Sara Peek manages the water and gas geochemistry labs for the California Volcano Observatory, and works on related volcano monitoring and research at California volcanoes, Yellowstone, and Hawaii.
Science and Products
Mineralogy, strontium (87Sr/86Sr), oxygen (18O/16O) and carbon (13C/12C) isotope composition, elemental concentrations, and U-Th disequilibrium ages for travertine deposits from various locations in Yellowstone National Park, USA
Chemical changes in hot springs, as recorded by thermal waters and their mineral deposits, provide a window into the evolution of Yellowstone’s postglacial hydrothermal system. Travertine precipitated from thermal waters provide a record of chemical changes through time because they can be dated using U-series disequilibrium geochronology. These temporal data, along with measured radiogenic 87Sr/8
Chemical and isotopic composition of gas, water, and solids from the 2019-2020 water lake in Halema’uma’u Crater, Kīlauea Volcano, Hawaii
Following the 2018 eruption of Kīlauea Volcano (Neal et al, 2019) and the subsequent collapse of the Halema’uma’u crater, groundwater gradually seeped into the newly-deepened crater (Nadeau and others, 2020). Water was first observed in the crater on 7/26/2019, and the water level increased over time until 12/20/2020, when the crater again filled with lava, vaporizing the lake. In the intervening
Geochemistry and fluxes of gases from hydrothermal features at Newberry Volcano, Oregon, USA
We present the chemical and isotopic compositions of gases and fluxes of CO2 from the hydrothermal features of Newberry Volcano, a large composite volcano located in Oregon's Cascade Range with a summit caldera that hosts two lakes, Paulina and East Lakes. Gas samples were collected from 1982 to 2021 from Paulina Hot Springs (PHS) on the shore of Paulina Lake, East Lake Hot Springs (ELHS) on the s
Authors
Jennifer L. Lewicki, William C. Evans, Steven E. Ingebritsen, Laura E. Clor, Peter J. Kelly, Sara Peek, Robert A. Jensen, Andrew Hunt
Mechanisms for retention of low molecular weight organic carbon varies with soil depth at a coastal prairie ecosystem
Though primary sources of carbon (C) to soil are plant inputs (e.g., rhizodeposits), the role of microorganisms as mediators of soil organic carbon (SOC) retention is increasingly recognized. Yet, insufficient knowledge of sub-soil processes complicates attempts to describe microbial-driven C cycling at depth as most studies of microbial-mineral-C interactions focus on surface horizons. We leverag
Authors
Jack McFarland, Corey Lawrence, Courtney Creamer, Marjorie S. Schulz, Christopher H. Conaway, Sara Peek, Mark Waldrop, Sabrina N. Sevilgen, Monica Haw
Stable isotopes provide insight into sources and cycling of N compounds in the Sacramento-San Joaquin Delta, California, USA
River deltas and their diverse array of aquatic environments are increasingly impacted by anthropogenic inputs of nitrogen (N). These inputs can alter the N biogeochemistry of these systems and promote undesirable phenomena including harmful algae blooms and invasive aquatic macrophytes. To examine N sources and biogeochemical processes in the Sacramento-San Joaquin Delta, a river delta located in
Authors
Joseph K. Fackrell, Tamara E. C. Kraus, Megan B. Young, Carol Kendall, Sara Peek
The structure and volume of large geysers in Yellowstone National Park, USA and the mineralogy and chemistry of their silica sinter deposits
Siliceous sinter is formed by biogenic and abiogenic opal deposition around hot springs and geysers. Using Structure-from-Motion photogrammetry we generated three-dimensional models of Giant and Castle Geysers from the Upper Geyser Basin of Yellowstone National Park. We use these models to calculate an approximate mass of sinter for each (~2 and ~ 5 kton, respectively) and estimate a range of plau
Authors
Dakota Churchill, Michael Manga, Shaul Hurwitz, Sara Peek, David Damby, Richard Conrey, John R. Wood, R. Blaine McCleskey, William E. Keller, Behnaz Hosseini, Jefferson D.G. Hungerford
Yellowstone's Old Faithful Geyser shut down by a severe 13th century drought
