This study presents a plan for seismic monitoring of a region around a potential nuclear power plant. Seismic monitoring is needed to evaluate seismic risk. The International Atomic Energy Agency has set guidelines on seismic hazard evaluation and monitoring of such areas. According to these guidelines, we have made a plan for a local network of seismic stations to collect data for seismic source characterization and seismotectonic interpretations, as well as to monitor seismic activity and natural hazards. The detection and location capability of the network were simulated using different station configurations by computing spatial azimuthal coverages and detection threshold magnitudes. Background noise conditions around Pyhäjoki were analyzed by comparing data from different stations. The annual number of microearthquakes that should be detected with a dense local network centered around Pyhäjoki was estimated. The network should be dense enough to fulfill the requirements of azimuthal coverage better than 180° and automatic event location capability down to ML ∼ 0 within a distance of 25 km from the site. A network of 10 stations should be enough to reach these goals. With this setup, the detection threshold magnitudes are estimated to be ML = −0.1 and ML = 0.1 within a radius of 25 and 50 km from Pyhäjoki, respectively. The annual number of earthquakes detected by the network is estimated to be 2 (ML ≥ ∼ −0.1) within 25 km radius and 5 (ML ≥ ∼−0.1 to ∼0.1) within 50 km radius. The location accuracy within 25 km radius is estimated to be 1–2 and 4 km for horizontal coordinates and depth, respectively. Thus, the network is dense enough to map out capable faults with horizontal accuracy of 1–2 km within 25 km radius of the site. The estimation is based on the location accuracies of five existing networks in northern Europe. Local factors, such as seismic noise sources, geology and infrastructure might limit the station configuration and detection and location capability of the network.

中文翻译：

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用于监视潜在核电站区域的本地地震网络。

这项研究提出了对潜在核电厂周围地区进行地震监测的计划。需要地震监测以评估地震风险。国际原子能机构已经制定了有关地震危险性评估和此类区域监测的准则。根据这些准则，我们已制定了一个计划，以建立一个地震台地局域网，以收集用于地震震源特征和地震构造解释的数据，以及监测地震活动和自然灾害。通过计算空间方位角覆盖范围和检测阈值幅度，使用不同的站配置来模拟网络的检测和定位能力。通过比较不同气象站的数据，分析了皮哈约基附近的背景噪声状况。估计应该以皮哈约基（Pyhäjoki）为中心的密集本地网络检测到的微地震的年数量。网络应足够密集，以在距站点25 km的距离内满足优于180°的方位角覆盖范围和低至ML〜0的自动事件定位能力的要求。一个由10个站点组成的网络应足以实现这些目标。通过这种设置，在距比哈霍基（Pyhäjoki）25公里和50公里的半径内，检测阈值的大小分别估计为ML = -0.1和ML = 0.1。该网络检测到的年地震次数估计在25 km半径内为2（ML≥〜-0.1），在50 km半径内为5（ML≥-0.1至〜0.1）。对于水平坐标和深度，在25 km半径内的定位精度估计分别为1-2和4 km。因此，网络的密度足够大，可以在站点半径25 km之内以1–2 km的水平精度绘制出能胜任的断层。该估计基于北欧五个现有网络的位置精度。诸如地震噪声源，地质和基础设施之类的本地因素可能会限制站点的配置以及网络的检测和定位能力。