首页 > 最新文献

Bulletin of the Seismological Society of America最新文献

英文 中文
Kinematic Rupture Model of the 6 February 2023 Mw 7.8 Türkiye Earthquake from a Large Set of Near-Source Strong-Motion Records Combined with GNSS Offsets Reveals Intermittent Supershear Rupture 2023年2月6日大震源强震记录结合GNSS偏移的7.8级<s:1> rkiye地震运动学破裂模型揭示了间歇性超剪切破裂
3区 地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2023-11-09 DOI: 10.1785/0120230077
Bertrand Delouis, Martijn van den Ende, Jean-Paul Ampuero
ABSTRACT The 2023 Mw 7.8 southeast Türkiye earthquake was recorded by an unprecedentedly large set of strong-motion stations very close to its rupture, opening the opportunity to observe the rupture process of a large earthquake with fine resolution. Here, the kinematics of the earthquake source are inferred by finite-source inversion based on strong-motion records and coseismic offsets from permanent Global Navigation Satellite Systems stations. The strong-motion records at stations NAR and 4615, which are the closest to the splay fault (SPF) where the rupture initiated and which were previously interpreted to contain the signature of supershear rupture speeds, are successfully modeled here by a subshear rupture propagating unilaterally to the northeast. Once the rupture on the SPF reaches the east Anatolian fault (EAF), it propagates on the EAF bilaterally, extending about 120 km northeast and 180 km southwest. To the south, the depth extent of the rupture decreases, as it passes a bend of the EAF. Although the rupture velocity remains globally subshear along the EAF, we identify three portions of the fault where the rupture is transiently supershear. The transitions to supershear speed coincide with regions of reduced fault slip, which suggests supershear bursts generated by the failure of local rupture barriers. Toward the southwest termination, the rupture encircles an asperity before its failure, which is a feature that has been observed only on rare occasions. This unprecedented detail of the inversion was facilitated by the proximity to the fault and the exceptional density of the accelerometric network in the area.
2023 Mw 7.8级东南震源基耶耶大地震是史无前例的大型强震台站在离震源破裂非常近的地方记录下来的,这为以精细分辨率观测大地震的破裂过程提供了机会。在这里,震源的运动学是通过基于强震记录和永久全球导航卫星系统站的同震偏移量的有限源反演来推断的。NAR和4615站的强震记录最接近破裂发生的张开断层(SPF),以前被解释为包含超剪切破裂速度的特征,在这里成功地通过向东北单方面传播的亚剪切破裂来模拟。一旦SPF上的破裂到达东安纳托利亚断层(EAF),它就会在EAF上双向传播,向东北延伸约120公里,向西南延伸约180公里。在南部,破裂的深度范围减小,因为它通过一个EAF的弯曲。虽然沿东断裂带的破裂速度总体上保持亚剪切,但我们确定了断层的三个部分,其中破裂是短暂的超剪切。向超剪切速度的转变与断层滑动减少的区域一致,这表明局部破裂屏障的破坏产生了超剪切爆发。在西南端,破裂在破裂之前环绕着一个粗糙体,这是一个很少被观察到的特征。这一前所未有的反演细节得益于断层附近和该地区加速度测量网络的异常密度。
{"title":"Kinematic Rupture Model of the 6 February 2023 Mw 7.8 Türkiye Earthquake from a Large Set of Near-Source Strong-Motion Records Combined with GNSS Offsets Reveals Intermittent Supershear Rupture","authors":"Bertrand Delouis, Martijn van den Ende, Jean-Paul Ampuero","doi":"10.1785/0120230077","DOIUrl":"https://doi.org/10.1785/0120230077","url":null,"abstract":"ABSTRACT The 2023 Mw 7.8 southeast Türkiye earthquake was recorded by an unprecedentedly large set of strong-motion stations very close to its rupture, opening the opportunity to observe the rupture process of a large earthquake with fine resolution. Here, the kinematics of the earthquake source are inferred by finite-source inversion based on strong-motion records and coseismic offsets from permanent Global Navigation Satellite Systems stations. The strong-motion records at stations NAR and 4615, which are the closest to the splay fault (SPF) where the rupture initiated and which were previously interpreted to contain the signature of supershear rupture speeds, are successfully modeled here by a subshear rupture propagating unilaterally to the northeast. Once the rupture on the SPF reaches the east Anatolian fault (EAF), it propagates on the EAF bilaterally, extending about 120 km northeast and 180 km southwest. To the south, the depth extent of the rupture decreases, as it passes a bend of the EAF. Although the rupture velocity remains globally subshear along the EAF, we identify three portions of the fault where the rupture is transiently supershear. The transitions to supershear speed coincide with regions of reduced fault slip, which suggests supershear bursts generated by the failure of local rupture barriers. Toward the southwest termination, the rupture encircles an asperity before its failure, which is a feature that has been observed only on rare occasions. This unprecedented detail of the inversion was facilitated by the proximity to the fault and the exceptional density of the accelerometric network in the area.","PeriodicalId":9444,"journal":{"name":"Bulletin of the Seismological Society of America","volume":" 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135241831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Reply to “Comment on ‘Effect of Style of Faulting on the Orientation of Maximum Horizontal Earthquake Response Spectra’ by Alan Poulos and Eduardo Miranda” by Paul Somerville 回复Paul Somerville的“关于Alan Poulos和Eduardo Miranda的‘断层类型对最大水平地震反应谱方向的影响’的评论”
3区 地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2023-11-09 DOI: 10.1785/0120230223
Alan Poulos, Eduardo Miranda
Reply| November 09, 2023 Reply to “Comment on ‘Effect of Style of Faulting on the Orientation of Maximum Horizontal Earthquake Response Spectra’ by Alan Poulos and Eduardo Miranda” by Paul Somerville Alan Poulos; Alan Poulos * 1Department of Civil and Environmental Engineering, Stanford University, Stanford, California, U.S.A. *Corresponding author: apoulos@stanford.edu https://orcid.org/0000-0001-8654-1024 Search for other works by this author on: GSW Google Scholar Eduardo Miranda Eduardo Miranda 1Department of Civil and Environmental Engineering, Stanford University, Stanford, California, U.S.A. https://orcid.org/0000-0001-9398-443X Search for other works by this author on: GSW Google Scholar Author and Article Information Alan Poulos https://orcid.org/0000-0001-8654-1024 * 1Department of Civil and Environmental Engineering, Stanford University, Stanford, California, U.S.A. Eduardo Miranda https://orcid.org/0000-0001-9398-443X 1Department of Civil and Environmental Engineering, Stanford University, Stanford, California, U.S.A. *Corresponding author: apoulos@stanford.edu Publisher: Seismological Society of America First Online: 09 Nov 2023 Online ISSN: 1943-3573 Print ISSN: 0037-1106 © Seismological Society of America Bulletin of the Seismological Society of America (2023) https://doi.org/10.1785/0120230223 Article history First Online: 09 Nov 2023 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Alan Poulos, Eduardo Miranda; Reply to “Comment on ‘Effect of Style of Faulting on the Orientation of Maximum Horizontal Earthquake Response Spectra’ by Alan Poulos and Eduardo Miranda” by Paul Somerville. Bulletin of the Seismological Society of America 2023; doi: https://doi.org/10.1785/0120230223 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin of the Seismological Society of America Search Advanced Search We thank Somerville (2023) for the comment on our article (Poulos and Miranda, 2023), which found that the orientation of maximum horizontal spectral response tends to be close to the transverse orientation with respect to the epicenter of strike‐slip earthquakes. Herein, we respond to the main points of the comment, following the order in which they were made. In the comment, Somerville (2023) mentions that “Using a point‐source model of the earthquake source, they find that…”. It should be noted that in our study, we do not explicitly use a point‐source model other than when computing the transverse... You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
