Texaco Inc.

Wayne F Warren

Percy T Cox

Theodore W Nussbaum

Donald L Johnson, Jr

Dan M Arnold

Donald J Dowling

Gregory J Hatton

Albert P Richter

Michael G Durrett

Roland G Riedesel, Jr

Raymond C Hedges

The gas fraction and the slip velocity are proportional to the difference in dielectric readings taken in a vertically upward flowing stream of oil/water/gas and in a vertically downwardly flowing stream of the same mixture. Actual water cuts are obtained by appropriately adjusting the dielectric water cut readings.

Method of standard dielectric water cut measurement with small gas

The present invention is a thin bed resistivity well logging system and method which includes a transmitter transmitting electromagnetic energy into an earth formation, from within a borehole traversing the earth's formation, at a frequency lying within a range of frequencies from 500 kilohertz to 4 megahertz. The system, a portion of which is located in the borehole, determines the true resistivity of a thin strata in accordance with the transmitted electromagnetic energy that has propagated through the earth's formation.

Electromagnetic propagation thin bed resistivity well logging system and

A well logging system and method of the present invention determines the dielectric constant and/or conductivity of earth formations some of which have fluid invasion. The system and method of the present invention includes the transmission of electromagnetic energy into the earth formation from a first location in a borehole in the formations at a frequency which enables the electromagnetic energy to propagate throughout the surrounding earth formations. Electromagnetic energy is received by receivers at three locations in the borehole which are spaced longitudinally from the location of the transmission of the electromagnetic energy. The receivers provide signals representative of the total electromagnetic fields at those locations. The dielectric constant and/or resistivity of the earth formations are determined in accordance with portions of the signals from the three receivers corresponding to secondary electromagnetic fields at the three receiving locations.

Deep penetration well logging system and method

An electromagnetic energy well logging system and method includes transmitting electromagnetic energy substantially at a frequency of 4 MHz into an earth formation from a borehold traversing the earth formation. The true resistivity of an oil-based flushed zone of the earth formation is derived in accordance with the transmitted electromagnetic energy after it is passed through at least a portion of the oil-based flushed zone.

Oil-based flushed zone electromagnetic well logging system and method

A well logging system and method of the present invention determines the dielectric constant and/or conductivity of earth formations some of which have fluid invasion. The system and method of the present invention include the transmission of electromagnetic energy into the earth formations from a first location in a borehole in the formations at a frequency which enables the electromagnetic energy to propagate throughout the surrounding earth formations. Electromagnetic energy is received by receivers at three locations in the borehole which are spaced longitudinally from the location of the transmission of the electromagnetic energy. The receivers provide signals representative of the received electromagnetic energy. The dielectric constant and/or resistivity of the earth formations are determined in accordance with the signals from the three receivers.

Deep penetration well logging sonde

Apparatus for determining the dielectric constant and/or resistivity of earth formations traversed by a borehole includes a transmitter which transmits electromagnetic energy into the earth formation from a first location in the borehole at a frequency which enables the electromagnetic energy to propagate throughout the surrounding earth formations. Receivers receive electromagnetic energy at two locations in the borehole which are spaced longitudinally from the transmitter provide signals representative of the total electromagnetic fields at the receiver locations. Circuitry determines the dielectric constant and/or resistivity of the formations in accordance with a secondary field ratio and a phase difference derived from the signals provided by the receivers.

Secondary field dielectric constant and/or resistivity well logging

Deep penetration well logging system and method using secondary

An improvement to a conventional one transmitter coil-two receiver coil dielectric well logging sonde permits the well logging sonde to have deeper penetration of the earthen formation when measuring dielectric constants. The improvement includes increased spacing between the receiver coils and the transmitter coil and operation of the transmitter coil at a higher power level.

High transmitting power deep penetration well logging sonde

Method of deep penetration well logging using three receivers

A method of determining the permeability of a particular stratum in an earth formation traversed by a borehole includes injecting a liquid into the borehole at a first pressure thereby causing liquid flow into the stratum. A first flow rate of the liquid is determined at the first pressure. The pressure of the liquid being injected into the borehole is then changed to a second pressure level and a second flow rate of the liquid flowing into the stratum is determined at the second pressure. An indication of the permeability of the stratum is then derived in accordance with the two pressures, the two flow rates and known characteristics of the stratum.

In-situ permeability determining method

A well logging tool adapted for use in a borehole traversing an earth formation includes at least one sensor sensing at least one characteristic of the earth formation. Another sensor senses the ambient temperature and provides a corresponding temperature signal. An output circuit provides a temperature compensated output signal corresponding to the sensed characteristic of the earth formation in accordance with the temperature signal and the characteristic signal.

Temperature compensated well logging tool

Oxygen in a borehole fluid in the vicinity of a reference region, such as an earth formation of known fluid permeability, is activated with a logging instrument by being bombarded with neutrons of 14 MEV energy level to form the unstable isotope nitrogen 16 giving rise to gamma radiation. Flow of the activated fluid is then caused by an electrohydraulic flow generator which forms an intense pressure pulse in the fluid. A gamma ray detector in the logging instrument senses the amount of flow of the activated fluid within the borehole in the reference region. The logging instrument is then moved to a formation whose liquid permeability is to be tested. Borehole fluid opposite the formation to be tested is activated by neutron bombardment, again giving rise to gamma radiation, and fluid flow in the formation under test is caused by the electrohydraulic flow generator. The gamma ray detector reading of activated fluid flow in the borehole opposite the formation under test, when compared with the flow reading in the borehole opposite the reference region, is a measure of relative fluid permeability in the formation being tested.

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Houston, TX, United States of America

Wayne F Warren