Carbonate rocks are the third group of rocks, after clays and clastic rocks, that composed the sedimentary cover of the Earth. They were, apparently, the first group for which a change in their mineral and, accordingly, chemical composition in the geological history of the Earth was established. R. Daly had already shown at the beginning of the twentieth century, in 1902, that in the Phanerozoic sequence of the United States, there was a change in magnesian carbonate rocks (dolomites) with limestones. Following the detailed works by A.B. Ronov [6], this statement was not only confirmed, but to a large extent characterized quantitatively.

Qualitatively or, perhaps, semi-quantitatively, it turned out that calcium carbonates prevailed in the Archean and subsequently were completely metamorphosed into calciphyres, marbles, and other similar formations. At the Archean–Proterozoic boundary, or, according to the modern geochronological scale, at the beginning of the Proterozoic (Siderian), there was a relative and, at the same time, significant formation of siderites in the composition of ferruginous quartzites (Fig. 1).

Fig. 1.
figure 1

The correlation scheme of the composition of carbonate rocks and the development of some autotrophic organisms in the geological history of Earth. The first milestone: the change of acidic environments of reservoirs to slightly acidic ones, the formation of iron carbonates, and the inland water reservoirs. The second milestone: the formation and flourishing of stromatolite-forming cyanobacteria that utilize CO2, and, as a consequence, by the change of slightly acidic environments of reservoirs to alkaline ones, the formation of Mg carbonates, and the inland water reservoirs. The third milestone: the disintegration and reduction of stromatolite-forming assemblages and, as a consequence, a sharp decrease in alkalinity and the scale of formation of magnesian carbonate rocks, as well as the first occurrence of skeletal fauna, the beginning of the formation of organogenic limestones, and the formation of relatively deep-seated sediments in the marginal parts of the paleoceans, where carbonate material was accumulated mainly in the form of nektonic organism skeletons. The fourth milestone: the beginning of the accumulation of deep-sea oceanic sediments proper, with the supply of carbonate material mainly in the form of planktonic skeletons, further displacement of microbial communities to the areas with abnormal hydrochemical conditions and, accordingly, reduction of dolomite formation. The fifth milestone: the main carbonate accumulation shifted to vast ocean with the supply of material in the form of planktonic organism skeletons, a sharp reduction of shelf carbonate accumulation of bentonogenic type.

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Since carbonate ores are less attractive in economic terms than oxide, magnetite–hematite ores, primary attention was paid to the latter, but the occurrence of carbonate ore varieties was not denied. There is even the idea that all ores were initially carbonate, and their present-day magnetite–hematite composition ores is a result of metamorphic transformations [1]. Whether this is true or not is not essential in this case. The presence of iron carbonates is the most important issue.

Siderite formation was followed by magnesian carbonates. Examples of the latter are the magnesites of the Goran Formation of Southwestern Pamir with an absolute age of >2 Ga and the Eastern Sayan magnesites of approximately the same age; Lower Proterozoic magnesites are known in Karelia, Northeast China, and other areas.

The quite fundamental changes in the composition of carbonate rocks occurred at the Proterozoic–Phanerozoic boundary. First of all, the formation of magnesian varieties sharply decreased. Moreover, such replacement of dolomites with limestones continued, with some deviations and the return of the formation of dolomites, during the entire Phanerozoic [3]. As noted above, this fact was established at the beginning of the twentieth century.

In parallel with the change in the composition of rocks, the areas of their formation also changed.

At the end of the Archean (2.6 Ga), the first “giant” carbonate platforms appeared, that is, quite thick, and, most importantly, significant in the area of distribution [5]. A similar situation occurred, apparently, during the entire Proterozoic.

As in the Archean, carbonate accumulation in the Proterozoic took place within the basins of the ancient platform. Some of these carbonate strata were significantly reworked and detached in subsequent epochs. As noted above, carbonate rocks were represented by essentially magnesian varieties (dolomites, magnesites) and their volume was at the same level as calcium varieties (limestones) and maybe even higher.

Fundamental changes occurred at the Vendian–Cambrian boundary.

