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在5亿多年前,重庆地区还是一片汪洋大海,幽蓝的浅海里只有蓝藻等低等微生物。慢慢地,叠层石开始形成,海洋动物也逐渐出现并繁荣起来。后来,叠层石退出了历史舞台,但它们的遗骸保存下来并形成了化石。历次造山运动使重庆一带抬升成为陆地,美丽的叠层石也随之初现。叠层石是一种改变了地球演化进程的化石,正是它,让大气含氧量急剧升高,为后来的生命演化打下了基础。叠层石在前寒武纪十分发育,进入寒武纪后,却随着后生动物(除原生动物外所有其他动物的总称)的崛起而衰落了。
In more than 500 million years ago, the area of Chongqing was still a sea of vast oceans, and only the lower microbes such as cyanobacteria were found in the faint blue sea. Slowly, the stratum began to form and marine animals gradually emerged and thrived. Later, the laminated stone quits the stage of history, but their remains are preserved and fossilized. The previous orogenic activities have led to the uplifting of the area to the land in Chongqing, and the beautiful stratified stone also appeared. Stratum is a kind of fossil that has changed the evolution of the earth. It is so that the oxygen content of the atmosphere rises sharply, laying the foundation for the later evolution of life. Stratosphere, which developed very well during the Precambrian period, entered the Cambrian era but declined with the rise of metazoans (a collective term for all other animals except protozoa).