A New LWD Imaging Tool for Use in Oil-Based Muds

Michael Gillen, Stephen Dymmock, Brian Moody

Baker Hughes, a GE company

Posted: June 30, 2019

Abstract

Title: A New LWD Imaging Tool for Use in Oil-Based Muds

Michael Gillen, Stephen Dymmock, Brian Moody, Baker Hughes, a GE company

Abstract control # 2019-A-640-AAPG

A new logging-while-drilling (LWD) ultrasonic imaging tool has been field tested and shown to provide

high-resolution images that give early indications of problems during drilling operations and provides

information on the geologic structure and sedimentary features. These images are compared to other

LWD imaging techniques to demonstrate the advantages of the new technology.

The system employs three equally spaced ultrasonic transducers mounted at the same level in the tool.

This arrangement provides the high data density needed for high-quality images. The technology enables

full borehole image acquisition at rates of penetration (ROP) up to 400 feet/hour, thereby not impacting

the drilling operations, even in the high ROP environment of the US unconventional drilling environment.

For real-time operations, the images are used to monitor wellbore stability issues that can lead to non-

productive time (NPT) during drilling operations.

These field tests demonstrated the capabilities of the images to identify wellbore stability issues such as

breakouts and cavings. Examples showing the images, along with other measurements, provide a

superior technique for wellbore stability management in real-time. The images are also used to identify

geologic features such as bedding, fractures and faults. Examples will be illustrating how the images are

used for structural dip determination and to identify sedimentary features.

The new technology provides a much clearer image of the borehole that has been available in the past in

OBM systems. The techniques developed for using this information in real-time reduce the frequency and

magnitude of borehole-related NPT events. The images are very useful in the US unconventional

reservoirs to identify fractures and faults that could impact the production and economics of the well.