skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Investigation of Neutron Detector Response to Varying Temperature and Water Content for Geothermal Applications

Conference ·
OSTI ID:1000421

Nuclear logging techniques have been used for oil well logging applications for decades. The basic principle is to use a neutron and/or photon source and neutron and photon detectors for characterization purposes. Although the technology has matured, it is not directly applicable to geothermal logging due to even more challenging environmental conditions, both in terms of temperature and pressure. For geothermal logging, the operating temperature can go up to 376 C for depths up to 10,000 km. In this paper, the preliminary computational results for thermal neutron detector response for varying temperature and water content for geothermal applications are presented. In this summary, preliminary results for neutron detector response for varying formation temperature and water content are presented. The analysis is performed for a steady state source (AmBe) and time dependent source (PNG) in pulsed mode. The computational results show significant sensitivity to water content as well as temperature changes for both steady state and time dependent measurements. As expected, the most significant change is due to the temperature change for S({alpha}, {beta}) nuclear data instead of individual isotope cross sections for the formation. Clearly, this is partially because of the fact that strong absorbers (i.e., chlorine) are not taken into account for the analysis at this time. The computational analysis was performed using the temperature dependent data in the ENDF/B-VII libraries, supplied with MCNP. Currently, the data for intermediate temperatures are being generated using NJOY and validated. A series of measurements are planned to validate the computational results. Further measurements are planned to determine the neutron and photon detector response as a function of temperature. The tests will be performed for temperatures up to 400 C.

Research Organization:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
DOE Contract Number:
DE-AC05-00OR22725
OSTI ID:
1000421
Resource Relation:
Conference: 2010 ANS Winter Meeting and Nuclear Technology Expo, Las Vegas, NV, USA, 20101107, 20101111
Country of Publication:
United States
Language:
English