Marathon Oil Company

Wayne O Roszelle

Mark A Plummer

Gary R Cook

Eric B Phelps

Donald E Schroeder, Jr

Disclosed is a system wherein the compensation for temperature effects on a pressure measurement gauge are accomplished by processing the raw pressure measurement signal from the gauge through a linear differential equation to produce a thermally compensated measurement. The linear differential equation expresses the thermally compensated pressure determination as a relation between a derivative of temperature and a derivative of pressure error. The linear differential equation contains several coefficients having constant values, and these constant values are computed by calibrating the pressure gauge in a pressure tank having a known pressure and temperature. When the gauge is later placed in an oil or gas well, the coefficient values are used to obtain the corrected measured pressure from the raw measured pressure received from the gauge.

Transient temperature compensation for pressure gauges

Disclosed is a system wherein the compensation for temperature effects on a pressure measurement gauge are accomplished by processing the raw pressure measurement signal from the gauge through an equation to produce a thermally compensated measurement. The equation expresses the thermally compensated pressure determination as a relation between a derivative of temperature and temperature. When the gauge is placed in an oil or gas well, the equation is used to obtain the corrected measured pressure from the raw measured pressure received from the gauge and the temperature measured adjacent to the gauge.

Transient temperature compensation for pressure gauges using an impulse

Disclosed is a system wherein the compensation for temperature effects on a pressure measurement gauge are accomplished by processing the raw pressure measurement signal from the gauge through an equation to produce a thermally compensated measurement. The equation expresses the thermally compensated pressure determination as a relation between a derivative of temperature and temperature. When the gauge is placed in an oil or gas well, the equation is used to obtain a correction for the measured pressure from the temperature measured adjacent to the pressure gauge.

Transient temperature compensation for pressure gauges using discrete

Flooding of a subterranean formation with micellar dispersions containing petroleum sulfonates obtained by sulfonating whole or topped crude oil is improved through the use of a micellar dispersion of a predetermined viscosity containing an amount of cosurfactant in excess of that required to cause the micellar dispersion to have the highest viscosity possible for the particular micellar dispersion with the particular cosurfactant used. Preferably, the cosurfactant is an alcohol and the cosurfactant concentration is sufficiently high to control the micellar dispersion to have a predetermined mobility when injected into a hydrocarbon-bearing formation.

Flooding with micellar dispersions containing petroleum sulfonates

Improved oil recovery is realized by flooding oil-bearing subterranean formations with an aqueous mixture, preferably a micellar dispersion, comprised of at least two different petroleum sulfonates, the sulfonates have an average equivalent weight within the range of about 390-450, and have an aliphatic to aromatic proton (A/AP) ratio within the range of 4-20 moles per mole but the two sulfonates have a difference in their respective A/AP ratio of at least 2.5 moles per mole.

Sulfonate blends useful for improved oil recovery

Improved oil recovery by flooding subterranean formations with micellar dispersions; comprised of hydrocarbon, water, cosurfactant, electrolyte, and petroleum sulfonate obtained by sulfonating whole or topped crude oil; is obtained by incorporating within the micellar dispersion about 1.5 to about 4.5 wt. % of active sulfonate groups (e.g. --SO.sub.3 NH.sub.4 or --SO.sub.3 Na) which are attached to the petroleum sulfonate. The micellar dispersions of this invention contain an amount of cosurfactant in excess of the amount required to produce a viscosity maximum with the particular micellar dispersion.

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Littleton, CO, United States of America

Wayne O Roszelle