[{"awards": "2336354 Juarez Rivera, Marisol; 1937748 Sumner, Dawn", "bounds_geometry": ["POLYGON((161 -77.5,161.3 -77.5,161.6 -77.5,161.9 -77.5,162.2 -77.5,162.5 -77.5,162.8 -77.5,163.1 -77.5,163.4 -77.5,163.7 -77.5,164 -77.5,164 -77.55,164 -77.6,164 -77.65,164 -77.7,164 -77.75,164 -77.8,164 -77.85,164 -77.9,164 -77.95,164 -78,163.7 -78,163.4 -78,163.1 -78,162.8 -78,162.5 -78,162.2 -78,161.9 -78,161.6 -78,161.3 -78,161 -78,161 -77.95,161 -77.9,161 -77.85,161 -77.8,161 -77.75,161 -77.7,161 -77.65,161 -77.6,161 -77.55,161 -77.5))"], "date_created": "Tue, 29 Jul 2025 00:00:00 GMT", "description": "Gas bubbles directly influence the macromorphology of benthic microbial mats resulting in preservable biosedimentary structures. This study characterizes the morphology and distribution of microbial mats growing in gas\u2010supersaturated, perennially ice\u2010covered lakes Fryxell, Joyce, and Hoare of the McMurdo Dry Valleys of Antarctica. Photosynthetic benthic mats within the gas\u2010supersaturated zone trap oxygen\u2010rich bubbles and become buoyant, tearing off the bottom as \u201cliftoff mats.\u201d These liftoff mats form a succession of morphologies starting with bubble\u2010induced deformation of flat mats into tent, ridge, and finger liftoff mat. With progressive deformation, mats tear, forming sheet liftoff, while multiple cycles of deformation and tearing transform sheet into strip liftoff. Some mats detach from the substrate and float to the underside of the ice. The depth range of the liftoff zone has varied over time at each lake. Downslope expansion of bubble formation brings previously bubble\u2010free, deep\u2010water pinnacle mats into the liftoff zone. When the liftoff zone shallows, liftoff mats at the deeper end deflate and can become scaffolding for additional mat growth. The superposition and relative orientation of liftoff and pinnacle mats can be used to track the maximum depth of the liftoff zone and changes in gas saturation state in these lakes through time. Our results demonstrate that gas bubbles, even when they are transitory, can exert a significant impact on the morphology of microbial mats at larger scales. This provides a way to identify similar structures and gas supersaturated environments in the biosedimentary record.", "east": 164.0, "geometry": ["POINT(162.5 -77.75)"], "keywords": "Antarctica; Antarctic Lake-level; Cryosphere; McMurdo Dry Valleys; Microbial Mat; Trapped Air Bubbles", "locations": "Antarctica; McMurdo Dry Valleys", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Integrated System Science", "persons": "Sumner, Dawn; Juarez Rivera, Marisol; Mackey, Tyler; Hawes, Ian", "project_titles": "RAPID: Is Biomass Mobilization at Ice-covered Lake Fryxell, Antarctica reaching a Critical Threshold?; Seasonal Primary Productivity and Nitrogen Cycling in Photosynthetic Mats, Lake Fryxell, McMurdo Dry Valleys", "projects": [{"proj_uid": "p0010219", "repository": "USAP-DC", "title": "Seasonal Primary Productivity and Nitrogen Cycling in Photosynthetic Mats, Lake Fryxell, McMurdo Dry Valleys"}, {"proj_uid": "p0010467", "repository": "USAP-DC", "title": "RAPID: Is Biomass Mobilization at Ice-covered Lake Fryxell, Antarctica reaching a Critical Threshold?