The 226 Ra-210 Pb and 228 Ra-228 Th ages were obtained for barite crystals in hydrothermal sulfide deposits taken at the Okinawa Trough and the Southern Mariana Trough. After calibrating the measurement systems with standard samples with pitchblende, it was confirmed that the U and Th concentrations obtained for GSJ samples are consistent with literature values. It was shown that radon does not escape from barite crystals extracted from hydrothermal sulfide deposits, which indicates that 226 Ra-210 Pb dating method works for these barite crystals. Most of the 226 Ra-210 Pb and 228 Ra-228 Th ages are younger than ESR and U-Th ages, where this inconsistency would be explained by the mixture of the barite crystals with younger and older ages, formed by several hydrothermal events.

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Eolian dust deposits in north China provide an excellent means of determining past variations in continental paleoclimate and atmospheric circulation. However, debate still exists on which deserts in east Asia are the dominant sources of Chinese loess and whether the dust provenance has shifted significantly at different time scales. Here we present new constraints on the provenance of fine‐grained dust deposited on the central Chinese Loess Plateau (CLP) by combining electron spin resonance signal intensity and crystallinity index of fine‐grained quartz contained in samples from two loess‐paleosol sequences. Our results show that the fine‐grained dust deposits on the CLP originate mainly from the Gobi desert in southern Mongolia and the sandy deserts in northern China (primarily the Badain Juran and Tengger deserts), rather than from the Taklimakan desert in western China, at least during the last climatic cycle. The dominant source of fine‐grained dust varied significantly, from southern Mongolia during cold periods, to northern China during warm periods. The glacial‐interglacial provenance fluctuations are strongly coupled with changes in the intensity of the near‐surface northwesterly winter monsoon.

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