The Seismic Record最新文献_第3页

Direction Estimates for Short-Period P-Waves on Three-Component Stations and Arrays 三分量台站和阵列上短周期p波方向估计

The Seismic Record Pub Date : 2023-10-01 DOI: 10.1785/0320230036

Steven J. Gibbons

{"title":"Direction Estimates for Short-Period <i>P</i>-Waves on Three-Component Stations and Arrays","authors":"Steven J. Gibbons","doi":"10.1785/0320230036","DOIUrl":"https://doi.org/10.1785/0320230036","url":null,"abstract":"Abstract P-arrival backazimuth estimates can be crucial in locating poorly constrained seismic events. Correlating short windows of the vertical waveform with corresponding windows of the radial rotation for different backazimuths can provide estimates, but these are often uncertain and biased due to skewness in the Z–R correlation functions. Assessing how well cosine curves centered on different backazimuths match the Z–R correlation functions provides more reliable estimates that depend less upon the time-window used. Stacking best-fit-cosine curves from neighboring three-component stations improves stability further in a form of array-processing that does not require coherence between the waveforms themselves. We demonstrate for recordings of North Korean nuclear tests at the Pilbara 3C array in Australia that the biases in the Z–R correlation functions vary greatly between adjacent stations. This bias is reduced both by the cosine curve fitting and stacking operations. We advocate obtaining backazimuth estimates for all P arrivals at three-component stations globally. This could improve phase association and event location, identify sensor orientation problems, and provide baseline backazimuth corrections and uncertainty estimates. We propose two benchmark datasets for developing, documenting, and comparing backazimuth estimation algorithms and codes. All the data and code used to generate the results presented here are open.","PeriodicalId":273018,"journal":{"name":"The Seismic Record","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136248068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

How Good Is Your Location? Comparing and Understanding the Uncertainties in Location for the 1993 Rock Valley Sequence 你的位置有多好?1993年岩谷序列定位不确定性的比较与认识

The Seismic Record Pub Date : 2023-10-01 DOI: 10.1785/0320230025

Moira L. Pyle, Ting Chen, Leiph Preston, Michelle Scalise, Cleat Zeiler, Kenneth D. Smith

{"title":"How Good Is Your Location? Comparing and Understanding the Uncertainties in Location for the 1993 Rock Valley Sequence","authors":"Moira L. Pyle, Ting Chen, Leiph Preston, Michelle Scalise, Cleat Zeiler, Kenneth D. Smith","doi":"10.1785/0320230025","DOIUrl":"https://doi.org/10.1785/0320230025","url":null,"abstract":"Abstract Accurate event locations are important for many endeavors in seismology, and understanding the factors that contribute to uncertainties in those locations is complex. In this article, we present a case study that takes an in-depth look at the accuracy and precision possible for locating nine shallow earthquakes in the Rock Valley fault zone in southern Nevada. These events are targeted by the Rock Valley Direct Comparison phase of the Source Physics Experiment, as candidates for the colocation of a chemical explosion with an earthquake hypocenter to directly compare earthquake and explosion sources. For this comparison, it is necessary to determine earthquake hypocenters as accurately as possible so that different source types have nearly identical locations. Our investigations include uncertainty analysis from different sets of phase arrivals, stations, velocity models, and location algorithms. For a common set of phase arrivals and stations, we find that epicentral locations from different combinations of velocity models and algorithms are within 600 m of one another in most cases. Event depths exhibit greater uncertainties, but focusing on the S-P times at the nearest station allows for estimates within approximately 500 m.","PeriodicalId":273018,"journal":{"name":"The Seismic Record","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134935742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The 1886 Charleston, South Carolina, Earthquake: Relic Railroad Offset Reveals Rupture 1886年南卡罗来纳州查尔斯顿地震:遗迹铁路偏移显示断裂

The Seismic Record Pub Date : 2023-10-01 DOI: 10.1785/0320230022

Roger Bilham, Susan E. Hough

引用次数: 0

Evaluating a Prospective Fault-Based Stress-Transfer Forecast for the M 7.9 Wenchuan Earthquake Region, 15 Years Later 汶川7.9级地震15年后断层应力传递预测方法评价

