces located therein; measure the cross-correlation between one pair of traces lying in one vertical plane to obtain an in-line value and the cross-correlation between another pair of traces lying in another vertical plane to obtain a cross-line value; and combine the in-line value and the cross-line value to obtain one coherency value for each of the cells; and display the coherency values.

Abstract: A method for measuring and using anisotropy in a coal bed sequence. The method includes the steps of: stripping layers where polarization changes are indicated by applying a static shift to components aligned with the slow shear wave polarization direction and applying one half of the static shift to components neither aligned with the slow shear wave polarization direction nor aligned with the fast shear wave polarization direction; obtaining for a coal bed a measure of the amplitude of the envelope of the fast polarization trace; rotating, by about 45 degrees away from a principal direction, the data set for that coal bed; obtaining a measure of the amplitude of the envelope of at least one of the mixed/mismatched polarization traces of that coal bed; and obtaining the ratio of the amplitude of the envelope of the fast polarization trace to the amplitude of the envelope of one mixed/mismatched polarization trace in that coal bed.

Abstract: A method of producing hydrocarbons from a subterranean formation.

Abstract: A method of producing hydrocarbons from a subterranean formation comprising the steps of: forming a well having a horizontal section located between the midpoint and the bottom of the formation and having a raised end; and continuously injecting a fluid through said raised end to induce hydrocarbons to flow towards the horizontal section in response to gravity drainage while continuously producing hydrocarbons through the horizontal section of the well-bore, so that the injection of fluids occurs simultaneously with the production of hydrocarbons.

Abstract: Disclosure is made of an integrated-magnetic apparatus, comprising: winding structure for insulatingly carrying at least two generally flat, laterally offset and spaced apart electrical windings of a power converter around an aperture; a core having a flat exterior face, an interior cavity and an un-gapped core-column that is located within the cavity and that passes through the aperture of the winding structure; flat-sided surface carried by the core and forming an interior chamber that is located adjacent to the flat face of the core and forming a core-column that has a gap and that is located within the chamber; and structure, located around the gapped core-column, for carrying a third electrical winding of the power converter. The first two electrical windings are substantially located within the cavity and are adapted to be transformingly coupled together through the core.

Abstract: A method for processing multi-source multi-component shear wave seismic data. The method comprises the steps of: acquiring four component shear wave seismic data; converting the data into a matrix that is a function of an angles of rotation relative to a reference axis; computing a time independent norm of the elements of the matrix; and finding the angles of rotation where the difference between the sum of the norms of the in-line elements and the sum of the norms of the cross-line elements is maximized.

Abstract: A hole opener comprising: a cylindrical section of pipe; a nose; a plurality of cutting elements that extend radially from the pipe and that produce a lateral force on the hole opener in response to the rotation of the hole opener in the borehole; lower reaction pad means, extending radially from the pipe section to trail behind the cutting elements and located generally below the cutting elements, for continuously contacting the borehole wall during rotation of the hole opener and for receiving reactive forces that are in response to the lateral force; and upper reaction pad means, extending radially from the pipe section to trail behind the cutting elements and located generally above the cutting elements, for continuously contacting the borehole wall during rotation of the hole opener and for receiving reactive forces that are in response to the lateral force.

Abstract: A method for the exploration of hydrocarbons, comprising the steps of: obtaining a set of seismic signal traces distributed over a pre-determined three-dimensional volume of the earth; dividing the three-dimensional volume into a plurality of vertically stacked and generally spaced apart horizontal slices; dividing each of the slices into a plurality of cells having portions of at least three seismic traces located therein; measuring the cross-correlation between one pair of traces lying in one vertical plane to obtain an in-line value and the cross-correlation between another pair of traces lying in another vertical plane to obtain a cross-line value; combining the in-line value and the cross-line value to obtain one coherency value for each of the cells; and displaying the coherency values.

Abstract: In a curve drilling assembly having a mandrel rotatably mounted within a cylindrical sleeve, an apparatus and method of using the apparatus are disclosed for orienting the sleeve of a curve drilling system and for shifting modes of operation of a curve drilling system from a steering mode to a straight drilling mode. The apparatus comprises: a drilling fluid powered blade that is carried by the sleeve for engaging the walls of a curved borehole and inducing counter-clockwise rotation of the sleeve; and a valve, carried within the mandrel, for operating the blade by introducing pressurized drilling fluid from the interior of a drill string connected to the mandrel.

Abstract: A rotary drill bit for drilling a curved subterranean borehole. In one embodiment, the drill bit comprises a side portion, a plurality of cutting elements that produce a lateral force on the drill bit in response to the rotation of the drill bit in the borehole, and bearing means. The bearing means is located on the side portion of the drill bit and contacts the borehole wall during drilling to receive a reactive force that is from the borehole, that is in response to the lateral force and that is directed to a location adjacent to the uphole end of the side portion of the drill bit. The reactive force and the lateral force form a downhole-moment that is about the drill bit and that is opposed by an uphole-moment having a force component that is directed at the flexible joint. The uphole end of the bearing means is located relatively close to the cutting elements such that the magnitude of the downhole-moment and the magnitude of the uphole-moment are minimized.

Abstract: A thermal oil recovery process is disclosed for use in an oil reservoir containing a plurality of laterally separated generally vertical wells that have been used for cyclic steam stimulation and that have left in the reservoir at least one of a heated depletion zone and a channel. The process includes the steps of: drilling a well having a horizontal section and an opening therein that is located laterally between at least two of the vertical wells and at a depth within the lower part of the reservoir; injecting a heated fluid through the two vertical wells to establish thermal communication with said horizontal well; and using steam drive and gravity drainage to recover oil from the reservoir through the horizontal well.

Abstract: A method and system for geophysical exploration including obtaining, processing, displaying and interpreting seismic data. Seismic energy is imparted into the earth'subterranean formation along at least two linear independent lines of action in a seismic survey. At least two linearly independent components of the seismic wave energy imparted along each line of action are detected within the seismic survey. A concord of seismic signals is produced from the seismic wave energy detected for selected combinations of receiver and source locations. An orientation module operates on the concord of the seismic signals so as to generate synthetic concords of seismic signals so as to focus on a particular component of the seismic wave energy in order to infer the geologic characteristics of the earth's subterranean formations.