A COMPARISON OF CLAY AND TRAVERTINE MATERIAL FROM THE BORAX LAKE AND MICKEY HOT SPRINGS GEOTHERMAL SYSTEMS, ALVORD BASIN, OREGON
In spite of superficial similarities, there are distinct differences between the two systems; for example, there is fumerolic discharge at Mickey Hot Springs, which is absent at Borax Lake. In order to further investigate the differences between the two areas we collected a series of geothermal muds, sinter, travertine, and loose rock material from both systems. Preliminary analyses of these samples show definite differences between the areas. All travertine material collected was predominately calcium carbonate, with minor smectite. At Mickey Hot Springs the thermal mud samples were predominately smectite; however, the samples also contained minor amounts of kaolinite and haloysite. One surface rock sample also contained illite, and the older sinter material contained amorphous silica rather than carbonate material. The Borax Lake samples indicate much lower temperature near the surface, as smectite was the only clay detected, and all other surface deposits were calcium carbonate. The results of our preliminary analyses suggest that boiling is occurring closer to the surface in the Mickey Hot Springs system, and that chemically the Mickey system has been more diverse in the past.