Fault Line Selection Method Considering Grounding Fault Angle for Distribution Network

In the distribution network system with its neutral point grounding via arc suppression coil, when single-phase grounding fault occurred near zero-crossing point of the phase voltage, the inaccuracy of the line selection always existed in existing methods. According to the characteristics that transient current was different between the fault feeder and other faultless feeders, wavelet transformation was performed on data of the transient current within a power frequency cycle after the fault occurred. Based on different fault angles, wavelet energy in corresponding frequency band was chosen to compare. The result was that wavelet energy in fault feeder was the largest of all, and it was larger than sum of those in other faultless feeders, when the bus broke down, the disparity between each wavelet energy was not significant. Fault line could be selected out by the criterion above. The results of MATLAB/simulink simulation experiment indicated that this method had anti-interference capacity and was feasible.

Effect of soil cohesion and friction angles on reverse faults

Severe faults have caused many earthquakes around the world throughout history.More recently,earthquakes have occurred in Taiwan,China(Chi-Chi fault),and elsewhere,causing loss of lives and destroying many buildings and structures.These tectonic movements have gained attention from engineers,and in the past 15 years,the focus has been on faulting mechanisms.In this study,a physical model(1 g)was fabricated and used to evaluate the impact of a reverse fault in a field with a tunnel.In the 1 g model,researchers installed additional gauges on the tunnel,so that all the displacements could be adjusted,and all the responses could be monitored during faulting.An experimental study of various soil properties(cohesion and friction angles)in reverse faults on the tunnel lining were carried out and are described herein.A comparison of results for different levels of soil cohesion revealed that it can dramatically reduce the displacement by as much as 40%,and that friction angles of 27ºcan record approximately 60%more displacements than at 37º.Furthermore,a comparison of fault angles of 30ºand 60ºindicates that the displacements can be different by more than 43%in cohesionless soil and about 64%for a friction angle of 27º.

Study on crust-mantle tectonics and its velocity structure along the Beijing-Huailai-Fengzhen profile

In order to investigate the interrelations of crust and upper mantle tectonics and its velocity distribution as well as seismicity in the Yanhuai basin and its surrounding area, a nearly EW trending Beijing Huailai Fengzhen wide angle reflection/refraction profile, which obliquely passes through seismic zone of Zhangjiakou Bohai Sea and coincides with a deep reflection profile in the Yanhuai basin, was completed recently. The results show: The crust presents layered structures and its thickness gradually increases from 35.0 km in Shunyi to 42.0 km in the west end of the profile; the interior crustal interfaces appear approximately horizontal or slowly sloping down from east to west; In the Yanhuai basin, the crust presents the characteristics of higher velocities alternating with the lower ones and the low velocity bodies obviously exist in the lower part of upper crust. Moreover, there are two deep crustal fault zones which stretch to the Moho discontinuity, are closely related with the seismicity in the Yanhuai area.

Comparative New Insight into the Tectonic Origin of Folds and Thrust Faults of an Extensional Basin: Soke-Kusadasi Basin, Aegean, Western Turkey

The Aegean area of the western Anatolian region of Turkey,controlled by the low-angle detachment normal fault system,forms an extensional province,the West Anatolian Extensional Province(WAEP).The tectonic deformation which occurred in the Miocene Period,including the Plio–Quaternary Period has created different structures in both the basement rocks and intra-basin deposits of the crust.One of these structures,high-angle normal faults,controls the supradetachment Soke-Kusadasi Basin(SKB).Within this basin,there are folds with different axes and thrust faults with a north-northwestnortheast(N,NW,NE)trend.These folds and thrust faults in the SKB deformed the sedimentary structures of intra-basin deposits.The folds and thrust faults,which caused the rotation of beddings and imbrications in the SKB,are mainly associated with the tectonic process of the low angle detachment normal fault,which affected the SKB and the Aegean part of western Anatolia.In the SKB,during the process of extensional deformation associated with primary low angle detachment normal faulting,the ramp-flat and inversion geometry observed in the basement rocks and basin deposits of the crust caused folds and thrust faults in only intra-basin deposits.In the WAEP,it is determined for the first time that the folds and thrust faults causing limited shortening deformed the Plio–Quaternary sediments.