安徽巢湖下三叠统含巢湖龙动物群地层碳氧同位素特征及意义
发布时间：2018-10-24 22:30
【摘要】：安徽巢湖地区在早三叠世斯帕斯亚期经历了从深水盆地到外缓坡两种环境的海退过程。利用稳定碳氧同位素测试结果,对巢湖马家山剖面下三叠统南陵湖组中上段含巢湖龙动物群地层的碳氧同位素特征进行了初步分析,探讨了巢湖龙动物群化石产出层段地层所反映的沉积环境背景。马家山剖面南陵湖组中段及上段δ13C值变化范围在-7.312‰~3.936‰之间,变化幅度为11.248‰,平均值-0.857‰。碳同位素与生物初级生产力成正比,南陵湖组中上段稳定碳同位素曲线大幅度负漂移,说明早三叠世海洋生物量稀少,生物初级生产力较低。同时,研究区δ18 O值变化范围在-12.081‰~-3.545‰之间,变化幅度为-8.536‰,平均值-6.598‰。氧同位素与古海水温度成反比,δ18 O值普遍偏低,很可能说明斯帕斯亚期延续了斯密斯亚期末期海水的高温度。综合巢湖地区马家山剖面南陵湖组中段及上段地层沉积特征及稳定碳氧同位素曲线特征,分析出巢湖龙动物群生活在安静的外缓坡—深水盆地,生物初级生产力较低且海水温度总体偏高的环境中。
[Abstract]:The Chaohu area in Anhui Province experienced a regressive process from deep water basin to gentle slope in the early Triassic Spacia period. Based on the stable carbon and oxygen isotopic test results, the carbon and oxygen isotopic characteristics of Chaohu dragon fauna in the middle and upper member of the lower Triassic Nanling Lake formation in the Majiashan section of Chaohu Lake are preliminarily analyzed. The sedimentary environment background reflected by the strata of the fossil producing strata of the Chaohu Dragon fauna is discussed in this paper. The 未 13C values of the middle and upper sections of Nanling Lake formation in the Majiashan profile range from -7.312 鈥，
本文编号：2292752
[Abstract]:The Chaohu area in Anhui Province experienced a regressive process from deep water basin to gentle slope in the early Triassic Spacia period. Based on the stable carbon and oxygen isotopic test results, the carbon and oxygen isotopic characteristics of Chaohu dragon fauna in the middle and upper member of the lower Triassic Nanling Lake formation in the Majiashan section of Chaohu Lake are preliminarily analyzed. The sedimentary environment background reflected by the strata of the fossil producing strata of the Chaohu Dragon fauna is discussed in this paper. The 未 13C values of the middle and upper sections of Nanling Lake formation in the Majiashan profile range from -7.312 鈥，
本文编号：2292752
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