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绪言前显生宙化石可以分为三个大类:1)迭层石,2)大型藻类化石,3)微化石。迭层石是地球上已知最古老的生命遗迹之一,并在35亿年前的地层中已有发现。迭层石生存于整个前显生宙后期,经过显生宙直到现在。由于和现代迭层石构造相似,迭层石化石一般被认为是由兰细菌的沉积掩埋,固结和沉淀活动所产生的生物沉积构造。但是,其他细菌也能参与形成现代的迭层石和营造最初的迭层石。迭层石主要赋存在石灰岩和白云岩中,但是前显生宙的迭层石也在燧石,磷灰岩和含铁建造中发现。
INTRODUCTION Pre-Proterozoic fossils can be divided into three broad categories: 1) laminated stone, 2) large algae fossils, and 3) microfossils. Stacked stones are one of the oldest known remains of life on Earth, and were found in strata 3.5 billion years ago. The laminated rock survived the entire late Phanerozoic and passed through the Phanerozoic up to now. Because of the similar structure to modern laminated rocks, laminated fossils are generally considered to be bio-deposited structures that result from the burial, consolidation, and sedimentation of Cymbidium bacteria. However, other bacteria can also participate in the formation of modern laminated stone and the creation of the original laminated stone. Lamellar rocks are mainly found in limestone and dolomite, but the sediments of the Preobservations are also found in chert, apatite and iron-bearing constructions.