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Snow and rain samples collected in Sendai, Japan, were analyzed for sodium, potassium, magnesium, calcium, and strontium. The chemical composition of the samples can be fairly explained by adding some calcium to diluted seawater. A low Sr/Ca ratio in most of the samples showed that the excess calcium over seawater contribution may be derived from calcite contained in soil dust transported by wind from North China.
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Masami Ichikuni (1978) studied this question.
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