Effects of natural zeolites on field-scale geologic noble gas transport

Effects of natural zeolites on field-scale geologic noble gas transport

Forecasting

National security

Low permeability reservoirs

Petroleum reservoir engineering

Oil field equipment

Predictive analytics

Zeolites

Gas adsorption

Natural gas fields

Network security

Minerals

Inert gases

Signal to noise ratio

Radiation detectors

Nuclear explosions

Systematic errors

Improving predictive models for noble gas transport through natural materials at the field-scale is an essential component of improving US nuclear monitoring capabilities. Several field-scale experiments with a gas transport component have been conducted at the Nevada National Security Site (Non-Proliferation Experiment, Underground Nuclear Explosion Signatures Experiment). However, the models associated with these experiments have not treated zeolite minerals as gas adsorbing phases. This is significant as zeolites are a common alteration mineral with a high abundance at these field sites and are shown here to significantly fractionate noble gases during field-scale transport. This fractionation and associated retardation can complicate gas transport predictions by reducing the signal-to-noise ratio to the detector (e.g. mass spectrometers or radiation detectors) enough to mask the signal or make the data difficult to interpret. Omitting adsorption-related retardation data of noble gases in predictive gas transport models therefore results in systematic errors in model predictions where zeolites are present.Herein is presented noble gas adsorption data collected on zeolitized and non-zeolitized tuff. Experimental results were obtained using a unique piezometric adsorption system designed and built for this study. Data collected were then related to pure-phase mineral analyses conducted on clinoptilolite, mordenite, and quartz. These results quantify the adsorption capacity of materials present in field-scale systems, enabling the modeling of low-permeability rocks as significant sorption reservoirs vital to bulk transport predictions. 2020 Elsevier Ltd

220-221

Journal of Environmental Radioactivity

2020

Feldman, Joshua

Paul, Matthew

Xu, Guangping

Rademacher, David X.

Wilson, Jennifer

Nenoff, Tina M.

journalArticle

0265931X

10.1016/j.jenvrad.2020.106279