log(Q/K) VS. T表示什么意思

gousheng12345

看到某些文献里面画出来的log(Q/K) VS. T图不明白是干什么用的，请大家指教，谢谢！

下面是某篇文献的摘要的介绍部分（由于我下载不了全文，给出原摘要位置 http://www.sciencedirect.com/science/article/pii/0016703784904046 ），请大家解释下这段话是什么意思
This calculation provides accurate values for the activities of aqueous ions in a given water at high temperature, which are used to calculate an ion activity product (Q) for each of more than 100 minerals. The value of log(Q/K) for each mineral, where K is the equilibrium constant, provides a measure of proximity of the aqueous solution to equilibrium with the mineral. By plotting log Q / K vs . T for natural waters, it is possible to determine: a) whether the water was in equilibrium with a host rock mineral assemblage, b) probable minerals in the equilibrium assemblage and c) the temperature of equilibrium.

如果我也想作出来同样的图，该怎样去实现呢？谢谢