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Chemical changes in hot springs, as recorded by thermal waters and their deposits, provide a window into the evolution of the postglacial hydrothermal system of the Yellowstone Plateau Volcanic Field. Today, most hydrothermal travertine forms to the north and south of the ca. 631 ka Yellowstone caldera where groundwater flow through subsurface sedimentary rocks leads to calcite saturation at hot springs. In contrast, low-Ca rhyolites dominate the subsurface within the Yellowstone caldera, resulting in thermal waters that rarely deposit travertine. We investigated the timing and origin of five small travertine deposits in the Upper and Lower Geyser Basins to understand the conditions that allowed for travertine deposition. New 230Th-U dating, oxygen (δ18O), carbon (δ13C), and strontium (87Sr/86Sr) isotopic ratios, and elemental concentrations indicate that travertine deposits within the Yellowstone caldera formed during three main episodes that correspond broadly with known periods of wet climate: 13.9−13.6 ka, 12.2−9.5 ka, and 5.2−2.9 ka. Travertine deposition occurred in response to the influx of large volumes of cold meteoric water, which increased the rate of chemical weathering of surficial sediments and recharge into the hydrothermal system. The small volume of intracaldera travertine does not support a massive postglacial surge of CO2 within the Yellowstone caldera, nor was magmatic CO2 the catalyst for postglacial travertine deposition.
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High-resolution structure-from-motion models of hydrothermal sites in the Central Nevada Seismic Belt: applications in tectonic, climate, and hydrothermal investigations
ABSTRACT Hot spring travertine and sinter deposits record discharge from hydrothermal systems through evolving hydrothermal, hydrologic, and tectonic regimes. The location and volume of the largest deposits may reflect persistent or particularly robust periods of hydrothermal flow. As part of a broader investigation into the chemical evolution of travertine deposits, we used unoccupied aerial vehicles (UAVs) coupled with high-precision GPS surveys to collect and assemble orthorectified photomosaics and high-resolution digital elevation models (DEMs) using structure-from-motion (SfM) software for eight sites in the northern Central Nevada Seismic Belt. These sites range from large, intrabasin travertine mounds to travertine and sinter deposits offset by Quaternary faults. Some highlights of the research made possible by the acquisition of these topographic datasets include: 1) geomorphic evidence that hydrothermal flow at Hyder Hot Springs has persisted since at least the last highstand of glacial Lake Dixie, 2) documenting the impact of hot spring sinter and hydrothermal alteration on the preservation and morphology of Quaternary fault scarp profiles, 3) mapping the extent of a large extinct travertine deposit in the Stillwater Range, and 4) constraints on the offset of hot spring deposits affected by Quaternary faulting at Kyle Hot Springs. Areas between 0.51 – 1.23 km^2 (126-303 acres) were easily acquired with less than half a day of surveying and flying, and models capable of producing orthorectified photomosaics and DEMs with average resolution of 2.5 cm/pixel and 9.7 cm/pixel, respectively, were built on a desktop computer with 1-10 days of processing time. In desert landscapes, the resolution of the resulting DEMs approaches that of bare earth LiDAR datasets at a fraction of the cost, with little to no special permitting in most cases, and with limited preplanning. The imagery and models described herein are freely available from the NSF-EAR-funded data facility OpenTopography (https://portal.opentopography.org/datasets) for use in commercial, academic, and educational applications with proper attribution.
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- Award ID(s):
- 2040716
- PAR ID:
- 10400573
- Date Published:
- Journal Name:
- Proceedings 48th Workshop on Geothermal Reservoir Engineering, Stanford University, Stanford, California.
- Page Range / eLocation ID:
- SGP-TR-224
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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