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Geologic Principles
Published in Stephen M. Testa, Geological Aspects of Hazardous Waste Management, 2020
Carbonate rocks are defined as containing more than 50% carbonate minerals. The most common and predominant carbonate minerals are calcite (CaCO3) and dolomite [CaMg(CO3)2]. Other carbonate minerals include aragonite (CaCO3), siderite (Fe12CO3), and magnesite (MgCO3). The term limestone is used for those rocks in which the carbonate fraction is composed primarily of calcite, whereas the term dolomite is used for those rocks composed primarily of dolomite.
Nature and Distribution of Cavities within the Ma on Shan Marble at Area 90 – Hong Kong
Published in Ömer Aydan, Takashi Ito, Takafumi Seiki, Katsumi Kamemura, Naoki Iwata, 2019 Rock Dynamics Summit, 2019
In carbonate rocks, a significant part of soil-CO2 is dissolved in infiltration water, produces acidic water and dissolves the carbonate rock. However, the concentration of CO2 is mainly controlled by plant roots and the respiration of microorganisms as well as organic matter decomposition which depends on climate, season and nature of soils and can vary within a certain range (Jeannin P.-Y. et al. 2016).The amount of water available to dissolve the calcitic rock mass can vary tremendously and it is the main controlling factor in the dissolution process (Chan Y.C. 1989). Flow rates and the water’s aggressiveness (degree of chemical saturation) mainly determine rates of cave enlargement, which originates on bedding planes and tectonic fractures (Lowe D.J. 2000).
Groundwater environments
Published in Ian Acworth, Investigating Groundwater, 2019
Sedimentary carbonate rocks are composed of calcite, aragonite or dolomite. They have great economic significance as reservoir rocks for gas, oil and water. They also have use in agricultural lime, cement, building stone and concrete aggregate. Chalk has been quarried from prehistory, providing building material and marl for fields. Modern coral reefs form major tourist attractions.
Study on multi-field catastrophe evolution laws of water inrush from concealed karst cave in roadway excavation: a case of Jiyuan coal mine
Published in Geomatics, Natural Hazards and Risk, 2021
Bo Li, Xianqing Wang, Zijie Liu, Tao Li
With an annual production capacity of up to 600,000 tons, Jiyuan coal mine is located 7 km away from the downtown area of Tongzi county, Guizhou province, China. Its geographic location is shown in Figure 1. Topographically, Jiyuan coal mine is high in the northeast and low in the southwest, with the highest elevation point of 1321.3 m and the lowest elevation point of around 565 m. A vast area of carbonate rocks is exposed on the surface of the mining field, where well-developed surface and underground karst landscapes in various types and diverse individual forms are present. Located across the monsoon climate zone, the mining field has a warm, moist climate and an annual average precipitation of 1011.2 mm over the past decade, with the majority of precipitation falling from May to October. The supply source of water is mainly the meteoric water, and highly frequent mutual exchange, conversion and circulation between surface water and groundwater are present there.
Indications of the sedimentary environments by the sedimentary characteristics and trace elements of Ordovician Majiagou Formation, Northern Shaanxi salt basin
Published in Geosystem Engineering, 2020
LinLin Wang, Tao Shi, Dawei Chang, Haitao Zhang
Combining the regional structure and sedimentary background, core observation and rock slice identification from 8 wells were carried out, including Zhen Jia Well 1 and Shaanjia Well 1. The results show that sedimentary rocks in Ordovician Majiagou Formation is mainly carbonates and evaporites (Figure 2). Other sedimentary rocks such as clastic rocks are less developed. Carbonate rocks include limestone and dolomite. The limestone is further divided into particle-lime mudstone and metasomatic limestone, and dolomite is further divided into dolomicrite, dolosiltite, saccharoidal dolomite, concrete-anhydrock dolomite, and lamellar gypsodolomite. The evaporites include gypsum rock and salt rock, and the gypsum rock is subdivided into primary gypsum rock and metasomatic gypsum rock. There are some bedding and sedimentary structures in the carbonate formation of Majiagou Formation, mainly including horizontal burrows, biological burrow structure, stromatolite structure, filling structure, horizontal bedding, deformed bedding and massive bedding. Based on the identification of rock types, beddings and sedimentary structures, the sedimentary facies types on Majiagou Formation carbonate platform in the study area are established, and the platform is further classified into open platform and restricted platform.
Properties and sustainability of concrete containing fillers*
Published in Australian Journal of Civil Engineering, 2018
Moetaz El-Hawary, Khallad Nouh
Dolomite and limestone are considered carbonate rock. They are sedimentary rocks which can be grinded and used as a partial replacement for cement. Using dolomite as a partial replacement of cement to produce Portland Dolomite Cement (PDC) decreases the amount of cement which in turn reduces the CO2 emissions (Preethi and Prince 2015). Its use is not as common as limestone and research studies on the properties of dolomite as a partial cement replacement are limited (Szybilski and Nocuń-Wczelik 2015). Some energy is consumed in the grinding process. This, however, is negligible compared to the savings in the amount of cement which is an energy intensive material. It is estimated that about 1 ton of carbon dioxide is produced per one ton of cement (Sadek, Amin, and Youssef 2014). Fillers may be also collected as byproducts of the crushing process of rocks to produce aggregates.