earth science

Glen Snyder

Research Scientist

Ph.D (2001) University of Rochester

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Publication list (pdf).

Curriculum vitae (pdf)


Phone: (713)348-4054

Office: Keith Weiss Earth Science 330B

Rice Earth Science
Coalbed methane systems:

Despite growing commercial interest in coalbed methane resources, surprisingly little is known about the hydrologic systems which have maintained gas in the coals, and their long-term response to human activity. Growing concerns about the effect of removal of co-produced brines on local water quality have made the need for knowing even short-term consequences imperative. We use a variety of naturally occurring environmental tracers to determine the source an migration of brines, including 129I, 36Cl, 2H, and 18O. Research was carried out on the Fruitland Formation coals of the San Juan Basin in New Mexico and Colorado. In central portions of the basin, iodine ages correlated with the 73 Ma depositional age of the coals, showing minimal migration of entrapped fluids. Infiltration on the uplifted edges of the basin were indicated by high concentrations of anthropogenic 129I.

Gas seeps in springs near coal outcrops are a major concern. Whether or not they are influenced by commercial gas production depends on the degree of hydrologic connectivity between areas of outcrop and the overpressured regions deep in the basin.
Methane brines have 2H/1H and 18O/16O ratios ranging from meteoric to near-seawater values. Both the formation of methane and methane oxidation have caused shifts from the Craig Global Meteoric Water Line. Blue triangles are rivers and streams. Red circles are high-iodine brines. Light blue circles are low-iodine brines. Yellow and orange have intermediate iodine concentrations.
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Deuterium values for brine waters within Fruitland Formation of the northern San Juan Basin
Dissolved iodine concentrations in brine waters within the basin. Iodine is primarily reduced as iodide.
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Ratios of 129iodine/127iodine in the San Juan Basin. Yellow areas show influx of recent surface waters. Violet regions preserve iodine signatures from the time of deposition of coal-forming peats.