Terrestrial ages of seven meteorite strewn fields and two single unpaired meteorites from the Sultanate of Oman determined using ¹⁴C and ¹⁰Be

Abstract

Through the investigation of terrestrial ages of meteorites from Oman, we aim to better understand the time scales of meteorite accumulation and erosion in Oman and the meteorite flux in the past. Here, we present 14C and 14C‐10Be terrestrial ages of seven ordinary chondrite strewn fields and two unpaired single meteorites from the Sultanate of Oman. After critical evaluation of multiple data for each strewn field, we propose “best estimate terrestrial ages,” typically based on 14C/10Be. For objects for which complex irradiation histories are known or suspected, terrestrial ages were calculated solely using 14C. The best estimate strewn field ages range from 8.1 ± 3.0 ka (SaU 001) to 35.2 ± 5.1 ka (Dho 005). Including two previously dated strewn fields, the mean and median age of nine Oman strewn fields is 15.9 ± 12.3 and 13.6 ka, respectively. The new data show a general good agreement with data previously obtained in a different laboratory, and we observe a similar general correlation between strewn field ages and mean weathering grade as in previous work based on individual meteorites. Weathering degree W4 is reached for dated samples after 20–35 ka. While the age statistics of strewn fields does not show the previously observed lack of young events, the low abundance of young (0–5 ka) individual meteorites as compared with older (~20 ka) meteorites is confirmed by our data and remains unexplained.

Once in a summer: Fall history of the JaH 073 strewn field, Sultanate of Oman

“…As the JaH 073 fall happened some 18.1 ka ago (Sliz et al., 2022), there is no direct information about the wind situation during fall time. The overall climatic situation at the end of the last ice age, however, was already similar to the present one, except some displacement of the Intertropical Convergence Zone (ITCZ) due to the more extended ice coverage of the northern hemisphere (Fleitmann & Matter, 2009; Preusser et al., 2002).…”

“…JaH 073 samples gave a 14 C fall age of 18.1 ± 2.7 ka (Sliz et al., 2022). The meteorite seems not to be saturated in 10 Be, which resulted in the underestimated age of 14.4 ka reported earlier by Gnos et al.…”

14C and 14C‐10Be terrestrial age dating system for meteorites—New data for four recently fallen meteorites

“…Sample preparation, CO 2 extraction, and 14 C measurements followed the procedures recently established in our laboratory by Mészáros et al (2018) and Sliz et al (2019Sliz et al ( , 2022. Briefly, samples were milled and the 125-200 μm grain size fraction was selected.…”

“…For example, the conditions supporting or limiting meteorite preservations differ significantly among the different deserts. While meteorites found in the deserts of the Sultanate of Oman, North Africa, the United States, and Australia have average terrestrial ages in the range 30-50 ka (e.g., Al-Kathiri et al, 2005;Jull, 1993Jull, , 2006Jull, , 2010Sliz et al, 2022), meteorites found in the Atacama Desert or in Antarctica can have terrestrial ages up to millions of years (e.g., Cassidy, 2003;Drouard et al, 2019;Gattacceca et al, 2011). Terrestrial ages are crucial data for comprehending and quantifying the processes involved in weathering.…”

“…Carbon-14 and 14 C-10 Be terrestrial age dating has also been applied to mesosiderites (Jull et al, 2009) and iron meteorites (Schnitzer et al, 2012). However, despite the immense potential of this dating system and the importance of the data, there are currently only three laboratories worldwide performing such studies-the University of Arizona, United States (e.g., Jull et al, 2013); the Nagoya University, Japan (Minami et al, 2006); and our group at the University of Bern (Mészáros et al, 2018;Sliz et al, 2019Sliz et al, , 2022.…”