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礁岩,或称生物礁岩,是生物礁在岩石学研究范畴里的统称,它是碳酸盐岩中重要的一类。礁岩的主要格架组分决定于造礁生物的门类,它在各地质历史时期随着生物演化而不同,如晚前寒武纪为叠层石礁(藻礁)、寒武纪—奥陶纪早期多为古杯礁和海绵礁、奥陶纪中期—泥盆纪多为苔藓虫礁、层孔虫礁和(床板)珊瑚礁、石炭纪—二叠纪多为石灰藻礁和(四射)珊瑚礁、三叠纪—白垩纪多为石灰藻礁和(六射)珊瑚礁、第三纪—现代则为(六射)珊瑚礁和石灰藻礁。实际上,生物礁的构成是生物与非生物诸因素,如生物作用、沉积作用、机械破坏作用和胶结作用等建造与改造互相作用的过程。所以,礁岩的构造、结构、组分、成岩作用变化等,比起其它类型碳酸盐岩要复杂得多。对礁岩成岩作用的研究会对生物礁的形成发展获得更细致的认识,对分析认识古代生物礁和礁岩的形成、环境变化、相带划分及岩石学特征等方面也会有所启示。
Reef rocks, or bio-reefs, are reefs collectively referred to in the field of petrology and are an important category of carbonate rocks. The main framework components of reefs are determined by the classes of reef creatures, which vary with the evolution of the organisms during the geological history. For example, the Late Precambrian was a stratiform reef (algae reef), Cambrian-Austria In the early years of the Ordovician, the ancient reefs and sponges were mostly reefs. During the Ordovician period, most of the Devonian were bryozoan reefs, foraminifer reefs and coral reefs, and most of the Carboniferous-Permian limestone reefs and (Reefs), Triassic - Cretaceous mostly limestone reefs and (six shots) coral reefs, the Tertiary - modern (six shots) coral reefs and lime algae reefs. In fact, reef formation is a biological and non-biological factors, such as biological processes, sedimentation, mechanical destruction and cementation, construction and transformation of the interaction process. Therefore, reef rock structure, structure, composition, diagenetic changes, etc., than any other type of carbonate rock is much more complex. The study on the diagenesis of reefs will give a more detailed understanding of the formation and development of reefs and will also provide some enlightenment for the analysis of the formation of ancient reefs and reefs, environmental changes, facies belt division and petrology characteristics.