ESR/ICP-MS dating method of the latest fault movement

首先，我们观察到使用Nojima故障500米钻孔核心样本来重置ESR信号的状态，并确认在故障gouge中ESR信号已被暂时减少。这意味着错误的样本如深，可能的是必要的，以完整地重置ESR信号。作为对故障口中ESR信号的衰减过程的计算机模拟的结果，我们应该考虑作为一种重置机制，而不仅仅是结构性的热量，但也是故障口中的Pore和crystal水的蒸发或对流.下一步，我们在500米核心样本中进行了故障口的化学分析，以确认无论是在哪里还是不实际存在的Pb。我们分析了ICP-MS 8-20微米的碎片，分别从故障罩的大块样本中分离。As a result we detected extManagement D1208 D1Pb/D1232 D1Th和D1206 D1Pb/D1238 D1U ratio anomalies from the 0- 3 mm part just on the fault plane。In the 0- 3 mm and 3- 6 mm parts of the fault gouge， the intensity of y D1206 y D1Pb/y D1238 y D1U ratio is larger than that of y D1208 y D1Pb/y D1232 y D1Th ratio， whereas in the parts of more than 6mm away from the fault plane，您的位置：知道173>> D1206> D1 Pb/> D1238> D1 U ratio is smaller than that of> D1208> D1 Pb/> D1232> D1 Th ratio。This suggests that the Pb anomaly may not be derived from the migration of the whole Pb isotopes， but from that of apart ofイD1206イD1Pb orイD1208イD1Pb。Pb异常可能被解释为Rn异常的存在，而Furthermore则通过高温和确认的半热反应在高温下的半热反应中容易产生的故障gouge。一个人可以通过ESR日期来评估错误活动，使用smectites中的固有ESR信号。在添加中，我们发现了高能粒子辐射在石英中形成一个新的ESR信号，它适用于ESR日期。

First, we inspected the resetting state of ESR signals using the Nojima Fault 500m drilling core samples, and confirmed that ESR signals in the fault gouge had been thermally reduced. This means that fault gouge samples as deep as possible are necessary for complete resetting of ESR signals. As a result of computer simulation on the decay process of ESR signals in the fault gouge, it was found that we should consider as a resetting mechanism not only frictional heat but also vaporization or convection of pore and crystal water in the fault gouge.Next, we carried out chemical analysis of the fault gouge in the 500m core samples to confirm whether or not Pb anomaly actually exists. We analyzed by ICP-MS 8-20 μ m fractions separated from the bulk samples of the fault gouge. As a result we detected extreme ィイD1208ィエD1Pb/ィイD1232ィエD1Th and ィイD1206ィエD1Pb/ィイD1238ィエD1U ratio anomalies from the 0-3mm part just on the fault plane. In the 0-3mm and 3-6mm parts of the fault gouge, the intensity of ィイD1206ィエD1Pb/ィイD1238ィエD1U ratio is larger than that of ィイD1208ィエD1Pb/ィイD1232ィエD1Th ratio, whereas in the parts of more than 6mm away from the fault plane, the intensity of ィイD1206ィエD1Pb/ィイD1238ィエD1U ratio is smaller than that of ィイD1208ィエD1Pb/ィイD1232ィエD1Th ratio. This suggests that the Pb anomaly may not be derived from the migration of the whole Pb isotopes, but from that of apart of ィイD1206ィエD1Pb or ィイD1208ィエD1Pb. The Pb anomaly may be explained by the existence of Rn anomaly.Furthermore we experimentally generated fault gouge by hyirothermal reaction at high temperature and confirmed that smectites are easily generated in natural. One can evaluate fault activity by ESR dating of fault gouge using an intrinsic ESR signal in smectites. In addition, we found by high energy particles irradiation a new ESR signal in quartz, which is applicable to ESR dating.