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1. Calibrating a long-term meteoric ¹⁰Be delivery rate into eroding western US glacial deposits by comparing meteoric and in situ produced ¹⁰Be depth profiles

   https://doi.org/10.5194/gchron-2-411-2020  

   Clow, Travis ; Willenbring, Jane K. ; Schaller, Mirjam ; Blum, Joel D. ; Christl, Marcus ; Kubik, Peter W. ; von Blanckenburg, Friedhelm ( January 2020 , Geochronology)

   null (Ed.)

   Abstract. Meteoric 10Be (10Bemet) concentrations insoil profiles have great potential as a geochronometer and a tracer of Earthsurface processes, particularly in fine-grained soils lacking quartz thatwould preclude the use of in situ produced 10Be (10Bein situ). Oneprerequisite for using this technique for accurately calculating rates anddates is constraining the delivery, or flux, of 10Bemet to a site.However, few studies to date have quantified long-term (i.e., millennial)delivery rates, and none have determined a delivery rate for an erodingsoil. In this study, we compared existing concentrations of 10Bein situ with new measurements of 10Bemet in eroding soils sampledfrom the same depth profiles to calibrate a long-term 10Bemetdelivery rate. We did so on the Pinedale (∼ 21–25 kyr) and BullLake (∼ 140 kyr) glacial moraines at Fremont Lake, Wyoming(USA), where age, grain sizes, weathering indices, and soil properties areknown, as are erosion and denudation rates calculated from 10Bein situ. After ensuring sufficient beryllium retention in each profile,solving for the delivery rate of 10Bemet, and normalizing forpaleomagnetic and solar intensity variations over the Holocene, we calculate10Bemet fluxes of 1.46 (±0.20) × 106 atoms cm−2 yr−1 and 1.30 (±0.48) × 106 atoms cm−2 yr−1 tothe Pinedale and Bull Lake moraines, respectively, and compare these valuesto two widely used 10Bemet delivery rate estimation methods thatsubstantially differ for this site. Accurately estimating the 10Bemetflux using these methods requires a consideration of spatial scale andtemporally varying parameters (i.e., paleomagnetic field intensity, solarmodulation) to ensure the most realistic estimates of10Bemet-derived erosion rates in future studies. 

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2. Relationship between meteoric ¹⁰Be and NO₃⁻ concentrations in soils along Shackleton Glacier, Antarctica

   https://doi.org/10.5194/esurf-9-1363-2021  

   Diaz, Melisa A. ; Corbett, Lee B. ; Bierman, Paul R. ; Adams, Byron J. ; Wall, Diana H. ; Hogg, Ian D. ; Fierer, Noah ; Lyons, W. Berry ( January 2021 , Earth Surface Dynamics)

   Abstract. Outlet glaciers that flow through the Transantarctic Mountains (TAM) experienced changes in ice thickness greater than other coastal regions of Antarctica during glacial maxima. As a result, ice-free areas that are currently exposed may have been covered by ice at various points during the Cenozoic, complicating our understanding of ecological succession in TAM soils. Our knowledge of glacial extent on small spatial scales is limited for the TAM, and studies of soil exposure duration and disturbance, in particular, are rare. We collected surface soil samples and, in some places, depth profiles every 5 cm to refusal (up to 30 cm) from 11ice-free areas along Shackleton Glacier, a major outlet glacier of the EastAntarctic Ice Sheet. We explored the relationship between meteoric 10Be and NO3- in these soils as a tool for understanding landscape disturbance and wetting history and as exposure proxies. Concentrations of meteoric 10Be spanned more than an order of magnitude across the region (2.9×108 to 73×108 atoms g−1) and are among the highest measured in polar regions. The concentrations of NO3- were similarly variable and ranged from ∼1 µg g−1 to 15 mg g−1. In examining differences and similarities in the concentrations of 10Be and NO3- with depth, we suggest that much of the southern portion of the Shackleton Glacier region has likely developed under a hyper-arid climate regime with minimal disturbance. Finally, we inferred exposure time using 10Be concentrations. This analysis indicates that the soils we analyzed likelyrange from recent exposure (following the Last Glacial Maximum) to possibly>6 Myr. We suggest that further testing and interrogation of meteoric 10Be and NO3- concentrations and relationships in soils can provide important information regarding landscape development, soil evolution processes, and inferred exposure durations of surfaces in the TAM. 

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3. Comparison of basin-scale in situ and meteoric ¹⁰Be erosion and denudation rates in felsic lithologies across an elevation gradient at the George River, northeast Tasmania, Australia

   https://doi.org/10.5194/gchron-4-153-2022  

   VanLandingham, Leah A. ; Portenga, Eric W. ; Lefroy, Edward C. ; Schmidt, Amanda H. ; Bierman, Paul R. ; Hidy, Alan J. ( January 2022 , Geochronology)

   Abstract. Long-term erosion rates in Tasmania, at the southern end of Australia's Great Dividing Range, are poorly known; yet, this knowledge is critical for making informed land-use decisions and improving the ecological health of coastal ecosystems. Here, we present quantitative, geologically relevant estimates of erosion rates for the George River basin, in northeast Tasmania, based on in situ-produced 10Be (10Bei) measured from stream sand at two trunk channel sites and seven tributaries (mean: 24.1±1.4 Mgkm-2yr-1; 1σ). These new10Bei-based erosion rates are strongly related to elevation, which appears to control mean annual precipitation and temperature,suggesting that elevation-dependent surface processes influence rates of erosion in northeast Tasmania. Erosion rates are not correlated with slopein contrast to erosion rates along the mainland portions of Australia's Great Dividing Range. We also extracted and measured meteoric 10Be(10Bem) from grain coatings of sand-sized stream sediment at each site, which we normalize to measured concentrations of reactive 9Beand use to estimate 10Bem-based denudation rates for the George River. 10Bem/9Bereac denudation ratesreplicate 10Bei erosion rates within a factor of 3 but are highly sensitive to the value of 9Be that is found in bedrock(9Beparent), which was unmeasured in this study. 10Bem/9Bereac denudation rates seem sensitive to recentmining, forestry, and agricultural land use, all of which resulted in widespread topsoil disturbance. Our findings suggest that10Bem/9Bereac denudation metrics will be most useful in drainage basins that are geologically homogeneous, where recentdisturbances to topsoil profiles are minimal, and where 9Beparent is well constrained. 

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4. Spatial and temporal replicability of meteoric and in situ 10 Be concentrations in fluvial sediment

   https://doi.org/10.1002/esp.4205  

   Sosa Gonzalez, Veronica ; Schmidt, Amanda H. ; Bierman, Paul R. ; Rood, Dylan H. ( August 2017 , Earth Surface Processes and Landforms)
5. Susquehanna Shale Hills Critical Zone Observatory: Shale Hills in the Context of Shaver’s Creek Watershed

   https://doi.org/10.2136/vzj2018.04.0092  

   Brantley, Susan L. ; White, Tim ; West, Nicole ; Williams, Jennifer Z. ; Forsythe, Brandon ; Shapich, Dan ; Kaye, Jason ; Lin, Henry ; Shi, Yuning ; Kaye, Margot ; et al ( January 2018 , Vadose Zone Journal)