Seismic anisotropy and attenuation retrieved from waveform recordings of acoustic emissions and observations of natural and induced seismicity

从声发射波形记录以及自然和诱发地震活动的观测中检索地震各向异性和衰减

基本信息

批准号：
282226934
负责人：
Professor Dr. Marco Bohnhoff
金额：
--
依托单位：
Institute of Geophysics
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2016
资助国家：
德国
起止时间：
2015-12-31 至 2017-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/282226934?language=en
关键词：
Seismic anisotropy attenuation retrieved waveform

项目摘要

Analysis of seismic moment tensors is a rapidly developing field in earthquake seismology and rock physics. Hereby, isotropic medium properties are usually assumed. However, seismic observations confirm that most rocks are anisotropic and attenuating. These properties jointly affect the propagating wavefields but also properties of seismic sources. In particular, the inversion for the seismic moment tensors is more complicated and a straightforward interpretation of moment tensors in anisotropic media is not possible. The main objective of this project is to develop new methods for determining seismic anisotropy of geological structures and to apply these methods to seismically active regions with natural and induced seismicity in order to refine seismo-mechanical models towards an improved characterization of the focal zone. High quality moment and source tensors will be retrieved by applying a new method of moment tensor inversion for anisotropic and viscoelastic media. Evaluating the complete moment and source tensors in anisotropic and attenuating media will allow getting more detailed information on the geometry of fractures, the fracture processes and on the properties of the fractured rock. The results of the project will find industrial applications related to induced seismicity in hydrocarbon and geothermal reservoirs as well as detailed knowledge about increased hazard in volcanic and seismically active regions. Evaluating the complete moment tensors in anisotropic and attenuating media will allow us to get more detailed information on the geometry of fractures, the fracture processes and on the properties of fractured rock.

地震矩张量分析是地震学和岩石物理学中快速发展的领域。因此，通常假设各向同性介质属性。然而，地震观测证实大多数岩石是各向异性且衰减的。这些特性共同影响传播波场以及震源的特性。特别是，地震矩张量的反演更加复杂，并且不可能直接解释各向异性介质中的矩张量。该项目的主要目标是开发确定地质结构地震各向异性的新方法，并将这些方法应用于具有自然地震活动和诱发地震活动的地震活动区域，以改进地震力学模型，以改进震源区的表征。通过应用针对各向异性和粘弹性介质的矩张量反演新方法，将检索高质量的矩和源张量。评估各向异性和衰减介质中的完整力矩和源张量将能够获得有关裂缝几何形状、裂缝过程和裂缝岩石特性的更详细信息。该项目的结果将找到与碳氢化合物和地热储层诱发地震活动相关的工业应用，以及有关火山和地震活跃地区危险增加的详细知识。评估各向异性和衰减介质中的完整力矩张量将使我们能够获得有关裂缝几何形状、断裂过程和裂隙岩石特性的更详细信息。