Abstract: Acoustic measurements are obtained and combined with some identification of regions that are expected or believed to be cemented. Based at least in part on this information, a processing unit derives an annular material classifier that can identify those measurements characteristic of the cemented regions (including regions cemented with a resin cement formulation), and that further applies the classifier to the measurements to generate a cement log that can be displayed to a user. Cross-plots of waveform amplitude, acoustic impedance, and the derivative of acoustic impedance, have revealed that resin cement, for example, has characteristic acoustic properties that form a small cluster within the range of expected measurements. For improved identification reliability, such clusters can be identified adaptively.

Abstract: A cement bond logging method for wells containing heavy mud and cement is provided. Acoustic logging tool data from a well having material in the annular space between the casing and the formation is analyzed to map relationships between waveform amplitude, acoustic impedance, and impedance derivative of the material. Map zones representing fully bonded well regions and partially bonded well regions are identified. An image is generated from the log data corresponding to the identified map zones. A cement bond logging system including a memory having cement bond logging software and a processor coupled to the memory to execute the software is also provided.

Abstract: A cement bond logging method for wells containing heavy mud and cement is provided. Acoustic logging tool data from a well having material in the annular space between the casing and the formation is analyzed to map relationships between waveform amplitude, acoustic impedance, and impedance derivative of the material. Map zones representing fully bonded well regions and partially bonded well regions are identified. An image is generated from the log data corresponding to the identified map zones. A cement bond logging system including a memory having cement bond logging software and a processor coupled to the memory to execute the software is also provided.

Abstract: A method for determining the downhole flow regime in a horizontal well borehole traversing a subterranean formation. A first gas holdup value within the borehole is measured using a fluid density tool. A second gas holdup value within the borehole is measured using a fullbore gas-holdup tool. The downhole flow regime is then determined as a function of the first gas holdup value and the second gas holdup value. A downhole flow regime comprised of dispersed bubble flow is indicated where the first gas holdup value is approximately equal to the second gas holdup value. A downhole flow regime comprised of annular flow is indicated where the first gas holdup value is substantially greater than the second gas holdup value and the velocity of the gas phase is substantially greater than the liquid phase. A downhole flow regime comprised of stratified flow is indicated where the first gas holdup value is less than or greater than the second gas holdup value.