Chevron Research Company

Chevron Research & Technology Company

Bibhas R De

Michael A Nelson

Russell E Boyer

Paul L Donoho

David E Revus

Kiran K Pande

Dorothy A Keech

A method and apparatus is described for determining petrophysical properties of porous media by the use of light transmission through the media. Specifically, by using a highly collimated light source, preferably a laser, the permeability, grain size, wettability, porosity and clay swelling behavior of a sample can be determined on the scale of millimeters. A calibration curve or function is first established to correlate light transmission through a slab of sandstone on the order of 5 to 10 mm under known conditions. This curved is then used to determine unknown conditions by measuring light transmission and comparing the values to those on the curve. Other applications for the phenomenon of light transmission through porous media are disclosed whereby conditions in a flowing stream of liquid can be monitored by use of light transmission. Specifically, changes in the refractive index and immiscible contamination can be detected. Finally, the phenomenon described can be used to model subterranean hydrocarbon bearing reservoirs, particularly fluid flow at different points in the reservoir, using light rather than hydraulic flows to simulate fluid flow patterns.

Method and apparatus for imaging porous media and method for fabricating

A method and apparatus measures dielectric properties over a broad range of frequencies. The functions of various resistivity and dielectric constant measuring devices such as logging tools are combined in a single tool. A measuring tool includes novel transmitting and receiving antennas. Electromagnetic energy flows to a transmitting antenna. A stripline adapter permits transmission to a stripline having a metallic central strip. A strip face is bent at approximately right angles, and has a length that is compatible with the desired frequency coverage. A ground plane extends from the stripline adapter to the right angle bend, and a void exists between the center strip and the ground plane. A dielectric is positioned to nearly fill the void. The antennas are positioned so that the strip face lies flush with the tool face, to permit electromagnetic energy to be transmitted into and out of the material to be analyzed. An enclosure comprised of four metallic walls surrounds the stipline, and is in electrical contact with the ground plane and the stripline adapter. The invention permits an analysis of the fluids in the material as well.

Method and apparatus for broadband measurement of dielectric properties

A method and apparatus for determining the water content of crude oil in a pipeline is disclosed. The device consists of S-band tarnsmitting and receiving antennas, and X-band transmitting and receiving antennas. These are used to determine the complex dielectric constant of the fluid in a pipeline. Water salinity and an adjustment to the mixing formula are calculated using X-band and S-band sidewall links. The overall water content of the pipeline can then be determined by using as S-band main link that transmits a wave through a representative portion of the entire pipeline.

Microwave system for monitoring water content in a petroleum pipeline

A sample accommodator for the measurement of dielectric properties includes a conductive strip having two planar surfaces, and two ground planes, one parallel to each of the planar surfaces of the conductive strip. At each end, the strip passes through but is electrically isolated from an endplate which is electrically and physically connected to each ground plane and which maintains the relative positions of the ground planes. Dielectric properties are measured by placing a sample between each face of the strip and the ground plane parallel to it.

Sample accommodator and method for the measurement of dielectric

A method and apparatus for determining the interface between two materials having different dielectric properties, especially in determining the thickness of a hydrocarbon layer on ground water, is disclosed. The apparatus consists of an air-filled, cased surveillance well in which a logging tool is raised and lowered. The logging tool contains an electromagnetic receiving antenna and two transmitting antennas located above and below the receiving antenna. A first wave and a second wave are transmitted from the transmitting antennas. The first and second waves are offset 180.degree. to produce 'sum' and 'delta' signals using a 1/2.degree. hybrid. Alternatively, a single wave can be transmitted from a central transmitting antenna to receiving antennas located above and below the transmitting antenna. The received signals are then phase shifted 180.degree. using a 180.degree. hybrid to produce sum and delta signals. As the tool is raised and lowered in the well bore, changes in the sum and delta signals will be observed when an interface is passed. A logging tool for use in petroleum production and exploration wells is also disclosed.

Growing community of inventors

Laguna Beach, CA, United States of America

Bibhas R De