7Be, 10Be, and 36Cl in precipitation

doi:10.1016/0168-583X(94)96031-3

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms

Volume 92, Issues 1–4, 3 June 1994, Pages 340-344

https://doi.org/10.1016/0168-583X(94)96031-3 Get rights and content

Abstract

We have measured the cosmogenic radionuclides ⁷Be, ¹⁰Be, and ³⁶Cl in mid-latitude precipitation collected in West Lafayette, IN. In the period April 18, 1992 to August 31, 1993, 350 samples were collected. A series of samples was collected through each precipitation event with 3 mm resolution. The ⁷Be/³⁶Cl and ¹⁰Be/³⁶Cl ratios vary by as much as a factor of 60 with a mean ¹⁰Be/³⁶Cl ratio of 9.1. ⁷Be, ¹⁰Be, and ³⁶Cl concentrations through a single event are correlated and typically decrease from high values at the beginning of an event to lower values at the end. Mean concentrations of ⁷Be, ¹⁰Be, and ³⁶Cl are 1.4 × 10⁷, 1.8 × 10⁷, and 0.2 × 10⁷ atoms/l.

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The Cenozoic uplift of the Tibetan Plateau plays an important role in global climate change, basin-mountain geomorphology formation and desertification in western China. As an important component, the Early Pleistocene uplift process and its influence on the northeastern Tibetan Plateau has been controversial for many years. Quaternary synorogenic sediments within the Dunhuang Basin on the northeastern Tibetan Plateau record the details of plateau uplift. Detailed grain size analysis, rock magnetic properties, mudstone ³⁶Cl dating and ⁴⁰Ar/³⁹Ar detrital mica dating were conducted on the Quaternary alluvial-fluvial-lacustrine-aeolian sediments of the Dunhuang Basin. The Aksay section in the southern Dunhuang Basin is dominated by conglomerate, sandstone, siltstone and mudstone. Detrital mica ⁴⁰Ar/³⁹Ar ages show major age populations of 200–160 Ma, 400–200 Ma and 510–430 Ma from the northeastern Altyn Mountains. The results of ³⁶Cl ages and rock magnetic properties show that the Altyn Mountains rapidly uplifted at 1.16 Ma. From 1.16 to 0.80 Ma, the sedimentary environment was stable with two small-scale uplift pulses at ca. 1.03 Ma and 0.98 Ma. After 0.80 Ma, the climate became arid, and the Kumtag Desert formed in the Dunhuang Basin. These multistage uplifts are also widely found in the northeastern Tibetan Plateau. The Early Pleistocene uplift of the Altyn Mountains, corresponding to the Kunhuang Movement, resulted in the northeastern margin of the Tibetan Plateau reaching its present height and climate changeing towards drought in this region.
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Citation Excerpt :
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Citation Excerpt :
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Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms

Abstract

References (12)

Geophys. Res. Lett.

Radiocarbon

Geochim. Cosmochim. Acta

Cited by (42)

Atmospheric deposition of <sup>10</sup>Be in Altzomoni rainfall

Early Pleistocene uplift of the northeastern Tibetan Plateau: Evidence from the Dunhuang Basin, NW China

Inventory and vertical distribution of <sup>137</sup>Cs, <sup>239+240</sup>Pu and <sup>238</sup>Pu in soil from Raivavae and Hiva Oa, two French Polynesian islands in the southern hemisphere

Use of multiple age tracers to estimate groundwater residence times and long-term recharge rates in arid southern Oman

Monthly record of the Cl and <sup>36</sup>Cl fallout rates in a deciduous forest ecosystem in NE France in 2012 and 2013

Plutonium isotope measurements from across continental Australia