The current understanding of the origins of modern carbonate muds and their early stages of transformations are reviewed. The fine-grained nature of such sediments makes them susceptible to intensive structural and chemical alteration at relatively shallow burial depths driven especially by mineral instability under microbially mediated reactions within the sediment associated with the decay of organic matter. Whereas the transformation of high Mg calcite (HMC) to low magnesian calcite (LMC) generally takes place incongruently and in situ, that of aragonite is predominantly via congruent dissolution. The loss of aragonite produces a huge potential flux of carbonate which is translocated within the sediment. Parallel to studies on Quaternary sediments, investigations in the stratigraphic record have shown that in low-energy settings the transformation of the aragonite component leads to the formation of diagenetic bedding (such as limestone-marl-alternations or LMAs), and related bipartite lithologies, some types of hardgrounds, secondary carbonate mudrocks, and to the significant modification of the original skeletal biota. There are uncertainties such as the exact sources for the precursor aragonite, where the released carbonates reprecipitate in the shallow sediment column, how much carbonate (and hence carbon) is back-fluxed to the water column, how this affects palaeoenvironmental proxies, and the environmental distributions of these processes. The evidence from the stratigraphic record, from settings where organic matter was able to accumulate promoting these transformations, is that these changes in carbonate-rich sediments took place very early, at shallow (decametre or less) burial depths, affecting what we now see from the micron to the outcrop scale. The complexity and inter-relationships of these fundamental processes has received more attention in recent years, though their implications still seem remarkably undervalued.

回顾了目前对现代碳酸盐岩泥浆起源及其早期转化阶段的认识。这种沉积物的细粒性质使它们容易在相对较浅的埋藏深度发生强烈的结构和化学变化，特别是在沉积物内与有机物腐烂相关的微生物介导的反应下，矿物不稳定。而高镁方解石 (HMC) 向低镁方解石 (LMC) 的转变通常不一致地发生在原位，文石主要通过全等溶解。文石的损失会产生巨大的潜在碳酸盐通量，这些碳酸盐会在沉积物中移位。与第四纪沉积物研究平行，地层记录调查表明，在低能量环境中，文石成分的转化导致成岩层理（如石灰岩-泥灰岩交替或 LMA）的形成，以及相关的二分岩性，某些类型的硬地、次生碳酸盐岩泥岩，以及对原始骨骼生物群的重大改变。存在不确定性，例如前体文石的确切来源，释放的碳酸盐在浅层沉积柱中重新沉淀，有多少碳酸盐（以及碳）回流到水柱中，这如何影响古环境指标，以及这些过程的环境分布。来自地层记录的证据，来自有机质能够积累促进这些转变的环境，是富含碳酸盐的沉积物的这些变化发生在很早的时候，埋藏深度较浅（十米或更小），影响了我们现在从微米到露头尺度。近年来，这些基本过程的复杂性和相互关系受到了更多的关注，尽管它们的影响似乎仍然被低估了。是富含碳酸盐沉积物的这些变化发生在很早的时候，埋藏深度很浅（十米或更小），影响了我们现在从微米到露头尺度的观察。近年来，这些基本过程的复杂性和相互关系受到了更多的关注，尽管它们的影响似乎仍然被低估了。是富含碳酸盐沉积物的这些变化发生在很早的时候，埋藏深度很浅（十米或更小），影响了我们现在从微米到露头尺度的观察。近年来，这些基本过程的复杂性和相互关系受到了更多的关注，尽管它们的影响似乎仍然被低估了。