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在湖北崇阳二叠系-三叠系界线附近地层中共获得400余个介形虫实体标本,归属4科10属30种.其中在二叠纪末生物大灭绝界线之下长兴组灰岩中发现6属20种,大灭绝界线之上微生物岩中发现7属11种.崇阳微生物岩中的介形虫化石与前人在广西和重庆地区微生物岩中发现的介形虫不但在属种类型上存在差别,而且可作为海水含氧量指标的滤食性分子所占的比例也明显不同,反映出华南地区二叠纪末生物大灭绝后古海洋环境的多样性.在纵向地层序列上,崇阳剖面介形虫化石的分布具有明显的阶段性.在大灭绝界线之下200cm处部分介形虫已开始消失,界线附近再次遭受灭绝,在灭绝界线之上微生物岩的顶部部分属种再度消失.崇阳剖面介形虫的这种分阶段、多幕式演化规律表明,在二叠纪-三叠纪之交这一全球重大地质转折期,作为大灭绝后仅存的几类多细胞生物的介形虫所遭受的损失是个逐渐变化的过程.碳同位素测试分析也显示,古海洋环境的变化早在大灭绝界线之下200cm处就已开始.碳同位素曲线的波动与介形虫属种类型的变化和消失相关,但与介形虫化石的丰度变化没有必然联系.
In the area around the Permian-Triassic boundary in Chongyang, Hubei Province, over 400 specimens of ostracods were obtained, belonging to 4 families, 10 genera and 30 species, of which, Changxing Formation limestone in the boundary of Permian epoch Found in 6 genera and 20 species found in 7 genera and 11 genera above the mass extinction line.The ostracod fossils in Chongyang microbial rock and the ancylostomia found in the microbial rock of the predecessors in Guangxi and Chongqing not only belong to the genera Type, and the proportion of filter-feeding molecules that can be used as an indicator of seawater oxygen content is also significantly different, reflecting the diversity of paleoenvironment after Permian end extinction in southern China.In the longitudinal stratigraphic sequence, In the Chongyang section, the distribution of the ichthyosis fossils has a distinct stage: part of the ichthyosis at 200cm below the mass extinction boundary has begun to disappear, and near the boundary line has again been extinct, and the top part of the microbial rock above the extinction limit Disappear.The staged and multi-curtain evolution of ostracods in Chongyang section shows that during the period of the Permafrost-Triassic transition, a period of major global geological transition, as the only remaining multicellular species after the mass extinction Creatures of ostracods The loss suffered is a process of gradual change.Carbon isotope analysis also shows that the paleoenvironmental changes began as early as 200 cm below the mass extinction boundary.The fluctuation of carbon isotope curves and the change and disappearance of ostracod species But not necessarily related to changes in the abundance of ichthyosis fossils.