Calibration of the production rate of cosmogenic 36Cl from Fe

Cosmogenic Exposure Dating (36Cl) of Landforms on Jan Mayen, North Atlantic, and the Effects of Bedrock Formation Age Assumptions on 36Cl Ages

“…All CRONUScalc code, including these modifications, is publicly available on Bitbucket at https://bitbucket.org/cronusearth/cronus-calc/ [accessed on 14 September 2021; v2.2, tag: Anjar_et_al_2021_JanMayen]. The CRONUScalc code was also updated and recalibrated to use the recently published rates for cosmogenic 36 Cl production from iron published in Moore et al (2019) [28]. These new rates are based on modern, robust analyses of multiple high-iron samples and can be incorporated in a similar format to the other spallation production rates already present in the code, unlike the previous Stone et al (2005) rates [29].…”

“…Production Rate (at 36 Final results for exposure ages presented in this paper use the geomagnetically corrected Lal (1991) [33]/Stone (2000) [34] scaling (LM) [5,9] and 36 Cl production rates from Marrero et al (2021) [30] and Moore et al (2019) [28], as described above. A range of rock formation ages ranging from infinite (yielding youngest exposure age) to "equal to exposure age" (yielding oldest possible exposure age) was used to evaluate a range of scenarios.…”

Exposure dating of detrital magnetite using <sup>3</sup>He enabled by microCT and calibration of the cosmogenic <sup>3</sup>He production rate in magnetite

“…We show that microCT scanning of magnetite grains significantly improves the quality and reproducibility of 3 He mea-surements, making the use of magnetite as a target phase for in situ exposure dating more robust and reliable. The utility of magnetite for deriving watershed-averaged erosion rates due to its resistance to erosion has already been demonstrated using 36 Cl (Moore and Granger, 2019b). The mi-croCT screening approach makes it feasible to also use 3 He in magnetite for the same purpose.…”

“…Magnetite is resistant to weathering and can also be used for detrital studies. After a recent calibration of the 36 Cl production rate (Moore and Granger, 2019a), detrital magnetite was successfully used as a target phase for deriving watershed-averaged denudation rates (Moore and Granger, 2019b). Magnetite has also been developed as a target phase for cosmogenic 10 Be dating (Granger et al, 2013b;Rogers et al, 2013;Moore, 2017).…”

Late pleistocene to holocene climate and environmental changes in Greece

“…However, its application on mid to highly serpentinized ophiolitic rocks (i.e. silicate rocks with high concentrations of Mg and Fe and very low to insignificant concentrations of Ca, K and Ti) such as those dominating the glaciated valleys on Mt Mavrovouni, is challenging as the main production of cosmogenic 36 Cl atoms is expected to mainly take place from neutron capture of stable Cl in the rock and Fe spallation (see section 2.2.2), which are processes that are not fully explored and are sources of uncertainty (Gosse and Phillips, 2001;Marrero et al, 2016b;Moore and Granger, 2019). This application is attempted for the first time, and although theoretically this should not cause any major issues, it is an element of innovation.…”