回复| 2023年11月9日回复Paul Somerville Alan Poulos的“关于Alan Poulos和Eduardo Miranda的‘断层类型对最大水平地震反应谱方向的影响’的评论”;Alan Poulos * 1美国加利福尼亚州斯坦福大学土木与环境工程系*通讯作者:apoulos@stanford.edu https://orcid.org/0000-0001-8654-1024查找作者其他著作请访问:GSW谷歌学者Eduardo Miranda Eduardo Miranda 1美国加利福尼亚州斯坦福大学土木与环境工程系https://orcid.org/0000-0001-9398-443X查找作者其他著作请访问:GSW Google Scholar作者与文章信息Alan Poulos https://orcid.org/0000-0001-8654-1024 * 1美国斯坦福大学土木与环境工程系Eduardo Miranda https://orcid.org/0000-0001-9398-443X 1美国斯坦福大学土木与环境工程系*通讯作者:apoulos@stanford.edu出版单位:美国地震学会First Online: 2023年11月9日1943-3573印刷ISSN: 0037-1106©美国地震学会美国地震学会公报(2023)https://doi.org/10.1785/0120230223文章历史首次在线:2023年11月9日引用查看此引文添加到引文管理器共享图标共享Facebook Twitter LinkedIn电子邮件权限搜索网站引文Alan Poulos, Eduardo Miranda;回复Paul Somerville的“关于Alan Poulos和Eduardo Miranda的‘断层类型对最大水平地震反应谱方向的影响’的评论”。美国地震学会公报2023;doi: https://doi.org/10.1785/0120230223下载引文文件:Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex工具栏搜索搜索下拉菜单工具栏搜索搜索输入搜索输入自动建议过滤您的搜索所有内容美国地震学会公报搜索高级搜索我们感谢Somerville(2023)对我们的文章(Poulos和Miranda, 2023)的评论。研究发现,相对于走滑地震的震中,最大水平谱响应的方向趋向于接近横向方向。在此,我们按照评论的顺序对其要点作出回应。在评论中,Somerville(2023)提到“使用震源的点源模型,他们发现……”。值得注意的是,在我们的研究中,我们没有明确地使用点源模型,除了计算横向…您没有访问此内容的权限,如果您觉得您应该有权访问,请与您的机构管理员联系。
{"title":"Reply to “Comment on ‘Effect of Style of Faulting on the Orientation of Maximum Horizontal Earthquake Response Spectra’ by Alan Poulos and Eduardo Miranda” by Paul Somerville","authors":"Alan Poulos, Eduardo Miranda","doi":"10.1785/0120230223","DOIUrl":"https://doi.org/10.1785/0120230223","url":null,"abstract":"Reply| November 09, 2023 Reply to “Comment on ‘Effect of Style of Faulting on the Orientation of Maximum Horizontal Earthquake Response Spectra’ by Alan Poulos and Eduardo Miranda” by Paul Somerville Alan Poulos; Alan Poulos * 1Department of Civil and Environmental Engineering, Stanford University, Stanford, California, U.S.A. *Corresponding author: apoulos@stanford.edu https://orcid.org/0000-0001-8654-1024 Search for other works by this author on: GSW Google Scholar Eduardo Miranda Eduardo Miranda 1Department of Civil and Environmental Engineering, Stanford University, Stanford, California, U.S.A. https://orcid.org/0000-0001-9398-443X Search for other works by this author on: GSW Google Scholar Author and Article Information Alan Poulos https://orcid.org/0000-0001-8654-1024 * 1Department of Civil and Environmental Engineering, Stanford University, Stanford, California, U.S.A. Eduardo Miranda https://orcid.org/0000-0001-9398-443X 1Department of Civil and Environmental Engineering, Stanford University, Stanford, California, U.S.A. *Corresponding author: apoulos@stanford.edu Publisher: Seismological Society of America First Online: 09 Nov 2023 Online ISSN: 1943-3573 Print ISSN: 0037-1106 © Seismological Society of America Bulletin of the Seismological Society of America (2023) https://doi.org/10.1785/0120230223 Article history First Online: 09 Nov 2023 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Alan Poulos, Eduardo Miranda; Reply to “Comment on ‘Effect of Style of Faulting on the Orientation of Maximum Horizontal Earthquake Response Spectra’ by Alan Poulos and Eduardo Miranda” by Paul Somerville. Bulletin of the Seismological Society of America 2023; doi: https://doi.org/10.1785/0120230223 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin of the Seismological Society of America Search Advanced Search We thank Somerville (2023) for the comment on our article (Poulos and Miranda, 2023), which found that the orientation of maximum horizontal spectral response tends to be close to the transverse orientation with respect to the epicenter of strike‐slip earthquakes. Herein, we respond to the main points of the comment, following the order in which they were made. In the comment, Somerville (2023) mentions that “Using a point‐source model of the earthquake source, they find that…”. It should be noted that in our study, we do not explicitly use a point‐source model other than when computing the transverse... You do not have access to this content, please speak to your institutional administrator if you feel you should have access.","PeriodicalId":9444,"journal":{"name":"Bulletin of the Seismological Society of America","volume":" 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135241842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Enhancement of Seismic Phase Identification Using Polarization Filtering and Array Analysis 利用极化滤波和阵列分析增强地震相位识别
3区 地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2023-11-07 DOI: 10.1785/0120230135
On Ki Angel Ling, Simon C. Stähler, David Sollberger, Domenico Giardini
ABSTRACT Seismic arrays play a crucial role in identifying weak signals in the seismic wavefield based on their expected slowness and backazimuth values. However, their resolution power is limited when studying phases with similar horizontal slownesses and arrival times, such as receiver-side or source-side reverberations and converted phases. Therefore, we investigate the benefit of applying polarization filtering to three-component seismograms before stacking to remove undesired signals and increase the signal-to-noise ratio of the array. Customized polarization filters enable more sophisticated wavefield separation and robust phase identification on vespagrams. However, selecting the suitable polarization filter requires a balance between noise reduction and the preservation of desired signals. We find that degree-of-polarization filters generally excel in suppressing incoherent noise. On the other hand, some filters, for example, based solely on ellipticity, do not yield notable enhancements for body waves and may even produce adverse effects, specifically for phases that arrive late in the seismogram. We demonstrate these findings using data recorded by AlpArray and surrounding permanent stations.
