华北板块东南缘淮南地区在淮南、霍邱、凤阳等地在晚前寒武纪形成一套完整的海相碎屑岩和碳酸盐岩沉积盖层。八公山群寿县组主要为一套浅灰色含钙质石英细砂–粉砂岩。为探讨寿县组地层沉积物源从而采集寿县组出露区未风化新鲜岩石样品...华北板块东南缘淮南地区在淮南、霍邱、凤阳等地在晚前寒武纪形成一套完整的海相碎屑岩和碳酸盐岩沉积盖层。八公山群寿县组主要为一套浅灰色含钙质石英细砂–粉砂岩。为探讨寿县组地层沉积物源从而采集寿县组出露区未风化新鲜岩石样品,本文对其进行岩石学特征分析并制成显微薄片在正交偏光显微镜下对其进行粒度分析,结合萨胡(Sahu)判别函数结果和概率累计曲线图特征,认为寿县组碎屑岩分选好,磨圆一般,沉积环境为浅海–临滨带的陆棚沉积环境。在收集前人碎屑锆石年龄并结合淮南周边地区基性侵入岩的定年结果后,将八公山群寿县组沉积时限限定在1.0~0.95 Ga之间。基于非参数性检验的定量分析法(K-S检验)验证不同地区的物源区差异性,并生成年龄累计曲线图,对比华北克拉通中–新元古代时期裂谷岩浆活动及其东部各区域出现的碎屑锆石年龄,判断淮南地区寿县组沉积物源可能为劳伦古大陆造山带,是否来自华北克拉通内部仍然需要进一步研究。A complete set of Marine clastic rock and carbonate sedimentary cover was formed in Huainan, Huoqiu and Fengyang in the southeast of North China Craton during the late Precambrian period. The Shouxian Formation of Bagongshan Group is mainly a set of light gray calcareous quartz fine sand-siltstone. In order to explore the source of sediments in the Shouxian Formation and collect samples of unweathered fresh rocks from the outcrop area of the Shouxian Formation, this paper analyzes their petrology characteristics and makes microslices, analyzes their particle size under the orthogonal polarization microscope, and combines the results of Sahu discriminant function and the characteristics of probability accumulation curve, which suggests that the clastic rocks of the Shouxian Formation are well sorted and generally rounded. The sedimentary environment is shelf sedimentary environment in shallow sea-coastal zone. Based on the dating of former detrital zircons and the dating of basic intrusive rocks in Huainan area, the deposition time of Shouxian Formation in Bagongshan Group is limited to 1.0~0.95 Ga. The quantitative analysis based on non-parametric test (K-S test) verifies the provenance differences in different regions, and generates a cumulative age curve. By comparing the Mesoproterozoic rifting magmatic activity in the North China Craton and the ages of detrital zircons in various eastern regions, it is concluded that the sediment source of Shouxian Formation in Huainan area may be Laurentian orogenic belt. Whether it comes from within the North China Craton still needs further study.展开更多
文摘华北板块东南缘淮南地区在淮南、霍邱、凤阳等地在晚前寒武纪形成一套完整的海相碎屑岩和碳酸盐岩沉积盖层。八公山群寿县组主要为一套浅灰色含钙质石英细砂–粉砂岩。为探讨寿县组地层沉积物源从而采集寿县组出露区未风化新鲜岩石样品,本文对其进行岩石学特征分析并制成显微薄片在正交偏光显微镜下对其进行粒度分析,结合萨胡(Sahu)判别函数结果和概率累计曲线图特征,认为寿县组碎屑岩分选好,磨圆一般,沉积环境为浅海–临滨带的陆棚沉积环境。在收集前人碎屑锆石年龄并结合淮南周边地区基性侵入岩的定年结果后,将八公山群寿县组沉积时限限定在1.0~0.95 Ga之间。基于非参数性检验的定量分析法(K-S检验)验证不同地区的物源区差异性,并生成年龄累计曲线图,对比华北克拉通中–新元古代时期裂谷岩浆活动及其东部各区域出现的碎屑锆石年龄,判断淮南地区寿县组沉积物源可能为劳伦古大陆造山带,是否来自华北克拉通内部仍然需要进一步研究。A complete set of Marine clastic rock and carbonate sedimentary cover was formed in Huainan, Huoqiu and Fengyang in the southeast of North China Craton during the late Precambrian period. The Shouxian Formation of Bagongshan Group is mainly a set of light gray calcareous quartz fine sand-siltstone. In order to explore the source of sediments in the Shouxian Formation and collect samples of unweathered fresh rocks from the outcrop area of the Shouxian Formation, this paper analyzes their petrology characteristics and makes microslices, analyzes their particle size under the orthogonal polarization microscope, and combines the results of Sahu discriminant function and the characteristics of probability accumulation curve, which suggests that the clastic rocks of the Shouxian Formation are well sorted and generally rounded. The sedimentary environment is shelf sedimentary environment in shallow sea-coastal zone. Based on the dating of former detrital zircons and the dating of basic intrusive rocks in Huainan area, the deposition time of Shouxian Formation in Bagongshan Group is limited to 1.0~0.95 Ga. The quantitative analysis based on non-parametric test (K-S test) verifies the provenance differences in different regions, and generates a cumulative age curve. By comparing the Mesoproterozoic rifting magmatic activity in the North China Craton and the ages of detrital zircons in various eastern regions, it is concluded that the sediment source of Shouxian Formation in Huainan area may be Laurentian orogenic belt. Whether it comes from within the North China Craton still needs further study.
