摘要
本文测定了西沙群岛永乐环礁现代鳞碎磲壳的碳、氧、锶同位素组成。碳、锶同位素组成是现以年为周期的规律性变化。碳同位素组成与碎磲的生长发育阶段、生长速率、共生藻类的产率及光照量有关。研究表明，碎磲有三个生长期，即幼年期、发育期和性成熟期。在这三个期，年增长速率为慢-快-慢，相应的碳同位素变化特点为小一大一小。锶同位素的周期性变化与碳同位素的周期性变化基本一致，即呈峰-峰相对和谷-谷相对的正相关关系。锶同位素对附近大陆的降雨量和河流排放量有灵敏的反映。
A living tridacnidae was collected from the Xisa archipelago of China in 1983. By careful drilling with a microbit along the growth-lines of the shell. 55 samples were successfully picked up for C, O isotopic analysis and 44 samples for Sr isotopic analysis. C and Sr isotopic compositlons show regular changes with an annual cycle as seen by Jones (1986), suggesting an age at least of 12 years old. The results of C isotope measurement revealed that tridacnidae has experienced three growing periods: childhood, development and sexually mature periods. The C isotopic composltion is related to the stages of physiologic development. productivity of paragenesis algae and flux of light irradiation. The Sr isotopic composition also shows clearly regular fIuctuations with an annual cycle relative to C isotope. This study demonstrates that Sr isotope is a sensitive tracer of the flux of rainfall in the neighboring continents and the flux of drainage of rivers.
出处
《矿物学报》
CAS
CSCD
北大核心
1999年第2期148-153,共6页
Acta Mineralogica Sinica
基金
成矿机制国家重点实验室研究经费资助
关键词
砗磲壳
稳定同位素
碳
氟
生理变化
古气候
tridacnidae
stable isotope
paleoclimate
metabolism
palaeoclimate
