Showing papers by "Mobil published in 1994"
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TL;DR: The molecular sieve MCM-22 contains structural features previously unobserved in this class of materials, including an unusual -T-O-T- chain that passes through the center of a modified dodecasil-1H cage.
Abstract: The molecular sieve MCM-22 contains structural features previously unobserved in this class of materials. Its framework topology, derived from high-resolution electron micrographs and refined with synchrotron x-ray diffraction powder data, contains two independent pore systems, both of which are accessed through rings composed of ten tetrahedral (T) atoms (such as Si, Al, and B). One of these pore systems is defined by two-dimensional, sinusoidal channels. The other consists of large supercages whose inner free diameter, 7.1 angstroms, is defined by 12 T-O species (12-rings) and whose inner height is 18.2 angstroms. These coexisting pore systems may provide opportunities for a wide variety of catalytic applications in the petrochemical and refining industries. Another structural feature is an unusual -T-O-T- chain that passes through the center of a modified dodecasil-1H [4(3)5(6)6(3)] cage.
764 citations
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19 Apr 1994TL;DR: In this paper, a method for improving hydrocarbon flow from a consolidated, tight reservoir rock having authigenic clay cementation is proposed, which includes thermally heating the reservoir rock in-situ surrounding a production well to change the mode of occurrence of clay cements within the rock so as to enhance reservoir permeability and carry out rapid flowback into the production well.
Abstract: A method for improving hydrocarbon flow from a consolidated, tight reservoir rock having authigenic clay cementation includes thermally heating the reservoir rock in-situ surrounding a production well to change the mode of occurrence of clay cements within the rock so as to enhance reservoir permeability and carrying out rapid flowback into the production well.
268 citations
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21 Mar 1994TL;DR: In this paper, a method for recovering hydrocarbons (e.g. oil) from a low permeability subterranean reservoir of the type comprised primarily of diatomite is presented.
Abstract: A method for recovering hydrocarbons (e.g. oil) from a low permeability subterranean reservoir of the type comprised primarily of diatomite. A first slug or volume of a heated fluid (e.g. 60% quality steam) is injected into the reservoir at a pressure greater than the fracturing pressure of the reservoir. The well is then shut in and the reservoir is allowed to soak for a prescribed period (e.g. 10 days or more) to allow the oil to displaced by the steam into the fractures by imbibition. The well is then produced until the production rate drops below an economical level. A second slug of steam is then injected and the cycles are repeated with the volume of each subsequent slug of steam being progressively smaller that the one before it (i.e. about 80%) and the respective soak period being increased by about 20% over that of the previous cycle.
259 citations
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TL;DR: The continental margin off the Niger Delta is undergoing deformation by gravity tectonism caused by rapid seaward sediment progradation, and three regional structural styles are recognized: (1) an upper extensional zone of listric growth faults beneath the outer shelf; (2) a translational zone of diapirs and shale ridges beneath the upper slope; and (3) a lower compressional zone of imbricated thrust structures (toe thrusts) beneath the lower slope and rise as mentioned in this paper.
258 citations
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19 Apr 1994TL;DR: In this paper, a support containing methylalumoxane and derivatives thereof is described, which is formed by an incipient impregnation technique, and the most preferred support is silica.
Abstract: A support containing methylalumoxane and derivatives thereof is described which is formed by an incipient impregnation technique. The most preferred support is silica. Incipient impregnation in accordance with the invention provides a supported alumoxane, methylalumoxane, which substantially eliminates the problem of fluidized bed reactor fouling when methylalumoxane is introduced into the reactor during its operation. In accordance with the invention, the process comprises providing methylalumoxane activated metallocene compound in particulate form as catalysts in fluidized bed gas phase operation.
201 citations
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TL;DR: In this article, a regional sedimentological study of Cretaceous sequences in the Mid-Norway region (Norwegian Sea) and in the Agat region (Agat field area, northern North Sea) reveals that these sequences were predominantly deposited in an upper continental slope environment by slumps and debris flows.