To characterize eruption activity of the iconic Old Faithful Geyser in Yellowstone National Park over past centuries, we obtained 41 new radiocarbon dates of mineralized wood preserved in the mound of silica that precipitated from erupted waters. Trees do not grow on active geyser mounds, implying that trees grew on the Old Faithful Geyser mound during a protracted period of eruption quiescence. R
Authors
Shaul Hurwitz, John King, Gregory T. Pederson, Justin Martin, David Damby, Michael Manga, Jefferson Hungerford, Sara Peek
Dating silica sinter (geyserite): A cautionary tale
We describe a new effort to date hydrothermal silica sinter deposits (geyserite) from the Upper Geyser Basin of Yellowstone National Park using 14C of co-deposited organic matter, U-series and cosmogenic 10Be methods. A majority of the samples were collected from stratigraphic sections, mainly at Riverside, Giant, and Castle Geysers. Ages obtained from 41 14C analyses range from modern to 12.1 cal
Authors
Dakota M. Churchill, Michael Manga, Shaul Hurwitz, Sara Peek, Joseph Licciardi, James B. Paces
Hydrothermal activity in the southwest Yellowstone Plateau Volcanic Field
In the past two decades, the U.S. Geological Survey and the National Park Service have studied hydrothermal activity across the Yellowstone Plateau Volcanic Field (YPVF) to improve the understanding of the magmatic-hydrothermal system and to provide a baseline for detecting future anomalous activity. In 2017 and 2018 we sampled water and gas over a large area in the southwest YPVF and used Landsat
Authors
Shaul Hurwitz, R. Blaine McCleskey, Deborah Bergfeld, Sara Peek, David Susong, David A. Roth, Jefferson Hungerford, Erin B White, Lauren Harrison, Behnaz Hosseini, R. Greg Vaughan, Andrew G. Hunt, James B. Paces
Coral skeleton δ15N as a tracer of historic nutrient loading to a coral reef in Maui, Hawaii
Excess nutrient loading to nearshore environments has been linked to declining water quality and ecosystem health. Macro-algal blooms, eutrophication, and reduction in coral cover have been observed in West Maui, Hawaii, and linked to nutrient inputs from coastal submarine groundwater seeps. Here, we present a forty-year record of nitrogen isotopes (δ15N) of intra-crystalline coral skeletal organi
Authors
Joseph Murray, Nancy G. Prouty, Sara E. Peek, Adina Paytan
Science and Products
- Data
Mineralogy, strontium (87Sr/86Sr), oxygen (18O/16O) and carbon (13C/12C) isotope composition, elemental concentrations, and U-Th disequilibrium ages for travertine deposits from various locations in Yellowstone National Park, USA
Chemical changes in hot springs, as recorded by thermal waters and their mineral deposits, provide a window into the evolution of Yellowstone’s postglacial hydrothermal system. Travertine precipitated from thermal waters provide a record of chemical changes through time because they can be dated using U-series disequilibrium geochronology. These temporal data, along with measured radiogenic 87Sr/8Chemical and isotopic composition of gas, water, and solids from the 2019-2020 water lake in Halema’uma’u Crater, Kīlauea Volcano, Hawaii
Following the 2018 eruption of Kīlauea Volcano (Neal et al, 2019) and the subsequent collapse of the Halema’uma’u crater, groundwater gradually seeped into the newly-deepened crater (Nadeau and others, 2020). Water was first observed in the crater on 7/26/2019, and the water level increased over time until 12/20/2020, when the crater again filled with lava, vaporizing the lake. In the intervening - Publications
Geochemistry and fluxes of gases from hydrothermal features at Newberry Volcano, Oregon, USA
We present the chemical and isotopic compositions of gases and fluxes of CO2 from the hydrothermal features of Newberry Volcano, a large composite volcano located in Oregon's Cascade Range with a summit caldera that hosts two lakes, Paulina and East Lakes. Gas samples were collected from 1982 to 2021 from Paulina Hot Springs (PHS) on the shore of Paulina Lake, East Lake Hot Springs (ELHS) on the sAuthorsJennifer L. Lewicki, William C. Evans, Steven E. Ingebritsen, Laura E. Clor, Peter J. Kelly, Sara Peek, Robert A. Jensen, Andrew HuntMechanisms for retention of low molecular weight organic carbon varies with soil depth at a coastal prairie ecosystem
