Search Results

open access

Acoustical Imaging and Mechanical Properties of Soft Rock and Marine Sediments Progress Report: January-March 2001

Description: The oil and gas industry has encountered significant problems in the production of oil and gas from weak rocks (such as chalks and limestones) and from unconsolidated sand formations. Problems include subsidence, compaction, sand production, and catastrophic shallow water sand flows during deep water drilling. Together these cost the petroleum industry hundreds of millions of dollars annually. The goals of this first quarterly report is to document the progress on the project to provide data on… more
Date: April 1, 2001
Creator: Scott, Thurman E., Jr.; Zaman, Musharraf & Abousleiman, Younane
open access

Acoustical Imaging and Mechanical Properties of Soft Rock and Marine Sediments Progress Report: October-December 2001

Description: During this phase of the project the research team concentrated on acquisition of acoustic emission data from the high porosity rock samples. The initial experiments indicated that the acoustic emission activity from high porosity Danian chalk were of a very low amplitude. Even though the sample underwent yielding and significant plastic deformation the sample did not generate significant AE activity. This was somewhat surprising. These initial results call into question the validity of attempt… more
Date: January 31, 2001
Creator: Scott, Thurman E., Jr.; Abousleiman, Younane & Zaman, Musharraf
open access

Acoustical Imaging and Mechanical Properties of Soft Rock and Marine Sediments Progress Report: January-March 2002

Description: Three major goals were accomplished during this phase. First, a study was completed of the effects of stress-induced changes in anisotropic elastic moduli in sandstone. Second, a new method for measuring the anisotropic poroelastic moduli from acoustic data was developed. Third, a series of triaxial experiments were conducted on unconsolidated sands to identify pressure/stress conditions where liquefaction occurs under high confining pressures. Stress-induced changes in anisotropic Young's modu… more
Date: April 30, 2002
Creator: Scott Thurman E., Jr.; Abousleiman, Younane & Zaman, Musharraf
open access

Acoustical Imaging and Mechanical Properties of Soft Rock and Marine Sediments Progress Report: April-June 2002

Description: During the sixth quarter of this research project the research team developed a method and the experimental procedures for acquiring the data needed for ultrasonic tomography of rock core samples under triaxial stress conditions as outlined in Task 10. Traditional triaxial compression experiments, where compressional and shear wave velocities are measured, provide little or no information about the internal spatial distribution of mechanical damage within the sample. The velocities measured bet… more
Date: November 18, 2002
Creator: Scott, Thurman E., Jr.; Abousleiman, Younane & Zaman, Musharraf
open access

Acoustical Imaging and Mechanical Properties of Soft Rock and Marine Sediments Progress Report: April-June 2001

Description: Mechanically weak formations, such as chalks, high porosity sandstones, and marine sediments, pose significant problems for oil and gas operators. Problems such as compaction, subsidence, and loss of permeability can affect reservoir production operations. For example, the unexpected subsidence of the Ekofisk chalk in the North Sea required over one billion dollars to re-engineer production facilities to account for losses created during that compaction (Sulak 1991). Another problem in weak for… more
Date: July 1, 2001
Creator: Scott, Thurman E., Jr.; Abousleiman, Younane & Zaman, Musharraf
open access

Acoustical Imaging and Mechanical Properties of Soft Rock and Marine Sediments Progress Report: July-September 2002

Description: During the seven quarter of the project the research team analyzed some of the acoustic velocity data and rock deformation data. The goal is to create a series of ''deformation-velocity maps'' which can outline the types of rock deformational mechanisms which can occur at high pressures and then associate those with specific compressional or shear wave velocity signatures. During this quarter, we began to analyze both the acoustical and deformational properties of the various rock types. Some o… more
Date: November 18, 2002
Creator: Scott, Thurman E., Jr.; Abousleiman, Younane & Zaman, Musharraf
Back to Top of Screen