地震阵在识别地震波场中的弱信号方面发挥着至关重要的作用,这些信号是基于地震波场的预期慢度和反方位角值来识别的。然而,当研究具有相似水平慢度和到达时间的相位时,例如接收端或源端混响和转换相位,它们的分辨能力受到限制。因此,我们研究了在叠加前对三分量地震图进行极化滤波的好处,以去除不希望的信号并提高阵列的信噪比。定制偏振滤波器使更复杂的波场分离和可靠的相位识别。然而,选择合适的极化滤波器需要在降噪和保留所需信号之间取得平衡。我们发现偏振度滤波器通常在抑制非相干噪声方面表现优异。另一方面,一些滤波器,例如,完全基于椭圆性,对体波没有显著的增强效果,甚至可能产生不利影响,特别是对地震记录中较晚到达的相位。我们使用AlpArray和周围永久站点记录的数据来证明这些发现。
{"title":"Enhancement of Seismic Phase Identification Using Polarization Filtering and Array Analysis","authors":"On Ki Angel Ling, Simon C. Stähler, David Sollberger, Domenico Giardini","doi":"10.1785/0120230135","DOIUrl":"https://doi.org/10.1785/0120230135","url":null,"abstract":"ABSTRACT Seismic arrays play a crucial role in identifying weak signals in the seismic wavefield based on their expected slowness and backazimuth values. However, their resolution power is limited when studying phases with similar horizontal slownesses and arrival times, such as receiver-side or source-side reverberations and converted phases. Therefore, we investigate the benefit of applying polarization filtering to three-component seismograms before stacking to remove undesired signals and increase the signal-to-noise ratio of the array. Customized polarization filters enable more sophisticated wavefield separation and robust phase identification on vespagrams. However, selecting the suitable polarization filter requires a balance between noise reduction and the preservation of desired signals. We find that degree-of-polarization filters generally excel in suppressing incoherent noise. On the other hand, some filters, for example, based solely on ellipticity, do not yield notable enhancements for body waves and may even produce adverse effects, specifically for phases that arrive late in the seismogram. We demonstrate these findings using data recorded by AlpArray and surrounding permanent stations.","PeriodicalId":9444,"journal":{"name":"Bulletin of the Seismological Society of America","volume":"291 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135474706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Evidence of Seattle Fault Earthquakes from Patterns in Deep-Seated Landslides 来自深层滑坡模式的西雅图断层地震证据
3区 地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2023-11-07 DOI: 10.1785/0120230079
Erich Herzig, Alison Duvall, Adam Booth, Ian Stone, Erin Wirth, Sean LaHusen, Joseph Wartman, Alex Grant
ABSTRACT Earthquake-induced landslides can record information about the seismic shaking that generated them. In this study, we present new mapping, Light Detection and Ranging-derived roughness dating, and analysis of over 1000 deep-seated landslides from the Puget Lowlands of Washington, U.S.A., to probe the landscape for past Seattle fault earthquake information. With this new landslide inventory, we observe spatial and temporal evidence of landsliding related to the last major earthquake on the Seattle fault ∼1100 yr before present. We find spatial clusters of landslides that correlate with ground motions from recent 3D kinematic models of Seattle fault earthquakes. We also find temporal patterns in the landslide inventory that suggest earthquake-driven increases in landsliding. We compare the spatial and temporal landslide data with scenario-based ground motion models and find stronger evidence of the last major Seattle fault earthquake from this combined analysis than from spatial or temporal patterns alone. We also compare the landslide inventory with ground motions from different Seattle fault earthquake scenarios to determine the ground motion distributions that are most consistent with the landslide record. We find that earthquake scenarios that best match the clustering of ∼1100-year-old landslides produce the strongest shaking within a band that stretches from west to east across central Seattle as well as along the bluffs bordering the broader Puget Sound. Finally, we identify other landslide clusters (at 4.6–4.2 ka, 4.0–3.8 ka, 2.8–2.6 ka, and 2.2–2.0 ka) in the inventory which let us infer potential ground motions that may correspond to older Seattle fault earthquakes. Our method, which combines hindcasting of the surface response to the last major Seattle fault earthquake, using a roughness-aged landslide inventory with forecasts of modeled ground shaking from 3D seismic scenarios, showcases a powerful new approach to gleaning paleoseismic information from landscapes.
