... characterisation of the EDZ. The P-wave tomography covered a three-dimensional volume of the EDZ field sampled by multiple two-dimensional planes defined by drillholes, providing 30 2-D sections along the North-South, East-West, North West-South East and North East-South West directions. A total of 24 sensors were...

... principle, transducer structure, tech- nical specifications, install method, data acquisition and network communication technique are introduced. In addition, its observation location and earthquake precursor application in china are also described. 2 TRANSDUCER STRUCTURE OF TJ-2 China s TJ2 sensor...

... Method (CBDM). In this paper, the theory of the CBDM is described, as well as the prototype instrument with the laser displacement sensor. Analyzing influence factors on measurement result theoretically, it makes clear that stress change within rock mass can be estimated by the CBDM. 1 INTRODUCTION...

... ABSTRACT: A new instrument of 3-component volume borehole strainmeter is developed in China and the primarily function is for borehole strain measurement. The sensor is designed on the base of type TJ-2 volume borehole strainmeter, and it has three independent components which make it being...

... inversion. Japanese scholars exerted vertical strain measurements, which were used to achieve three-dimensional strain observation together with horizontal strain measurements. However, its magnetic sensor prevent them from having large dynamic range of measurement and high sensitivity. Large magnetic drift...

... ABSTRACT: In this paper, the design of strain measuring sensor technology of geophysical comprehensive observations in deep boreholes, the measurement principles of the capacitive displacement sensor are generally introduced. And the sensor adjustment technology is described in details. Signal...

... Earthquake continuous monitoring sensor Reservoir Characterization strainmeter multi-component borehole instrument strain sensor Upstream Oil & Gas type borehole strainmeter instrument borehole strainmeter deep borehole nanostrain deformation data rate borehole zhangzhou station crustal...

... sensors are hard to meet the monitoring requirements of high sensitivity and long lifetime. For a better observation of the earthquake precursor, a high sensitive fiber Bragg grating (FBG) temperature sensor is designed to monitoring a well at 87. 5±1°C. The performance of the FBG sensor demonstrates...