Dataset Information

Middle Holocene daily light cycle reconstructed from the strontium/calcium ratios of a fossil giant clam shell.

ABSTRACT: Insolation is an important component of meteorological data because solar energy is the primary and direct driver of weather and climate. Previous analyses of cultivated giant clam shells revealed diurnal variation in the Sr/Ca ratio, which might reflect the influence of the daily light cycle. We applied proxy method to sample from prehistoric era, a fossil giant clam shell collected at Ishigaki Island in southern Japan. The specimen was alive during the middle Holocene and thus exposed to the warmest climate after the last glacial period. This bivalve species is known to form a growth line each day, as confirmed by the analysis of the Sr enrichment bands using EPMA and facilitated age-model. We analyzed the Sr/Ca, Mg/Ca and Ba/Ca ratios along the growth axis, measuring a 2-?m spot size at 2-?m interval using NanoSIMS. The Sr/Ca ratios in the winter layers are characterized by a striking diurnal cycle consisting of narrow growth lines with high Sr/Ca ratios and broad growth bands with low Sr/Ca ratios. These variations, which are consistent with those of the cultivated clam shell, indicate the potential for the reconstruction of the variation in solar insolation during the middle Holocene at a multi-hourly resolution.

SUBMITTER: Hori M

PROVIDER: S-EPMC4348650 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Middle Holocene daily light cycle reconstructed from the strontium/calcium ratios of a fossil giant clam shell.

Hori Masako M Sano Yuji Y Ishida Akizumi A Takahata Naoto N Shirai Kotaro K Watanabe Tsuyoshi T

Scientific reports 20150304

Insolation is an important component of meteorological data because solar energy is the primary and direct driver of weather and climate. Previous analyses of cultivated giant clam shells revealed diurnal variation in the Sr/Ca ratio, which might reflect the influence of the daily light cycle. We applied proxy method to sample from prehistoric era, a fossil giant clam shell collected at Ishigaki Island in southern Japan. The specimen was alive during the middle Holocene and thus exposed to the w ...[more]

PMID: 25736488

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Dataset Information

Middle Holocene daily light cycle reconstructed from the strontium/calcium ratios of a fossil giant clam shell.

Publications

Middle Holocene daily light cycle reconstructed from the strontium/calcium ratios of a fossil giant clam shell.

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