Abstract: A regional sedimentological study of Cretaceous sequences in the Mid-Norway region (Norwegian Sea) and in the Agat region (Agat field area, northern North Sea) reveals that these sequences were predominantly deposited in an upper continental slope environment by slumps and debris flows. Examination of nearly 500 m of core from 14 wells shows eight distinct lithofacies: facies 1 (contorted conglomerate and pebbly sandstone) represents deposits of sandy slumps and debris flows, possibly in a channel setting; facies 2 (contorted sandstone) is the most widespread and is the product of sandy slumps and debris flows; facies 3 (contorted mudstone) indicates deposition from muddy slumps and debris flows; facies 4 (rippled sandstone) suggests bottom-current reworking; facies 5 (gr ded sandstone) represents turbidity-current deposits and is very rare; facies 6 (laminated mudstone) is a product of pelagic or hemipelagic deposition; facies 7 (cross-bedded sandstone) is indicative of tidal processes; and facies 8 (laminated sandstone) represents delta-front and shelf deposits. These facies and their association suggest a shelf-edge delta to upper slope environment of deposition. Existing core data document deltaic facies only in the Mid-Norway region. The proposed shelf-edge delta and upper slope model has important implications for sand distribution. (1) This model provides an alternative to the conventional submarine-fan model previously applied to these sequences. (2) Although slump and debris-flow emplaced sands are usually discontinuous and unpredictable, highly amalgamated slump and debris-flow sands may develop thick reservoirs. (3) By using the Eocene Frigg Formation as an analog, it is predicted that externally mounded seismic facies in the study area may be composed of sandy slumps and debris flows.
140 citations
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TL;DR: The path of seawater 87 Sr 86 Sr during the Mississippian, Pennsylvanian and Permian is estimated based on 228 analyses as discussed by the authors, which are largely from the southern interior of the U.S.A., where rocks of this age are widely exposed.
123 citations
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TL;DR: A suite of 40 Pennsylvanian and Permian shelf limestones from Kansas and Oklahoma has been analyzed for major and trace elements and for C, O and Sr isotopes.
116 citations
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TL;DR: In this article, the authors present a review of basic seismic attributes, their recently introduced derivatives and their expected significance and also classify them with respect to their computation and their end use.
Abstract: Since their introduction in early 1970`s seismic attributes have become one of the most commonly used and powerful interpretation tools. In earlier applications they were considered as a management display tool. This view has changed rapidly as their use in interpretation expanded. Results were analyzed in a qualitative manner. Recently, as evidenced from increasing number of papers, attribute use finally became more quantitative through calibration with well bore measurements. In this paper the authors will present a review of basic attributes, their recently introduced derivatives and their expected significance. They will also classify them with respect to their computation and their end use. They define all seismically driven parameters as the Seismic Attributes. They can be velocity, amplitude, rate of change of any of them with respect to time or space and so on. They can be computed from pre-stack or post stack data sets. Some of the attributes computed from complex traces such as envelope, phase and etc. correspond to the various measurements of the propagating wave-front. They will call those the physical Attributes. These attributes may be used for prediction or extrapolation of lithological or reservoir characteristics. Others are computed from the reflection configurations and continuity. They willmore » call these Geometric Attributes. These are used in structural and stratigraphic interpretation. In this paper they will confine themselves to the classification and definition of the attributes and their possible uses. They will give examples from different geological settings.« less
112 citations
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TL;DR: Carbon isotopic compositions of saturated hydrocarbons, aromatic hydrocarotene, NSO (resin), and asphaltene fractions of vein-forming gilsonites (Cowboy, Bonanza, Independence, Wagonhound and Harrison veins) in the NE Uinta Basin, Utah, are all similar and isotopically resemble Mahogany Zone shale extracts of the Green River Formation as discussed by the authors.
