Collaborative Research: Modeling Coupled Reactive Flow at the TAG Hydrothermal Mound

自20世纪70年代末S首次发现海底热液喷口系统以来，海底热液喷口系统一直是一个密集的研究领域，研究对象包括其流体的化学特征、在其周围生长的生物以及从海底流体中析出的矿物中生长出来的独特烟囱结构。然而，由于缺乏驱动这些系统的化学和物理过程的整体数学模型，预测海底流体流动路径以及这些系统如何在地下运行和演化的动力学仍然难以捉摸。本研究建立了高温大洋中脊海底热液系统中流体流动和反应输运的二维和三维数学模型。由此产生的模型考虑了矿物的溶解和沉淀，以及它们如何改变基底的渗透率、流体流动和流动路径。目标是检验关于是什么控制高温海底热液系统中聚焦和扩散流的分布、矿物沉淀的程度以及次表层的热/化学条件的各种假设。RST2D软件包及其修改将用于对系统进行建模。这些规则将允许进行完全耦合的反应流调查，以检查大洋中脊热液喷口系统对地壳结构、渗透率、热导率、化学分散性和其他地质变量的敏感性。这项工作的更广泛影响包括研究和教育的整合以及对计算地球科学研究生的培训。将在项目过程中创建的软件为科学建立基础设施，并具有与地热能生产和矿藏等其他领域的交叉潜力。它将通过网络向公众开放。项目的结果将通过参与的教职员工的讲座向公众展示。该项目还将支持来自科学界代表性不足的性别的PI。

From their first discovery in the late 1970's, seafloor hydrothermal vent systems have been an intensive area of study in terms of characterizing the chemistry of their fluids, the biology that thrives around them, and the unique chimney structures that grow from the minerals precipitating from the fluids coming out of the seafloor. Predicting sub-seafloor fluid flow pathways and the dynamics of how these systems operate and evolve in the subsurface, however, still remains elusive due the paucity of holistic mathematical models of the chemical and physical processes that drive these systems. This research develops 2-D and 3-D mathematical models of fluid flow and reactive transport in high temperature mid-ocean ridge seafloor hydrothermal systems. Resulting models take into account mineral dissolution and precipitation and how these change basement permeability, fluid flow, and flow pathways. Goals are to test various hypotheses about what controls the distribution of focused and diffuse flow in high temperature seafloor hydrothermal systems, the extent of mineral precipitation, and the thermal/chemical conditions in the subsurface. The RST2D software package and modifications to it will be used to model the systems. The codes will permit fully-coupled reactive-flow investigations to be carried out which can examine the sensitivity of mid-ocean ridge hydrothermal vent systems to crustal structure, permeability, thermal conductivity, chemical dispersivity, and other geologic variables. Broader impacts of the work include integration of research and education and training graduate students in computational geoscience. Software that will be created during the course of the project builds infrastructure for science and has crossover potential to other fields, such as geothermal energy production and ore deposits. It will be made publicly available over the web. Results of the project will be presented to the public via lectures by participating faculty. The project will also support a PI from a gender under-represented in the sciences.