まとめ
ドルミチ化,すなわちカルシットとアラゴニットをドルミットに置き換えることは,低硫酸塩と最小限のシリカのダイアゲネシスの海と湖の環境で起こります. シリカからクォーツへの変換はドロマイト形成を好み,オパール-Aからオパール-CTへの変換はそれを阻害する.
科学分野:
- 地質化学 地質化学
- 堆積物学 堆積物学 堆積物学 堆積物学 堆積物学
- ミネラロジーは,鉱物学です.
背景:
- ドロマイトの形成は,炭酸塩のダイアゲネシスの理解に不可欠です.
- ドロミチ化の環境条件は,依然として重要な研究分野です.
- シリカダイアゲネシスは,炭酸塩鉱物の変換に影響を与えることができます.
研究 の 目的:
- ドロマイト形成に有利な条件を実験的に調査する.
- ドロミチ化における硫酸塩濃度とシリカダイアゲネシスの役割を明らかにする.
- オパール-Aからオパール-CT,オパール-CTからクォーツの変換がドロマイトの降水に与える影響を決定するために.
主な方法:
- カルシートとアラゴナイトの代替実験を制御された条件下で実施.
- 溶解した硫酸塩の濃度が多様です.
- オパール-A,オパール-CT,クォーツ変換を含む,操作されたシリカダイアゲネシスの段階.
主要な成果:
- ドロミチ化は,溶解硫酸塩濃度が低いことと,限られた同時シリカダイアゲネシスにより好ましい.
- 微生物による硫酸塩の減少と淡水と海水の混合により,低硫酸塩の良好な条件が生まれます.
- オパール-Aからオパール-CTへの変換は,ドロミット形成を阻害しますが,オパール-CTからクォーツへの変換は,それを促進します.
結論:
- ドルミチ化は,特定の地質化学的条件下で,海洋や湖の環境で実行可能である.
- シリカダイアゲネシスは,ドロマイトの降水を制御する上で,時間に依存する重要な役割を果たします.
- これらの過程を理解することは,古代炭酸塩堆積岩の解釈に不可欠です.
関連する概念動画
Factors Affecting Solubility
Compared with pure water, the solubility of an ionic compound is less in aqueous solutions containing a common ion (one also produced by dissolution of the ionic compound). This is an example of a phenomenon known as the common ion effect, which is a consequence of the law of mass action that may be explained using Le Chȃtelier’s principle. Consider the dissolution of silver iodide:
Deleterious Substances in Aggregate
Deleterious substances in aggregates can be detrimental to the quality and durability of concrete. These substances include organic impurities like loam, which interfere with cement hydration and are usually present in the sand. These prevent a good bond between aggregate and cement paste. Organic impurities can be detected using the colorimetric test, where the darkness of a solution after agitation indicates the level of organic content.
Another type of impurity is clay and fine material that...
Another type of impurity is clay and fine material that...
Solubility Equilibria: Overview
When a substance such as sodium chloride is added to water, it dissolves, forming an aqueous solution. The extent of dissolution is called solubility. The process of dissolution can exist in equilibrium, just like other chemical processes. Solubility equilibria are also called precipitation equilibria because the process of solubility can be reversible. The reverse of the solubility process is called precipitation.
Solubility is important in biological and environmental processes. A notable...
Solubility is important in biological and environmental processes. A notable...
Imperfections in Crystal Structure: Non-Stoichiometric Defects
Non-stoichiometric defects refer to a type of defect in the crystal structure of a compound where the ratio of its constituent elements deviates from the ideal stoichiometric ratio. There are two main types of non-stoichiometric defects: metal excess defects and metal deficiency defects.Metal excess defects occur when there is a slight surplus of metal ions than what is required by the stoichiometric ratio of the compound. For example, heating a sodium chloride crystal in sodium vapor results...
Ionic Crystal Structures
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Essential Minerals for Bone Health
The minerals contained in all of the food we consume are essential for our organ systems. However, certain essential minerals, such as calcium, phosphorus, magnesium, manganese, and fluoride, largely affect bone health.
Calcium and Phosphorus
Calcium is a critical component of bones, especially in the form of calcium phosphate and calcium carbonate. Since the body cannot make calcium, it must be obtained from the diet. However, calcium cannot be absorbed from the small intestine without...
Calcium and Phosphorus
Calcium is a critical component of bones, especially in the form of calcium phosphate and calcium carbonate. Since the body cannot make calcium, it must be obtained from the diet. However, calcium cannot be absorbed from the small intestine without...


