地质流体热力学模型

        地球流体是指地球环境条件下的液体和气体， 主要成分包括水（H₂O）、气体（如CO₂、CH₄、C₂H₆、N₂、H₂S、NH₃、Cl₂、F、HCl、N₂O、 Ar、He等）、金属离子（如 Na⁺、K⁺、Ca²⁺、Mg²⁺、Fe²⁺、Fe³⁺等）、 阴离子（如Cl^- 、SO₄^2-、 HCO₃^- 、CO₃^2- 、PO₄^3-、HPO₄^2-、CrO₄^2-等）、各种阴离子和阳离子组成的络合离子（重要的络合离子达数百种）、天然有机分子和各种人工合成化肥、农药、化学用品分子等， 这些组分形成了一元、二元、三元和多元体系， 所以流体体系的种类繁多，但是常见的流体只包括几十种，其实，其它行星流体也包括在这个范围内。

        海水、湖水、卤水、地热液体、矿坑水、土壤水、污水、火山喷发气体、矿物液体包裹体、板块俯冲带脱水脱碳产生的流体、温室气体、石油、天然气、页岩气、气体水合物、成矿流体、变质流体等等也是地球流体。几乎所有的地球化学过程都离不开地球流体的参与。 定量计算流体的热力学性质（PVTx性质、密度、等容线、化学位、溶解度、相变、热容、热焓等）对于定量分析地球化学过程非常重要。

        过去几十年来，我们针对多种地球流体体系，系统建立并发展了一系列状态方程和热力学模型。相关成果已被全球688所顶尖高校或科研机构的逾万名科学家，广泛应用于固碳、矿床形成、海洋科学、环境保护、资源勘查及生态演化等领域的理论与实验研究（详见：https://efs.idsse.ac.cn/module1/citation.html）。

        本网站提供一个便捷的在线计算平台，用于高效计算多种热力学性质。平台所采用的地球流体热力学模型或状态方程均已在学术界获得广泛正面引用，并力求以最友好、直观的界面服务于广大科研工作者。该计算平台将持续更新与完善，未来将纳入更多类型的地球流体体系及热力学性质，以更好地满足科学研究需求。

        我们正在编写《流体地球化学》一书， 参见目录。

Thermodynamic Models of Geological Fluids

    Geological fluids refer to liquids and gases under Earth's environmental conditions. Their main components include water (H₂O), gases (such as 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^-, SO₄^2-, HCO₃^-, CO₃^2-, PO₄^3-, HPO₄^2-, CrO₄^2-, etc.), various complex ions composed of anions and cations (with important complex ions numbering in the hundreds), natural organic molecules, and various synthetic molecules from fertilizers, pesticides, and chemical products. These components form unary, binary, ternary, and multicomponent systems, resulting in a wide variety of fluid systems. However, common fluids only include a few dozen types。 Fluids from other planets also fall within this range.

    Seawater, lake water, brine, geothermal fluids, mine water, soil water, sewage, volcanic gases, mineral fluid inclusions, fluids from dehydration and decarbonation in subduction zones, greenhouse gases, petroleum, natural gas, shale gas, gas hydrates, ore-forming fluids, and metamorphic fluids are all considered geological fluids. Almost all geochemical processes involve the participation of geological fluids. Quantitative calculation of the thermodynamic properties of fluids (PVTx properties, density, isochoric lines, chemical potential, solubility, phase transitions, heat capacity, enthalpy, etc.) is crucial for the quantitative analysis of geochemical processes.

    Over the past several decades, we have systematically developed and refined a series of equations of state and thermodynamic models for various geofluid systems. Our work has been widely adopted by over 10,000 scientists from 688 leading universities and research institutions worldwide, and applied in both theoretical and experimental studies across fields such as carbon sequestration, ore deposit formation, marine sciences, environmental protection, resource exploration, and ecological evolution (for details, see: https://efs.idsse.ac.cn/module1/citation.html).

    This website provides a user-friendly online computing platform for the efficient calculation of a wide range of thermodynamic properties. The geofluid thermodynamic models and equations of state employed on this platform have been extensively and positively cited in the academic literature, and we strive to offer researchers the most intuitive and accessible interface possible. The platform will be continually updated and improved, with plans to incorporate additional geofluid systems and thermodynamic properties in the future to better serve the needs of the scientific community.

Close

流体包裹体研究

        本计算平台提供了一些重要地质流体体系包裹体计算工具。 请流体包裹体研究的专家贡献新的模型， 我们尽量协助将模型转化为易于使用的计算工具。

Fluid Inclusion Research

    This computational platform provides some important thermodynamic calculation tools for geological fluid inclusion systems. We invite experts in fluid inclusion research to contribute new models, and we will do our best to assist in converting these models into user-friendly computational tools.

