Abstract: Experimental and theoretical researches have confirmed that changes in crustal stress can be monitored by the in situ bedrock temperature. Monitoring stress by temperature requires the high-precision and multi-channel temperature measurement system. We have developed such a system, based on the several refinements. The key parameters on temperature measurement system mainly include:1)the accuracy is better than 1.0mK. At the 99.5%confidence level, the accuracy reaches 0.5mK. This system can be used to detect the change of magnitude of a few tenths to several MPa. The sampling period can be set, depending on remote control. The sampling period is usually set 5 or 15 minutes. 2)A system has up to 20 channels, and commonly uses for 8 or 12 channels. 3)This system has a significant performance in low power consumption. The power is supplied by lead-acid battery with 12 volt. It is at least 2 years that a lead-acid battery, with contents of 120Ah12V, can supply the power for a system with 8 channels. In conclusion, multichannel temperature measurement system with high precision and low power consumption is designed and realized. Specially, the performance in low power consumption is of great significance, which can greatly reduce the maintenance cost after the measurement station is constructed. This temperature measurement system provides a basic technology for monitoring changes in crustal stress with bedrock temperature.

Key words: stress measurement, temperature measurement system, multichannel, high precision, low power consumption

摘要： 近年来的实验和野外观测证实可通过基岩温度测量来获得地壳应力状态变化，称为"热测应力"。高精度的温度观测系统是"热测应力"的关键技术。经过多年研制，前后经历了多期修改，目前已较完善。核心技术指标包括：1）温度测量系统的精度优于1.0mK；在99.5%的置信水平上，精度达到了0.5mK。相当于可以测量到几个或零点几个MPa量级的地壳应力变化。其中，采样周期远程可调，实际中采样周期通常设为5min，或15min。2）通道数：单台可达20个通道。目前常用8或12通道。3）实现低功耗：采用铅酸电池供电，120Ah12V铅酸电池，对于8个通道深度为20m的地温观测台，可连续供电≥2a。总之，高精度多通道低功耗温度测量系统的研发成功，尤其低功耗设计的实际效果显著，极大地降低了后期维护成本。这对于利用基岩温度观测地壳应力变化提供了1个良好的技术基础。

关键词: 应力测量, 温度测量, 高精度, 多路测量, 低功耗