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Morphology and Distribution of Bubble\u2010Supported Microbial Mats From Ice\u2010Covered Antarctic Lakes", "uid": "601959", "west": 161.0}, {"awards": "0124014 Hall, Brenda", "bounds_geometry": ["POLYGON((163.053 -77.599,163.0741 -77.599,163.0952 -77.599,163.1163 -77.599,163.1374 -77.599,163.1585 -77.599,163.1796 -77.599,163.2007 -77.599,163.2218 -77.599,163.24290000000002 -77.599,163.264 -77.599,163.264 -77.60130000000001,163.264 -77.6036,163.264 -77.6059,163.264 -77.6082,163.264 -77.6105,163.264 -77.61280000000001,163.264 -77.6151,163.264 -77.6174,163.264 -77.6197,163.264 -77.622,163.24290000000002 -77.622,163.2218 -77.622,163.2007 -77.622,163.1796 -77.622,163.1585 -77.622,163.1374 -77.622,163.1163 -77.622,163.0952 -77.622,163.0741 -77.622,163.053 -77.622,163.053 -77.6197,163.053 -77.6174,163.053 -77.6151,163.053 -77.61280000000001,163.053 -77.6105,163.053 -77.6082,163.053 -77.6059,163.053 -77.6036,163.053 -77.60130000000001,163.053 -77.599))"], "date_created": "Wed, 09 Jul 2025 00:00:00 GMT", "description": "Physical and chemical properties of sediment cores from Lake Fryxell, Antarctica, provide a means of reconstructing past paleoenvironmental, water-level, and water-source changes over the last 60,000 years. This dataset includes stable isotope (O, C), radiocarbon, U-series, sedimentological, and loss-on-ignition data. The oxygen data relate primarily to water-source changes in the lake basin. Carbon (both stable and radioactive) isotopes are influenced heavily by lake stratification and depth of the photic zone. The data record surface level changes of Lake Fryxell over the past 60,000 years. In addition, the dated sediments constrain the Ross Sea ice sheet to east of (seaward of) the lake through that entire time. Finally, stable oxygen isotopes document water source changes switching from local alpine glacier meltwater to Ross Sea ice sheet meltwater and then back to local glacier meltwater.", "east": 163.264, "geometry": ["POINT(163.1585 -77.6105)"], "keywords": "Antarctica; Cryosphere; Dry Valleys; Lake Fryxell; Paleoclimate; Radiocarbon; Ross Ice Sheet; Ross Sea; Stable Isotopes; U", "locations": "Lake Fryxell; Ross Sea; Ross Ice Sheet; Dry Valleys; Antarctica", "north": -77.599, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Hall, Brenda; Whittaker, Thomas", "project_titles": "Collaborative Research: Millennial-scale fluctuations of Dry Valleys lakes: Implications for regional climate variability and the interhemispheric (a)synchrony of climate change", "projects": [{"proj_uid": "p0010519", "repository": "USAP-DC", "title": "Collaborative Research: Millennial-scale fluctuations of Dry Valleys lakes: Implications for regional climate variability and the interhemispheric (a)synchrony of climate change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.622, "title": "Lake Fryxell Sediment Core Data", "uid": "601955", "west": 163.053}, {"awards": "2336354 Juarez Rivera, Marisol; 1937748 Sumner, Dawn", "bounds_geometry": ["POINT(163.1146 -77.6078)"], "date_created": "Wed, 02 Oct 2024 00:00:00 GMT", "description": "This dataset contains measurements of microbial mat thickness and number of laminae from Lake Fryxell, McMurdo Dry Valleys, Antarctica. Holes were melted through the ice cover of Lake Fryxell, which allowed tethered divers to collect benthic microbial mats (non-liftoff and liftoff) and microbial mats at the ice-water interface (float mats). Benthic non-liftoff and liftoff mat samples were collected from 4.3 m (n=4), 6.1 m (n=4), and 7.9 m (n=4) depths. Float mats were collected from the ice-water interface above 4.3 m (n=4), 6.1 m (n=4), and 7.9 m (n=5) depths. The mats were dissected along vertical cross sections in the field to measure mat thickness and number of laminae. Additional funding for this work was provided by the NASA Solar System Workings Program (Award #80NSSC22K0709).", "east": 