First of all, skeletal fauna appeared, that is, a new biogenic way of separating carbonate matter into the solid phase in the form of skeletal organisms. Secondly, there is convincing evidence about the formation of carbonate strata beyond platform reservoirs in already apparently oceanic-type basins, as exemplified by carbonate build-ups, including reef-related ones, in the Altai–Sayan region. Strictly speaking, these structures, which are interpreted as oceans, apparently represent only the marginal parts of the ancient, now extinct oceans. Among them are the Proto–Panthalassa, Paleotethys, and Paleo-Asian oceans, as well as the Paleo-Uralian ocean, distinguished by Russian researchers as part of the Paleo-Asian ocean [2]. The oceans themselves are, rather, terra incognito, more precisely, marine incognito of the pre-Jurassic basins.

At the same time, a rather evident evolution of carbonate accumulation happened both in various areas of the oceans in terms of paleogeography and in the features of the carbonate–producing biota—organisms with a function of transformation of organic carbon according to V.I. Vernadsky.

Firstly, the mechanism of purely biogenic carbonate accumulation in the form of skeletal remains of organisms appeared and actively developed both quantitatively and qualitatively. Secondly, the microbial deposition continued to exist. It was consistently, although to a certain extent cyclically, reduced, being localized in water environments more or less abnormal in chemistry, different from those of the Middle Ocean. In particular, the latter was reflected in the quantitative reduction in the volume of dolomite accumulation.

In the Paleozoic, the main carbonate accumulation took place within the vast, generally shallow “shelf” seas covering ancient platforms. Thus, the Silurian seas with carbonate accumulation covered almost the entire North American continent from the Canadian Arctic Archipelago to Mexico, the Devonian and Carboniferous seas, the Eastern European Platform, etc.

It should be emphasized that along with the subsequent Mesozoic and, especially, Cenozoic basins, there appeared new oceanic areas of carbonate accumulation, where the skeletons of predominantly nekton organisms became a significant supplier of material. These are, for example, Upper Silurian orthoceras limestones of the Carnic Alps; Ludlovian cephalopod limestones and Ordovician cellular limestones of the Urals; and Devonian–Lower Carboniferous flaser limestones of Spain, France, Central Europe, the Urals, Kazakhstan, and other areas. Actively floating cephalopods—goniatites in the Paleozoic and ammonites in the Mesozoic—were very important, and perhaps the main suppliers of carbonate material in these areas. The importance of planktonic organisms—pteropods, foraminifera, coccolithophorids, etc.—sharply increased beginning from the second half of the Mesozoic, and in reality, since the Cretaceous period and in the Cenozoic; oceanic carbonate accumulation here became predominantly planktogenic.

Vast shoals in oceans, where benthic organisms were the main supplier of the material, were the third area of carbonate accumulation. These are, for example, the Upper Silurian–Lower Carboniferous deposits of the Nyurol and Khanty-Mansi structural facies zones of Western Siberia, the Devonian deposits of Altai and Salair, the Paleozoic deposits of the Ustyurt plateau, the Famennian–Tourneasian of the Kazakhstan shoal, and a microcontinent within the Proto- and Paleothethys. Finally, reefs within intracontinental depressions, framed by the platform shallow “shelf” seas in the zone of their transition to deep ocean areas, as well as individual buildups and their groups directly in the oceans, were the fourth area of carbonate accumulation.

Very significant rearrangements occurred in the Mesozoic and Cenozoic. Carbonate accumulation in the seas covering the ancient and young Hercynian platforms decreased sharply, if not very sharply. Skeletal remains of benthic organisms became the main supplier of carbonate material. The exception was the Cretaceous period, when coccolithophorids were common in both oceanic and marine basins, and the chalk deposits formed by them were accumulated within water reservoirs of different tectonic positions, but in zones of generally warm, less often, apparently temperate climate.

The main carbonate accumulation shifted toward the oceans and marginal seas. Moreover, it was largely due to the flourishing of ammonites and belemnites in the Triassic and Jurassic. Later, carbonate accumulation was determined by the development of planktonic organisms—coccolithophorids, pteropods, and various groups of foraminifera.

