Uranium-series disequilibrium as a tool for tracing uranium accumulation zone in altered granite rocks

Levels of lead-210, polonium-210, radium-226, and uranium are reported for 10 plant species (2 conifer, 4 shrub, 3 lichen, and 1 moss species) and soils in northern Saskatchewan. Two localities were studied in each of two regions, one uraniferous, the other not. Nonvascular species showed the highest levels of lead-210, polonium-210, and uranium, and the shrubs, the highest levels of radium-226. The lichen and moss species show no significant difference in accumulation of lead-210 and polonium-210 among regions, reflecting the assumed atmospheric distribution and particulate accumulation of these radionuclides. Seven of eight species for which comparisons could be made showed significant differences in uranium accumulation among regions. High levels in the lichen and moss species suggest that the primary source of uranium in these species is not directly from the soil. In contrast to the other radionuclides, radium-226 only showed significant differences among localities within regions, this being due to high accumulations occurring at one locality in the nonuraniferous region.

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Radiometric dating of hillslope calcrete in the Negev Desert, Israel

South African Journal of Science ◽

10.1590/s0038-23532008000600025 ◽

2008 ◽

Vol 104 (11/12) ◽

Cited By ~ 3

Author(s):

J.C. Vogel ◽

M.A. Geyh

Keyword(s):

Open System ◽

Negev Desert ◽

Radiometric Dating ◽

Jordan Valley ◽

Partial Recrystallization ◽

Uranium Series ◽

Uranium Series Dating

The radiometric dating of calcrete is often problematical because impurities and open system conditions affect the apparent ages obtained. By applying both radiocarbon and uranium-series dating to calcrete in colluvium, it is shown that such conditions can be identified. In correlation with the stratigraphy, it is found that partial recrystallization severely decreases the radiocarbon ages of the upslope and shallower samples further down, whereas incorporation of limestone fragments from bedrock significantly increases the apparent ages of some of the uranium-series samples. It is concluded that the hillslope calcrete at the study site near Sede Beker in the Negev Desert, Israel, mainly developed shortly after 40 kyr ago, at a time when the Jordan Valley was being inundated to form the fossil Lake Lisan. Since their formation would have required higher rainfall than today, the results provide further evidence that the whole region was experiencing an increase in precipitation.

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Description; mineralogical, chemical, and isotopic compositions; petrography; diagenesis; and uranium-series ages of drill cores from the Lagoon of Aitutaki, Cook Islands

Open-File Report ◽

10.3133/ofr88419 ◽

1988 ◽

Cited By ~ 1

Author(s):

J.R. Hein ◽

B.M. Richmond ◽

S.C. Gray ◽

Ruth Hausmann ◽

M.W. Colgan ◽

...

Keyword(s):

Cook Islands ◽

Uranium Series ◽

Isotopic Compositions ◽

Drill Cores

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Radiometric Chronology of Neh–nar Glacier, Kashmir

Journal of Glaciology ◽

10.3189/s0022143000011813 ◽

1982 ◽

Vol 28 (98) ◽

pp. 91-105 ◽

Cited By ~ 1

Author(s):

V. N. Nijampurkar ◽

N. Bhandari ◽

C. P. Vohra ◽

V. Krishnan

Keyword(s):

Average Rate ◽

Component Model ◽

Vertical Profiles ◽

Kashmir Valley ◽

Movement Rate ◽

Accumulation Zone ◽

Core Samples ◽

Surface Samples ◽

Two Component

AbstractSurface and core samples of Neh–nar Glacier in the Kashmir Valley have been analysed for the radionuclides 32Si. 210Pb, 40K, and 137Cs. The lateral and vertical profiles (at an altitude of about 4 140 m) reveal:(1)32Si activity decreasing slowly from the accumulation zone to 4 050 m altitude and then abruptly towards the snout.(2)Five zones of alternating high and low 210Pb activity in the surface samples.(3)An horizon at between 2 and 3 m depth containing 210Pb activity above natural levels. This horizon is also associated with 137Cs and a maximum in total ß activity.The ice samples have been dated on the basis of a simplified two–component model, the “fresh“contribution determined by 2l0Pb and the old component by 32Si. The following conclusions can be drawn from these observations:(1)The model age of the snout ice is c. 850 years.(2)The average rate of ice movement in the lower glacier is about 2 m/year, which compares well with the annual movement rate of 2.65 m/year observed since 1974.

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Magnetostratigraphic and uranium-series dating of fossiliferous cave sediments in Jinyuan Cave, Liaoning Province, northeast China

Quaternary International ◽

10.1016/j.quaint.2020.11.031 ◽

2020 ◽

Cited By ~ 1

Author(s):

Junyi Ge ◽

Chenglong Deng ◽

Qingfeng Shao ◽

Yuan Wang ◽

Ruiping Tang ◽

...

Keyword(s):

Northeast China ◽

Liaoning Province ◽

Uranium Series ◽

Cave Sediments ◽

Uranium Series Dating

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Oldest cave art found in Sulawesi

Science Advances ◽

10.1126/sciadv.abd4648 ◽

2021 ◽

Vol 7 (3) ◽

pp. eabd4648

Author(s):

Adam Brumm ◽

Adhi Agus Oktaviana ◽

Basran Burhan ◽

Budianto Hakim ◽

Rustan Lebe ◽

...

Keyword(s):

Rock Art ◽

Karst Area ◽

Uranium Series ◽

Island Southeast Asia ◽

South Sulawesi ◽

Figurative Painting ◽

Uranium Series Dating ◽

Cave Paintings ◽

Minimum Age ◽

Cave Art

Indonesia harbors some of the oldest known surviving cave art. Previously, the earliest dated rock art from this region was a figurative painting of a Sulawesi warty pig (Sus celebensis). This image from Leang Bulu’ Sipong 4 in the limestone karsts of Maros-Pangkep, South Sulawesi, was created at least 43,900 years ago (43.9 ka) based on Uranium-series dating. Here, we report the Uranium-series dating of two figurative cave paintings of Sulawesi warty pigs recently discovered in the same karst area. The oldest, with a minimum age of 45.5 ka, is from Leang Tedongnge. The second image, from Leang Balangajia 1, dates to at least 32 ka. To our knowledge, the animal painting from Leang Tedongnge is the earliest known representational work of art in the world. There is no reason to suppose, however, that this early rock art is a unique example in Island Southeast Asia or the wider region.

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