112 citations
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TL;DR: In this paper, seismic reflection data reveals that the Seattle basin (Washington) is markedly asymmetric and consists of ∼9-10 km of Eocene and younger deposits, and that dextral offset on the Puget fault south-east of Seattle stepped eastward, and the Seattle fault began as a restraining transfer zone.
Abstract: Analysis of seismic reflection data reveals that the Seattle basin (Washington) is markedly asymmetric and consists of ∼9-10 km of Eocene and younger deposits. The basin began as a discrete geologic element in the late Eocene (∼40 Ma), the result of a reorganization in regional fault geometry and kinematics. In this reorganization, dextral offset on the Puget fault south- east of Seattle stepped eastward, and the Seattle fault began as a restraining transfer zone. North-vergent reverse or thrust faulting on the Seattle fault forced flexural subsidence in the Seattle basin to the north. Offset on the Seattle fault and subsidence of the Seattle basin have continued to the present.
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TL;DR: In this paper, a comparison of hydraulic-fracture models run using test data from the GRI Staged Field Experiment No. 3 is presented, showing the differences in length, height, width, pressure and efficiency.
Abstract: This study is a comparison of hydraulic-fracture models run using test data from the GRI Staged Field Experiment No. 3. Models compared include 2-D, pseudo-3-D, and 3-D codes, run on up to eight different cases. Documented in this comparison are the differences in length, height, width, pressure and efficiency. The purpose of this study is to provide the completions engineer a practical comparison of the available models so that rational decisions can be made about which model(s) is optimal for a given application.
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07 Jul 1994TL;DR: In this article, a process for the treatment of exhaust gas, which process uses a specially prepared catalyst composition, for the selective catalytic reduction of NOx contained in the exhaust gas.
Abstract: There is presented a process for the treatment of exhaust gas, which process uses a specially prepared catalyst composition, for the selective catalytic reduction of NOx contained in the exhaust gas An embodiment of the process of this invention comprises a catalytic stage to selectively catalytically reduce NOx over a catalyst composition comprising a molecular sieve that has been treated with a metal in a way effective to maximize metal dispersion The catalyst of this invention typically comprises a silica, titania, or zirconia binder, eg a binder including a high molecular weight, hydroxyl functional silicone resin The catalyst of this invention may be formed into a desired shape, eg, by extrusion, and finished in a humidified atmosphere after forming
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TL;DR: In this article, the authors formulated a new model based on the efficiency with which water-bearing rocks conduct electric currents as determined by the conducting phase geometry of a sedimentary rock.
Abstract: Knowledge of the way pore geometry affects the conductivity of rocks is important for the evaluation of sedimentary rocks for hydrocarbon potential. Virtually all formation evaluation from logs, however, uses the empirical Archie equation that has never been given a satisfactory physical basis. As an alternative, we have formulated a new model based on the efficiency with which water-bearing rocks conduct electric currents as determined by the conducting phase geometry. Electric current densities are not uniform throughout the conducting phase in the pore system of a rock. Numerical model studies show high current density in pore throats and low current density in nearly stagnant volumes in isolated parts of the pore system. The electrical efficiency of a rock is the ratio of the average power developed in all water-bearing parts of the pore system to the power developed in a straight tube with the same length and water volume as the rock. It is inherently independent of the bulk volume of water in the rock and determined only by the nonuniform current distribution caused by pore geometry and hydrocarbons in the pore system. Electrical efficiency can be calculated a priori given the geometrical distribution of the conducting phase. Empirical relationships between electrical efficiency and water content can be used to calculate hydrocarbon saturations from log data.
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01 Dec 1994TL;DR: In this paper, a specific consolidating solution comprised of an allyl monomer and an initiator is injected into the formation where it is allowed to set at an elevated temperature to harden and form a permeable, consolidated mass.
