A small-diameter NMR logging tool for groundwater investigations.

Autor: Walsh D; Vista Clara Inc., 12201 Cyrus Way, Suite 104, Mukilteo, WA., Turner P, Grunewald E, Zhang H, Butler JJ Jr, Reboulet E, Knobbe S, Christy T, Lane JW Jr, Johnson CD, Munday T, Fitzpatrick A
Jazyk: angličtina
Zdroj: Ground water [Ground Water] 2013 Nov-Dec; Vol. 51 (6), pp. 914-26. Date of Electronic Publication: 2013 Feb 20.
DOI: 10.1111/gwat.12024
Abstrakt: A small-diameter nuclear magnetic resonance (NMR) logging tool has been developed and field tested at various sites in the United States and Australia. A novel design approach has produced relatively inexpensive, small-diameter probes that can be run in open or PVC-cased boreholes as small as 2 inches in diameter. The complete system, including surface electronics and various downhole probes, has been successfully tested in small-diameter monitoring wells in a range of hydrogeological settings. A variant of the probe that can be deployed by a direct-push machine has also been developed and tested in the field. The new NMR logging tool provides reliable, direct, and high-resolution information that is of importance for groundwater studies. Specifically, the technology provides direct measurement of total water content (total porosity in the saturated zone or moisture content in the unsaturated zone), and estimates of relative pore-size distribution (bound vs. mobile water content) and hydraulic conductivity. The NMR measurements show good agreement with ancillary data from lithologic logs, geophysical logs, and hydrogeologic measurements, and provide valuable information for groundwater investigations.
(© 2013, National Ground Water Association.)
Databáze: MEDLINE
Externí odkaz: