Micro-sonic density imaging while drilling systems and methods

Patent metadata

Field	Value
Publication number	US-10041343-B2
Application number	US-201013813343-A
Country	US
Kind code	B2
Filing date	Sep 22, 2010
Priority date	Jun 2, 2009
Publication date	Aug 7, 2018
Grant date	Aug 7, 2018

Abstract

Various micro-sonic density imaging-while-drilling systems and methods are disclosed. In at least some forms, the micro-sonic logging tool is embodied in a drill collar having at least one stabilizer blade. One or more acoustic transmitters are set in a distal face of the stabilizer blade to generate acoustic waves. One or more receivers can also be set in the distal face of the stabilizer blade to detect P-waves and S-waves that have propagated through the formation making up the borehole wall. Processing circuitry measures the velocity or slowness of the acoustic waves and optionally associates the measured values with a spot on the borehole wall as identified. Multiple transmitters can be used if it is desired to obtain compensated measurements. The tool can further include a fluid cell to measure acoustical properties of the borehole fluid, which can be used to convert the formation slowness measurements into density measurements.

First claim

What is claimed is:

1. A logging method that comprises:
rotating a logging-while-drilling tool as it moves along a borehole;
detecting acoustic waves propagating along a wall of the borehole using at least two receivers;
processing signals from the receivers to measure formation density values; and
associating the formation density values with the tool's position and orientation.

2. The method of claim 1 , further comprising displaying a borehole wall image calculated based at least in part on the formation density values.

3. The method of claim 1 , wherein the processing includes measuring P-wave and S-wave slowness values and determining said formation densities based at least in part on the P-wave and S-wave slowness values.

4. The method of claim 1 , wherein the receivers are set in a distal face of a protrusion on the tool.

5. The method of claim 4 , further comprising: generating acoustic waves using a transmitter on the distal face, said distal face being on a stabilizer blade attached to the tool.

6. The method of claim 5 , further comprising:
generating acoustic waves using a second transmitter on the distal face of said stabilizer blade,
wherein the receivers are on a line between the transmitters and spaced equally from a midpoint between the transmitters.

7. The method of claim 5 , wherein the receivers are less than 2 inches apart and are no more than 20 inches from the transmitter.

8. The method of claim 4 , wherein the distal face remains within 0.3 inches of the borehole wall as the tool rotates.

9. The method of claim 1 , further comprising transmitting waveforms via wired drillpipe to the surface for processing.

10. The method of claim 1 , wherein said processing signals from the receivers to measure formation density includes using a fluid cell to measure acoustic impedance of fluid in the borehole.

Assignees

• Chemali Roland E
• Oraby Moustafa E
• Halliburton Energy Services Inc

Inventors

• Chemali Roland E
• Oraby Moustafa E

Classifications

• G01V1/46 Primary

  Data acquisition · CPC title

• E21B47/00 Primary

  Survey of boreholes or wells (monitoring pressure or flow of drilling fluid E21B21/08) · CPC title

• E21B47/0025 Primary

  generating an image of the borehole wall using down-hole measurements, e.g. acoustic or electric · CPC title