鄂西建始罗家坝剖面孤峰组鱼类微体化石的发现  

DISCOVERY OF FISH MICROREMAINS IN THE GUFENG FORMATION AT THE LUOJIABA SECTION FROM JIANSHI, WEST HUBEI

作　　者：毛羽[1] 马强分[1] 冯庆来[1] 

机构地区：[1]中国地质大学生物地质与环境地质国家重点实验室,武汉430074

出　　处：《微体古生物学报》2013年第2期175-183,共9页Acta Micropalaeontologica Sinica

基　　金：国家自然科学基金项目(40839903和40921062)资助

摘　　要：笔者在对湖北恩施建始地区孤峰组进行放射虫和牙形刺的处理研究过程中发现了丰富的鱼类微体化石。对其中部分化石进行了初步的鉴定,软骨鱼纲和硬骨鱼纲鱼类微体化石同时被发现。通过与其它产地同时期的鱼类微体化石相比较,其特征明显:层位集中、分异度高、丰度大、个体整体偏小。由于该研究区地处古赤道地区东特提斯海,气候温暖,上升流发育,海水缺氧,因此发育了一套黑色深水沉积的岩系——孤峰组。而已被报道的其它二叠纪鱼类微体化石的产地并不是此类独特的海洋环境。同时,在其它华南地区孤峰组岩层中也未见该类化石的报道。因此,结合环境对现代鱼类生命活动的影响规律,对当时的鱼类生物与环境展开讨论,间接反映了中二叠世扬子板块建始地区的古地理古气候和古环境。Abundant microremains of fish were found during processing the samples for radiolarian and conodonts from the Jianshi area in Enshi, Hubei. Some fossils, which were identified preliminarily, belong to Chondriehthyes and Osteichthyes. Comparing to the other coeval microremains, the fish mieroremains in this study has the following distinct characteristics： high diversity and richness together with smaller individual size. In the Middle Permian, this area was located in the equatorial region of the eastern Tethys, which was characterized by warm humid climate condi- tion, development of upwelling and anoxic seawater. A series of deep-water black deposits, namely the Gufeng For- mation, was developed. Other Permian fish microremains reported previously were not come from such unique marine environment. Meanwhile, similar fossil was not found in the Gufeng Formation from other places in South China. In this study, the relationship between fish biology and palaeoenvironment conditions were discussed in terms of the in- fluence of environment conditions on the living fish biology, which may reflects the paleogeography, paleoclimate and paleoenvironment of the Middle Permian in the Jianshi area.

关 键 词：鱼类微体化石 鱼鳞 鱼牙 上升流 缺氧环境 孤峰组 中二叠统 鄂西 

分 类 号：Q913[天文地球—古生物学与地层学]