The 3-D seismic signature of plumes: wavefield effects and experiment optimization

羽流的 3D 地震特征：波场效应和实验优化

• 批准号: 5323096
• 负责人: Professor Dr. Heiner Igel
• 金额: --
• 依托单位: Sektion Geophysik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2001
• 资助国家: 德国
• 起止时间: 2000-12-31 至 2005-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5323096?language=en
• 关键词: seismic; signature; plumes; wavefield; effects

The detailed seismic imaging of large mantle plumes is one of the major milestones towards understanding mantle convection and the geochemical evolution of the mantle. So far seismic studies have revealed plume conduits of diameter 100 to 200 km. However, details of the 3-D structure of plumes are difficult to investigate using ray-theoretical methods, (quasi-)analytical solutions for simplified plume structures (e.g. cylinders) or long-period information (e.g. from surface waves) only. We propose to carry out an extensive study of the complete 3-D wave field of likely plume structures with the aim of (1) predicting frequency-dependent effects on amplitudes and waveforms of plume-like structures; (2) testing experimental configurations for teleseismic studies on their ability to map the deep plume structure, (3) optimizing experimental configurations for seismic refraction studies planned in the future and (4) develop processing methods to extract structural information from recorded data. The numerical simulations of the 3-D wave fields will be carried out using verified algorithms developed on high-performance computers with the ability to achieve high-frequency wavefields.

大型地幔柱的详细地震成像是了解地幔对流和地幔地球化学演化的重要里程碑之一。迄今为止，地震研究已揭示了直径为 100 至 200 公里的羽流管道。然而，仅使用射线理论方法、简化羽流结构（例如圆柱体）的（准）分析解或长周期信息（例如来自表面波）很难研究羽流 3-D 结构的细节。我们建议对可能的羽状结构的完整 3D 波场进行广泛的研究，目的是 (1) 预测对羽状结构的振幅和波形的频率相关影响； (2) 测试远震研究的实验配置是否能够绘制深部羽流结构图，(3) 优化未来计划的地震折射研究的实验配置，(4) 开发从记录数据中提取结构信息的处理方法。 3D波场的数值模拟将使用在能够实现高频波场的高性能计算机上开发的经过验证的算法进行。