HR: 11:30h
AN: U42A-05    [Abstracts]
TI: Wireline and LWD Sonic data: Similarities and Differences
AU: * Market, J
EM: jennifer.market@halliburton.com
AF: Halliburton, 300 N Sam Houston Pkwy E, Houston, tx 77032 United States
AU: Cheng, A
AF: SensorWise, Inc., 2908 Rogerdale Rd, United States
AU: Blanch, J
AF: SensorWise, Inc., 2908 Rogerdale Rd, United States
AB: Wireline sonic data has been an integral part of the logging suite for many years, providing reliable compressional and shear data, along with a suite of applications such as Stoneley permeability, anisotropy and casing bond logs. More recently, LWD sonic logs have become an increasingly common component of the drill string. Whereas the many similarities of the data allow for substitution of LWD for wireline in many situations, there are also differences in the measurements due to the inherent differences in the environment. Perhaps the most under-appreciated difference is exposure time. The LWD data is generally acquired only minutes behind the bit, while wireline data is often acquired many hours or even days after drilling. This time difference can lead to differences in velocities, as the LWD tools are seeing more pristine (less degraded) formations than wireline. The exposure time differences can actually be very useful information if logs are acquired at multiple times. Other differences between wireline and LWD include slow shear measurements, centralisation, and telemetry issues. We will review some of these similarities and differences in detail, showing modelling and field data for several wells.
DE: 5100 PHYSICAL PROPERTIES OF ROCKS
SC: Union [U]
MN: 2005 Joint Assembly