地震诱发的山体滑坡可以记录产生山体滑坡的地震震动信息。在这项研究中,我们提出了新的制图,光探测和测距衍生的粗糙度测年,并分析了来自美国华盛顿普吉特低地的1000多个深层滑坡,以探测过去西雅图断层地震信息的景观。利用这一新的滑坡清单,我们观察到与西雅图断层上一次大地震有关的滑坡的时空证据。我们从最近的西雅图断层地震的三维运动学模型中发现了与地面运动相关的滑坡空间集群。我们还发现滑坡清单中的时间模式表明地震驱动的滑坡增加。我们将空间和时间滑坡数据与基于场景的地面运动模型进行了比较,并从这种组合分析中发现了比单独的空间或时间模式更有力的西雅图断层大地震证据。我们还将滑坡库存与不同西雅图断层地震情景的地面运动进行了比较,以确定与滑坡记录最一致的地面运动分布。我们发现,与大约1100年前的山体滑坡集群最匹配的地震情景,在从西到东横跨西雅图中部以及沿着与更广阔的普吉特海湾接壤的悬崖延伸的带内产生了最强烈的震动。最后,我们在清单中确定了其他滑坡群(4.6-4.2 ka, 4.0-3.8 ka, 2.8-2.6 ka和2.2-2.0 ka),这让我们推断出可能对应于更古老的西雅图断层地震的潜在地面运动。我们的方法结合了对上一次西雅图断层大地震的地表响应的后推,使用粗糙年龄的滑坡清单和3D地震情景模拟的地面震动预测,展示了一种从景观中收集古地震信息的强大新方法。
{"title":"Evidence of Seattle Fault Earthquakes from Patterns in Deep-Seated Landslides","authors":"Erich Herzig, Alison Duvall, Adam Booth, Ian Stone, Erin Wirth, Sean LaHusen, Joseph Wartman, Alex Grant","doi":"10.1785/0120230079","DOIUrl":"https://doi.org/10.1785/0120230079","url":null,"abstract":"ABSTRACT Earthquake-induced landslides can record information about the seismic shaking that generated them. In this study, we present new mapping, Light Detection and Ranging-derived roughness dating, and analysis of over 1000 deep-seated landslides from the Puget Lowlands of Washington, U.S.A., to probe the landscape for past Seattle fault earthquake information. With this new landslide inventory, we observe spatial and temporal evidence of landsliding related to the last major earthquake on the Seattle fault ∼1100 yr before present. We find spatial clusters of landslides that correlate with ground motions from recent 3D kinematic models of Seattle fault earthquakes. We also find temporal patterns in the landslide inventory that suggest earthquake-driven increases in landsliding. We compare the spatial and temporal landslide data with scenario-based ground motion models and find stronger evidence of the last major Seattle fault earthquake from this combined analysis than from spatial or temporal patterns alone. We also compare the landslide inventory with ground motions from different Seattle fault earthquake scenarios to determine the ground motion distributions that are most consistent with the landslide record. We find that earthquake scenarios that best match the clustering of ∼1100-year-old landslides produce the strongest shaking within a band that stretches from west to east across central Seattle as well as along the bluffs bordering the broader Puget Sound. Finally, we identify other landslide clusters (at 4.6–4.2 ka, 4.0–3.8 ka, 2.8–2.6 ka, and 2.2–2.0 ka) in the inventory which let us infer potential ground motions that may correspond to older Seattle fault earthquakes. Our method, which combines hindcasting of the surface response to the last major Seattle fault earthquake, using a roughness-aged landslide inventory with forecasts of modeled ground shaking from 3D seismic scenarios, showcases a powerful new approach to gleaning paleoseismic information from landscapes.","PeriodicalId":9444,"journal":{"name":"Bulletin of the Seismological Society of America","volume":"291 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135474712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Upper Plate and Subduction Interface Deformation Models in the 2022 Revision of the Aotearoa New Zealand National Seismic Hazard Model 新西兰国家地震灾害模型2022年修订版中的上板块和俯冲界面变形模型
3区 地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2023-11-03 DOI: 10.1785/0120230118
Russ J. Van Dissen, Kaj M. Johnson, Hannu Seebeck, Laura M. Wallace, Chris Rollins, Jeremy Maurer, Matthew C. Gerstenberger, Charles A. Williams, Ian J. Hamling, Andrew Howell, Christopher J. DiCaprio
ABSTRACT As part of the 2022 revision of the Aotearoa New Zealand National Seismic Hazard Model (NZ NSHM 2022), deformation models were constructed for the upper plate faults and subduction interfaces that impact ground-shaking hazard in New Zealand. These models provide the locations, geometries, and slip rates of the earthquake-producing faults in the NZ NSHM 2022. For upper plate faults, two deformation models were developed: a geologic model derived directly from the fault geometries and geologic slip rates in the NZ Community Fault Model version 1.0 (NZ CFM v.1.0); and a geodetic model that uses the same faults and fault geometries and derives fault slip-deficit rates by inverting geodetic strain rates for back slip on those specified faults. The two upper plate deformation models have similar total moment rates, but the geodetic model has higher slip rates on low-slip-rate faults, and the geologic model has higher slip rates on higher-slip-rate faults. Two deformation models are developed for the Hikurangi–Kermadec subduction interface. The Hikurangi–Kermadec geometry is a linear blend of the previously published interface models. Slip-deficit rates on the Hikurangi portion of the deformation model are updated from the previously published block models, and two end member models are developed to represent the alternate hypotheses that the interface is either frictionally locked or creeping at the trench. The locking state in the Kermadec portion is less well constrained, and a single slip-deficit rate model is developed based on plate convergence rate and coupling considerations. This single Kermadec realization is blended with each of the two Hikurangi slip-deficit rate models to yield two overall Hikurangi–Kermadec deformation models. The Puysegur subduction interface deformation model is based on geometry taken directly from the NZ CFM v.1.0, and a slip-deficit rate derived from published geodetic plate convergence rate and interface coupling estimates.
作为2022年新西兰国家地震灾害模型(NZ NSHM 2022)修订的一部分,建立了影响新西兰地震灾害的上板块断裂和俯冲界面的变形模型。这些模型提供了新西兰NSHM 2022地震断层的位置、几何形状和滑动速率。对于上板块断层,开发了两种变形模型:一种是直接从断层几何形状和新西兰社区断层模型1.0版(NZ CFM v.1.0)中的地质滑动率推导出来的地质模型;还有一个大地测量模型,它使用相同的断层和断层几何形状,并通过反演这些特定断层上的回滑的大地测量应变率来得出断层滑动亏缺率。两种上板块变形模型具有相似的总弯矩速率,但大地模型在低滑速断层上具有较高的滑动速率,地质模型在高滑速断层上具有较高的滑动速率。建立了Hikurangi-Kermadec俯冲界面的两种变形模型。Hikurangi-Kermadec几何是先前发表的界面模型的线性混合。变形模型的Hikurangi部分的滑移亏缺率根据先前发布的块体模型进行了更新,并开发了两个端部模型来表示界面在沟槽处摩擦锁定或爬行的替代假设。Kermadec部分的锁定状态约束较差,基于板块收敛速率和耦合考虑建立了单滑移亏缺率模型。这种单一的Kermadec实现与两种Hikurangi滑动亏缺率模型混合,产生两种整体的Hikurangi - Kermadec变形模型。Puysegur俯冲界面变形模型基于直接从NZ CFM v.1.0中获取的几何形状,以及根据已公布的大地板块收敛速率和界面耦合估计得出的滑动亏缺率。
{"title":"Upper Plate and Subduction Interface Deformation Models in the 2022 Revision of the Aotearoa New Zealand National Seismic Hazard Model","authors":"Russ J. Van Dissen, Kaj M. Johnson, Hannu Seebeck, Laura M. Wallace, Chris Rollins, Jeremy Maurer, Matthew C. Gerstenberger, Charles A. Williams, Ian J. Hamling, Andrew Howell, Christopher J. DiCaprio","doi":"10.1785/0120230118","DOIUrl":"https://doi.org/10.1785/0120230118","url":null,"abstract":"ABSTRACT As part of the 2022 revision of the Aotearoa New Zealand National Seismic Hazard Model (NZ NSHM 2022), deformation models were constructed for the upper plate faults and subduction interfaces that impact ground-shaking hazard in New Zealand. These models provide the locations, geometries, and slip rates of the earthquake-producing faults in the NZ NSHM 2022. For upper plate faults, two deformation models were developed: a geologic model derived directly from the fault geometries and geologic slip rates in the NZ Community Fault Model version 1.0 (NZ CFM v.1.0); and a geodetic model that uses the same faults and fault geometries and derives fault slip-deficit rates by inverting geodetic strain rates for back slip on those specified faults. The two upper plate deformation models have similar total moment rates, but the geodetic model has higher slip rates on low-slip-rate faults, and the geologic model has higher slip rates on higher-slip-rate faults. Two deformation models are developed for the Hikurangi–Kermadec subduction interface. The Hikurangi–Kermadec geometry is a linear blend of the