Close

深海地球化学

        既然选择了远方，我们便只顾风雨兼程；

        既然选择了海洋，我们便只有乘风破浪！

        汪品先：“在海洋面前，我们只是小学生。”那么，在深海面前，我们只是幼儿园孩子。

        丁抗：“深海本没有路，我们无须效仿，我们就是道路。”

        在深海地球化学方面，我们仍然懂得极少。深海是一个低温高压环境，在这里发生的化学反应的机制必然不同于常温常压或高温高压环境，比如，在表层海洋的碳酸盐过饱和可以析出方解石或霰石，在深海条件下不饱和, 则发生溶解， 这一从析出到溶解的变化完全改变了海洋的演化历史、全球碳循环和全球气温的变化；深海是一个海水与海底沉积物、海底热液、火山、岩浆，洋壳、气体或气体水合物相互作用的环境， 其化学环境和热力学机制必然不同， 比如，国际上广泛使用的地球化学软件如SUPCRT计算深海条件下矿物的溶解度，产生成倍的误差； 在深海，暗色生物网依赖的是地热和化学物质（如H₂S），其生物地球化学必将不同于依赖阳光的生物生态环境。 所以，深海地球化学尚有许多模拟和模型的“道路“需要深海人去探讨。

        深海化学只是我们计划研究的一部分。 “数字海洋系统“则是未来工作的总蓝图 （见下图）。

Deep-sea Geochemistry

    Since we aim at the distant land, we must ordeal rains and winds;

    Since we choose the vast ocean, we must navigate waves and tides!

    Wang Pinxian: "In front of the ocean, we are just elementary school pupils." Then, in front of the deep-sea, we are merely kindergarten children.

    Ding Kang: "There is no path in the deep sea; we do not need to follow others, we are the path."

    In terms of deep-sea geochemistry, we still know very little. The deep sea is a low-temperature, high-pressure environment where the mechanisms of chemical reactions must differ from those at normal temperature and pressure or high temperature and pressure. For example, in the surface ocean, carbonate supersaturation can precipitate calcite or aragonite, but under deep-sea conditions, it becomes undersaturated and dissolves. This transition from precipitation to dissolution completely changes the evolutionary history of the ocean, the global carbon cycle, and global temperature changes. The deep sea is an environment where seawater interacts with seabed sediments, hydrothermal vents, volcanoes, magma, oceanic crust, gases, or gas hydrates, and its chemical environment and thermodynamic mechanisms must be different. For instance, widely used geochemical software like SUPCRT produces significant errors when calculating mineral solubility under deep-sea conditions. In the deep sea, the dark biological network relies on geothermal energy and chemical substances (such as H2S), and its biogeochemistry must differ from the sunlight-dependent biological ecological environment. Therefore, there are still many "paths" of simulations and models in deep-sea geochemistry that need to be explored by deep-sea researchers.

    Deep-sea chemistry is only part of our planned research. The "Digital Ocean System" is the overall blueprint for future work.

Close

生态热力学创新研究

        生态系统是由非生物物质（水、气、离子、有机分子、络合物、矿物、胶体、人工合成化合物）和生物（微生物、植物、动物、人类）组成的相互作用的非线性复杂系统。“生态热力学“是一门以平衡热力学和非平衡热力学为基础的、将生物和非生物放在平衡热力学和不可逆热力学框架下研究生态系统物质流和能量流及其演化的科学；是一门从定性认识到宏观热力学变量定量描述生物—非生物相互作用的科学，是一门对于生态建设、固碳技术、污染治理、农林种植、海洋生态全球变化研究具有重要指导意义的科学。

        “大道至简，演化至繁“。以熵作为出发点，以经典热力学和不可逆热力学作为理论基础， 生态热力学推导了两条原理，一条是非生物自由能最低平衡热力学原理，另一条是生物能量最大化非平衡热力学原理，通过耦合这两条原理，生态热力学描述了生物与非生物相互作用的机制，试图建立跨越无机—有机，非生物—生物、平衡—非平衡、自然—人文、过去—未来相互关联的交叉科学。为我们分析微生物、植物、动物和人类的行为性质和生态演化规律奠定基础。

        详见《生态热力学》一书： 段振豪著 （预计2026年出版）和《简介》。

Innovative Research in Ecological Thermodynamics

    Ecosystems are nonlinear complex systems composed of interacting abiotic substances (water, gases, ions, organic molecules, complexes, minerals, colloids, synthetic compounds) and biotic entities (microorganisms, plants, animals, humans). "Ecological thermodynamics" is a science based on equilibrium thermodynamics and non-equilibrium thermodynamics, studying the material and energy flows and their evolution within ecosystems under the framework of equilibrium and irreversible thermodynamics. It is a science that quantitatively describes the interactions between biotic and abiotic components from qualitative understanding to macroscopic thermodynamic variables. This field holds significant guiding importance for ecological construction, carbon sequestration technology, pollution control, agricultural and forestry planting, and research on global changes in marine ecology.

