Frictional healing of quartz gouge under hydrothermal conditions: 1. Experimental evidence for solution transfer healing mechanism
Frictional healing of quartz gouge under hydrothermal conditions: 1. Experimental evidence for solution transfer healing mechanism
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DOI：
10.1029/2001jb001522
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发表时间：
2004-07-10
影响因子：
3.9
通讯作者：
Scholz, CH
中科院分区：
文献类型：
--
作者：
Nakatani, M;Scholz, CH
热液条件下石英泥的摩擦特性实验揭示了一种新的断层愈合机制，该机制仅在液相水存在的高温下运行。这与众所周知的“dieterich型”愈合不同，后者也在室温下进行，只取决于水的化学活性，而不取决于其相。液态水存在的要求是诊断某种形式的溶液转移是潜在的过程。此外，当孔隙水与二氧化硅处于化学平衡时，新的修复机制就会起作用，这表明溶液转移只需要局部的质量再分配，比如压力溶液。这种新的溶液转移愈合机制具有与dieterich型愈合相同的对数形式，δ (mu)=b ln (t（h)/t(c)+1）。其b值为0.010 ~ 0.014，在100 ~ 200℃范围内无明显的温度依赖性，其幅度与dieterich型愈合相差不大。它的特点是截止时间t(c)，比dieterich型机制大好几个数量级。该参数随温度呈指数递减，表明表观活化能为54 kJ/mol。该机制也具有类似于500 μ m的临界滑移距离，远远大于10 μ m的典型dieterich型愈合。通过对速度阶跃和滑动-保持-滑动试验中溶液转移愈合表现的比较，表明该机制符合速率-状态摩擦规律，但其不同的参数值可能对地震物理有新的启示。
Experiments on the frictional properties of quartz gouge under hydrothermal conditions have revealed a new fault healing mechanism that operates only at elevated temperature in the presence of liquid-phase water. This distinguishes it from the well-known "Dieterich-type'' healing that also operates at room temperature and depends only on the chemical activity of water and not on its phase. The requirement for liquid water to be present is diagnostic of some form of solution transfer being the underlying process. Furthermore, the new healing mechanism operates when the aqueous pore fluid is in chemical equilibrium with silica, indicating solution transfer with only local mass redistribution, such as pressure solution. This new solution transfer healing mechanism has the same logarithmic form, Delta(mu)=b ln (t(h)/t(c)+1), as Dieterich-type healing. Its b value was 0.010-0.014, with no clear temperature dependence in the range 100-200degreesC, and its magnitude is not very different from that of Dieterich-type healing. It is distinguished by a cutoff time, t(c), many orders of magnitude greater than the Dieterich-type mechanism. This parameter decreases exponentially with temperature, indicating an apparent activation energy of 54 kJ/mol. This mechanism also has a critical slip distance similar to500 mum, much greater than the 10 mum typical of Dieterich-type healing. Comparison of the manifestations of this solution transfer healing in velocity step and slide-hold-slide tests indicates that this mechanism is compatible with the rate-state friction law, but its different parameter values may have new implications for earthquake physics.