Showing papers in "Journal of Petroleum Technology in 1976"

Polyacrylamide/potassium-chloride mud for drilling water-sensitive shales

Abstract: A shale-protective, water-base drilling fluid containing a high molecular-weight, partially hydrolyzed polyacrylamide and potassium chloride has been used in many wells around the world. A laboratory test for evaluating the ability of water-base muds to protect stressed shales under dynamic conditions was used in the initial development of the system. Field application of the polyacrylamide/potassium-chloride mud has been successful in stabilizing hard, sloughing shales in Canada and in reducing shale-related hole problems in several offshore areas. Recent use in the Canadian Arctic has extended the application to weighted muds for drilling soft, mud-producing shales.

Hindcasting the Directional Spectra of Hurricane-Generated Waves

Abstract: A method for specifying hurricane-generated waves in the Gulf of Mexico in terms of the directional wave spectrum has been developed. The method includes a description of the surface-wind field from historical meteorological data through the application of a dynamic-hurricane frictional boundary-layer model.

Improved Hydrocarbon Reservoir Evaluation Through Use of Borehole-Gravimeter Data

Abstract: A review of lateral and vertical response characteristics of various logging devices indicates that correction of logging responses for borehole and near-borehole effects is inadequate when rock heterogencity or filtrate invasion characteristics approach or exceed the bulk resolution of conventional logging devices. The lateral response of borehole gravimeters is shown to be a function of the geometry of density contrasts along a lateral plate of infinite extent, resulting in bulk-volume porosity measurements compatible with deep-investigating resistivity devices. Special logging techniques and the evaluation of tool characteristics of the borehole gravimeter have resulted in successful applications of borehole gravimetry to reservoir analysis.

Gas Leakage in Primary Cementing - A Field Study and Laboratory Investigation

Abstract: In laboratory and field tests, Halliburton Services has successfully prevented gas leakage in cemented gas storage wells by using cement slurries having a fluid loss of 50 ml/30 min. filtrate loss from a cementing slurry is limited by the presence of mud filter cake and increased by a rise in differential pressure. Gas differential pressure applied to initial or final set cement with high-fluid-loss properties may produce microcapillaries which will act as permanent channels for gas migration. Low-fluid-loss slurries maintain low permeability during the setting process.

Natural Frequencies of Marine Drilling Risers

Abstract: This paper presents data relating the first five natural frequencies of marine drilling risers to typical riser and drilling parameters. The riser is idealized as a vertical flexible beam with pinned supports. Variable tension and fluid environment make the mathematics different from classical beam theory, leading to a differential equation that perhaps is unique to the oil industry. Exact natural frequencies or eigenvalues are compared with frequencies obtained using an approximate method based on classical, uniformly tensioned beam equations. An example calculation is given.

Evaluation of polyacrylamides for reducing water production

Abstract: This investigation of polyacrylamides focuses on determining which properties are most important for reducing the permeability to water and how these properties relate to the success of treatments in the field. The tests show that shear degradation of polyacrylamides does not necessarily reduce their effectiveness. Compatibility of the polyacrylamide solution with both the formation matrix and the formation water is important, and best results are expected in wells where water and oil are being produced from different layers. Oil production may be restricted by injudicious use of cross-linking agents, undissolved polyacrylamide, extremely high concentrations of polymer, or by treating sandstones that have high clay contents.

Enhanced Crude Oil Recovery Potential-An Estimate

Abstract: Introduction and Summary Examination of published API datal on domestic reserves of crude oiI results in several interesting observations concerning the present status and future direction for the United States oil industry. Comparison of the low discovery rate of new reserves that the industry has experienced in the past — notwithstanding the discovery of Pwdhoe Bay — with our present domestic demands for crude oil is striking. These discrepancies promise to have a dramatic effect on our domestic’”oil industry in years to come as the large fields discovered in the i930’s and 1940’s are depleted. The foremost conclusion of this report, in common with that of many others, is that large, new domestic sources of crude oil need to be discovered and developed soon. Or, alternatively, an economically viable, massive substitute for domestic oil must be developed soon. The second conclusion’is that, contrary to many opinions, the cumulative oil reservoir recovery efficiency in the U.S. has been decreasing for a number of years, with the exception of a slight lift from the discovery of Prudhoe Bay.”We can be certain that this is no way caused by poor or mediocre engineering, or by any arbitrary or poorly conceived decisions by management. The changes that have occurred in recovery efficiency with time are merely and exclusively caused by the sequence in which different types of oil fields we~ediscovered in various locations in the U.S. Study of the recovery-efficiency data has permitted

Effect of Wellbore Storage and Wellbore Damage at the Active Well on Interference Test Analysis

Abstract: Interference testing is used to estimate reservoir transmissivity and storativity. This paper shows that wellbore storage and wellbore damage at the active well reduce the pressure response at an observation well, especially at early times, and can cause considerable error in estimating reservoir properties if these factors are not properly accounted for. New type curves are presented that include the effects of wellbore storage and damage. A simulated example problem and a field case are presented to show what magnitude of error might be encountered when interference tests are analyzed improperly.

Ocean Data Gathering Program - Quality and Reduction of Data

Abstract: Data collected from six offshore platforms in the Gulf of Mexico from 1968 to 1971 during the Ocean Data Gathering Program are probably the most complete set of wind and wave measurements available off the Louisiana coast. The data and their quality, calibration, and usability are discussed with an eye toward familiarizing the potential user with the possibilities of the system.

Corrosion Testing of Highly Alloyed Materials For Deep, Sour Gas Well Environments

Abstract: A more practical system for completing sour gas wells may be to use materials that possess innate corrosion resistance rather than to attempt chemical corrosion inhibition of steel alloys. This paper presents results of screening tests designed to select candidates among highly alloyed materials for use in produced environments containing water, salt, hydrogen sulfide, and carbon dioxide at 450/sup 0/F and 20,000 psi. Alloy systems containing large amounts of nickel, cobalt, chromium, and molybdenum were found to have exceptional corrosion resistance for this environment. The alloys also retain their corrosion resistance at yield strengths of 150,000 to 250,000 psi, thereby significantly extending the capacity to complete and produce deep reservoirs.