河南理工大学学报（自然科学版）2024，Vol.43Issue(1)：51-60,10.DOI:10.16186/j.cnki.1673-9787.2023030038
海相沉积岩中钙质结核成因综述
Origin of calcareous concretions in marine sedimentary rocks
摘要
Abstract
Objective As a common sedimentary structure in deep-time marine strata,calcareous concre-tions,which is mainly composed of authigenic carbonate mineral aggregates,have become an important ar-chive for studying sedimentary environment,paleoclimate,and sedimentary pore fluid evolution due to their special growth conditions.In order to deeply understand the genesis of different calcareous concretions and highlight their geological significance,Methods this paper reviews the macroscopic morphology,micro-fabrics,and isotopic characteristics of different calcareous concentrations,and elaborates the timing and mode of concretionary growth,and the related biogeochemical processes during their formation.Results Cal-careous concentrations can be formed in the quasi-syndepositional stage,early or late diagenetic stage,with concentric or pervasive growth mode.Its formation mechanism mainly have three ways:(1)In anaerobic envi-ronment,organic matters in the sediment are oxidized by providing electron donors for sulfate-reducing bac-teria,which undergo oxidation and generate bicarbonate ions,leading to an increase in alkalinity in pore wa-ter and the formation of calcareous concentrations;(2)Methane in cold-seep fluids upward to the seafloor is oxidized via consortia of methanotrophic archaea and sulfate-reducing bacteria,increasing carbonate alkalin-ity in sediment porewaters,and promoting in-situ carbonate precipitation;and(3)In deep burial settings,over-pressured porewaters in the sediment trigger the formation of late digenetic carbonates in fractures,which are characterized by the development of"beef"and"cone in cone"structures.Conclusion In recent years,microbial processes involved in the formation of calcareous concentrations have been extensively stud-ied,but more high resolution in-situ analysis is needed to clarify how different biogeochemical processes(e.g.,organic mineralization,sulfate reduction and methane anaerobic oxidation coupling)control on calcare-ous concretion growth,and to further indicate its genetic mechanism.关键词
钙质结核/同位素特征/甲烷厌氧氧化/地球生物化学过程/成岩作用Key words
calcareous concretion/isotopic characteristic/anaerobic oxidation of methane/biogeochemical process/diagenesis分类
天文与地球科学引用本文复制引用
刘超,梁天,刘萧萧,安海花,陈浩,李昕..海相沉积岩中钙质结核成因综述[J].河南理工大学学报（自然科学版）,2024,43(1):51-60,10.基金项目
国家自然科学基金资助项目(42172120,41902102) （42172120,41902102）
