Evolution of mine caves in soluble rocks driven by deep-seated settings

深部环境驱动的可溶性岩石矿洞的演化

• 批准号: 510737201
• 负责人: Professor Dr. Georg Kaufmann
• 金额: --
• 依托单位: Fachrichtung Geophysik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/510737201?language=en
• 关键词: Evolution; mine; caves; soluble; rocks

Permeability in soluble rocks increases significantly with time. While the primary permeability is controlled by the initial pore and fracture space, the fluid circulating through soluble rocks can remove material from pore and fracture surfaces, increasing the interconnected void space in the rock and thus creating a secondary permeability, often orders of magnitude larger than the primary permeability. When the mass transfer in soluble rocks creates focused flow through enlarged conduits, we often refer to the system as karst. The enlargement of fractures and pore spaces is called speleogenesis. The temporal evolution of karst is driven by flow. Depending on the origin of the fluid, we distinguish epigenetic and hypogenetic karst evolution, the former with flow from above the soluble rock formation, the latter with flow from below. While epigenetic karst evolution is well understood and dominates the literature, hypogenetic karst evolution is more elusive. The reason is often the restricted accessibility of karst structures developed under hypogene settings. We propose to develop numerical models, coupling flow, transport and reaction, which describe the temporal evolution of a species type of caves, mine caves, discovered by mining and often developed under hypogenetic conditions. We use a variety of locations (from Germany) to derive a setup and appropriate boundary conditions. Focusing on two different aspects, the chemistry and the flow in mine-cave settings, we want to learn about the processes leading to mine-cave formation in a quantitative way.

可溶岩的渗透率随着时间的延长而显著增加。虽然原始渗透率受初始孔隙和裂缝空间的控制，但在可溶岩石中循环的流体可以从孔隙和裂缝表面去除物质，增加岩石中相互关联的孔隙空间，从而产生二次渗透率，通常比原始渗透率大几个数量级。当可溶岩中的质量传递通过扩大的管道产生聚焦流时，我们通常将该系统称为岩溶。裂缝和孔隙空间的扩大称为洞穴形成。岩溶的时间演化受水流的驱动。根据流体的来源，我们区分了后生岩溶演化和后生岩溶演化，前者是从可溶岩层上方流来的，后者是从下面流来的。虽然表生岩溶演化已被很好地理解并在文献中占据主导地位，但低生岩溶演化更是难以捉摸。其原因往往是在低生环境下形成的岩溶结构的可达性受到限制。我们建议开发数值模型，耦合流动、传输和反应，描述一种物种类型的洞穴的时间演化，矿山洞穴是通过采矿发现的，通常是在欠生成条件下发育的。我们使用不同的位置(来自德国)来推导设置和适当的边界条件。聚焦于两个不同的方面，化学和矿洞环境中的流动，我们想要定量地了解导致矿洞形成的过程。