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巢湖平顶山北坡剖面下三叠统岩石化学成分分析表明,SiO2、Al2O3、Fe2O3、FeO、MgO、Na2O、K2O、TiO2、P2O5及微量元素Ba、V、Be、Nb、Zn、Cu、Ni、Co、Pb主要富集在下三叠统格里斯巴赫(Griesbachian)、迪纳(Dienerian)及斯密斯(Smithian)亚阶中,形成了8次显著的正异常,异常的强度、规模由下向上呈下降趋势;微量元素Sr和常量元素CaO主要富集在下三叠统上部斯帕斯(Spathian)亚阶中,其含量由下向上呈逐渐增加趋势.前者含量与碳酸盐岩的碳同位素组成(δ13C)呈负相关关系,后者含量与碳酸盐岩的碳同位素组成(δ13C)呈正相关关系.海相碳酸盐岩碳同位素组成(δ13C)指示初始生产力大小,同时亦是海洋生态环境改善的指示标志;负相关表明环境恶化、生物萧条,正相关表明环境适宜、生物繁盛.据常量元素和微量元素分布异常特点在下三叠统地层中识别出8次地质事件,其规模及影响强度由早到晚逐渐变小及减弱;晚二叠世末期及早三叠世初期的火山喷发将各种有害元素大量输向海洋,导致海水中粘土矿物、微量元素含量异常增高,海洋生态环境恶化.随着时间推移,火山活动逐渐平息,海洋中各种有害组分逐渐排除,海水得到净化,生态环境渐渐恢复.
Chemical composition analysis of the Lower Triassic rocks in the northern slope of Pingdingshan in Chaohu shows that SiO2, Al2O3, Fe2O3, FeO, MgO, Na2O, K2O, TiO2, P2O5 and trace elements Ba, V, Be, Nb, Zn, Cu, Ni, Co , Pb is mainly enriched in the Lower Triassic Griesbachian, Dienerian and Smithian sub-series, forming eight significant positive anomalies with anomalous intensity, decreasing in size from bottom to top The trace element Sr and the major element CaO are mainly enriched in the Spathian subfacies of Upper Triassic, and their contents gradually increase from bottom to top.The content of carbon isotope of carbonates (δ13C ), And the latter is positively correlated with carbon isotopic composition (δ13C) of carbonate rocks.The carbon isotopic composition (δ13C) of marine carbonate indicates the initial productivity and also the improvement of marine ecological environment The positive correlation indicates that the environment is suitable and the biology is prosperous.According to the characteristics of the anomalous distribution of the major elements and trace elements, 8 geological events were identified in the Lower Triassic strata, the scale and intensity of which are affected by the early Night gradually diminish and weakened; the Late Permian and Early Triassic volcano eruption a large number of harmful elements transported to the sea, resulting in the seawater of clay minerals, trace elements anomalies increased marine environment deterioration .As time Passing, the volcanic activities gradually subsided, various harmful components in the oceans were gradually eliminated, the sea water was purified, and the ecological environment was gradually restored.