...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Pure and Applied Geophysics >Applying Depth Distribution of Seismicity to Determine Thermo-Mechanical Properties of the Seismogenic Crust in Southern California: Comparing Lithotectonic Blocks
【24h】

Applying Depth Distribution of Seismicity to Determine Thermo-Mechanical Properties of the Seismogenic Crust in Southern California: Comparing Lithotectonic Blocks

机译：应用地震性的深度分布，测定南加州南部地壳地壳的热力学性能：比较岩石块

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We analyze waveform-relocated seismicity (1981-2016) and other geophysical and geological datasets from 16 lithotectonic crustal blocks in southern California. We explore how earthquake depth histograms (EDH) are related to crustal strength, lithology, and temperature of the crust. First, we calculate relative EDHs to quantify the depth distribution of seismicity for each lithotectonic block. Second, we calculate depth profiles of maximum differential stress (yield strength envelopes, YSEs) using Byerlee's law and a non-linear dislocation creep law. We use observed average heat flow values, strain rates, and states of stress to parameterize YSEs for five different crustal candidate lithologies in each lithotectonic block. We assume that seismicity ceases where the mechanical rock strength falls below a critical threshold level, and identify the YSE that best predicts the depth extent of seismicity in each block. The lithologies of the best matching YSEs are found to agree well with expectations from past tectonics: they are mostly quartz-dominated except for the feldspar-rich diorite lithologies in the Great Valley, the southernmost western Sierra Nevada, Inner Continental Borderland, and Rifted crust in the Salton Trough. Similarly, the inferred thermo-mechanical properties, including differential stress, lithology, and geotherms reflect the previously mapped tectonic variability between the 16 lithotectonic blocks. On average, the differential yield stress is smaller and peaks at a shallower depth in hotter and more quartz rich crust but is larger and peaks at greater depths for colder and predominantly diorite crust. The good agreement between the modeled YSEs, the EDHs and tectonic considerations suggests that EDHs indeed reflect long-term geophysical properties of the crust and can be used to infer thermo-mechanical properties at depth. In contrast, shallow seismicity may be more likely to reflect short-term strain transients from fluid flow or recent anthropog
机译：我们分析了来自南加州的16个型岩石地壳区块的波形重定位的地震性和地球物理和地质数据集。我们探索地震深度直方图（EDH）是如何与地壳的地壳强度，岩性和温度有关。首先，我们计算相对EDH来量化每个径向块的地震性的深度分布。其次，我们计算最大差分应力（屈服强度信封，YSE）的深度谱，使用Byerlee法和非线性错位蠕变法。我们使用观察到的平均热流量值，应变率和应力的状态，在每个径程块中的五种不同地壳候选岩性的参数化yses。我们假设地震性停止在机械岩石强度低于临界阈值水平的情况下停止，并且识别最能预测每个块中地震性的深度范围的ySE。发现最佳匹配YSE的岩性与过去的构造中的期望相同，除了在大谷的长石富含Diority岩石，南部最富有的西蒙达，内部的边境和裂谷外在萨尔顿槽中。类似地，推断的热机械性能，包括微分应力，岩性和地热反映了16个型型碎片块之间的先前映射的构造变异性。平均而言，差动屈服应力较小，在较浅层的深度较小，富含石英的地壳的峰值较大，但更大，较大的深度较大，主要是较冷，主要是尖端的地壳。所建模的YSE，EDH和构造考虑因素之间的良好一致性表明EDHS确实反映了地壳的长期地球物理性质，可用于在深度推断热机械性能。相比之下，浅地震性可能更有可能反射来自流体流动或最近的人类的短期应变瞬变

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号