These brine samples are collected from the Soda Geyser (a thermal feature, temperature ~30 C) in Soda Springs, Idaho. These samples also represent the overthrust brines typical of oil and gas plays in western Wyoming. Samples were collected from the source and along the flow channel at different distances from the source. By collecting and analyzing these samples we are able to increase the density and quality of data from the western Wyoming oil and gas plays. Furthermore, the sampling approach also helped determine the systematic variation in REE concentration with the sampling distance from the source. Several geochemical processes are at work along the flow channels, such as degassing, precipitation, sorption, etc.

These brine samples are collected from the Soda Geyser (a thermal feature, temperature ~30 C) in Soda Springs, Idaho. These samples also represent the overthrust brines typical of oil and gas plays in western Wyoming. Samples were collected from the source and along the flow channel at different distances from the source. By collecting and analyzing these samples we are able to increase the density and quality of data from the western Wyoming oil and gas plays. Furthermore, the sampling approach also helped determine the systematic variation in REE concentration with the sampling distance from the source. Several geochemical processes are at work along the flow channels, such as degassing, precipitation, sorption, etc.

We have conducted aqueous speciation analyses of the Great Salt Lake (GSL) brine sample (Table 1) and a mock geo sample (Table 2) spiked with 1 ppb Tb and 100 ppb Tb. The GSL speciation (Figure 1) aligns with our basic speciation expectations that strong carbonate complexes would form at mid to higher pH's. Although we expected strong aqueous complexes with fluorides at neutral pH and with chlorides, and hydroxides at low pH, we observe that the dominant species in the low to mid pH range to be Tb3+ as a free ion. Still, we do see the presence of fluoride and chloride complexes within the expected low to mid pH range.

Presentation given to National Groundwater Association meeting on deep basin brines. This presentation discusses why produced waters are being observed, the importance of REE's, the study areas examined, the data collected, and the relationship between REE concentration and possible ligands.

Presentation given to National Groundwater Association meeting on deep basin brines. This presentation discusses why produced waters are being observed, the importance of REE's, the study areas examined, the data collected, and the relationship between REE concentration and possible ligands.

This work was developed to complement the geochemical assessments of produced water and geothermal water samples. Specifically, this task was designed to test the influence of reservoir rock-type and corresponding mineralogy/geochemistry on the concentrations of REE found in oil and gas produced waters. There has been no direct investigation of REE reactions relative to rock-type in deep oil and gas brine prior to this investigation.

Shaker test data comparing rare earth element (REE) sorption onto Tusaar media between one natural geothermal brine and two simulated brines doped with known mineral concentrations.

This study is part of a joint effort by the University of Wyoming (UW) School of Energy Resources (SER), the UW Engineering Department, Idaho National Laboratories (INL), and the United States Geological Survey (USGS) to describe rare earth element concentrations in oil and gas produced waters and in coal-fired power station ash ponds. In this work we present rare earth element (REE) and trace metal behavior in produced water from four Wyoming oil and gas fields and surface ash pond water from two coal-fired power stations. Using the methods of the INL team members, we measured REEs in high salinity oil and gas produced waters. Our results show that REEs exist as a dissolved species in all waters measured for this project, typically within the parts per trillion range.