U.S. Geological Survey, Denver Federal Center, MS964, Denver, CO 80225, USA.
Ground Water. 2011 Mar-Apr;49(2):250-69. doi: 10.1111/j.1745-6584.2010.00676.x.
Hydrogeophysical methods are presented that support the siting and monitoring of aquifer storage and recovery (ASR) systems. These methods are presented as numerical simulations in the context of a proposed ASR experiment in Kuwait, although the techniques are applicable to numerous ASR projects. Bulk geophysical properties are calculated directly from ASR flow and solute transport simulations using standard petrophysical relationships and are used to simulate the dynamic geophysical response to ASR. This strategy provides a quantitative framework for determining site-specific geophysical methods and data acquisition geometries that can provide the most useful information about the ASR implementation. An axisymmetric, coupled fluid flow and solute transport model simulates injection, storage, and withdrawal of fresh water (salinity ∼500 ppm) into the Dammam aquifer, a tertiary carbonate formation with native salinity approximately 6000 ppm. Sensitivity of the flow simulations to the correlation length of aquifer heterogeneity, aquifer dispersivity, and hydraulic permeability of the confining layer are investigated. The geophysical response using electrical resistivity, time-domain electromagnetic (TEM), and seismic methods is computed at regular intervals during the ASR simulation to investigate the sensitivity of these different techniques to changes in subsurface properties. For the electrical and electromagnetic methods, fluid electric conductivity is derived from the modeled salinity and is combined with an assumed porosity model to compute a bulk electrical resistivity structure. The seismic response is computed from the porosity model and changes in effective stress due to fluid pressure variations during injection/recovery, while changes in fluid properties are introduced through Gassmann fluid substitution.
提出了一些水文地球物理方法，用于支持含水层储存和恢复（ASR）系统的选址和监测。这些方法以科威特拟议的 ASR 实验为背景进行数值模拟，尽管这些技术适用于许多 ASR 项目。通过使用标准的岩石物理关系，从 ASR 流动和溶质运移模拟中直接计算出整体地球物理性质，并用于模拟 ASR 对动态地球物理的响应。该策略为确定特定于场地的地球物理方法和数据采集几何形状提供了定量框架，这些方法和数据采集几何形状可以提供有关 ASR 实施的最有用信息。一个轴对称、流体流动和溶质运移耦合模型模拟了淡水（盐度约为 500ppm）注入、储存和回采到达曼含水层的过程，该含水层是一个原生盐度约为 6000ppm 的三级碳酸盐地层。调查了含水层非均质性相关长度、含水层弥散度和隔水层水力渗透率对流动模拟的敏感性。在 ASR 模拟过程中定期计算电阻率、时域电磁（TEM）和地震方法的地球物理响应，以研究这些不同技术对地下特性变化的敏感性。对于电和电磁方法，从模型化的盐度中推导出流体电导率，并与假设的孔隙率模型相结合，以计算整体电阻率结构。地震响应是从孔隙率模型和由于注入/回收过程中流体压力变化引起的有效应力变化计算得出的，而流体性质的变化则通过 Gassmann 流体替代引入。