Though primary sources of carbon (C) to soil are plant inputs (e.g., rhizodeposits), the role of microorganisms as mediators of soil organic carbon (SOC) retention is increasingly recognized. Yet, insufficient knowledge of sub-soil processes complicates attempts to describe microbial-driven C cycling at depth as most studies of microbial-mineral-C interactions focus on surface horizons. We leveragAuthorsJack McFarland, Corey Lawrence, Courtney Creamer, Marjorie S. Schulz, Christopher H. Conaway, Sara Peek, Mark Waldrop, Sabrina N. Sevilgen, Monica HawStable isotopes provide insight into sources and cycling of N compounds in the Sacramento-San Joaquin Delta, California, USA
River deltas and their diverse array of aquatic environments are increasingly impacted by anthropogenic inputs of nitrogen (N). These inputs can alter the N biogeochemistry of these systems and promote undesirable phenomena including harmful algae blooms and invasive aquatic macrophytes. To examine N sources and biogeochemical processes in the Sacramento-San Joaquin Delta, a river delta located inAuthorsJoseph K. Fackrell, Tamara E. C. Kraus, Megan B. Young, Carol Kendall, Sara PeekThe structure and volume of large geysers in Yellowstone National Park, USA and the mineralogy and chemistry of their silica sinter deposits
Siliceous sinter is formed by biogenic and abiogenic opal deposition around hot springs and geysers. Using Structure-from-Motion photogrammetry we generated three-dimensional models of Giant and Castle Geysers from the Upper Geyser Basin of Yellowstone National Park. We use these models to calculate an approximate mass of sinter for each (~2 and ~ 5 kton, respectively) and estimate a range of plauAuthorsDakota Churchill, Michael Manga, Shaul Hurwitz, Sara Peek, David Damby, Richard Conrey, John R. Wood, R. Blaine McCleskey, William E. Keller, Behnaz Hosseini, Jefferson D.G. HungerfordYellowstone's Old Faithful Geyser shut down by a severe 13th century drought
To characterize eruption activity of the iconic Old Faithful Geyser in Yellowstone National Park over past centuries, we obtained 41 new radiocarbon dates of mineralized wood preserved in the mound of silica that precipitated from erupted waters. Trees do not grow on active geyser mounds, implying that trees grew on the Old Faithful Geyser mound during a protracted period of eruption quiescence. RAuthorsShaul Hurwitz, John King, Gregory T. Pederson, Justin Martin, David Damby, Michael Manga, Jefferson Hungerford, Sara PeekDating silica sinter (geyserite): A cautionary tale
We describe a new effort to date hydrothermal silica sinter deposits (geyserite) from the Upper Geyser Basin of Yellowstone National Park using 14C of co-deposited organic matter, U-series and cosmogenic 10Be methods. A majority of the samples were collected from stratigraphic sections, mainly at Riverside, Giant, and Castle Geysers. Ages obtained from 41 14C analyses range from modern to 12.1 calAuthorsDakota M. Churchill, Michael Manga, Shaul Hurwitz, Sara Peek, Joseph Licciardi, James B. PacesHydrothermal activity in the southwest Yellowstone Plateau Volcanic Field
In the past two decades, the U.S. Geological Survey and the National Park Service have studied hydrothermal activity across the Yellowstone Plateau Volcanic Field (YPVF) to improve the understanding of the magmatic-hydrothermal system and to provide a baseline for detecting future anomalous activity. In 2017 and 2018 we sampled water and gas over a large area in the southwest YPVF and used LandsatAuthorsShaul Hurwitz, R. Blaine McCleskey, Deborah Bergfeld, Sara Peek, David Susong, David A. Roth, Jefferson Hungerford, Erin B White, Lauren Harrison, Behnaz Hosseini, R. Greg Vaughan, Andrew G. Hunt, James B. PacesCoral skeleton δ15N as a tracer of historic nutrient loading to a coral reef in Maui, Hawaii
Excess nutrient loading to nearshore environments has been linked to declining water quality and ecosystem health. Macro-algal blooms, eutrophication, and reduction in coral cover have been observed in West Maui, Hawaii, and linked to nutrient inputs from coastal submarine groundwater seeps. Here, we present a forty-year record of nitrogen isotopes (δ15N) of intra-crystalline coral skeletal organiAuthorsJoseph Murray, Nancy G. Prouty, Sara E. Peek, Adina Paytan - News