下扬子区下三叠统遗迹化石及其环境意义

Lower Triassic trace fossils from the Lower Yangzi region and their significance of sedimentary environments

遗迹化石是地质时期各类生物在生活期间进行居住、运动、寻食、代谢和生殖等行为习性活动,在沉积物表面或其内部留下的各种痕迹。作为重要的生物标志,遗迹化石可用来判别和恢复古代沉积环境。近年来,笔者在下扬子区的宿松、贵池、泾县、宁国、宜兴等地(图1)的下三叠统,发现大量遗迹化石。本文从遗迹化石组合特征出发,讨论遗迹化石与沉积环境之间的关系。承杨式溥教授鉴定遗迹化石标本,在此深表谢忱。

There are plenty of trace fossils contained in the Lower Triassic rocks of the lower Yang-zi region.They belong to 'Zoophycus, Ouziana aand Skolithos'.These trace fossils can be used for deter ming the sedimentary environments.On the basis of the combination of trace fossils, the paper discusses the palaeohydrodynamic energy, the palaeodepth, the palaeosalinity, the nature of basal deposits and the deposit velocity or deposit rate.