化学沉积过程中元素间线性关系的研究──以盐类沉积为例

Research on Linear Relationships Between Elements in Chemical Sedimentary Process──Taking Saline Deposits for Example

本文研究了半封闭体系的盐类化学沉积过程。在获得单个元素浓度变化规律的基础上，推导了元素间线性关系的数学模型。提出元素定性分配系数和定量分配系数概念，给出元素拟合直线截距和斜率的地球化学意义，并讨论了制约元素间关系的影响因素。最后给出了应用实例。

On the bests of study of geochemical behavior of sin81e elements,the paper has established a mathematic model for linear relationships between elementS in the chemical sedimentary process of a semi-closed system:which is very similar to that of magmatic fractional crystallization (Wan Yusheng, 1990). In the formula, C C and C C represent the contents of elements x and y in original saturated solution and reSidual satuxated solution respectively, Dx and Dy are bulk distribution coefficentS of x and y ,Fi is reSidual ratio of saturated solution, and t is solute proPOrtion in saturated solution. Example shave also been given to show how to apply the method to research on saline sedimentation. Following are some main conclusions:1) The regression line representS the result of the linear regression of a cutve with lesscurvature. Foe an incompatible element-fair, the more similar the properties of two elements andthe smaller their bulk distribtition coefficientS are, the better the regresion line is.2)The nit6rcept and slope of the regression line have clearly geochemical significance.Both ofthem are constituted by the P8rametCrs C,C, Dx, Dy, t and Fl.If x and y are incompatible, then the slope of the line will be active and the line will intersect a relatively compatible element axis.When D values of x and y are similar, the intercept and slope of the regression line are close to zeroand C/C respectively.3)There could be different degrees of linear correlations between two elements of elementpair at different stages of evolution of the saline water, resulting from asynchronous variations ofthe bulk diStribution coefficients of the elements. And in different saline water systems, the sameelement-pairs can represent different degrees of linear correlations, so the chemical compositions of the systems will strongly influence the geochemical behaviors of the elements.