At the same time, carbonate accumulation occurred on a much smaller scale within the intraoceanic shoals, which are described as isolated carbonate platforms (Bahamas, Seychelles, Maldives). Here, apparently, the relative proportion of reef carbonates increased.

Such a distribution of the types of carbonate deposits indicates not only certain changes in the mechanisms and ways of carbonate accumulation, but also the evolution of the conditions of carbonate accumulation, both geochemical and, what should be noted especially, paleogeographic, and hence indirectly and partly in terms of paleotectonics.

Summarizing the data on the distribution of types of carbonate deposits over time and interpreting the conditions for the formation of certain rock varieties, it is possible to outline a number of milestones in changing the conditions of their accumulation, both geochemically and paleogeographically, and hence partly in terms of paleotectonics.

A rather large body of evidence indicates predominantly acidic environments in the Archean, which in principle was not favorable for carbonate accumulation, but contributed to intensive chemical weathering and, in particular, the conversion of iron into a soluble form, that is, the mobilization of this element and its active migration.

The situation in the Early Proterozoic terminal basins was somewhat different, and iron was deposited in weakly acidic environments in the form of siderite and sideroplesite. In principle, it is not so important whether all the iron was deposited in the carbonate form and, subsequently, part of it was oxidized in the processes of metamorphism, or if there was a parallel deposition of both forms in different parts of the basins. Firstly, it is important that the general geochemical situation changed from acidic to weakly acidic; secondly, the appearance of free oxygen at this time, at least in water reservoirs, is a phenomenon called the Great Oxidation Event (2.47–2.32 Ga). So, the first milestone in the evolution of carbonate accumulation was the Archean–Proterozoic boundary, characterized by the development of slightly acidic and oxidative environments in water reservoirs.

The second important milestone is the boundary of two early periods of the Proterozoic–Siderian and Rhyacian.

According to M.A. Semikhatov and M.E. Raaben [6, 7], it was at this time, 2.3–2.0 Ga, that the first mass occurrence of cyanobacterial communities took place, and, as a consequence, the active development of various stromatolites. This led to intensive CO2 utilization. In the interval of 2.3–2.1 Ga, the Lomagundi Event, a positive anomaly of δ13C marked a massive supply of oxygen, that is, the formation and stabilization of oxidation environments in the Proterozoic. As a consequence, the acidic or slightly acidic environments in the Archean were rapidly followed by substantially alkaline ones in the Early Proterozoic, which led to the formation of carbonate deposits of already magnesian composition. Similar, mainly alkaline, environments with various fluctuations existed during practically the entire Proterozoic.

The third milestone is the Vendian–Cambrian boundary and, especially, the Vendian—Cambrian, which was characterized by a break and sharp reduction of stromatolite-forming communities and the first occurrence of skeletal biota with carbonate secretions in the form of external and internal skeletons. At this time, the displacement of microbial communities into specific environments of arid coasts, littoral bays, and lagoons with hydrochemical regimes different from marine conditions began. The dolomite accumulation was displaced to the same areas and was simultaneously reduced.

Important paleotectonic, and hence paleogeographic, changes occurred simultaneously with the change in the geochemical conditions—the appearance of oceans and the displacement of carbonate accumulation towards them, at least partially.

At the same time, the areas of carbonate accumulation noted above were finally formed. These are extensive Paleozoic shelf zones, which apparently prevailed in the overall balance of carbonate accumulation; isolated carbonate platforms in the oceans with benthic carbonate accumulation, reefs of two types (shelf zones bordering the deeper ocean regions, and single ones, relatively symmetrical in cross section, in deep-water zones).

The fourth, apparently less significant milestone was the Paleozoic–Mesozoic boundary, which was characterized by a significant deepening of the oceans, an increase in the role of nekton organisms in the carbonate accumulation, and the accumulation of deep-sea carbonate sediments.

Finally, the fifth milestone is the beginning of the Cretaceous period, when the role of planktogenic carbonate sediments in the oceanic sector of the planet sharply increased. At the same time, the shelf carbonate accumulation (excluding that in the Cretaceous period) and, apparently, shallow benthic accumulation in shallow areas of the oceans significantly decreased.