previously published interface models. Slip-deficit rates on the Hikurangi portion of the deformation model are updated from the previously published block models, and two end member models are developed to represent the alternate hypotheses that the interface is either frictionally locked or creeping at the trench. The locking state in the Kermadec portion is less well constrained, and a single slip-deficit rate model is developed based on plate convergence rate and coupling considerations. This single Kermadec realization is blended with each of the two Hikurangi slip-deficit rate models to yield two overall Hikurangi–Kermadec deformation models. The Puysegur subduction interface deformation model is based on geometry taken directly from the NZ CFM v.1.0, and a slip-deficit rate derived from published geodetic plate convergence rate and interface coupling estimates.","PeriodicalId":9444,"journal":{"name":"Bulletin of the Seismological Society of America","volume":"42 12","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135820027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Deep Learning-Based Microseismic Detection and Location Reveal the Seismic Characteristics and Causes in the Xiluodu Reservoir, China 基于深度学习的微地震探测与定位揭示溪洛渡储层地震特征及成因
3区 地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2023-11-01 DOI: 10.1785/0120230134
Ziyi Li, Lianqing Zhou, Mengqiao Duan, Cuiping Zhao
ABSTRACT The Xiluodu reservoir, as the third reservoir developed in the lower Jinsha River, is the fourth largest reservoir in the world in terms of power generation. It is located in an area of historically high seismic intensity. A large amount of seismic activity has occurred in the reservoir area because the reservoir was impounded in 2013, but the mechanism of seismogenesis is still not clear. In this study, we collected continuous seismic records from July 2020 to October 2022 in the Xiluodu reservoir area, built a high-precision microseismic catalog for this region based on a deep learning seismic detection and location workflow called LOC-FLOW, and eventually obtained high-precision locations of 4924 earthquakes (five times more than the routine catalog). We sketched the main seismogenic structures based on the spatial and temporal distribution of the earthquakes in the catalog. According to the relationship between periodic variation of water level and seismic activity, seismicity in the reservoir area is active at the stage when the water level is filling to the highest point and starts to draw down. Especially, the sudden change in the rate of water level variation can easily trigger seismic activity. Combined with the spatiotemporal distribution of seismicity in each region and the previous results of numerical simulation, we concluded that the seismic activity in the reservoir head area and around the Manao fault is likely induced by the increase of normal stress and pore pressure diffusion caused by reservoir impoundment, whereas the ML 4.6 earthquake that occurred at the intersection of the Lianfeng fault and the Zhongcun fault was likely tectonic activity occurring on a concealed fault.
溪洛渡水库是金沙江下游开发的第三座水库,是世界上发电量第四大的水库。它位于历史上地震强度高的地区。2013年水库蓄水后,库区发生了大量地震活动,但地震发生机制尚不清楚。本研究收集了溪洛渡库区2020年7月至2022年10月的连续地震记录,基于深度学习地震检测定位工作流LOC-FLOW建立了该地区高精度微地震目录,最终获得4924次地震的高精度定位(比常规目录多5倍)。我们根据目录中地震的时空分布,勾勒出主要的发震构造。根据水位周期性变化与地震活动性的关系,库区地震活动性在水位达到最高点后开始下降的阶段较为活跃。特别是,水位变化率的突然变化很容易引发地震活动。结合各区域地震活动的时空分布特征和前人的数值模拟结果,认为库头区和马诺断裂带附近的地震活动可能是由于水库蓄水引起的正应力和孔压扩散增大引起的,而发生在莲峰断裂带和中村断裂带交汇处的ML 4.6地震可能是发生在隐伏断裂带上的构造活动。
{"title":"Deep Learning-Based Microseismic Detection and Location Reveal the Seismic Characteristics and Causes in the Xiluodu Reservoir, China","authors":"Ziyi Li, Lianqing Zhou, Mengqiao Duan, Cuiping Zhao","doi":"10.1785/0120230134","DOIUrl":"https://doi.org/10.1785/0120230134","url":null,"abstract":"ABSTRACT The Xiluodu reservoir, as the third reservoir developed in the lower Jinsha River, is the fourth largest reservoir in the world in terms of power generation. It is located in an area of historically high seismic intensity. A large amount of seismic activity has occurred in the reservoir area because the reservoir was impounded in 2013, but the mechanism of seismogenesis is still not clear. In this study, we collected continuous seismic records from July 2020 to October 2022 in the Xiluodu reservoir area, built a high-precision microseismic catalog for this region based on a deep learning seismic detection and location workflow called LOC-FLOW, and eventually obtained high-precision locations of 4924 earthquakes (five times more than the routine catalog). We sketched the main seismogenic structures based on the spatial and temporal distribution of the earthquakes in the catalog. According to the relationship between periodic variation of water level and seismic activity, seismicity in the reservoir area is active at the stage when the water level is filling to the highest point and starts to draw down. Especially, the sudden change in the rate of water level variation can easily trigger seismic activity. Combined with the spatiotemporal distribution of seismicity in each region and the previous results of numerical simulation, we concluded that the seismic activity in the reservoir head area and around the Manao fault is likely induced by the increase of normal stress and pore pressure diffusion caused by reservoir impoundment, whereas the ML 4.6 earthquake that occurred at the intersection of the Lianfeng fault and the Zhongcun fault was likely tectonic activity occurring on a concealed fault.","PeriodicalId":9444,"journal":{"name":"Bulletin of the Seismological Society of America","volume":"125 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135326082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Construction of a Ground-Motion Logic Tree through Host-to-Target Region Adjustments Applied to an Adaptable Ground-Motion Prediction Model: An Addendum 应用于自适应地动预测模型的主目标区调整地动逻辑树的构建:增编
3区 地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2023-10-31 DOI: 10.1785/0120230143
David M. Boore
ABSTRACT Boore et al. (2022; hereafter, Bea22) described adjustments to a host-region ground-motion prediction model (GMPM) for use in hazard calculations in a target region, using Chiou and Youngs (2014; hereafter, CY14) as the host-region model. This article contains two modifications to the Bea22 procedures for the host-to-target adjustments, one for the source and one for the anelastic attenuation function. The first modification is to compute logic-tree branches for the source adjustment variable ΔcM given in Bea22 assuming that the host- and target-region stress parameters are uncorrelated, instead of the implicit assumption in Bea22 that they are perfectly correlated. The assumption of uncorrelated stress parameters makes little difference for the example in Bea22 because the standard deviation of the host-region stress parameter is much less than that of the target-region stress parameter. However, this might not be the case in some future applications. The second modification is to the host-to-target anelastic attenuation path adjustment. The adjustment in Bea22 involves a distance-independent change in the γ variable that controls the rate of anelastic attenuation in the CY14 GMPM. This article proposes a method to account for a distance dependence in the adjustment. Such a dependence is needed for short-period ground-motion intensity measures (GMIMs) at distances greater than 100 km, with the importance increasing with distance. For the example in Bea22, the ratio of GMIMs computed with the revised and the previous adjustment to γ is less than about a factor of 1.05 at distances within about 100 km, but it can exceed a factor of 2 at 300 km for short-period GMIMs.
