当前位置: X-MOL 学术Geomech. Energy Environ. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Influence of dissolution on long-term frictional properties of carbonate fault gouge
Geomechanics for Energy and the Environment ( IF 3.3 ) Pub Date : 2021-01-10 , DOI: 10.1016/j.gete.2021.100234
H. Rattez , F. Disidoro , J. Sulem , M. Veveakis

Velocity stepping experiments have been performed on a simulated calcite gouge using an annular shear apparatus to investigate the effect of dissolution on the frictional properties of a carbonate fault. The tested material was put in contact with hydrochloric acid at different concentration in order to provoke grains dissolution prior to the experiments. Particle size analysis shows that the small grains tend to disappear due to the chemical reaction, whereas the distribution of large grains is not much affected. The dissolution process induces a decrease of the fractal number of the grain size distribution and an increase of the roughness of the particles. The study of the rate-and-state parameter of the materials, which is commonly used to characterize the ability of the fault to generate earthquakes, shows a decrease towards more negative values with dissolution for dry specimens and an increase for wet samples. Moreover, a decrease of the steady state friction coefficient is observed with dissolution for wet samples. This decrease of the friction would promote the triggering of slip along an existing fault after the injection of an acid fluid like in the cases of CO2 storage or acid gas disposal projects in a carbonate reservoir, but the increase of the rate and state parameter (a–b) of saturated specimens implies that the seismogenic potential of faults could potentially be reduced.



中文翻译:

溶出度对碳酸盐岩断层泥长期摩擦性能的影响

已使用环形剪切设备在模拟方解石凿上进行了速度步进实验,以研究溶解对碳酸盐岩断层摩擦特性的影响。为了在实验前引起颗粒溶解,将被测材料与不同浓度的盐酸接触。粒度分析表明,由于化学反应,小颗粒趋于消失,而大颗粒的分布影响不大。溶解过程引起粒度分布的分形数减少和颗粒粗糙度的增加。研究材料的速率和状态参数,通常用于表征断层产生地震的能力,显示干样品的溶出度朝负值减小,而湿样品的溶出度朝负值增加。此外,对于湿样品,随着溶解,观察到稳态摩擦系数降低。摩擦的这种减小将促进在注入酸性流体后沿现有断层触发滑动,例如在CO的情况下在碳酸盐岩储层中有2个储气库或酸性气体处置项目,但是饱和标本的速率和状态参数(a–b)的增加意味着断层的潜在地震成因可能会降低。

更新日期:2021-02-10
down
wechat
bug