放射状觅食兼停息(或居住)遗迹化石初步研究

A Preliminary Study of Trace Fossils Formed in Radioactive Food-seeking and Stopping (or Residing)

本文介绍了8个放射状觅食兼停息(或居住)遗迹化石属的特征,讨论了这类遗迹化石的形成方式、形成环境、与古水流方向的关系及测量分析方法。 通过分析,得出几点初步认识:①这类遗迹是生物停息(或居住)一处,靠身体胀缩或其它方式多次往复运动觅食形成;②这类遗迹多形成于安静、沉积速度缓慢的环境;③这类遗迹化石由停息迹(或居住迹)和觅食迹两部分组成,觅食迹(即放射这部分)迎水流方向上多较发育,因而大量统计觅食迹发育的方向可以判断古水流方向。

Trace fossils formed in radioactice food -seeking and stopping (or residing) are those living near the surface of sediments using body expansions and contration or other moving manners to seek food time and again in the neighborhood. They were made up of stopping traces (or residing traces) and food-seeking traces, with their features shown by many radioactive traces ranged ra-dioactively around from a small scope (little blank place, nodule, pit. hidden cave, etc. ). Theory and practice materials show that if such trace fossils were formed in a large number, this means the water energy of their forming environment was not strong and the sedimentary velocity was slow. The food-seeking traces of such trace fossils were more developed against the water-running direction than in any other direction because against the water - running directon food was more easily obtained. According to this feature, counting up me directions in which the radioactive traces of such trace fossils were developed can help to determi e palaeofluvial directions.