Short-term Exciting, Long-term Correcting Models for Earthquake Catalogs
Short-term Exciting, Long-term Correcting Models for Earthquake Catalogs
复制标题
地震目录的短期激动、长期校正模型
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
B. Bolt
中科院分区：
文献类型：
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作者：
F. Schoenberg;B. Bolt
地震目录的短期激励、长期校正模型。统计部地质与地球物理系美国加州大学洛杉矶分校加州大学伯克利分校摘要本文介绍了一类地震发生概率模型--短期激励长期相关模型（SELC）。这一类别包括目前用于灾害分析的不同模型的特征，以描述地震目录，如F。大森它提供了一个统一的方法来分析和描述不同类型的地震目录的潜力。给出了地震活动性模型参数和标准误差的极大似然估计方法。样本SELC模型显示，提供令人满意的适合七年的目录发生在帕克菲尔德，加州和一个较长的地震活动序列从圣安德烈亚斯断层带在中部加州的微震。地震活动模式和机制的推论进行了讨论。检测到显著的聚集和应变释放。引言地震目录的两个广为人知的特点是：1）地震往往发生在集群。这种聚集既有空间上的也有时间上的，有时候用震群、前震活动、余震和Adamopoulos，1973; Kagan和Knopoff，活动（Hawkes，1984; Ogata和Tanemura，1984; Bullen和Bolt，Ogata和Katamura，1988）等术语来表示. 2)产生地震的断层破裂减少了沿断层沿着破裂发生位置的应变量。这种构造应变被认为随着时间的推移逐渐重建，最终达到临界水平，此时会产生另一场地震或地震序列（Reid，1911年; Ogata和Vere-Jones，1984年; Wang等人，1991; Ogata，1994）。几个概率模型反映了对第一种行为建模的努力。地震目录被建模为触发、分支或地震类型点过程的实现，并且所有参考模型都具有以下特征：点（x，ti）处地震的实例是点（y，？2)空间和时间上的m增加了空间和时间，其中t <特定实现的可能性可以由点过程的条件速率给出;这些模型规定，如果发生了更多的地震，地震过程的条件速率就会增加。通常假设，由于前一次地震而导致的条件速率增加的量会随着时间和距离前一次地震的距离的增加而逐渐减少。许多研究人员转而关注上面列出的地震行为的第二个方面。在某些情况下，小事件和/或余震被从考虑中的地震目录中删除（例如，
Short-term Exciting, Long-term Correcting Models for Earthquake Catalogs Frederic Schoenberg Bruce Bolt Dept. of Statistics Dept. of Geology and Geophysics University of California, Los Angeles University of California, Berkeley Abstract A class of probability models for earthquake occurrences, called Short-term Exciting Long-term Cor- recting (SELC) models, is presented. This class encompasses features of different models presently used in hazard analysis to characterize earthquake catalogs, such as that of F. Omori. It offers the potential for a unified approach to the analysis and description of different types of earthquake catalogs. Maximum likelihood estimation methods for the seismicity model parameters and standard errors are presented. Sample SELC models are shown to provide satisfactory fit to a seven-year catalog of microearthquakes occurring in Parkfield, California and a longer seismicity sequence from the San Andreas fault zone in Central California. Inferences on seismicity patterns and mechanisms are discussed. Both significant clustering and strain release are detected. Introduction Two widely noted features of earthquake catalogs are the following: 1) Earthquakes tend to occur in clusters. This clustering is both spatial and temporal, and is some- times referred to with terms such as swarms , foreshock activity , and aftershock and Adamopoulos, 1973; Kagan and Knopoff, activity (Hawkes 1984; Ogata and Tanemura, 1984; Bullen and Bolt, Ogata and Katsura, 1988). 2) The fault ruptures that generate earthquakes decrease the amount of strain present at the locations along the fault where rupture occurs. This tectonic strain is thought to rebuild gradually over time, eventually achieving a critical level at which time another earthquake, or sequence of earthquakes, is generated (Reid, 1911; Ogata and Vere-Jones, 1984; Wang et al., 1991; Ogata, 1994). Several probability models reflect efforts at modeling this first type of behavior. Earthquake catalogs are modeled as realizations of triggering, branching or epidemic-type point processes, and all the referenced models have the feature that the instance of an earthquake at point (x,ti) the likelihood of an earthquake at point (y,?2) m in space and time increases space and time, where t < The likelihood of a particular realization may be given by the conditional rate of the point process; these models prescribe that the conditional rate of the earthquake process increases if more earthquakes have occurred. The amount which the conditional rate increases as a result of one previous earthquake is generally assumed to taper off as both time and distance from the previous earthquake increase. Numerous researchers have instead focused on the second facet of earthquake behavior listed above. In some cases small events and/or aftershocks are removed from earthquake catalogs under consideration (e.g.