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云南湖泊多属中等矿化度的淡水湖泊,碳酸盐沉积物处于缓慢的积累过程。就其外形和成分可分为微粒碳酸盐、颗粒碳酸盐、生物贝壳碳酸盐和陆源碎屑碳酸盐。颗粒碳酸盐多分布在特定环境的湖区,集合粒成因与微生物的生物化学沉积作用有关;球状粒为微晶方解石组成,由藻群落及其代谢物形成的微环境对方解石缓慢沉淀有利;鲕状粒的形成可能与湖泊不定期干涸引起镁、钙比值变化及方解石、文石交替沉淀有关。微粒方解石是碳酸盐沉积的主要矿物形式,局部湖区形成的以颗粒碳酸盐为主的堆积体是云南湖泊早期碳酸盐沉积作用的主要特点。
Most of the lakes in Yunnan are moderately salinity freshwater lakes and carbonate sediments are in a slow accumulation process. Its shape and composition can be divided into particulate carbonate, particulate carbonate, biological shell carbonate and terrigenous clastic carbonate. Particulate carbonates are distributed in the lake area with specific environment. The origin of aggregate grains is related to the biochemical sedimentation of microorganisms. The globular grains are composed of microcrystalline calcite. The microenvironment formed by algae communities and their metabolites is favorable for slow precipitation of calcite. The formation of pellets may be related to the irregular change of magnesium and calcium in the lakes and the alternation of calcite and aragonite. Particulate calcite is the main mineral form of carbonate deposition. Particulate carbonate-dominated sediments formed in the local lakes are the main characteristics of early carbonate sedimentation in Yunnan lakes.