Structural or chemical transformations in minerals are driven by changes in the physical and/or chemical environment and in thermodynamic terms are the result of transforming the system to a new equilibrium.In many ca...Structural or chemical transformations in minerals are driven by changes in the physical and/or chemical environment and in thermodynamic terms are the result of transforming the system to a new equilibrium.In many cases,the chemical environment is changed by the introduction of an aqueous fluid whose composition is not in equilibrium with the solid mineral phase.In the Earth's crust such fluids may be saline(Na-rich)so that for example when a potassium-rich mineral such as orthoclase KAlSi3O8 comes into contact with a saline solution the thermodynamics dictates that there should be exchange of K for Na in the solid mineral resulting in the formation of albite Na AlSi3O8,a process known as albitisation,with the potassium removed to the fluid phase.展开更多
文摘Structural or chemical transformations in minerals are driven by changes in the physical and/or chemical environment and in thermodynamic terms are the result of transforming the system to a new equilibrium.In many cases,the chemical environment is changed by the introduction of an aqueous fluid whose composition is not in equilibrium with the solid mineral phase.In the Earth's crust such fluids may be saline(Na-rich)so that for example when a potassium-rich mineral such as orthoclase KAlSi3O8 comes into contact with a saline solution the thermodynamics dictates that there should be exchange of K for Na in the solid mineral resulting in the formation of albite Na AlSi3O8,a process known as albitisation,with the potassium removed to the fluid phase.
