Be-10 in Australasian microtektites compared to tektites: Size and geographic controls

• Published in: Geology
• Main Authors: Rochette, Philippe, Braucher, R., Folco, L., Horng, C. S., Aumaître, G., Bourlès, Didier, Keddadouche, K.
• Other Authors: Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA), University of Pisa - Università di Pisa, Academia Sinica
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: badain jaran desert; geomagnetic reversal; constraints; [SDV]Life Sciences [q-bio]; [SDE]Environmental Sciences; Jaran; Antarc*; Antarctica
• Online Access: https://hal.inrae.fr/hal-02621322; https://doi.org/10.1130/G46156Y.1

International audience In his welcome commentary on our paper (Rochette et al. 2018), Mizera (2019) challenges our preferred interpretation for the Australasian tektite (AAT) source: soil-covered old continental sediments, i.e., 10Be-rich onto 10Be-poor material. Blum et al.’s (1992) analysis of Sr and Nd isotopic ratios points toward Jurassic-Cretaceous sediments, such as those found in abundance in south Laos and east Thailand (Singsoupho et al., 2014). Our point was that Chinese loess, or any other thick Quaternary sedimentary column, cannot account for the consistent 10Be gradient observed from Indochina to Antarctica, interpreted as the translation of a vertical gradient in the target. Mizera put forward instead his previously published (Mizera et al., 2016) target hypothesis in northern China deserts (i.e., the source of Chinese loess dust), and specifically in the Baidan Jaran desert (BJD), using a stack of glacial period sediments (10Be-poor) and interglacial paleosol (10Be-rich).