碳酸盐沉积物的成岩作用  

Diagenesis of carbonate sediments

作　　者：赵彦彦[1] 郑永飞[1] 

机构地区：[1]中国科学院壳幔物质与环境重点实验室中国科学技术大学地球和空间科学学院,合肥230026

出　　处：《岩石学报》2011年第2期501-519,共19页Acta Petrologica Sinica

基　　金：中国科学院知识创新工程项目(KZCX2-YW-008);国家自然科学基金项目(40921002)联合资助

摘　　要：化学沉淀碳酸盐矿物在沉积后很容易受到各种作用的影响,其中最重要的是其在成岩阶段所经历的成岩作用。碳酸盐沉积物在成岩过程中主要受大气降水、海水和埋藏过程中孔隙流体的控制,经历一系列压实、溶解、矿物的多相转变、重结晶、胶结等成岩作用,逐渐转变为固结的岩石。在成岩过程中,由于孔隙流体与沉积流体之间的异同以及温度的变化,碳酸盐沉积物的原始矿物成分、地球化学特征可能会很好的保存下来,但在许多情况下,也可能会改变,从而使我们无法准确反演碳酸盐沉积物在沉积时水体的特征。因此,我们在应用碳酸盐岩重建相关古环境和古气候变化的时候,必须要通过有效的方法来对碳酸盐岩是否受到成岩作用的影响进行鉴定。The chemical carbonates are susceptible to post-depositional alteration,especially diagenetic alteration after chemical deposition.Potential diagenetic fluids include seawater,meteoric water and hydrothermal fluid.Sedimentary carbonates are lithified after a series of diagenetic alteration such as compaction,dissolution,precipitation,recrystallization,and cementation.The primary mineral and geochemical signatures can be either preserved or changed during the post-depositional alteration,which are controlled by the composition of diagenetic fluid and the diagenetic temperature.In many cases,however,the post-depositional alteration may impart a secondary signal,so that the chemical signature of sedimentary carbonate no longer accurately reflects its primary property.Thus,a thorough understanding of diagenetic pathways and extents is necessary when interpreting the chemical archives recorded in the carbonate with respect to the construction of paleoenvironment and paleoclimate.

关 键 词：沉积碳酸盐 成岩蚀变 同位素 微量元素 地球化学 

分 类 号：P578.6[天文地球—矿物学]