摘要
当前人们普遍认为地球生物史上最早的后生动物是伊迪卡拉动物群，由软躯印痕化石组成，多数学者认为是刺胞动物，年代约６～７亿年前，而多门类骨骼化石的出现则是寒武系底界的标志。震旦晚期虽有少量报道，但其层位不低于陡山陀组。但是，陈耳化石因其年代古老（１２亿年）而又显示多样的贝壳或骨路的性质，学术界反映谨慎，认为将其归为可疑化石（ｄｕｂｉｏｆｏｓｓｉｌｓ）较为可靠。笔者从化石的保存特征、形态组合面貌、有机与无机成分分析和结构构造研究等多方面对洛南生物群作了较为系统的分析探讨，基本排除其为无机成因构造的可能。由于与已知化石类型无法比较，目前暂将其归入分类位置未定的疑难化石（ｐｒｏｂｌｅｍａｔｉｃ）。
It's a common knowledge that the earliest Metazoan fossils are those of the 600- 700Ma-year-old Edicaran Fauna, represented by soft body fossils, mainly of Cnldaria, and appearance of mulitiply skeleton fossils are still the index of Cambrlan, though micro-skeletonfossils scarcely occurred in the Late Sinian. Therefore, the discovery of possible shell-likefossils in the 1200 Ma-old Xunjiansi Formation of Jixian System arouses a wide suspicion. Acareful study of fossil preservation, attribution of fossil forms, organic and inorganic composition of the fossil wall as well as their texture and structure can basically rule out the possibility of inorganic origin of the specimens, and ascribe them to problematic fossils with nodefinite affinity and their incomparison to the fossil types known.
出处
《西北地质科学》
1997年第1期70-75,T001,共7页
Northwest Geoscience
基金
国家自然科学基金
省教委基金
