Seismic waves from a magnitude 8.3 earthquake in Japan were consistently recorded by five nearly identical gPhone gravity meters in Colorado. Good correlation was also found in the response of two different types of g...Seismic waves from a magnitude 8.3 earthquake in Japan were consistently recorded by five nearly identical gPhone gravity meters in Colorado. Good correlation was also found in the response of two different types of gravity meters and a standard seismometer in Walferdange, Luxembourg to an earthquake of magnitude 8.2 in Japan, indicating that all of them were capable of measuring the surface waves reliably. The gravity meters, however, recorded 11 separate arrivals of Raleigh waves, while the seismometer only one. Thus the gravity meters may be useful for obtaining new information in the study of seismic velocities, attenuation and dispersion.展开更多
Kick and loss are two complicated incidents that affect the construction safety in oil and gas well drilling.The commonly-used kick/loss monitoring methods are disadvantageous with monitoring lag and low metering prec...Kick and loss are two complicated incidents that affect the construction safety in oil and gas well drilling.The commonly-used kick/loss monitoring methods are disadvantageous with monitoring lag and low metering precision,which may cause well collapse,pipe sticking and well blowouts due to untimely detection and improper treatment.In this paper,a new type of kick/loss monitoring and metering system was designed based upon a comparative analysis of several kick/loss monitoring methods commonly used on rig sites.This new system has the functions of early monitoring and alarm,kick/loss velocity metering,total loss metering and automatic filling,and its feasibility was verified through laboratory experiments.And the following research results were obtained.First,the monitoring tank of this new system is divided into two chambers,i.e.,a main chamber and a secondary chamber.The return of drilling fluid partially flows back to the shale shaker through the main chamber,and the rest overflows into the secondary chamber.Second,the internal cross section area of the secondary chamber is small,which increases the response sensitivity to liquid level change,so kick/loss can be detected in time.Third,the water head of the outlet pipeline of the main chamber remains constant and the outlet flow is stable,so kick/loss velocity and total kick/loss can be calculated quantitatively based on the change of liquid level in the secondary chamber.And the monitoring error of kick/loss velocity is less than 8%.Fourth,in the process of tripping out,the drilling fluid in the monitoring tank flows into the wellbore under the action of self weight to keep the full liquid level of the wellbore all the time.As a result,lagged filling and partial filling are eliminated.In conclusion,this new kick/loss monitoring system is economical and practical,and giving a full play to the advantages of ground survey and alarm timely and accurately.展开更多
This study presents the results of the preliminary tests performed using a kerma-area product (KAP) meter in order to verify its usefulness as a monitor chamber in a clinical X ray system, which will be used in ioniza...This study presents the results of the preliminary tests performed using a kerma-area product (KAP) meter in order to verify its usefulness as a monitor chamber in a clinical X ray system, which will be used in ionization chambers’ quality control program. The tests performed were repeatability, surface measurement uniformity, linearity with tube current, measurement variation changing the distance and field size, KAP chamber radiation attenuation, and energy dependence. The KAP meter has presented a good repeatability (a maximum variation of 0.4%);its surface has a homogeneous response (a maximum variation of 1.0% among the different irradiated regions);the response is linear with the tube current and the variation of the PKA along the distance is less than 3.43%. On the other hand, the results obtained for chamber attenuation and energy dependence show that some corrections must be applied when the measurements are made. The results have shown a good performance of the KAP meter, confirming that it is possible to use this instrument as a monitor chamber. However, it is important to highlight that some correction factors for energy dependence and chamber radiation attenuation must be considered.展开更多
The Kunlunshan Mountain Ms8.1 earthquake, occurred in Nov.14, 2001, is the first event with magnitude more than 8 in the China earthquake monitoring history, specifically at the beginning of digital techniques in prec...The Kunlunshan Mountain Ms8.1 earthquake, occurred in Nov.14, 2001, is the first event with magnitude more than 8 in the China earthquake monitoring history, specifically at the beginning of digital techniques in precursor monitoring networks. Any investigation of recorded data on this earthquake is very important for testing the operation of the digital monitoring networks and understanding the preparation, occurrence, and adjustment of stress/strain of strong continental earthquakes. In this paper we investigated the coseismic response changes of well water level of groundwater and volume strain meter of bore hole in digital earthquake monitoring network of Capital area and its vicinity, due to the Nov.14, 2001 Ms8.1 Kunlun Mountain earthquake. The responding time, shapes or manners, amplitudes, and lasting time of well water level and strain-meters to seismic wave are studied in comparison. Then we discussed the possibility that the response changes of groundwater to strong distant earthquakes can be understood as one kind of observing evidence of stress/strain changes induced by distant earthquake.展开更多
Aiming at the limitation of traditional measuring soil water potential, the paper presents an information system based GSM to real-time monitor data coming from multiple data sources. The monitoring system, which cons...Aiming at the limitation of traditional measuring soil water potential, the paper presents an information system based GSM to real-time monitor data coming from multiple data sources. The monitoring system, which consisted of monitoring center, GSM transmission channel and data detection terminal, was given. The detection terminal included the measuring station and TS-2 negative pressure meter, which was applied to measure soil water potential. Nowadays the system has been successfully applied to drip irrigation in the cotton field on farm in Xinjiang region. The system provides a feasible technology frame-work for collecting and processing wide geographical distribution data in farmland.展开更多
文摘Seismic waves from a magnitude 8.3 earthquake in Japan were consistently recorded by five nearly identical gPhone gravity meters in Colorado. Good correlation was also found in the response of two different types of gravity meters and a standard seismometer in Walferdange, Luxembourg to an earthquake of magnitude 8.2 in Japan, indicating that all of them were capable of measuring the surface waves reliably. The gravity meters, however, recorded 11 separate arrivals of Raleigh waves, while the seismometer only one. Thus the gravity meters may be useful for obtaining new information in the study of seismic velocities, attenuation and dispersion.
