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Beryllium‐10 surface exposure dating of glacial successions in the Central Alaska Range ... The new data suggest that post‐depositional geological processes limit the usefulness of 10 Be methods to the latter part (≤60 ka) of the late Quaternary in central Alaska. Ages on Healy and younger landforms cluster well, with the …Web
Over millennial timescales, inventories of meteoric 10 Be in non-eroding soil profiles of known ages, developed on river terraces, moraine deposits, or bedrock, provide site-specific depositional ...Web
Present day accumulation rates of nine sediment cores recovered during the Russian-German Expedition Transdrift II (1994) from the shelf area of the Laptev Sea were determined by 210Pbex dating and vary from 0.05 to 0.24 g cm-2 a-1. In addition, the sedimentation rates during the isotopic stages 2, 3 and 5 of the sediment core PS 2471-4 …Web
The 10 Be depositional flux has been estimated from various sediment cores in the Pacific and the Atlantic Ocean mainly to understand the past variation of depositional flux resulting from the ...Web
Based on 10 Be inventories of our river terraces, the calculated long-term 10 Be depositional fluxes vary from 0.32 to 0.49 Â 10 6 at/cm 2 /yr in the Taiwan orogen.Web
Beryllium-10 (10 Be) has proven to be an essential tool for building chronology and understanding millennial-scale surface processes.Measurements in both the water column and authigenic fractions from various archives (such as surface sediments and Fe-Mn crusts) have provided valuable information on processes regulating Be isotopic …Web
The main input parameters for the model calculations are water exchange time between the two boxes (T ex), and vertical mass rain rates in both boxes.By assuming that steady state is reached (when the production of 10 Be (230 Th) equals the total sedimentation flux in both boxes), the quotient of depositional flux (Fa) of 10 Be (230 …Web
Using an incorrect record of the Earth's magnetic field to normalize the depositional 10 Be flux could cause misinterpretations of paleobioproductivity or/and …Web
The sedimentation rate calculated by changing the 10 Be depositional flux rate from 1.5 to 2.5 × 10 −2 atoms.cm −2.s −1 shows large variation, indicating the choice of appropriate 10 Be depositional flux rate for the region. Additionally, being the first meteoric beryllium-10 measurements using AURiS, we have also discussed and reported ...Web
@article{osti_5483555, title = {Atmospheric depositional characteristics of Beryllium 7 and Lead 210 along Southeastern ia coast}, author = {Todd, J F and Wong, G T.F. and Olsen, C R and Larsen, I L}, abstractNote = {Atmospheric depositional fluxes of {sup 7}Be and {sup 210}Pb were measured simultaneously in wet-only and bulk deposition over a …Web
Here, 7 Be and 10 Be in the Sichuan Basin of China were simultaneously measured by AMS, and after removing the 10 Be interference of resuspended dust, a 10 Be/ 7 Be record with the high-precision daily resolution for a whole year was obtained. Furthermore, the hard-to-capture local stratospheric air intrusion can cause rapid …Web
Abstract. 7Be and 210Pb air concentration and depositional flux data provide key information on the origins and movements of air masses, as well as atmospheric deposition processes and ... Beryllium-10 and beryllium-7 have been measured in monthly precipitation samples at a high (Jungfraujoch, 46.32°N 7.59°E, 3580 m) and a low ...Web
Beryllium-10 in ice provides a valuable proxy of solar activity. However, complex production pathways, atmospheric transport, and deposition processes impede …Web
Geology (2015) 43 (12): 1111–1112. Banded iron formations (BIFs) have been at the center of many debates in geology, especially regarding the early (i.e., Archean and Paleoproterozoic) Earth and its surface environments. BIFs are chemical sedimentary rocks that have an anomalously high iron content (>15 wt% Fe) and typically contain layers of ...Web
Beryllium-10 and beryllium-7 have been measured in monthly precipitation samples at a high (Jungfraujoch, 46.32°N 7.59°E, 3580 m) and a low (Dübendorf, 47.25°N 8.27°E, 440 m) altitude station ...Web
This work comprises three novel applications of in situ- and meteoric-produced beryllium-10 (Be-10) in East Antarctica. Sampled deposits cover a wide spatiotemporal transect through the Dry Valleys, from an inland, middle elevation location of Quaternary age, to a mid-valley, high elevation location of Miocene age, and finally to an offshore, submarine location of …Web
Beryllium 10. The heaviest bound beryllium isotope 14Be was identified early on as a halo nucleus based on radii deduced in measurements of interaction and reaction cross …Web
In this study a highly resolved Beryllium-10-record from a rapidly accumulating sediment core located in the Southern Cape Basin (ODP Leg 177 Site 1089) is presented. To extract the global 10 Be-production signal from the sedimentary record a dedicated correction procedure is applied. First, sediment redistribution is quantified by …Web
Banded iron formation (BIF) is a lithological term applied to a thinly bedded or laminated chemical sedimentary rock consisting of successive layers of fine-grained quartz, iron oxides, carbonates, and/or silicates, typically containing 20–40% of iron and 40–50% of silica (Trendall 2002; Klein 2005 ).Web
Investigations of the atmospheric fallout of 7 Be and 210 Pb in many places around the globe indicate that there are seasonal variations on the depositional fluxes of these nuclides: high in winter in a few places, while in most places the high occurs in spring. However, these earlier studies did not address quantitatively the corresponding seasonal …Web
Highlights Different depositional processes are found in the cosmogenic 7 Be and 10 Be fluxes. A cleaning mechanism can be found at all three sites. 7 Be at low altitude Swiss site shows a tropospherical depositional pattern. 10 Be in Swiss low altitude site shows tropospherical and stratospherical deposition. The beryllium deposition pattern at …Web
The analysis of cosmogenic beryllium-10 provides a geochemical method for constraining the accumulation-rate history at Taylor Dome. High-resolution measurements were made in shallow firn cores and snow pits to determine the relationship among beryllium-10 concentrations, wet and dry deposition mechanisms, and snow …Web
Beryllium-10 deposition rates have been measured in ice cores in Greenland and elsewhere in many studies (these are reviewed and compiled in Adolphi et al., 2018) and display significant centennial-scale variability during the time period …Web
Section snippets The model. A simple steady-state two-box model is applied to calculate the depositional flux of 10 Be and 230 Th into deep-sea sediments (Broecker and Peng, 1982; Rutsch et al., 1995; Asmus et al., 1999). The advantage of this model is its small number of parameters compared to more complex GCM models recently applied …Web
Beryllium-10 (10 Be) is produced in the atmosphere by the interaction of cosmic-ray particles with oxygen and nitrogen (Dunai, 2010; ... Authigenic 10 Be has been used to date marine sediment cores using 10 Be depositional flux (Tanaka et al., 1977; Tanaka and Inoue, 1979), ...Web
The monthly 7 Be atmospheric deposition flux ranged from 1 to 67 mBq/cm 2 (Table 1), with a 7-year average monthly flux of 21.6 ± 0.3 mBq/cm 2.The calculated 7 Be atmospheric depositional running inventory ranged from 36 to 144 mBq/cm 2 (Table 1), with an average of 65 ± 2 mBq/cm 2.The atmospheric deposition fluxes of 7 Be were …Web