Boore et al. (2022;此后,Bea22)使用Chiou和Youngs(2014)描述了对主区地震动预测模型(GMPM)的调整,以用于目标区域的危害计算;以CY14)为宿主-区域模型。本文包含对Bea22过程的两个修改,用于主机到目标的调整,一个用于源,一个用于非弹性衰减函数。第一个修改是计算Bea22中给出的源调整变量ΔcM的逻辑树分支,假设主机和目标区域应力参数不相关,而不是Bea22中隐含的假设它们完全相关。由于主区应力参数的标准差远小于靶区应力参数的标准差,因此假设应力参数不相关对Bea22实例的影响不大。然而,在未来的一些应用程序中可能不是这样。第二种改进是对主机到目标的非弹性衰减路径调整。Bea22中的调整涉及γ变量的距离无关变化,该变量控制CY14 GMPM中的非弹性衰减速率。本文提出了一种在平差中考虑距离依赖的方法。在距离大于100公里的短周期地面运动强度测量(gims)中需要这种依赖关系,其重要性随着距离的增加而增加。以Bea22中的例子为例,在大约100公里的距离内,用修正后的和先前的γ调整计算的gmm的比率小于约1.05倍,但在300公里的距离内,短周期gmm的比率可以超过2倍。
{"title":"Construction of a Ground-Motion Logic Tree through Host-to-Target Region Adjustments Applied to an Adaptable Ground-Motion Prediction Model: An Addendum","authors":"David M. Boore","doi":"10.1785/0120230143","DOIUrl":"https://doi.org/10.1785/0120230143","url":null,"abstract":"ABSTRACT Boore et al. (2022; hereafter, Bea22) described adjustments to a host-region ground-motion prediction model (GMPM) for use in hazard calculations in a target region, using Chiou and Youngs (2014; hereafter, CY14) as the host-region model. This article contains two modifications to the Bea22 procedures for the host-to-target adjustments, one for the source and one for the anelastic attenuation function. The first modification is to compute logic-tree branches for the source adjustment variable ΔcM given in Bea22 assuming that the host- and target-region stress parameters are uncorrelated, instead of the implicit assumption in Bea22 that they are perfectly correlated. The assumption of uncorrelated stress parameters makes little difference for the example in Bea22 because the standard deviation of the host-region stress parameter is much less than that of the target-region stress parameter. However, this might not be the case in some future applications. The second modification is to the host-to-target anelastic attenuation path adjustment. The adjustment in Bea22 involves a distance-independent change in the γ variable that controls the rate of anelastic attenuation in the CY14 GMPM. This article proposes a method to account for a distance dependence in the adjustment. Such a dependence is needed for short-period ground-motion intensity measures (GMIMs) at distances greater than 100 km, with the importance increasing with distance. For the example in Bea22, the ratio of GMIMs computed with the revised and the previous adjustment to γ is less than about a factor of 1.05 at distances within about 100 km, but it can exceed a factor of 2 at 300 km for short-period GMIMs.","PeriodicalId":9444,"journal":{"name":"Bulletin of the Seismological Society of America","volume":"26 29","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135863318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A Population-Based Performance Evaluation of the ShakeAlert Earthquake Early Warning System for M 9 Megathrust Earthquakes in the Pacific Northwest, U.S.A. 美国太平洋西北地区9级特大逆冲地震ShakeAlert地震预警系统基于人群的性能评价
3区 地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2023-10-31 DOI: 10.1785/0120230055
Mika Thompson, J. Renate Hartog, Erin A. Wirth
ABSTRACT We evaluate the potential performance of the ShakeAlert earthquake early warning system for M 9 megathrust earthquakes in the Pacific Northwest (PNW) using synthetic seismograms from 30 simulated M 9 earthquake scenarios on the Cascadia subduction zone. The timeliness and accuracy of source estimates and effectiveness of ShakeAlert alert contours are evaluated with a station-based alert classification scheme using an alert threshold equal to the target threshold. We develop a population-based alert classification method by aligning a population grid with Voronoi diagrams computed from the station locations for each scenario. Using raster statistics, we estimate the PNW population that would receive timely accurate alerts during an offshore M 9 earthquake. We also examine the range of expected warning times with respect to the spatial distribution of the population. Results show that most of the population in our evaluation region could receive alerts with positive warning times for an alert threshold of modified Mercalli intensity (MMI) III, but that late and missed alerts increase because the alert threshold is increased. An average of just under 60% of the population would be alerted for MMI V prior to the arrival of threshold level shaking. Large regions of late and missed alerts for thresholds MMI IV and V are caused by delays in alert updates, inaccurate FinDer source estimates, and undersized alert contours due to magnitude underestimation. We also investigate an alerting strategy where ShakeAlert sends out an alert to the entire evaluation region when the system detects at least an M 8 earthquake along the coast. Because large magnitude offshore earthquakes are rare in Cascadia, overalerting is most likely to occur from an overestimated M 7+ on the Gorda plate. With appropriate criteria to minimize overalerting, this strategy may eliminate all missed and late alerts except at sites close to the epicenter.