Abstract: A method for consolidating a subterranean formation to control the production of particulates therefrom. A specific consolidating solution comprised of an allyl monomer and an initiator is injected into the formation where it is allowed to set at an elevated temperature to harden and form a permeable, consolidated mass. The allyl monomer is an allyl ester selected from the group of diallyl orthophthalate, diallyl isophthalate, diallyl terephthalate, diallyl benzenephosphonate, diethylene glycol bis (allyl carbonate) and other known allyl monomers and the initiator is preferably a peroxy compound (e.g. benzoyl peroxide, diisopropyl peroxydicarbonate, etc.) or an azo compound (e.g. 4,4'-azobis(4-cyanovaleric acid). A diluent such as an alcohol (e.g. isopropyl alcohol or isobutyl alcohol) or a mutual solvent (e.g. ethylene glycol monobutyl ether, diacetin, triacetin, acetone, etc.) and a coupling agent (e.g. an organofunctional silane) may be added if needed.
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15 Sep 1994TL;DR: In this article, a method for selectivating a zeolite, such as ZSM-5, which may result in functionalization of the zeolites with at least one organosiliceous group of the formula, SiRn (OX)4-n, where R is at least a hydrocarbyl group, n is 1 or 2 and X is Si or H.
Abstract: There is provided a method for selectivating a zeolite, such as ZSM-5 which may result in functionalization of the zeolite with at least one organosiliceous group of the formula, SiRn (OX)4-n, where R is at least one hydrocarbyl group, n is 1 or 2 and X is Si or H. This selectivation method involves vapor phase treatment of a zeolite with an organosilicon compound having at least 2 silicon atoms. This organosilicon compound may be a silicone compound, such as hexamethyldisiloxane, or a silane compound such as hexamethyldisilane. This contacting may take place in the presence of hydrogen and an organic carrier. The functionalized zeolites may provide a catalyst which is both highly active and highly selective for converting aromatic hydrocarbons, especially alkylbenzene compounds, to products comprising the para-isomer of dialkylbenzenes. The disproportionation of toluene is an example of such a reaction.
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TL;DR: In this article, the authors use residual salt analysis (RSA) to identify barriers to vertical fluid flow in oil and water legs, which can be used to predict the dynamic behavior of the reservoir later in field life.
Abstract: Fluid composition is a valuable addition to the battery of static'' data available during reservoir appraisal that can be used to predict the dynamic behavior of the reservoir later in field life. This is because fluid data are not truly static; natural fluid mixing is a dynamic process that occurs over a long (geologic) time scale. Oil compositional differences, especially those that parallel changes in density, should be mixed rapidly by convection; their preservation indicates barriers to fluid flow. Water variations, now measurable on conventional core samples by use of residual salt analysis (RSA), help identify barriers to vertical fluid flow in oil and water legs.
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02 May 1994TL;DR: In this article, the zipper is cut apart at the location that is to be the edge of the bag, the ends formed by the cutter moved laterally relative to each other exposing the ends and the slider is inserted over one of the exposed ends.
Abstract: In a continuous bag-making process, the film and zipper track moves intermittently through a bag machine in a continuous stream, so there is no end to the zipper track on which the slider can be inserted. In the present invention, in the intermittent motion-part of the bag machine, the zipper is cut apart at the location that is to be the edge of the bag, the ends formed by the cutter moved laterally relative to each other exposing the ends and the slider is inserted over one of the exposed ends.
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12 Oct 1994TL;DR: A marine riser system which combines rigid (e.g. steel catenary risers) with flexible flowlines is described in this article, in which the steel risers are curved upward through the water in a gentle catenary path to a large, submerged buoy, which is moored to the bottom by tension leg tether lines at a depth below the turbulence zone of the water.
Abstract: A marine riser system which effectively combines rigid (e.g. steel catenary risers) with flexible flowlines. Basically, the steel catenary risers, which are merely the end portion of submerged rigid flowlines, are curved upward through the water in a gentle catenary path to a large, submerged buoy, which, in turn, is moored to the bottom by tension leg tether lines at a depth below the turbulence zone of the water. Flexible flowlines are fluidly connected to the steel catenary risers at the buoy and extend upward through the turbulence zone to the surface.