    "Simplicity leads to complexity in evolution." Using entropy as a starting point and classical and irreversible thermodynamics as the theoretical foundation, ecological thermodynamics derives two principles: one is the principle of minimum free energy in equilibrium thermodynamics for abiotic components, and the other is the principle of maximum energy utilization in non-equilibrium thermodynamics for biotic components. By coupling these two principles, ecological thermodynamics describes the mechanisms of interactions between biotic and abiotic components, attempting to establish an interdisciplinary science that spans inorganic-organic, abiotic-biotic, equilibrium-non-equilibrium, natural-human, and past-future interconnections. This lays the foundation for analyzing the behavioral properties and ecological evolution patterns of microorganisms, plants, animals, and humans.

    For more details, see the book "Ecological Thermodynamics" by Duan Zhenhao (expected to be published in 2026).

Close

MD/MC/EOS在地质流体系统中的应用

        通过MD/MC/Ab initio模拟和分子热力学理论研究， 我们建立热力学模型和状态方程，它们不仅在一定程度上抹平了实验数据的噪音，拟合了实验数据，使实验数据方面使用，而且外延到实验空间以外的温度-压力-成分（TPx）范围， 甚至外延到实验难以企及的条件。通过理论和实验的结合，大大增加实验数据的应用价值。

        地球内部物质可以简单地分为固体和流体， 流体是地球的“血液”，在各种地质过程中发挥重要的作用， 然而，要研究“血液”在各种地球作用过程（比如流体-岩石相互作用，成矿、温室气体全球循环、海水酸化、碳捕获与封存等的机制，必须了解其各种物理化学机制（PVTx性质，密度， 相平衡，溶解度，不混溶性、热焓、化学位等）。过去， 全世界上百个实验室的科学家们发表了近十万个有关地球流体性质的数据点， 然而这些数据基本落在几百摄氏温度和几百大气压范围内，只有少数数据达到几千或上万大气压。现有实验数据只满足于地表附近几公里内的定量研究。有些流体没有任何数据， 许多地质过程的物理化学机制无法定量研究。地质流体种类繁多，要想在短期甚至今后相当长的时间内，通过实验来研究这么多体系在不同地质条件下的各种性质是不可能的。唯一的办法是综合现代物理化学理论结合计算机模拟的办法，建立地质流体体系理论模型，综合现有的实验数据的同时，外延到更广的温度-压力-组分（TPx）范围。

        通过分子动力学（MD）模拟、从头算计算 以及开发EOS或热力学模型，我们可以不仅重现原有实验数据， 数据扩展到更广的温度-压力-组分（TPx）范围，一方面抹平了原有数据的部分误差噪音， 另一方面外延到原有数据以外的PTx范围、甚至外延到实验难以企及的条件。通过这样理和实验的结合，大大增加实验数据的应用价值。

MD/MC/EOS on geological fluid systems

    Through MD/MC/Ab initio simulations and molecular thermodynamic study, we establish thermodynamic models and equations of state. These models not only smooth out the noise in experimental data to some extent and fit the experimental data for practical use but also extend beyond the experimental space to a wider temperature-pressure-composition (TPx) range, even to conditions that are difficult to achieve experimentally. By combining theory and experiment, the application value of the experimental data is greatly increased.

    The substances inside the Earth can be simply divided into solids and fluids. Fluids are the Earth's “blood”, playing a crucial role in various geological processes. However, to study the mechanisms of how the "blood" functions, it is necessary to understand its various physicochemical properties (PVTx, density, phase equilibrium, solubility, immiscibility, thermal properties, chemical properties, etc.). Over the years, scientists from hundreds of laboratories worldwide have published nearly one hundred thousand of data points. However, these data are mostly confined to a few hundred degrees Celsius and a few hundred atmospheres, with only a small number of points reaching higher pressures. Current experimental data only satisfy quantitative research within a few kilometers near the Earth's surface in most cases. Some fluids have no data at all, making it impossible to quantitatively study the physicochemical mechanisms of many geological processes.

    The variety of geological fluids makes it impossible to study the various properties of so many systems under different geological conditions through experiments in the short term or in the foreseeable future. The only way is to combine modern physicochemical theories with computational modeling to establish theoretical models of geological fluid systems.

    Through molecular dynamics (MD) simulations, ab initio calculations, and the development of EOS or thermodynamic models, we can not only reproduce the original experimental data but also extend the data to a wider temperature-pressure-composition (TPx) range. This approach smooths out some of the error noise in the original data and extends the data beyond the original TPx range, even to conditions that are difficult to achieve experimentally. By combining theory and experiment in this way, the application value of the experimental data is greatly increased.

    We are on the way to build this site.

Close