CONDITIONS FOR MODERN SILICEOUS GEL FORMATION: ALVORD HOT SPRINGS, OREGON

Siliceous gels have been hypothesized to be precursors to chert formation (Leet et al., 2021), yet little is understood of the conditions for modern gel formation. Alvord Springs, Oregon, serves as a crucial modern natural environmental laboratory, warranting comprehensive study to understand its ecological dynamics. Geothermal spring discharge at Alvord Springs can be traced from source to the margins of the Alvord desert. Siliceous gels and microbial communities are abundant in a select portion of the stream. Further analysis of gels and waters along this spring discharge zone were conducted from samples collected in August 2023. X-ray fluorescence (XRF) analysis of mat material confirms an abundance of silica content within microbial mats and gels. In situ measurements of spring waters shows an increase in pH and decrease in temperature from spring source to the Alvord desert shoreline, with siliceous gels abundant at pH ranges of 8-9 and temperatures below 50℃.