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TL;DR: In this paper, the authors studied the effect of electrokinetics on the spontaneous potential (SP) log of a single-phase brine streaming potential and showed that the streaming potential is independent of the permeability of the rock.
Abstract: In trying to understand the affect of electrokinetics on the spontaneous potential (SP) log, the focus has generally been on the solid‐brine streaming potential. Within the accuracy of the measurements, the streaming‐potential coupling coefficient is shown to be independent of the permeability of the rock. The solid‐brine streaming potential is of much smaller magnitude than the electrostatic potentials from gas‐liquid and liquid‐liquid flow. Air bubbles were found to increase the streaming potential coupling coefficient by more than two orders of magnitude over the value for single‐phase brine flow. Thus, two‐phase gas‐liquid flow is more likely to have a significant impact on the SP log than is single phase liquid flow. Two‐phase oil‐brine flow may also produce a larger electrokinetic potential than single‐phase flow. The magnitude of the electrokinetic potential caused by oil‐brine flow will depend on the composition of the oil and the brine. Trace materials can have a major impact on the electrokineti...
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TL;DR: In this paper, a consistent data base of reaction pathways, kinetics, and mechanisms for catalytic hydrogenation of one-, two-, three-, and four-fused aromatic ring compounds allowed for correlation of their Langmuir-Hinshelwood-Hougen-Watson (LHHW) rate law parameters with molecular structure.
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31 Aug 1994TL;DR: A polymeric film structure having improved oxygen and moisture barrier characteristics is disclosed in this paper, which includes a polymeric substrate adapted to receive an oxygen barrier on one side thereof and a moisture barrier on the other side of the oxygen barrier.
Abstract: A polymeric film structure having improved oxygen and moisture barrier characteristics is disclosed The structure includes a polymeric substrate adapted to receive an oxygen barrier on one side thereof and a moisture barrier on the other side of the oxygen barrier The oxygen barrier includes polyvinyl alcohol cross-linked with aldehyde containing cross-linking agents in the presence of a catalytic amount of an inorganic acid, preferably sulfuric acid The moisture barrier is a metallized polymeric composite, preferably metallized oriented polypropylene
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28 Apr 1994TL;DR: In this article, a base polymer film, e.g., oriented isotactic polypropylene, is coated with a composition comprising a copolymer of about 65 to 95 wt.% ethylene and about 5 to 35.% acrylic or methacrylic acid.
Abstract: Novel coated films are disclosed wherein a base polymer film, e.g., oriented isotactic polypropylene, is coated with a composition comprising a copolymer of about 65 to 95 wt.% ethylene and about 5 to 35.% of acrylic or methacrylic acid (an 'ethylene copolymer') based on the weight of the polymer in which about 2 to 80 % of the carboxylate groups are neutralized with metal ions from Group Ia, IIa or IIb of the Periodic Table, preferably sodium ions. Preferably the coating also contains microcrystalline wax and fumed silica. The coated films exhibit good low temperature sealing properties accompanied by satisfactory hot tack and resistance of the seals to immersion in water.
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TL;DR: In this paper, the authors used modeling to aid the design and selection of new templates for ZSM-18, and the geometry and charge distribution of these templates were chosen to best fit their estimate of "templating".
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TL;DR: In this article, a technical and economical evaluation of pipeline transportation of hydrogen, natural gas and their mixtures is presented, with particular emphasis on those aspects of pipeline design that bear a direct relevance to the final levelized cost of transmission.
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01 Jan 1994••
TL;DR: This article investigated the genesis and evolution of Peahala Ridge, a modern shoreface-attached sand ridge 1 km 6 km in size and 4-7 m in bathymetric relief, through an integrated sedimentologic and stratigraphic study.
