Editorial for Special Issue “Life and Carbonate: Biotic and Abiotic Fingerprints in Past and Recent Carbonate Sediments”

Carbonate sedimentary systems represent one of the best examples of interactions between the biosphere and the geosphere throughout geologic time. Organisms often play key roles in carbonate mineral formation and the depositional processes of carbonate sediments. On the other hand, carbonate sediments and rocks are fundamental components of natural systems and have influenced the environments and biogeochemical cycles during the Earth’s history. Therefore, the study of carbonate systems can contribute to several aspects of both Life and Earth Sciences, as it is linked to environmental and geological processes and the activity and evolution of organisms. In addition, carbonate systems host some of the most important natural resources, so they are also relevant for more applied branches, such as the characterization and exploration of aquifers and hydrocarbon reservoirs.

While carbonate sediments form and deposit on the Earth’s surface, they can also change significantly after deposition, due to the interplay of various physical and chemical processes occurring in the subsurface. Thus, carbonate sedimentary systems are derived from a complex history that connects the surface and the interior of the Earth’s crust, which makes them extremely variable from sedimentological, stratigraphic, structural, mineralogical, and chemical perspectives. For this reason, studying carbonate systems is challenging and requires the integration of different approaches and techniques of various disciplines, such as sedimentology, stratigraphy, paleontology, geochemistry, geobiology, among others.

This Special Issue contains six contributions presenting advancements on various aspects of carbonate systems. Two focus on shallow water carbonate platforms, investigating the facies associations and the depositional architecture of two depositional systems: one in Egypt [1] and the other in Iraq [2]. Although based on traditional methodologies, these studies base their interpretation on modern concepts of sedimentology and stratigraphy, highlighting how the evolution of these carbonate systems is controlled by ecological conditions, the type of carbonate-producing organisms that lived in the respective periods, and the interplay between environmental and geological factors, such as tectonics, sea level, and climate.

Two other contributions focus on the role of microbial communities in the formation of carbonate sediments. Leapaldt et al. [3] undertake an experiment that shows how the chemical composition of some trace metals and phosphorus can be indicative of a biogenic origin, especially related to cyanobacteria. Ingrassia et al. [4], instead, investigate the role of extracellular polymeric substances (ESPs) produced by microorganisms that induce carbonate precipitation in association with Mg-smectite in an alkaline lake environment. These studies present advanced approaches integrating sedimentological, mineralogical, geochemical, and microbiological information to provide a comprehensive view of the mutual control that environmental conditions and microbial communities can have on the depositional processes.

The last two contributions address the influence of dolomitization on sedimentological and geochemical properties in carbonate successions. Adlan et al. [5] describe how burial temperatures estimated with clumped isotopes in a specific stratigraphic unit can vary depending on the mineral phases, as dolomite has different kinetic parameters than calcite and, therefore, responds differently to the diagenetic alteration during burial. On the other hand, Zhong et al. [6] reveal two kinds of dolomite formation, with distinct textural, crystallographic, and geochemical features. The two types of dolomites occur at different intervals of a stratigraphic sequence and can be related to different environmental conditions and early diagenetic processes that took place during different sea-level phases. These new insights into dolomite occurrence and formation in carbonate successions contribute to advancing the interpretation of carbonate facies.

Finally, it is important to stress that the works of this Special Issue are from authors across different countries and institutions. We selected some of the main keywords of these contributions and made a bibliometric analysis on Scopus (https://www.scopus.com/search) (accessed on 15 May 2025) dolomite” OR “carbonate facies” OR “biomineralization” OR “carbonate geochemistry” OR “carbonate petrology” OR “carbonate platform” OR “carbonate biosignature”. We obtained 1234 results, mainly articles, but also reviews, book chapters, conference papers, and others. Of these documents, 947 were published in the last decade (2015–2025), whereas less than a third (296) were published in the previous one (2005–2015). The United States is by far the country with the most publications; however, its contribution in percentage has decreased in the last decade compared to the previous one (24.11% in 2015–2025 vs. 31.44% in 2005–2015). Moreover, in the last decade, the number of subject areas that have published on carbonate topics has slightly increased (21 against 19), and the percentage of publications related to “Earth and Planetary Sciences” has decreased compared to other areas (39.70% vs. 44.79%). This indicates that the interest in carbonate systems is rising and stimulating scientific research at the interdisciplinary level and worldwide. Therefore, it is our hope that more important progress will be made in this field soon.