变形辅助下的岩盐流体渗透。

Deformation-assisted fluid percolation in rock salt.

机构信息

Department of Petroleum and Geosystems Engineering, The University of Texas at Austin, 200 East Dean Keeton Street, Austin, TX 78712, USA.

Department of Geological Sciences, The University of Texas at Austin, 1 University Station, Austin, TX 78712, USA. Institute for Computational Engineering and Sciences, The University of Texas at Austin, 201 East 24th Street, Austin, TX 78712, USA.

出版信息

Science. 2015 Nov 27;350(6264):1069-72. doi: 10.1126/science.aac8747.

DOI:10.1126/science.aac8747

PMID:26612949

Abstract

Deep geological storage sites for nuclear waste are commonly located in rock salt to ensure hydrological isolation from groundwater. The low permeability of static rock salt is due to a percolation threshold. However, deformation may be able to overcome this threshold and allow fluid flow. We confirm the percolation threshold in static experiments on synthetic salt samples with x-ray microtomography. We then analyze wells penetrating salt deposits in the Gulf of Mexico. The observed hydrocarbon distributions in rock salt require that percolation occurred at porosities considerably below the static threshold due to deformation-assisted percolation. Therefore, the design of nuclear waste repositories in salt should guard against deformation-driven fluid percolation. In general, static percolation thresholds may not always limit fluid flow in deforming environments.

摘要

用于核废料的深部地质储存场所通常位于岩盐中，以确保与地下水的水文隔离。静态岩盐的低渗透率是由于存在渗流阈值。然而，变形可能能够克服这个阈值并允许流体流动。我们使用 X 射线微断层扫描技术在合成盐样本的静态实验中证实了渗流阈值。然后，我们分析了墨西哥湾穿透盐矿床的井。观察到的烃类在岩盐中的分布表明，由于变形辅助渗流，在远低于静态阈值的孔隙度下发生了渗流。因此，在盐中设计核废料储存库时应防止变形驱动的流体渗流。一般来说，静态渗流阈值在变形环境中并不总是限制流体流动。