Earth's fluids can be likened to the blood of the human body, transporting various substances that circulate through the Earth's different layers. They promote various phase changes and chemical reactions, facilitate elemental cycling, and expedite energy transfer, playing an exceptionally important role in all stages of the Earth's evolution.
At present and for some time in the future, humans, especially scientists, have to face two significant issues: human health and Earth's health. It is the mission of geochemists to tackle problems such as global change, C-H-O-S-N cycling, greenhouse gas reduction, ocean acidification, deep-sea chemistry, soil chemistry, heavy metal pollution control, the chemical interaction between life substances and non-life substances, mineralization of deep fluids, metamorphism, fluid-rock interaction, fluid inclusions, salt lake chemistry, water quality engineering, etc. (as shown in Fig. 1), all falling within the disciplines of ecology, environment, oceanography, and resource geochemistry. All these problems are closely associated with a common medium—Earth’s fluids, which are composed of water, gas, various ions, and organic molecules, which can be classified into numerous systems; we call it Earth’s Fluid Systems (EFS). In most cases, the major chemical components of Earth-fluid systems are similar, the theoretical methods of chemical thermodynamics share common grounds, and the experimental data overlap. All these problems need to calculate thermodynamic properties, such as solubility, phase equilibria, distribution ratio between different phases, activity or fugacity, density, PVT properties, mole volumes, isochores, dielectric constant, conductance, etc. under different pressure-temperature-composition (PTx) conditions. Such calculations are generally not easy for most geoscientists. Therefore, we decide to develop this website (Link: http://efs.idsse.ac.cn), or a calculation platform called, for world-wide scientists to use. It will facilitate various calculations as shown on the website itself.
Earth’s Fluid Systems
Currently, this website offers the ability to calculate several key physical and chemical properties of Earth's fluid systems. These include phase equilibrium or phase state, solubility, PVT, density, isochoric lines, fugacity, activity, chemical potential, conductivity, dielectric constant, and diffusion coefficient for various major fluid systems. However, the site is still in its early stages of development and will undergo continuous improvements over the long term. We encourage users to share their suggestions for expanding and enhancing this resource. For inquiries, please contact Zhenhao Duan at zduan@idsse.ac.cn or Haoran Sun at sunhr@idsse.ac.cn .
Moreover, we are actively engaged in molecular dynamics and Monte Carlo simulations of geofluids, deep-sea chemistry, and eco-thermodynamics. Our goal in this research area is to achieve a quantitative understanding of ocean chemistry and the ecological mechanisms at play, as outlined in the descriptions for each research area. Furthermore, a computational platform for fluid inclusion studies is accessible on this site.
Note: Earth’s-fluids refer to liquids and gases under Earth's environmental conditions. The main components include water (H2O), gases (CO2, CH4, C2H6, N2, H2S, NH3, Cl2, F, HCl, N2O, Ar, He, etc.), metal ions (such as Na+, K+, Ca2+, Mg2+, Fe2+, Fe3+, etc.), anions (such as Cl- 、SO42-、 HCO3- 、CO32- 、PO43-、HPO42-、CrO42- etc.), various complex ions composed of anions and cations (important complex ions amount to hundreds of types), natural organic molecules, and various synthetic fertilizers, pesticides, and chemical product molecules. seawater, lake water, brine, geothermal fluids, mine water, soil water, sewage, volcanic gases, mineral inclusions, petroleum, natural gas, shale gas, gas hydrates, ore-forming fluids, and metamorphic fluids are all examples of Earth’s fluids.