摘要利用卡斯卡迪亚俯冲带30个模拟9级地震情景的合成地震记录,评估了ShakeAlert地震预警系统在太平洋西北地区(PNW) 9级特大逆冲地震中的潜在性能。采用一种基于站点的警报分类方案,评估源估计的及时性和准确性以及ShakeAlert警报轮廓的有效性,该方案使用的警报阈值等于目标阈值。我们开发了一种基于人口的警报分类方法,将人口网格与从每个场景的站点位置计算的Voronoi图对齐。使用栅格统计,我们估计PNW人口将收到及时准确的警报在海上9级地震。我们还研究了相对于人口空间分布的预期预警时间的范围。结果表明,在修正Mercalli强度(MMI) III型预警阈值范围内,评价区大部分人群均能收到正向预警次数的预警,但随着预警阈值的提高,延迟预警和错过预警的情况有所增加。平均不到60%的人口会在阈值震动到来之前收到MMI V警报。阈值MMI IV和V的大面积延迟和错过警报是由警报更新延迟、FinDer源估计不准确以及由于震级低估而导致的警报轮廓过小造成的。我们还研究了一种警报策略,当系统检测到沿海地区至少发生8级地震时,ShakeAlert会向整个评估区域发出警报。由于卡斯卡迪亚很少发生大震级的近海地震,因此对戈达板块的7+级地震的高估很可能导致过度警惕。通过适当的标准来减少过度警报,该策略可以消除所有遗漏和延迟警报,除了靠近震中的站点。
{"title":"A Population-Based Performance Evaluation of the ShakeAlert Earthquake Early Warning System for <i>M</i> 9 Megathrust Earthquakes in the Pacific Northwest, U.S.A.","authors":"Mika Thompson, J. Renate Hartog, Erin A. Wirth","doi":"10.1785/0120230055","DOIUrl":"https://doi.org/10.1785/0120230055","url":null,"abstract":"ABSTRACT We evaluate the potential performance of the ShakeAlert earthquake early warning system for M 9 megathrust earthquakes in the Pacific Northwest (PNW) using synthetic seismograms from 30 simulated M 9 earthquake scenarios on the Cascadia subduction zone. The timeliness and accuracy of source estimates and effectiveness of ShakeAlert alert contours are evaluated with a station-based alert classification scheme using an alert threshold equal to the target threshold. We develop a population-based alert classification method by aligning a population grid with Voronoi diagrams computed from the station locations for each scenario. Using raster statistics, we estimate the PNW population that would receive timely accurate alerts during an offshore M 9 earthquake. We also examine the range of expected warning times with respect to the spatial distribution of the population. Results show that most of the population in our evaluation region could receive alerts with positive warning times for an alert threshold of modified Mercalli intensity (MMI) III, but that late and missed alerts increase because the alert threshold is increased. An average of just under 60% of the population would be alerted for MMI V prior to the arrival of threshold level shaking. Large regions of late and missed alerts for thresholds MMI IV and V are caused by delays in alert updates, inaccurate FinDer source estimates, and undersized alert contours due to magnitude underestimation. We also investigate an alerting strategy where ShakeAlert sends out an alert to the entire evaluation region when the system detects at least an M 8 earthquake along the coast. Because large magnitude offshore earthquakes are rare in Cascadia, overalerting is most likely to occur from an overestimated M 7+ on the Gorda plate. With appropriate criteria to minimize overalerting, this strategy may eliminate all missed and late alerts except at sites close to the epicenter.","PeriodicalId":9444,"journal":{"name":"Bulletin of the Seismological Society of America","volume":"2016 34","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135813996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
New Zealand Fault-Rupture Depth Model v.1.0: A Provisional Estimate of the Maximum Depth of Seismic Rupture on New Zealand’s Active Faults 新西兰断层破裂深度模型v.1.0:新西兰活动断层地震破裂最大深度的临时估计
3区 地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2023-10-27 DOI: 10.1785/0120230166
Susan Ellis, Stephen Bannister, Russ Van Dissen, Donna Eberhart-Phillips, Carolyn Boulton, Martin Reyners, Rob Funnell, Nick Mortimer, Phaedra Upton, Chris Rollins, Hannu Seebeck
ABSTRACT We summarize estimates of the maximum rupture depth on New Zealand’s active faults (“New Zealand Fault-Rupture Depth Model v.1.0”), as used in the New Zealand Community Fault Model v1.0 and as a constraint for the latest revision of the New Zealand National Seismic Hazard Model (NZ NSHM 2022). Rupture depth estimates are based on a combination of two separate model approaches (using different methods and datasets). The first approach uses regional seismicity distribution from a relocated earthquake catalog to calculate the 90% seismicity cutoff depth (D90), representing the seismogenic depth limit. This is multiplied by an overshoot factor representing the dynamic propagation of rupture into the conditional stability zone, and accounting for the difference between regional seismicity depths and the frictional properties of a mature fault zone to arrive at a seismic estimate of the maximum rupture depth. The second approach uses surface heat flow and rock type to compute depths that correspond to the thermal limits of frictional instabilities on seismogenic faults. To arrive at a thermally-based maximum rupture depth, these thermal limits are also multiplied by an overshoot factor. Both the models have depth cutoffs at the Moho and/or subducting slabs. Results indicate the maximum rupture depths between 8 (Taupō volcanic zone) and &gt;30 km (e.g., southwest North Island), strongly correlated with regional thermal gradients. The depths derived from the two methods show broad agreement for most of the North Island and some differences in the South Island. A combined model using weighting based on relative uncertainties is derived and validated using constraints from hypocenter and slip model depths from recent well-instrumented earthquakes. We discuss modifications to the maximum rupture depths estimated here that were undertaken for application within the NZ NSHM 2022. Our research demonstrates the utility of combining seismicity cutoff and thermal stability estimates to assess the down-dip dimensions of future earthquake ruptures.