163.1146, "geometry": ["POINT(163.1146 -77.6078)"], "keywords": "Antarctica; Cryosphere; Dry Valleys; Lake Fryxell; Laminae; Microbial Mat; Thickness", "locations": "Antarctica; Lake Fryxell; Dry Valleys; Antarctica", "north": -77.6078, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Integrated System Science", "persons": "Juarez Rivera, Marisol; Mackey, Tyler; Hawes, Ian; Paul, Ann; Sumner, Dawn", "project_titles": "RAPID: Is Biomass Mobilization at Ice-covered Lake Fryxell, Antarctica reaching a Critical Threshold?; Seasonal Primary Productivity and Nitrogen Cycling in Photosynthetic Mats, Lake Fryxell, McMurdo Dry Valleys", "projects": [{"proj_uid": "p0010219", "repository": "USAP-DC", "title": "Seasonal Primary Productivity and Nitrogen Cycling in Photosynthetic Mats, Lake Fryxell, McMurdo Dry Valleys"}, {"proj_uid": "p0010467", "repository": "USAP-DC", "title": "RAPID: Is Biomass Mobilization at Ice-covered Lake Fryxell, Antarctica reaching a Critical Threshold?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.6078, "title": "Lake Fryxell 2022-2023 benthic microbial mat thickness and number of laminae", "uid": "601839", "west": 163.1146}]

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Dataset Title/Abstract/Map	NSF Award(s)	Date Created	PIs / Scientists	Project Links	Abstract	Bounds Geometry	Geometry	Selected	Visible
Morphology and Distribution of Bubble‐Supported Microbial Mats From Ice‐Covered Antarctic Lakes	2336354 1937748	2025-07-29	Sumner, Dawn; Juarez Rivera, Marisol; Mackey, Tyler; Hawes, Ian	Seasonal Primary Productivity and Nitrogen Cycling in Photosynthetic Mats, Lake Fryxell, McMurdo Dry Valleys RAPID: Is Biomass Mobilization at Ice-covered Lake Fryxell, Antarctica reaching a Critical Threshold?	Gas bubbles directly influence the macromorphology of benthic microbial mats resulting in preservable biosedimentary structures. This study characterizes the morphology and distribution of microbial mats growing in gas‐supersaturated, perennially ice‐covered lakes Fryxell, Joyce, and Hoare of the McMurdo Dry Valleys of Antarctica. Photosynthetic benthic mats within the gas‐supersaturated zone trap oxygen‐rich bubbles and become buoyant, tearing off the bottom as “liftoff mats.” These liftoff mats form a succession of morphologies starting with bubble‐induced deformation of flat mats into tent, ridge, and finger liftoff mat. With progressive deformation, mats tear, forming sheet liftoff, while multiple cycles of deformation and tearing transform sheet into strip liftoff. Some mats detach from the substrate and float to the underside of the ice. The depth range of the liftoff zone has varied over time at each lake. Downslope expansion of bubble formation brings previously bubble‐free, deep‐water pinnacle mats into the liftoff zone. When the liftoff zone shallows, liftoff mats at the deeper end deflate and can become scaffolding for additional mat growth. The superposition and relative orientation of liftoff and pinnacle mats can be used to track the maximum depth of the liftoff zone and changes in gas saturation state in these lakes through time. Our results demonstrate that gas bubbles, even when they are transitory, can exert a significant impact on the morphology of microbial mats at larger scales. This provides a way to identify similar structures and gas supersaturated environments in the biosedimentary record.	["POLYGON((161 -77.5,161.3 -77.5,161.6 -77.5,161.9 -77.5,162.2 -77.5,162.5 -77.5,162.8 -77.5,163.1 -77.5,163.4 -77.5,163.7 -77.5,164 -77.5,164 -77.55,164 -77.6,164 -77.65,164 -77.7,164 -77.75,164 -77.8,164 -77.85,164 -77.9,164 -77.95,164 -78,163.7 -78,163.4 -78,163.1 -78,162.8 -78,162.5 -78,162.2 -78,161.9 -78,161.6 -78,161.3 -78,161 -78,161 -77.95,161 -77.9,161 -77.85,161 -77.8,161 -77.75,161 -77.7,161 -77.65,161 -77.6,161 -77.55,161 -77.5))"]	["POINT(162.5 -77.75)"]	false	false
