元古代光球疑源类Valeria lophostriata(Jank.)的全球分布(英文)

GLOBAL DISTRIBUTION OF THE PROTEROZOIC SPHAEROMORPH ACRITARCH Valeria lophostriata (JANKAUSKAS)

Valeria lophostriata是一种具明显纹饰有机壁的球状疑源类微体化石 ,对它的近 30个已知化石记录进行了评论。发现其产地集中在北纬 30°以北 ;并在近 7亿年的时间间隔 ,以双峰态时间分布。因此 ,将它作为重要的生物地层标志是不适宜的。其表面特征的韵律式样可能是Belousov- Zhabotinsky反应的一种显微实例。作者提出该属种的纹饰特征和壳壁的化学成分应是今后深入研究的课题。

The nearly three dozen known occurrences of the distinctly ornamented organic walled microfossil Valeria lophostriata are reviewed. The localities are concentrated north of latitude 30°N , and span a time interval of about 700 Ma., exhibiting a bimodal age distribution. The status of the taxon as an important biostratigraphic marker is questioned. The diagnostic rhythmic surface pattern may be a microscopic example of the Belousov Zhabotinsky reaction.