Abstract: Methods and apparatus are disclosed for measuring the permeability and/or porosity of ultra-low permeable rock samples. In some embodiments, the methods utilize fluid pressure perturbation.

Abstract: Methods and apparatus are disclosed for measuring the permeability and/or porosity of ultra-low permeable rock samples. In some embodiments, the methods utilize fluid pressure perturbation.

Abstract: Methods are provided for measuring the permeability and/or porosity of a rock sample having an “ultra-low” permeability while accounting for adsorption. The rock sample may be a sample obtained from a geological formation. The methods account for adsoption of gas within the rock samples.

Abstract: Apparatus and calibration methods are disclosed for measuring the permeability and/or porosity of ultra-low permeable rock samples. The apparatus uses a gas source, a sample chamber, chambers of calibrated volume, and pressure measurement devices.

Abstract: Methods and apparatus are disclosed for measuring the permeability and/or porosity of ultra-low permeable rock samples. In some embodiments, the methods utilize fluid pressure perturbation.

Abstract: Methods are provided for measuring the permeability and/or porosity of a rock sample having an “ultra-low” permeability while accounting for adsorption. The rock sample may be a sample obtained from a geological formation. The methods account for adsoption of gas within the rock samples.

Abstract: Apparatus and calibration methods are disclosed for measuring the permeability and/or porosity of ultra-low permeable rock samples. The apparatus uses a gas source, a sample chamber, chambers of calibrated volume, and pressure measurement devices.

Abstract: Methods and apparatus are disclosed for measuring the permeability and/or porosity of ultra-low permeable rock samples. In some embodiments, the methods utilize fluid pressure perturbation.

Abstract: Earth formations are characterized by using an array of electrodes which can measure streaming potentials in the formation, and by interpreting the data obtained by the electrodes. The electrodes are placed on a wireline tool, a LWD tool, or in a fixed manner about a completed wellbore. The measured streaming potentials are generated by drilling with an overbearing pressure, slitting the mudcake in a borehole, acid injection, or any of various other manners which causes fluid movement. The data obtained is interpreted to locate fractures, measure formation permeability, estimate formation pressure, monitor drilling fluid loss, detect abnormal pressure, etc. Particularly, a streaming potential voltage transient having a double peak profile signifies the presence of a formation fracture.

Abstract: Earth formations are characterized by using an array of electrodes which can measure streaming potentials in the formation, and by interpreting the data obtained by the electrodes. The electrodes are placed on a wireline tool, a LWD tool, or in a fixed manner about a completed wellbore. The measured streaming potentials are generated by drilling with an overbearing pressure, slitting the mudcake in a borehole, acid injection, or any of various other manners which causes fluid movement. The data obtained is interpreted to locate fractures, measure formation permeability, estimate formation pressure, monitor drilling fluid loss, detect abnormal pressure, etc. Particularly, a streaming potential voltage transient having a double peak profile signifies the presence of a formation fracture.

Abstract: Earth formations are characterized by using an array of electrodes which can measure streaming potentials in the formation, and by interpreting the data obtained by the electrodes. The electrodes are placed on a wireline tool, a LWD tool, or in a fixed manner about a completed wellbore. The measured streaming potentials are generated by drilling with an overbearing pressure, slitting the mudcake in a borehole, acid injection, or any of various other manners which causes fluid movement. The data obtained is interpreted to locate fractures, measure formation permeability, estimate formation pressure, monitor drilling fluid loss, detect abnormal pressure, etc. Particularly, a streaming potential voltage transient having a double peak profile signifies the presence of a formation fracture.

Abstract: Earth formations are characterized by using an array of electrodes which can measure streaming potentials in the formation, and by interpreting the data obtained by the electrodes. The electrodes are placed on a wireline tool, a LWD tool, or in a fixed manner about a completed wellbore. The measured streaming potentials are generated by drilling with an overbearing pressure, slitting the mudcake in a borehole, acid injection, or any of various other manners which causes fluid movement. The data obtained is interpreted to locate fractures, measure formation permeability, estimate formation pressure, monitor drilling fluid loss, detect abnormal pressure, etc. Particularly, a streaming potential voltage transient having a double peak profile signifies the presence of a formation fracture.

Abstract: A method for determining formation fluid pressure in earth formation surrounding a borehole wall uses a downhole probe coupled to a variable-volume cavity. The probe is driven into contact with formation at the borehole wall. The method includes expanding the volume of the cavity during a first period of time to establish fluid communication between tool fluid and formation fluid, by withdrawing a minimal amount of fluid from the formation. During a second period of time the tool pressure is allowed to equilibrate to formation pressure. When pressure equilibrium is established, formation fluid pressure is set equal to tool pressure. A preferred embodiment includes terminating expanding the volume of the cavity on detecting a break in the mud cake seal.

Abstract: A method and apparatus for analyzing a sample to determine its mineral composition. The invention combines X-ray diffraction with Fourier transform infrared spectroscopy to provide a complete spectrum including molecular vibrations, probed by FTIR scans and lattice spacing measured by X-ray diffraction in a single representation. This FX spectrum provides a more complete and accurate mineralogy than either of the techniques alone. In addition, new techniques for independent X-ray diffraction analysis and FTIR analysis are described.