Lake Fryxell Sediment Core Data	0124014	2025-07-09	Hall, Brenda; Whittaker, Thomas	Collaborative Research: Millennial-scale fluctuations of Dry Valleys lakes: Implications for regional climate variability and the interhemispheric (a)synchrony of climate change	Physical and chemical properties of sediment cores from Lake Fryxell, Antarctica, provide a means of reconstructing past paleoenvironmental, water-level, and water-source changes over the last 60,000 years. This dataset includes stable isotope (O, C), radiocarbon, U-series, sedimentological, and loss-on-ignition data. The oxygen data relate primarily to water-source changes in the lake basin. Carbon (both stable and radioactive) isotopes are influenced heavily by lake stratification and depth of the photic zone. The data record surface level changes of Lake Fryxell over the past 60,000 years. In addition, the dated sediments constrain the Ross Sea ice sheet to east of (seaward of) the lake through that entire time. Finally, stable oxygen isotopes document water source changes switching from local alpine glacier meltwater to Ross Sea ice sheet meltwater and then back to local glacier meltwater.	["POLYGON((163.053 -77.599,163.0741 -77.599,163.0952 -77.599,163.1163 -77.599,163.1374 -77.599,163.1585 -77.599,163.1796 -77.599,163.2007 -77.599,163.2218 -77.599,163.24290000000002 -77.599,163.264 -77.599,163.264 -77.60130000000001,163.264 -77.6036,163.264 -77.6059,163.264 -77.6082,163.264 -77.6105,163.264 -77.61280000000001,163.264 -77.6151,163.264 -77.6174,163.264 -77.6197,163.264 -77.622,163.24290000000002 -77.622,163.2218 -77.622,163.2007 -77.622,163.1796 -77.622,163.1585 -77.622,163.1374 -77.622,163.1163 -77.622,163.0952 -77.622,163.0741 -77.622,163.053 -77.622,163.053 -77.6197,163.053 -77.6174,163.053 -77.6151,163.053 -77.61280000000001,163.053 -77.6105,163.053 -77.6082,163.053 -77.6059,163.053 -77.6036,163.053 -77.60130000000001,163.053 -77.599))"]	["POINT(163.1585 -77.6105)"]	false	false
Lake Fryxell 2022-2023 benthic microbial mat thickness and number of laminae	2336354 1937748	2024-10-02	Juarez Rivera, Marisol; Mackey, Tyler; Hawes, Ian; Paul, Ann; Sumner, Dawn	Seasonal Primary Productivity and Nitrogen Cycling in Photosynthetic Mats, Lake Fryxell, McMurdo Dry Valleys RAPID: Is Biomass Mobilization at Ice-covered Lake Fryxell, Antarctica reaching a Critical Threshold?	This dataset contains measurements of microbial mat thickness and number of laminae from Lake Fryxell, McMurdo Dry Valleys, Antarctica. Holes were melted through the ice cover of Lake Fryxell, which allowed tethered divers to collect benthic microbial mats (non-liftoff and liftoff) and microbial mats at the ice-water interface (float mats). Benthic non-liftoff and liftoff mat samples were collected from 4.3 m (n=4), 6.1 m (n=4), and 7.9 m (n=4) depths. Float mats were collected from the ice-water interface above 4.3 m (n=4), 6.1 m (n=4), and 7.9 m (n=5) depths. The mats were dissected along vertical cross sections in the field to measure mat thickness and number of laminae. Additional funding for this work was provided by the NASA Solar System Workings Program (Award #80NSSC22K0709).	["POINT(163.1146 -77.6078)"]	["POINT(163.1146 -77.6078)"]	false	false

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