Locating Scattered Energy in Vogtland's Earthquake Swarm Source Area through Double 3D-Array Beamforming and Inter-Event Coda Correlation Imaging (D3D)

通过双 3D 阵列波束形成和事件间尾相关成像 (D3D) 定位 Vogtland 地震群震源区的分散能量

• 批准号: 419909358
• 负责人: Professor Dr. Torsten Dahm
• 金额: --
• 依托单位: Institute of Geophysics
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/419909358?language=en
• 关键词: Locating; Scattered; Energy; Vogtland; Earthquake

We aim to detect and quantify the characteristics of crustal scatterers located within and around the source area of the West Bohemian / Vogtland region from transient Earthquake signals. The quantification of scattering strength and its dependence on variable angles provides insight into the nature of scatterers as structural elements and their possible physical relation with the postulated ongoing deep fluid flow. We will exploit the information from the observation of weak coda phases at multiple arrays. In order to improve the high frequency content of the observations we will install a deep borehole array beneath a classical surface array for the continuous observation of transient signals as well as the ambient vibration wave field. This 3D-array installation (receiver array / RA) will be used in combination with the reciprocal 3D array recording geometry known as source array (SA) for consistently locating weak scattered energy close and within the volume of earthquake swarm generation. Furthermore we propose to use a source to source coda correlation technique to generate an inter-source Green’s function database. This database will be derived from existing swarm data in recent years but then further augmented by observations at the newly deployed installations. It will be used to derive the velocity structure in the source volume of the swarm region and will allow investigating not only the spatial but also the temporal character of velocity anomalies as possible cause for swarm triggering or indications for fluid pathways in depth.

我们的目标是检测和量化的地壳散射体位于西波希米亚/ Vogtland地区的源区域内和周围的瞬态地震信号的特性。散射强度的量化及其对可变角度的依赖性提供了对散射体作为结构元素的性质及其与假定的持续深层流体流动的可能物理关系的洞察。我们将利用在多个阵列的弱尾波相位的观测信息。为了提高观测的高频含量，我们将在经典的表面阵列下安装一个深井阵列，用于连续观测瞬态信号以及环境振动波场。 该三维阵列装置（接收器阵列/ RA）将与称为震源阵列（SA）的互易三维阵列记录几何结构结合使用，以始终定位震群生成体积内和附近的弱散射能量。此外，我们建议使用源到源尾波相关技术来产生源间绿色函数数据库。该数据库将从近年来现有的蜂群数据中获得，但随后将通过新部署的设施的观测进一步扩大。它将被用来推导出速度结构的源体积的群区域，并将允许调查不仅是空间，而且时间特性的速度异常可能的原因群触发或指示流体路径的深度。