AN INNOVATIVE SLIM PULSED NEUTRON LOGGING TOOL - APRIL 13 2016
Speaker: Dr. Tong Zhou
Date: Nov. 19, 2015
Location: Kinder Morgan - First Floor Conference Room, 1001 Louisiana St Houston, TX 77002
Parking: Travis Garage across milam, in front of Kinder Morgan, Open Air parking between Kinder Morgan and Shell N 2
A new-generation slim pulsed neutron logging tool has been developed to deliver reliable answers for formation evaluation and reservoir monitoring in conditions where existing technologies struggle, including temperatures up to 175C. The tool introduces a stand-alone fast neutron measurement that is independent of neutron porosity and sigma formation properties but is highly sensitive to variations in gas volume while insensitive to variations in water volume. Additionally, the tool provides high-resolution spectroscopy as well as self-compensated sigma and neutron porosity measurements in a wide range of environmental conditions.
The improvements in hardware over previous-generation tools include a high-output pulsed neutron generator (PNG), a compact neutron monitor (CNM), two lanthanum bromide (LaBr3) gamma ray detectors, and an yttrium aluminum perovskite (YAP) gamma ray detector at a longer spacing from the source. The diamond-based CNM accurately measures the neutron output of the PNG and normalizes the count rate of the YAP detector, which makes the stand-alone gas measurement possible. The high-neutron output and a fast acquisition system improve the precision of the measurements, enabling faster logging speeds. The PNG pulsing scheme is designed to optimize the gas, sigma, and neutron porosity measurements in terms of both accuracy and precision. The LaBr3 detectors have a fast response time, excellent energy resolution, and minimal temperature degradation, which enhance the capture and inelastic spectroscopy performance, particularly at high temperatures.
Several log examples demonstrate how the measurements from this tool improve formation evaluation and reservoir monitoring in the complex cased-hole environment, where slim pulsed neutron tools are often deployed.
Biography: Tong Zhou got his PhD degree in nuclear engineering from North Carolina State University (USA) in 2006. After that, he joined Schlumberger Doll Research at Boston as a research Post-doc scientist. In 2009, he transferred to Houston Formation Evaluation Center as a senior tool physicist working on nuclear logging tool development