【作者】 赵淼；

【导师】 程立人；

【作者基本信息】 吉林大学 ， 古生物学与地层学， 2010， 硕士

【摘要】 本文重点研究了辽宁本溪地区晚石炭世早期本溪组的层型剖面——牛毛岭剖面。按其岩性,将研究区该时期分为上下两个岩性段,下部为紫色含铁铝泥岩段,上部为碎屑岩夹灰岩段。其中所夹5层较厚的灰岩均含丰富的古动物化石,如(蜓)类、腕足类、珊瑚类、牙形刺、双壳类等。在众多的动物化石中,除牙形刺外,(蜓)类是最具时代意义的。此外,实测剖面时在上蚂蚁灰岩之上和小峪灰岩之上新发现2层灰岩,另有三层发现了夹泥灰岩透镜体。其中上蚂蚁之上的灰岩含类化石及大量生物碎屑(剖面第33层)。到目前为止含灰岩共计6层,相对前人的研究又增加了1层。类研究方面,系统的采集了化石,共鉴定出(蜓)类13属71种(含比较种)。并对其中的代表属种11属33种进行了描述,虽未发现新种,但是发现了一些在研究区第一次出现的老属种,延长了某些老属种分布时间。这些发现,虽不是新属新种,但扩大了研究区(蜓)类动物群组成分子。如以往认为Millerella,Pseudostaffella仅分布在本溪组个别层位,现在该属存在于本溪组所有含灰岩层中。另外,还就含地层时代、生物地层划分等问题进行了讨论。更多还原

【Abstract】 Stratigraphic section of niumao ridge in benxi in Liaoning province was named by Benxi stratotype in early time of Late Carboniferous in southern Region of north– northeast China, which established by Zhao Yazeng in 1926. the study area is located in Benxi area, eastern of Liaoning Province. Stratigraphic area belongs to north zoning of northeast China of the North China platform area. And this area is of the features of continuously exposing and good outcrops and clear top and bottom boundaries. The effects of later tectonic movement in this area was slight. Animal and plant fossils were rich here, even the evolutionary sequence about fusulinds fossils was more complete and clear. It is the standard area for stratigraphic division and correlation about the early time of Late Carboniferous in northeast of China.The essay took the Section of Niumao ridge as the study object. And we had identified 71 species in 13 genera (include comparative species) and described the representative species of 33 species in 11 genera through the ways of re-measurement for the profile and collecting systemically for fossils and observation for lines about the corresponding layers of surrounding neighbors. And the essay also had discussed the age of fusulinds-in’s layer and divided the layer of organism.The layer of early time of Late Carboniferous in study area was named Benxi group. It’s in touch with Majiagou group in middle Ordovician for parallel unconformity and integrated cove-raged by Taiyuan group on it. The thickness of Benxi group in study area is 158.4m and it can be further divided into 2 lithologics according it’s lithology. The lower is purple mudstone with Fe-Al and the upper is clastic with limestone. In it 5 thicker limestone layers are rich of fossils like fusulinds , brachiopods, corals, conodonts, bivalves, etc. in various of fossils, the fusulinds is the most significant for the Times except the conodonts. On the other side, 2 layers of limestone were found above the ants limestone layer and Xiaoyu limestone layer when profiles was measured. And folder marl lenses were found in other 3 layers. The limestone above the top of ants is rich of fusulinds fossils and a lot of biological debris (Section 33 layers). Till now there were 6 layers which 1 layer more than the study before. with fusulinds fossils in it.At the research of fusulinds aspect, two stages had been divided according to the characteristics of occurrence, development and prosperity in Taizi river valley. The first stage is the time of erliest fusulinds biological composition in Benxi period in Benxi area with the equivalent of Eostaffella Subsolana belt who had not been found in the profile of Niumao ridge. The second stage of the fusulinds species composition is equivalent to Fusulina-Fusulinella belt. This two kinds of fusulinds fossils were the most common on the top of Benxi group in Niumao ridge. And they represented the peak stage of fusulinds fauna in the early time of Late Carboniferous. And after study 5 subzones were further divided as follows: Fusulina–Fusulinella zone:⑤Fusulina cylindrica-F.quasicylindrica subzones;④Fusulinella provecta subzones;③Pseudostaffella sphaeroidea subzones;②Fusulina konnoi subzones;①Fusulina schellwieni subzonesThe division plan could be juxtaposed on corresponding layers with the most areas domestic and foreign. Millerella,Pseudostaffella were only two distributed in individual layer on the top of Benxi group had been changed. And the true is that they are in all of the fusulinds layers on the top of Benxi group, at least this is the case in Niumao ridge.更多还原