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于1997年南方的夏季,在南极洲毛德皇后地西部的德国诺伊迈尔基地附近布设了一个小孔径地震台阵。小孔径台阵是监测和定位地方或区域范围内微震的重要的地震学手段。地震台阵记录优于单台记录,可以直接计算地震信号的慢度矢量。另一个优点是通过各道聚束或叠加来提高信噪比。这个台阵由15个短周期垂直向地震计组成,布设成三个同心圆,最大孔径为2km,中心地震计是三分量宽频带地震计。这个台阵沿用了现有北半球台阵的设计,如挪威的NORESS和ARCESS台阵。同时在南非新萨纳四号基地布设了一个标准宽频带地震台站(台站代号为SNAA)。1998年初,在阿根廷贝尔格拉诺二号基地(BELO)布设了另外一个地震台站,SNAA和BELO台站拓展了诺伊迈尔地震台阵的孔径,使其达到1100 km。该台阵建立以来,已检测到一些发生在毛德皇后地被动陆缘的地方地震。检测到这些事件说明了该台阵具有很好的监测能力并且有助于更好地了解该地区的地质构造演化。更有意义的是,现在可以检测到南桑威奇地区的地震事件,并且定位精度也大大提高。而此前在这个地区观测到的许多地震事件在全球目录中都不曾出现。
In the summer of 1997 in the south, a small-aperture seismic array was laid near the Neumarkt base in Germany’s western part of the Maw Queen in Antarctica. Small aperture arrays are important seismological means of monitoring and locating microseisms at local or regional scales. Seismic array records better than a single record, you can directly calculate the slowness vector of seismic signals. Another advantage is improved signal-to-noise ratio by beam bunching or stacking. The array consists of 15 short-period vertical seismometers, arranged in three concentric circles with a maximum aperture of 2 km and a center seismometer as a three-component broadband seismometer. This array follows the design of the existing Northern Hemisphere array, such as Norway’s NORESS and ARCESS array. At the same time, a standard broadband seismic station (station codenamed SNAA) was deployed at New Sanaa Base 4 in South Africa. In early 1998, another seismic station was deployed at BELO in Argentina, and the SNAA and BELO stations expanded the aperture of Neumaier seismic array to 1,100 km. Since the establishment of the array, some earthquakes that occurred in the maldives’ passive margins have been detected. The detection of these events shows that the array has good monitoring capabilities and helps to better understand the evolution of the geological structure in the area. More significantly, the seismic event in South Sandwich can now be detected and the positioning accuracy dramatically increased. Many of the earthquakes that have been observed in the area before have not appeared in the global catalog.