基金supported by the National Major Science and Technology Project"Drilling and Completion Technology for Efficient Development of Low Permeability Oil and Gas Reservoirs-Key Tools and Equipment for Drilling Speed Enhancement and Efficiency Improvement in Complex Formations"(No.:2016ZX05021-003).
文摘Kick and loss are two complicated incidents that affect the construction safety in oil and gas well drilling.The commonly-used kick/loss monitoring methods are disadvantageous with monitoring lag and low metering precision,which may cause well collapse,pipe sticking and well blowouts due to untimely detection and improper treatment.In this paper,a new type of kick/loss monitoring and metering system was designed based upon a comparative analysis of several kick/loss monitoring methods commonly used on rig sites.This new system has the functions of early monitoring and alarm,kick/loss velocity metering,total loss metering and automatic filling,and its feasibility was verified through laboratory experiments.And the following research results were obtained.First,the monitoring tank of this new system is divided into two chambers,i.e.,a main chamber and a secondary chamber.The return of drilling fluid partially flows back to the shale shaker through the main chamber,and the rest overflows into the secondary chamber.Second,the internal cross section area of the secondary chamber is small,which increases the response sensitivity to liquid level change,so kick/loss can be detected in time.Third,the water head of the outlet pipeline of the main chamber remains constant and the outlet flow is stable,so kick/loss velocity and total kick/loss can be calculated quantitatively based on the change of liquid level in the secondary chamber.And the monitoring error of kick/loss velocity is less than 8%.Fourth,in the process of tripping out,the drilling fluid in the monitoring tank flows into the wellbore under the action of self weight to keep the full liquid level of the wellbore all the time.As a result,lagged filling and partial filling are eliminated.In conclusion,this new kick/loss monitoring system is economical and practical,and giving a full play to the advantages of ground survey and alarm timely and accurately.
文摘This study presents the results of the preliminary tests performed using a kerma-area product (KAP) meter in order to verify its usefulness as a monitor chamber in a clinical X ray system, which will be used in ionization chambers’ quality control program. The tests performed were repeatability, surface measurement uniformity, linearity with tube current, measurement variation changing the distance and field size, KAP chamber radiation attenuation, and energy dependence. The KAP meter has presented a good repeatability (a maximum variation of 0.4%);its surface has a homogeneous response (a maximum variation of 1.0% among the different irradiated regions);the response is linear with the tube current and the variation of the PKA along the distance is less than 3.43%. On the other hand, the results obtained for chamber attenuation and energy dependence show that some corrections must be applied when the measurements are made. The results have shown a good performance of the KAP meter, confirming that it is possible to use this instrument as a monitor chamber. However, it is important to highlight that some correction factors for energy dependence and chamber radiation attenuation must be considered.
基金supported by Natural Science Foundation of China(41274061 and 40374019)
文摘The Kunlunshan Mountain Ms8.1 earthquake, occurred in Nov.14, 2001, is the first event with magnitude more than 8 in the China earthquake monitoring history, specifically at the beginning of digital techniques in precursor monitoring networks. Any investigation of recorded data on this earthquake is very important for testing the operation of the digital monitoring networks and understanding the preparation, occurrence, and adjustment of stress/strain of strong continental earthquakes. In this paper we investigated the coseismic response changes of well water level of groundwater and volume strain meter of bore hole in digital earthquake monitoring network of Capital area and its vicinity, due to the Nov.14, 2001 Ms8.1 Kunlun Mountain earthquake. The responding time, shapes or manners, amplitudes, and lasting time of well water level and strain-meters to seismic wave are studied in comparison. Then we discussed the possibility that the response changes of groundwater to strong distant earthquakes can be understood as one kind of observing evidence of stress/strain changes induced by distant earthquake.
文摘Aiming at the limitation of traditional measuring soil water potential, the paper presents an information system based GSM to real-time monitor data coming from multiple data sources. The monitoring system, which consisted of monitoring center, GSM transmission channel and data detection terminal, was given. The detection terminal included the measuring station and TS-2 negative pressure meter, which was applied to measure soil water potential. Nowadays the system has been successfully applied to drip irrigation in the cotton field on farm in Xinjiang region. The system provides a feasible technology frame-work for collecting and processing wide geographical distribution data in farmland.
