Study of sulphur material in carbonate rock areas

In recent years, due to the increase in the use and release of sulfur-containing substances worldwide, sulfur has become an important element in the formation of regional and global acid deposition, and the impact of sulfuric acid on regional and even global chemical weathering has gradually become prominent. With the increasing prominence of this problem, more and more scholars have paid attention to sulfur as a carbon source. Compared with the research of foreign scholars, there is still a lack of relevant research in China, and most of the studies on regional chemical weathering exclude the consideration of the participation of sulfuric acid.

China has a vast land area and extremely rich carbonate strata, and a large amount of atmospheric carbon dioxide is eliminated through the chemical weathering of rocks every year, which is an important carbon reservoir in the land system of the northern hemisphere. At the same time, the reserves of sulfur in China's environmental system are also relatively abundant, and from the stoichiometric point of view, sulfuric acid has become an important part of water chemistry in many river basins, which may indicate that sulfuric acid is involved in the chemical erosion of river basins, but the superposition effect of chemical weathering process and human activity input, as well as atmospheric input, makes this judgment need to be further supported by multi-faceted research. At the same time, whether sulfuric acid is involved in the erosion process of the watershed in the carbonate area is of great significance for us to correctly understand the chemical weathering rate of the watershed, as well as the atmospheric CO2 consumption and the global carbon cycle caused by the erosion of the watershed. In conclusion, as one of the important influencing factors affecting the carbon exchange between land and atmosphere, the study of the carbon source effect of sulfur in carbonate region has high theoretical and practical significance.

You can start with the distribution and types of sulphide minerals in sedimentary rock areas.

For example, pyrite nodules are common in coal seams and limestones.

There are also sedimentary copper deposits that are found in areas where carbonate rocks are distributed.

It is also possible to catch that the sulfur in the sedimentary type sulfide is reducing.

In this way, the paleoenvironment at that time was analyzed.

Or think about it in terms of the parent rock of the deposited massive or layered ore layer.

Anyway, I'm going to start with sulfur-containing minerals.

I don't know if it helps you.

The main hot water deposits are anhydrite, gypsum, and lazuli.

and barite. Gypsum and lapis lazuli in addition to solubility.

In addition to the difference (the solubility of lapis lazuli is lower than that of gypsum), its solubility increases with the increase of salinity and pressure, and decreases with the increase of temperature; The solubility of barite increases with the increase of hot water salinity, pressure, and temperature. Sulfate.

Brine is an important fluid type of shallow low-temperature thermal sedimentary deposits, which mainly exists in medium-low temperature origin of hydrothermal sedimentation or hydrothermal metasomatic deposits.

In general, barite and anhydrite are common in marine hydrothermal sediments, while lazurite and gypsum are the main sediments in continental hydrothermal sediments. The crystallization deposition temperature of sulfate is lower than that of carbonate.

Therefore, it is a low-temperature hot water sedimentary rock.

Barite rock is an important hydrothermal sedimentary rock, because barite itself is a useful mineral, so when its mineralization is rich and large-scale, it is also a useful mineral - barite mine.

In modern sediments, barite is enriched in deep-sea sediments and hydrothermal vent sediments, with the mid-ocean ridge being the most abundant area, and the sedimentary facies environment formed by it is shelf facies or deep-water shelf facies. The high organic matter content and regular horizontal bedding in the sediments reflect a closed-semi-closed stagnant environment in deeper water. Barite rocks are not easily formed in a reducing environment and can only be formed near the oxidation-reduction interface, such as the marginal slope zone of a basin.

The formation age of hot water barite rocks (mines) in China is mainly Sinian and Cambrian.

and the Aoqi Hail Buried Pottery Period, followed by the Mud Selling Basin Period.

and Triassic. The mineral composition of barite rock is mainly barite, which is relatively pure, and there are small or trace amounts of quartz, chalcedony, and pyrite.

Mimica, argillaceous, carbonate minerals and iron. Barite is mainly produced in the form of other-semi-automorphic granular and inlaid shapes. The rocks have microcrystalline-fine-grained structures, medium-coarse-grained structures, other-semi-automorphic granular structures (Fig. 10-16), mosaic structures (Fig. 10-17), chondrite structures (Fig. 10-18), and sometimes sparse polyporphyritic structures (Fig. 10-19).

The structure is mainly block-like, lamellar (Fig. 10-20), band-like (Fig. 10-21), and sometimes suture structure.

Fig. 10-16 Other granular structure and lamellar structure of barite rocks.

Gutan, Guangxi, orthogonal polarization, 132) quoted from Li Yi.

Figure 10-17 Fine-grained mosaic structure of barite rocks.

Guangxi chicken coop top, orthogonal polarization, 132).

Quoted in Li Yi, 2010).

Figure 10-18 Chondrite structure of barite rocks.

Gutan, Guangxi, orthogonal polarization, 88).

Quoted in Li Yi, 2010).

Fig.10-19 Speckle structure of barite rocks.

Guangxi chicken coop roof, orthogonal polarization, 88).

Quoted in Li Yi, 2010).

Fig.10-20 Stratigraphic structure of barite rock.

Guangxi Gutan) quoted in Li Yi, 2010).

Fig.10-21 Band-lamellar structure of barite rock.

Guangxi Gutan, orthogonal polarization).

Quoted in Li Yi, 2010).

Carbonate rocks are sedimentary rocks composed of autogenous carbonate minerals such as calcite and dolomite. Rocks dominated by calcite are called limestone, and rocks dominated by dolomite are called dolomite. Carbonate rocks are formed mainly in the ocean, with a few forming in terrestrial environments.

Carbonate rocks formed in the vast oceans of ancient times, accounting for about 20% of the distribution area of surface sedimentary rocks. Carbonate rocks in China are mainly distributed in the Sinian, Cambrian Ridge, Ordovician, Devonian, Carboniferous, Permian, Triassic and some Jurassic, Cretaceous and Tertiary marine strata, among which the most cherry and jujube in southwest China is developed.

Carbonate rocks are important oil storage rocks. Fifty per cent of the world's oil and gas is stored in carbonate rocks. Carbonate rocks are also often symbiotic with many solid sedimentary deposits, such as iron ore, bauxite, manganese ore, gypsum, rock salt, potash, phosphate rock, etc., and are the reservoirs of many metal layer control deposits, such as mercury, antimony, lead, zinc, copper, silver, nickel, cobalt, uranium, vanadium, etc.

Carbonate rock itself is also a very valuable mineral, which is widely used in construction, chemical industry, metallurgy and other aspects.

Carbonate rock belongs to the modern term, which refers to the general term of the rock composed of carbonate minerals formed by sedimentation, and it is mainly limestone and dolomite.

In the study area, multi-layered carbonate rocks are developed in the Taiyuan Formation and Benxi Formation, and there are as many as 8 layers in the Fengfeng mining area, which are called "lower shelf limestone", "large green limestone", "middle green limestone", "small green limestone", "Fuqing limestone", "mountain green limestone", "wild green limestone" and "one limestone", among which the two layers of limestone of "Daqing" and "Fuqing" are the most stable, followed by "Xiaoqing" and "Shanqing", and "off the shelf" and "Zhongqing" are the most unstable and sometimes missing. These carbonate rocks are predominantly biostrital argillite limestones, containing a large number of marine fauna fossils, and often have bioturbation structures at the rock level, varying in thickness. Therefore, it is named as the raw argillite limestone facies, which are mainly carbonate subtidal zone or confined platform deposits, and this type of lithofacies is distributed in the area of Well Xinge 4-Zhuanggu 1 in the north of the study area and in the south of Hebei Province.