Farecast of Seismic Activity in the North Aratolian fault

土耳其北部的北安那托利亚断裂带被认为是地震预测研究的试验场，因为那里存在所谓的地震间隙。本研究的目的是通过地震研究来研究地震发生的特征，以及它们与未来被认为发生在断裂带的大地震的关系。此外，还对断裂带地磁场和大地磁场进行了连续测量，以发现异常并阐明其机制。(1)地震观测为监测断裂带微震活动，我们建立了由1个基站和5个卫星站组成的无线电连接地震观测系统，其中基站设置了3分量地震仪，卫星站设置了1个垂直分量地震仪。从观测中发现，在断裂带已经发生了一些微震，但对断裂带的微震活动的探测水平仍然不足。所以我们现在正在安装更多的站点。(2)应变测量在间隙区离活动断层很近的一个监测站安装了精密应变仪，监测断层位移可能引起的应变变化。然而，由于安装深度太浅，无法摆脱温度效应，因此必须对观测数据进行处理，以消除这种影响。(3)地磁和大地测量7个地磁站和2个大地测量站已投入运行，监测研究区与地震有关的地磁场和大地磁场可能发生的变化。到目前为止，我们已经获得了一些与一些相当小的地震有关的大地磁场异常变化的例子。(4)震源过程研究我们分析了土耳其20多个地震事件的地震记录，明确了与构造有关的详细震源过程。特别是发现1967年穆杜尔努河谷地震具有复杂的震源过程，该地震总体上可以用走滑机制来表征，但在其西端发现了正断层成分。这有望为研究穆杜尔努河谷震源区以西的断陷区大地震的发生过程提供线索。少

The North Anatolian fault zone in northern Turkey has been considered to be a test field for earthquake prediction studies, because there exists a so-called seismic gap. The purpose of this research is to investigate the characteristics of earthquake generation through seismic studies and their relation to a large earthquake which has been considered to occur in the gap area in the future. In addition, continuous measurements of the geomagnetic and telluric fields have been made in the gap area to detect anomalies and clarify their mechanisms.(1) Seismic observationIn order to monitor microseismic activity in the gap area, we have established a radio-linked seismic observation system consisting of a base station, where a three-component seismometer was set up, and five saztellite stations, where a vertical-component seismometer was installed. It was found from the observations that some microearthquakes have been occurring in the gap area, but the detection level for microseismicity tu … More rned out to be still insufficient. So we are now installing a few more stations.(2) Strain measurementA precise strainmeter was installed at a station located very close to an active fault in the gap area to monitor a possible strain change associated with fault displacement. However, the installation depth turned out to be too shallow to escape from the temperature effect and the observed data must be processed so as to remove this effect.(3) Geomasgnetic and telluric measurementsSeven geomagnetic and two telluric stations have been in operation to monitor possible changes in the geomagnetic and telluric fields associated with earth quakes in the study area. So far we have obtained some examples of anomalous changes in the telluric field associated with some rather small earthquakes.(4) Study of earthquake source processWe have analyzed seismic records of more than twenty events in Turkey, and detailed earthquake source processes have benn clarified in relation to tectonics. In particular, it was found that the 1967 Mudurnu Valley easrthquake has a complicated source process, this earthquake can be characterized generally by a strike-slip mechanism, but at its western end the normal-fault constituent was found. This is expected to provide a clue to the generation process of a large earthquake in the gap area, that is the west of the source area of the Mudurnu Valley earthquake. Less