论文部分内容阅读
湘西北的志留纪海相红层发育、鱼化石丰富,其中湖南澧县山门水库周边地区的志留系以含世界范围内胴甲鱼类乃至盾皮鱼类的最低层位而著称。然而前人在山门水库周边地区未曾系统开展志留系的地层学工作,含Shimenolepis graniferus等盾皮鱼类与中华棘鱼类鳍刺化石的准确层位以及相关志留纪地层的精确划分迄今尚无确切记载与详细讨论。依据2008年以来的3次野外地质考察、剖面测制、鱼类化石发掘与初步研究,对该地区出露的志留纪含鱼地层及层序进行了厘定,相关地层包括含丰富中华棘鱼类鳍刺化石的下红层溶溪组、含丰富盾皮鱼类化石的罗德洛统红层小溪组以及夹于二者之间、在本地区尚未见鱼化石的秀山组。在此基础上,探讨了澧县地区志留纪含鱼地层的时代,并与华南其他地区志留纪含鱼地层进行了对比。研究工作的开展,不仅为深入研究胴甲鱼类乃至盾皮鱼类的形态学、系统学以及探讨有颌类的早期演化等方面提供了一批鱼类化石新材料,而且为华南扬子区志留纪两套海相红层——下红层与罗德洛统红层的划分对比及其时代归属提供了可靠的古鱼类学证据。
The Silurian marine red beds in northwestern Hunan are rich in red fossils and fish fossils. Among them, the Silurian in the surrounding areas of the Shanmen reservoir in Lixian County, Hunan Province, is known for containing the lowest layer of carp shellfish and even walrus in the world. However, the predecessors did not systematically carry out the stratigraphic work of the Silurian in the surrounding areas of the Shanmen Reservoir. The exact stratigraphic division of the shield fossils such as the Shimenolepis graniferus and the Chinese spinous fish and the related Silurian strata have so far been in existence No exact record and detailed discussion. Based on the three field geological surveys, profile surveys, fish fossil excavations and preliminary studies since 2008, the Silurian fish-bearing strata and sequences exposed in the area are determined. The related strata include the rich tropical echinops The fossil-like fossils of the Lower Triassic, the Lower Triassic Fossil, the Rhododendron creek, which is rich in shield fossil fossils, and the Xiushan Formation, which is sandwiched between the fossil fossils. On this basis, the age of the Silurian fish-bearing strata in Pixian area was discussed and compared with the Silurian fish-bearing strata in other areas of South China. The research work has not only provided a new batch of fish fossil materials for the further study of morphological and systematics of carp and even crustacean fish, Two sets of maritime red beds in Jiujiu - providing reliable evidence of paleontology from the contrast and dating of the red beds to the Rhodolite.