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The Geosphere and Geochemistry
Published in Stanley E. Manahan, Environmental Chemistry, 2022
Evaporites are soluble salts that precipitate from solution under special arid conditions, commonly as the result of the evaporation of seawater. The most common evaporite is halite, NaCl, and another example is anhydrite, CaSO4. Many evaporites are hydrates, including gypsum (CaSO4•2H2O). A very important hydrated evaporite is trona, Na2CO3•NaHCO3•2H2O, which occurs in huge deposits in the US state of Wyoming and, in the United States, has replaced the long-established Solvay process that produces large quantities of by-product CaCl2 waste.
Geology of Urban Watersheds
Published in Daniel T. Rogers, Urban Watersheds, 2020
Common evaporite deposits include halite and gypsum. All water bodies on the surface and in aquifers contain dissolved constituents including salts. For an evaporite deposit to form, the water must evaporate into the atmosphere, causing the minerals dissolved in the water to precipitate. Evaporites generally form when water accumulates in closed basins in arid and semi-arid environments. Enclosed basins in arid environments are favored because they provide high evaporation rates due to low humidity and lack an outlet for the water to drain, which essentially traps the water. Examples of extensive evaporite deposits include areas in and around the Great Salt Lake of Utah and parts of Nevada
Mineral Deposits
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
Evaporite deposits have formed in many arid continental regions around the world. Chapter 8 briefly discusses examples of such deposits associated with Utah’s Great Salt Lake and California’s Searles Lake. Most continental evaporite deposits form when water flows into an intermontane (between two mountain ranges) valley, creating shallow ephemeral lakes that evaporate quickly. In some places, seasonal variations in rainfall mean that precipitation of evaporite minerals only occurs during dry months. The minerals deposited in continental evaporites are different from those deposited in marine evaporites, because the compositions of continental and marine waters are different. However, calcite, gypsum, and halite are generally dominant in both settings. And many other minerals, especially boron- and lithium-containing minerals, that crystallize during evaporation in closed drainage basins are important resources for society.
Influence of halite particles on the stability and physical properties of inverse olefin emulsions
Published in Particulate Science and Technology, 2023
Anna Carolina Amorim Costa, Waleska Rodrigues Pontes da Costa, Luciana Viana Amorim, Renalle Cristina Alves de Medeiros Nascimento, Karine Castro Nóbrega, Ruth Luna do Nascimento Gonçalves
The presence of evaporite rocks is associated with many well stability problems, due to the very soluble nature of the minerals, as well as due to the mobility and creep characteristics of these rocks (Carcione, Helle, and Gangi 2006; Pasic, Medimurec, and Matanovic 2007; Omojuwa, Osisanya, and Ahmed 2011). Synthetic-based drilling fluids (SBM) have been identified by most operators and service companies as the most suitable for drilling this type of formation (Falcão 2009). These fluids have advantages regarding the solubility of salt formations, since they are based on inverse emulsions, in which the aqueous phase is emulsified in an organic base, thus constituting the internal phase of the emulsion.In addition, these fluids are less toxic and more degradable in marine sediments (Mairs et al. 2000; Ghalambor, Ashrafizadeh, and Nasiri 2008; Stout and Payne 2017).
Potassium-bearing species in fertiliser obtained by hydrothermal modification of glauconitic siltstones with calcium hydroxide
Published in Mineral Processing and Extractive Metallurgy, 2022
Rodrigo A. O. Peixoto, Kátia D. Oliveira, Cícero N. Ávila-Neto
Evaporite deposits are the main and most important sources of potassium salts. Salts derived from these deposits have high potassium contents, are very soluble in water, and can be easily processed and exploited. The main evaporitic minerals are silvite (KCl), carnalite (KCl·MgCl2·6H2O), kainite (KCl·MgSO4·3H2O), and langbeinite (K2SO4·2MgSO4). Silvinite and carnalite are the most exploited minerals as sources of potassium (Brazil 2001). Potassium salts are primarily used in agriculture, providing one of the three essential elements (N, P and K) for agricultural production. More than 95% of world potash production is used as fertiliser, of which 90% is in the form of KCl, followed by K2SO4 and others (Brazilian Mining Association 2012). Canada, Belarus, and Russia are the leading countries in potash reserves, as well as the largest producers, occupying the top three positions in the world ranking. Together, these countries accounted for around 59% of global potash fertiliser production in 2016 (Brazil 2019).
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.