Abstract: We investigated the genesis and evolution of Peahala Ridge, a modern shoreface-attached sand ridge 1 km 6 km in size and 4-7 m in bathymetric relief, through an integrated sedimentologic and stratigraphic study involving vibracoring, box coring, grab samples, high-resolution seismic, paleontology, radiocarbon dating, and oceanographic measurements Near-surface strata of Peahala Ridge include six important stratigraphic units: modern shoreface, upper ridge sand, lower ridge sand, swale/inlet-fill, Middle Holocene back-barrier, and Late Pleistocene strandplain Radiocarbon dating and determination of the stratigraphic relationships indicates that Peahala Ridge formed initially from an ebb-tidal delta associated with a tidal inlet So thwestward migration of the inlet channel, a vector resultant of landward coastal retreat and southerly longshore drift, cut and then filled the swale separating Peahala Ridge from Long Beach Island Following inlet closure, Peahala Ridge developed its present form as a shoreface-attached, shoreline-oblique bathymetric feature Hydrodynamic processes have played a major role in evolution of the ridge, including considerable growth and accretion This combination of long-term (eustatic) and short term (hydrodynamic) factors is the best explanation for the present morphology and internal stratigraphy of Peahala ridge
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22 May 1994TL;DR: In this article, a second order active bandpass filter for a fixed center frequency and a tunable one have been developed in a coplanar line technique using negative resistance circuits and operate in the 1.8 GHz band and have a 3 dB bandwidth of 110 MHz.
Abstract: A second order active bandpass filter for a fixed centre frequency and a tunable one have been developed in a coplanar line technique using negative resistance circuits. These filters operate in the 1.8 GHz band and have a 3 dB bandwidth of 110 MHz. The tuning range of the centre frequency is 200 MHz. Each filter is fabricated on a GaAs substrate and occupies an area of 1.5/spl times/1.6 mm/sup 2/ on the wafer including all biasing elements. >
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01 Jan 1994TL;DR: Fast training algorithms are presented for the training of neural networks used for inversion and classification problems, built upon a previously described technique in which linear equations are solved for the network's output weights.
Abstract: Fast training algorithms are presented for the training of neural networks used for inversion and classification problems. The algorithms build upon a previously described technique in which linear equations are solved for the network's output weights. First, the method is motivated by an analysis of the multilayer perceptron, based on polynomial basis functions. A conjugate gradient solution to the output weight equations is introduced, which works even when the equations are ill‐conditioned. Techniques are described which can be used to improve hidden unit weights. The output weight optimization technique is extended to classification networks, which have nonlinear output unit activations. Neural networks for inversion of surface scatter parameters and classification of sea ice are designed to illustrate the techniques. It is seen that the techniques are significantly faster than back‐propagation.
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28 Feb 1994TL;DR: A low emission diesel fuel suitable for use in underground diesel-engined mining equipment comprises a straight run distillate fuel having an end point not greater than 300 °C (about 660 °F), a cetane number in the range of 55 to 60, a specific gravity not less than 0.83 and an aromatics content of 18 to 30 wt. percent.
Abstract: A low emission diesel fuel suitable for use in underground diesel-engined mining equipment comprises a straight run distillate fuel having an end point not greater than 300 °C (about 660 °F), a cetane number in the range of 55 to 60, a specific gravity not greater than 0.83, a sulfur content not greater than 0.1 wt. percent and an aromatics content of 18 to 30 wt. percent. The T90 of the fuels is typically in the range of 255° to 270 °C (about 490 °F to 525 °F), with an initial boiling point typically in the range of 170° to 190 °C (about 340° to 374 °F). Ten percent points (T10) are typically in the range from about 200° to 220 °C (about 390° to 430 °F). The API gravity of the fuel is at least 38 and is typically in the range of 38 to 42 and the specific gravity is typically in the range of 0.82 to 0.83.