scholarly journals pyUserCalc: A revised Jupyter notebook calculator for uranium‐series disequilibria in basalts

2021 ◽  
Author(s):  
Lynne J. Elkins ◽  
Marc Spiegelman
Keyword(s):  
Uranium Series

Radiometric dating of hillslope calcrete in the Negev Desert, Israel

2008 ◽  
Vol 104 (11/12) ◽  
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.

scholarly journals Oldest cave art found in Sulawesi

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.

scholarly journals Insights into the Galápagos plume from uranium-series isotopes of recently erupted basalts

2011 ◽  
Vol 12 (9) ◽  
pp. n/a-n/a ◽  
Author(s):  
Heather K. Handley ◽  
Simon Turner ◽  
Kim Berlo ◽  
Christoph Beier ◽  
Alberto E. Saal
Keyword(s):  
Uranium Series ◽  
Galapagos Plume

scholarly journals The Frontiers of Uranium-series Research

Eos ◽  
2014 ◽  
Vol 95 (21) ◽  
pp. 178-178
Author(s):  
Heather Handley ◽  
Simon Turner
Keyword(s):  
Uranium Series

scholarly journals Direct dating of Pleistocene stegodon from Timor Island, East Nusa Tenggara

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1788 ◽  
Author(s):  
Julien Louys ◽  
Gilbert J. Price ◽  
Sue O’Connor
Keyword(s):  
Environmental Changes ◽  
Southeast Asian ◽  
Oceanic Islands ◽  
Current Data ◽  
Island Population ◽  
Modern Humans ◽  
Uranium Series ◽  
Uranium Series Dating

Stegodons are a commonly recovered extinct proboscidean (elephants and allies) from the Pleistocene record of Southeast Asian oceanic islands. Estimates on when stegodons arrived on individual islands and the timings of their extinctions are poorly constrained due to few reported direct geochronological analyses of their remains. Here we report on uranium-series dating of a stegodon tusk recovered from the Ainaro Gravels of Timor. The six dates obtained indicate the local presence of stegodons in Timor at or before 130 ka, significantly pre-dating the earliest evidence of humans on the island. On the basis of current data, we find no evidence for significant environmental changes or the presence of modern humans in the region during that time. Thus, we do not consider either of these factors to have contributed significantly to their extinction. In the absence of these, we propose that their extinction was possibly the result of long-term demographic and genetic declines associated with an isolated island population.

scholarly journals Uranium-series comminution ages of continental sediments: Case study of a Pleistocene alluvial fan

2010 ◽  
Vol 296 (3-4) ◽  
pp. 244-254 ◽  
Author(s):  
Victoria E. Lee ◽  
Donald J. DePaolo ◽  
John N. Christensen
Keyword(s):  
Alluvial Fan ◽  
Uranium Series
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