Collaborative Research: Serpentinization of oceanic crust: Integrated modeling of deformation, fracture, fluid flow, and heat transfer

当海底和海底的地壳与海水反应时，许多矿物从没有结构水的矿物变成了有结构水的矿物。参与海底蚀变的后一种矿物中最常见的是蛇纹石。当这种矿物形成时，岩石的体积会有很大的增加(高达40%)。由于温度和温度梯度、成分、水岩比、矿物反应、围压、断裂作用等各种参数的复杂相互作用，我们对蛇纹岩作用对大洋地壳、断裂和其他类型的大大小小形变中的裂纹扩展的影响的了解有限。这项研究通过一种综合办法处理这一问题，其中涉及发展和应用关于海底岩石中裂缝萌生和扩展的理论，并利用其结果来了解我们在海底和海底看到的构造和构造特征的形成，这些特征往往与热液喷口系统以及海底断层和变形有关。研究将使用已修订的数学模型进行，以纳入额外的基本参数和更精确的方程，以模拟裂纹的萌生和扩展。模型将被修改，以允许计算应力和应变，以确定大规模断层作用和破裂对内部和外部蛇纹状物体的重要性。模拟的结果将与亚特兰蒂斯地块、中大西洋山脊系统的一部分和日本西南的Hyuganada前弧区的观测数据进行核对。该项目的更广泛影响包括通过制作模型和建模代码为科学建设基础设施，这些模型和建模代码有可能交叉进入矿藏和能源研究领域。它还有助于提高我们利用海底和海底以下的镁铁质和超镁铁质岩石作为大气碳的可能封存地点的潜力。还包括对学生进行计算地球科学方面的培训，将研究成果纳入本科生的课堂培训，其中一名学生的性别在科学中的代表性不足。

As the crust on and under the seafloor reacts with seawater, many of the minerals get altered from those without structural H2O to those with it. The most common of the latter minerals involved in seafloor alteration is serpentine. When this mineral forms, there is a large increase in the volume of the rock (up to a 40%). Due to the complex interplay of a variety of parameters such as temperature and temperature gradients, composition, water-rock ratio, mineral reaction, confining pressure, faulting, etc. our understanding of the impact of serpentinization on crack propagation in ocean crust, faulting, and other types of deformation both small and large, is limited. This research addresses this issue through an integrated approach that involves developing and applying theories for crack initiation and propagation in seafloor rocks and using the results to understand the formation of tectonic and structural features we see on and below the seafloor, features that tend to be associated with hydrothermal vent systems and seafloor faulting and deformation. Research will be carried out using mathematical models that have been revised to incorporate additional essential parameters and more precise equations to simulate crack initiation and propagation. Models will be modified to allow calculation of stresses and strains to determine the importance of large scale faulting and fracturing on internal and external serpentinized bodies. Results of the modeling will be checked against observational data from the Atlantis Massif, part of the Mid-Atlantic Ridge system and the Hyuganada Forearc region southwest of Japan. Broader impacts of the project include building infrastructure for science by producing models and modeling codes that have the potential to crossover into the fields of ore deposit and energy research. It also helps improve our ability to tap the potential of using mafic and ultramafic rocks on and below the seafloor as possible carbon sequestration sites for atmospheric carbon. Training of students, of which one is from a gender under-represented in the sciences, in computational geoscience is also involved, as is integration of research results into classroom training for undergraduate students.