Collaborative Research: Mining Seismic Wavefields

南加州地震中心(SCEC)的一个工作组将通过数据密集型计算技术开发和部署挖掘地震波场的网络基础设施，以便将地震检测的相似性搜索扩展到海量数据集。相似搜索已被用来理解构造震动的机制，改变我们对断层活动深度相关性的理解，阐明余震活动中的扩散，并揭示诱发地震的新见解。这些结果是在适度的数据量下实现的吗？从横跨约10公里的~10个地震台？然而，他们将探测到的地震数量增加了10倍至100倍。这个地理信息学项目将开发所需的网络基础设施，通过在海量数据中发现以前未检测到的地震事件来实现对地震过程的高灵敏度研究。该项目的目标是开发一个挖掘地震波形数据的网络基础设施。这项工作将开发方法和硬件，在非常大的波形数据库上使用相干信号处理，以检测、定位和表征标准网络操作无法检测到的事件(单次到达检测、关联、优化定位)。该方法涉及使用基于网络的方法进行地震检测，特别是在目前单独处理信号的方法中没有报告的微弱和不寻常的事件。PI将解决大T和大N问题，其中大T是使用多个事件随时间的波形相似性来检测长时间段的地震；大N是使用在具有多达数千个台站的密集地震阵列上记录的空间上单个事件的波形相似性。结果将极大地增加对各种类型震源数量的了解，并可能识别地震发生的模式，从而为灾害和短期破裂预测提供信息。人类活动引发的地震活动是一个新出现的问题，对21世纪的能源选择产生了不利影响，包括页岩气开发、增强的地热能和碳封存。更全面地了解与这些活动相关的地震活动，对于管理它们构成的风险至关重要。

A working group of the Southern California Earthquake Center (SCEC) will develop and deploy cyberinfrastructure for mining seismic wavefields through data intensive computing techniques in order to extend similarity search for earthquake detection to massive data sets. Similarity search has been used to understand the mechanics of tectonic tremor, transform our understanding of the depth dependence of faulting, illuminate diffusion within aftershock seismicity, and reveal new insights into induced earthquakes. These results were achieved with modest data volumes ? from ~ 10 seismic stations spanning ~ 10 km ? yet they increased the number of detected earthquakes by a factor of 10 to 100. This geoinformatics project will develop the cyberinfrastructure required to enable high-sensitivity studies of earthquake processes through the discovery of previously undetected seismic events within massive data volumes.This goal of this project is to develop a cyberinfrastructure to mine seismic waveform data. The effort will develop methods and hardware to use coherent signal processing on very large waveform databases to detect, locate and characterize events that cannot be detected by standard network operations (detection of single arrivals, association, location by optimization). The methodology involves the use of a network-based approach for earthquake detection, especially weak and unusual events that in the current method of treating signals individually go unreported. The PIs will work on the large T and the large N problem, where large T is using waveform similarity of multiple events over time to detect earthquakes over long periods of time; and the large N is using waveform similarity of single events over space as recorded on a dense seismic array with up to thousands of stations.The results will greatly increase knowledge of the number of seismic sources of various kinds and potentially identify patterns in earthquake occurrence that could inform hazard and near-term rupture forecasting. Seismicity induced by human activities is an emerging problem that adversely affects energy options for the 21st century, including shale gas development, enhanced geothermal energy, and carbon sequestration. A more complete view of seismicity related to these activities is essential to managing the risks they pose.