摘要
一、前言分子化石又称化学化石或生物标志化合物,它是表示地质体中检测到的、与天然生物体中某些已知化合物的结构有着广泛成因联系的一类有机化合物。如果说传统的古生物化石是反映古生物体骨骼结构及其形态特征的话,那么分子化石则是表示这些生物体内部某些标志性物质的化学结构类型,并在一定程度上代表了古生物群演化的最特征的“指纹”,可以从总体上反映古生物群的性质及其有机体内部的化学组成和结构特征,蕴含着丰富的地层学信息。因此,分子化石同样具有重要的地层学意义和广阔的地层应用前景。
This paper makes an investigation into the constitution and distribution of molecular fossils from the beds near the Carboniferous-Permian boundary in Fujian, using the method of organic geochemistry, with discussion on the significance of these molecular fossils according to the basic principle of molecular stratigraphy. Four kinds of molecular fossils have been found in these beds, namely normal hydrocarbons, isoprenoid hydrocarbons, steranes and terpanes. In constitution and distribution, these molecular fossils in Zhongjian differ greatly from those in Mapingian or in Gaodian. In Zhongjian, for example, the constituent of n-hydrocarbons comprises mainly the n-hydrocarbons with a smaller carbon-number (C_(15)—C_(18)), but in Mapingian or in Gaodian, with a greater carbon-number (C_(23)—C_(33)). In Zhongjian, the main peak of n-hydrocarbons lies at n-heptadecane (nC_(17)) but in Mapingian or in Gaodian, it lies at n-noneicosane (n-C_(29)). Furthermore, in Mapingian and Gaodian, the common molecular fossils in Zhongjian have disappeared, such.as C_(15)-and C_(16)-tonicane, C_(19-) and C_(20)-dehydrogenational tricyclic terpanes, with the rise of some novel molecular fossils, such as pristane, phytane, C_(21)-and C_(22)-pregnane, C_(20)-tricyclic diterpane and C_(21)—C_(26)-extended tricyclic diterpanes, indicating that the mutation in the evolution and appearance of the biological kingdom in this area have taken place in the strata from Zhongjian to Mapingian. Hence the writer suggests that the Carboniferous-Permian boundary in Fujian should be placed at the base of Mapingian; such an opinion is also supported by coral study (Luo Jin-ding, 1989, in press)
出处
《古生物学报》
CAS
CSCD
北大核心
1990年第6期745-754,共10页
Acta Palaeontologica Sinica
基金
国家自然科学基金
