Summit flats are low relief, gently sloping landforms common in periglacial mountain environments. Apart from at their edges where summit flats are truncated by glacial headwalls, and at their crests where isolated tors are occasionally present, bedrock is typically mantled on a summit flat by a continuous layer of regolith. This study applied ground penetrating radar (GPR) to survey the thickness of regolith on a summit flat in the Uinta Mountains (Utah, USA). More than 500 m of GPR data were collected along transects extending from the edge of the summit flat to the crest, as well as adjacent to a deep soil pit. Results indicate that the regolith thickness is quite variable, with a mean of 91 ± 38 cm. Because the ground surface of the summit flat is notably smooth, the variability in thickness is a consequence of irregularities in the bedrock surface at depth, which is significantly rougher. Recognition that regolith thickness can vary considerably beneath an alpine summit flat has implications for soil formation, carbon storage, and the transmission and storage of shallow groundwater, as well as evolutionary models for periglacial mountain landscapes. 
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                            Envisioning and Sustaining Science at Summit Station, Greenland
                        
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            Pool, Robert (Ed.)On October 10-11, 2023, the National Academies of Sciences, Engineering, and Medicine hosted the U.S. Research Data Summit at the National Academy of Sciences Building in Washington, DC. The summit was undertaken by a planning committee organized under the U.S. National Committee for CODATA. The summit was informed by input from 29 organizations, including leaders from federal government agencies, the private sector, public and nonprofit organizations, and research institutions. This publication summarizes the presentations and discussion of the summit.more » « less
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            The 2008–2018 lava lake at the summit of Kīlauea marked the longest sustained period of lava lake activity at the summit in decades and provided a new opportunity for observing and understanding lava lake behavior. This paper cover the basic chronology of the eruption, rich historical background, observations and measurements of lake activity, hydrological setting, as well as geophysical and other monitoring data that tracked the activity. The primary focus is the 2008–2018 lava lake activity, ending with the draining of the lake in May 2018. The 2018 summit collapse events that followed the lake draining, and which dramatically altered the topography of the summit region, are published elsewhere.more » « less
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