我们总结了新西兰活动断层的最大破裂深度估计(“新西兰断层破裂深度模型v.1.0”),用于新西兰社区断层模型v1.0,并作为新西兰国家地震危险模型(NZ NSHM 2022)最新修订的约束。破裂深度估计是基于两种独立模型方法的组合(使用不同的方法和数据集)。第一种方法利用重新定位地震目录的区域地震活动性分布来计算90%地震活动性截止深度(D90),代表发震深度极限。再乘以一个超调系数,表示破裂向条件稳定带的动态传播,并考虑区域地震活动深度与成熟断裂带摩擦特性之间的差异,从而得出最大破裂深度的地震估计。第二种方法利用地表热流和岩石类型来计算与发震断层摩擦不稳定性热极限相对应的深度。为了得到基于热的最大破裂深度,这些热极限还要乘以一个超冲系数。这两种模型都在莫霍和/或俯冲板块处有深度界限。结果表明,最大破裂深度在8 km(陶普火山带)~ 30 km(如北岛西南部)之间,与区域热梯度密切相关。两种方法得到的深度在北岛大部分地区显示出广泛的一致性,而在南岛则有一些差异。基于相对不确定性的加权组合模型得到了推导,并使用了最近地震的震源和滑动模型深度的约束条件进行了验证。我们讨论了在新西兰NSHM 2022中应用的最大破裂深度的修改。我们的研究表明,结合地震活动切断和热稳定性估计来评估未来地震破裂的下倾尺寸的效用。
{"title":"New Zealand Fault-Rupture Depth Model v.1.0: A Provisional Estimate of the Maximum Depth of Seismic Rupture on New Zealand’s Active Faults","authors":"Susan Ellis, Stephen Bannister, Russ Van Dissen, Donna Eberhart-Phillips, Carolyn Boulton, Martin Reyners, Rob Funnell, Nick Mortimer, Phaedra Upton, Chris Rollins, Hannu Seebeck","doi":"10.1785/0120230166","DOIUrl":"https://doi.org/10.1785/0120230166","url":null,"abstract":"ABSTRACT We summarize estimates of the maximum rupture depth on New Zealand’s active faults (“New Zealand Fault-Rupture Depth Model v.1.0”), as used in the New Zealand Community Fault Model v1.0 and as a constraint for the latest revision of the New Zealand National Seismic Hazard Model (NZ NSHM 2022). Rupture depth estimates are based on a combination of two separate model approaches (using different methods and datasets). The first approach uses regional seismicity distribution from a relocated earthquake catalog to calculate the 90% seismicity cutoff depth (D90), representing the seismogenic depth limit. This is multiplied by an overshoot factor representing the dynamic propagation of rupture into the conditional stability zone, and accounting for the difference between regional seismicity depths and the frictional properties of a mature fault zone to arrive at a seismic estimate of the maximum rupture depth. The second approach uses surface heat flow and rock type to compute depths that correspond to the thermal limits of frictional instabilities on seismogenic faults. To arrive at a thermally-based maximum rupture depth, these thermal limits are also multiplied by an overshoot factor. Both the models have depth cutoffs at the Moho and/or subducting slabs. Results indicate the maximum rupture depths between 8 (Taupō volcanic zone) and &amp;gt;30 km (e.g., southwest North Island), strongly correlated with regional thermal gradients. The depths derived from the two methods show broad agreement for most of the North Island and some differences in the South Island. A combined model using weighting based on relative uncertainties is derived and validated using constraints from hypocenter and slip model depths from recent well-instrumented earthquakes. We discuss modifications to the maximum rupture depths estimated here that were undertaken for application within the NZ NSHM 2022. Our research demonstrates the utility of combining seismicity cutoff and thermal stability estimates to assess the down-dip dimensions of future earthquake ruptures.","PeriodicalId":9444,"journal":{"name":"Bulletin of the Seismological Society of America","volume":"55 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136233556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
A Seismogenic Slab Source Model for Aotearoa New Zealand 新西兰奥特罗阿的发震板震源模型
3区 地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2023-10-27 DOI: 10.1785/0120230080
Kiran Kumar Singh Thingbaijam, Matt C. Gerstenberger, Chris Rollins, Russ J. Van Dissen, Sepideh J. Rastin, Annemarie Christophersen, John Ristau, Charles A. Williams, Delphine D. Fitzenz, Marco Pagani
Abstract Intraslab seismicity within the Hikurangi and Puysegur subduction zones constitutes &gt;50% of recorded (Mw≥4.0 events) earthquakes in Aotearoa New Zealand. Here, we develop a source model for intraslab seismicity using recently augmented datasets including models of subduction interface geometries, an earthquake catalog, and a regional moment tensor catalog. For the areal zones of uniform seismicity, we consider the whole of each slab, as well as demarcations between shallower (depth ≤40 km) and deeper regions. Thereafter, we evaluate the magnitude–frequency distributions in each zone. To compute smoothed seismicity distributions, we apply a novel quasi-3D approach that involve: (1) delineation of midslab surfaces (defined by regions of maximum earthquake density), (2) orthogonal projections of hypocenters onto the midslab profiles, (3) uniform gridding of 0.1° down-dip on the midslab, and (4) application of smoothing kernel on the projected hypocenters. We also develop a model to characterize the focal mechanisms of the intraslab earthquakes using the regional moment tensor catalog. This model has median strike angles subparallel to subduction trenches and median dip angles ≥60° in both the subduction zones. The distribution of rake angles suggests that the Hikurangi slab has an extensional regime in the shallower parts but a compressional regime in the deeper parts, indicative of slab flexure. In contrast, the Puysegur slab predominantly exhibits a compressional regime.
Hikurangi和Puysegur俯冲带的实验室内地震活动占新西兰Aotearoa记录的地震(Mw≥4.0事件)的50%。在这里,我们利用最近增强的数据集,包括俯冲界面几何模型、地震目录和区域矩张量目录,开发了一个实验室内地震活动性的源模型。对于均匀地震活动的区域,我们考虑了每个板块的整体,以及较浅(深度≤40 km)和较深区域之间的分界线。然后,我们评估了每个区域的震级-频率分布。为了计算平滑的地震活动分布,我们采用了一种新的准三维方法,其中包括:(1)中板表面的描绘(由最大地震密度区域定义),(2)震源在中板剖面上的正交投影,(3)中板上0.1°下倾的均匀网格,以及(4)在投影的震源上应用平滑核。我们还建立了一个利用区域矩张量表来描述岩内地震震源机制的模型。该模型中走向角与俯冲沟近平行,两个俯冲带中倾角均≥60°。前倾角的分布表明,Hikurangi板块浅部为张拉型,深层为挤压型,显示出板块的弯曲性。相比之下,Puysegur板块主要表现为挤压状态。
{"title":"A Seismogenic Slab Source Model for Aotearoa New Zealand","authors":"Kiran Kumar Singh Thingbaijam, Matt C. Gerstenberger, Chris Rollins, Russ J. Van Dissen, Sepideh J. Rastin, Annemarie Christophersen, John Ristau, Charles A. Williams, Delphine D. Fitzenz, Marco Pagani","doi":"10.1785/0120230080","DOIUrl":"https://doi.org/10.1785/0120230080","url":null,"abstract":"Abstract Intraslab seismicity within the Hikurangi and Puysegur subduction zones constitutes &amp;gt;50% of recorded (Mw≥4.0 events) earthquakes in Aotearoa New Zealand. Here, we develop a source model for intraslab seismicity using recently augmented datasets including models of subduction interface geometries, an earthquake catalog, and a regional moment tensor catalog. For the areal zones of uniform seismicity, we consider the whole of each slab, as well as demarcations between shallower (depth ≤40 km) and deeper regions. Thereafter, we evaluate the magnitude–frequency distributions in each zone. To compute smoothed seismicity distributions, we apply a novel quasi-3D approach that involve: (1) delineation of midslab surfaces (defined by regions of maximum earthquake density), (2) orthogonal projections of hypocenters onto the midslab profiles, (3) uniform gridding of 0.1° down-dip on the midslab, and (4) application of smoothing kernel on the projected hypocenters. We also develop a model to characterize the focal mechanisms of the intraslab earthquakes using the regional moment tensor catalog. This model has median strike angles subparallel to subduction trenches and median dip angles ≥60° in both the subduction zones. The distribution of rake angles suggests that the Hikurangi slab has an extensional regime in the shallower parts but a compressional regime in the deeper parts, indicative of slab flexure. In contrast, the Puysegur slab predominantly exhibits a compressional regime.","PeriodicalId":9444,"journal":{"name":"Bulletin of the Seismological Society of America","volume":"178 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136233427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
期刊
Bulletin of the Seismological Society of America
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1