The Seismic Record Pub Date : 2023-07-01 DOI: 10.1785/0320230021

T. Parsons, C. Ji, E. Kirby

{"title":"Evaluating a Prospective Fault-Based Stress-Transfer Forecast for the M 7.9 Wenchuan Earthquake Region, 15 Years Later","authors":"T. Parsons, C. Ji, E. Kirby","doi":"10.1785/0320230021","DOIUrl":"https://doi.org/10.1785/0320230021","url":null,"abstract":"\u0000 Four days after the 12 May 2008 M 7.9 Wenchuan earthquake struck the Sichuan region of China, we submitted a prospective earthquake forecast based on transfer of stress from the mainshock onto significant faults crossing through populated areas. We identified where the largest aftershocks were likely to occur that could cause loss of life. We returned the revised article to the journal on 5 June 2008, marking the last day of our observation period. The primary testable features are locations and focal mechanisms of larger (M ≥ 4.5) earthquakes; did these events happen on or very near the faults we said they would? Did they have the same strikes, dips, and rakes as the faults we modeled? In retrospect, is the stress transfer method consistent with all M ≥ 4.5 earthquakes that occurred? We find all but one M ≥ 4.5 aftershock with known focal mechanisms located on stress-increased faults, and their focal mechanism parameters overlap with geological characteristics we used in making calculations. Six of the seven lethal M > 4.5 earthquakes that occurred in the region since 5 June 2008 were located on stress-increased faults, with the lone exception triggered by hydraulic fracturing.","PeriodicalId":273018,"journal":{"name":"The Seismic Record","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126484498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comment on “Multievent Explosive Seismic Source for the 2022 Mw 6.3 Hunga Tonga Submarine Volcanic Eruption” by Julien Thurin, Carl Tape, and Ryan Modrak 对Julien Thurin, Carl Tape和Ryan Modrak撰写的《2022 Mw 6.3 Hunga Tonga海底火山喷发的多事件爆炸震源》的评论

The Seismic Record Pub Date : 2023-07-01 DOI: 10.1785/0320230003

F. Pollitz, Ricardo Garza‐Girón, T. Lay

引用次数: 1

Spatially Consistent Small-Scale Stress Heterogeneity Revealed by the 2008 Mogul, Nevada, Earthquakes 2008年内华达州莫卧儿地震揭示的空间一致的小尺度应力异质性

The Seismic Record Pub Date : 2023-07-01 DOI: 10.1785/0320230026

Christine J. Ruhl, Rachel E. Abercrombie, Peter M. Shearer

引用次数: 0

Estimating the Magnitude of Completeness of Earthquake Catalogs Using a Simple Random Variable Transformation 用一个简单的随机变量变换估计地震表的完备程度

The Seismic Record Pub Date : 2023-07-01 DOI: 10.1785/0320230017

M. Taroni

引用次数: 1

Characterizing and Locating Seismic Tremor during the 2022 Eruption of Mauna Loa Volcano, Hawai’i, with Network Covariance 基于网络协方差的2022年夏威夷莫纳罗亚火山喷发地震震动特征与定位

The Seismic Record Pub Date : 2023-07-01 DOI: 10.1785/0320230020

S. Maher, P. Dawson, A. Hotovec-Ellis, W. Thelen, A. Jolly, N. Bennington, Jefferson C. Chang, P. Dotray

{"title":"Characterizing and Locating Seismic Tremor during the 2022 Eruption of Mauna Loa Volcano, Hawai’i, with Network Covariance","authors":"S. Maher, P. Dawson, A. Hotovec-Ellis, W. Thelen, A. Jolly, N. Bennington, Jefferson C. Chang, P. Dotray","doi":"10.1785/0320230020","DOIUrl":"https://doi.org/10.1785/0320230020","url":null,"abstract":"\u0000 The 2022 eruption of Mauna Loa Volcano, Hawai’i, was accompanied by continuous seismic tremor that began about 30 min before and ended several days after the eruption. We characterize the amplitude history and frequency content of the tremor, and we use a network covariance-based method to estimate its source location. The tremor exhibits multiple narrow spectral peaks between 1 and 3 Hz, and its amplitude varies through time in a spasmodic manner. Our location results track a northeast migration of shallow sources through the summit region in the first few hours of the eruption. For the remainder of the eruption, source locations cluster in the vicinity of the erupting vent in the northeast rift zone. We attribute the tremor source to gas dynamics in the upper reaches of a basaltic dike. However, limitations in instrumentation and knowledge of the subsurface velocity structure may preclude an assessment of the source mechanism. Our results illustrate the value of characterizing and locating tremor for tracking magma movement, and demonstrate a use for dense and calibrated seismic instrumentation on active volcanoes. The location method we use requires substantial parameter testing, reflecting the potential benefit of developing more flexible approaches toward real-time automated assessment of tremor at volcanoes.","PeriodicalId":273018,"journal":{"name":"The Seismic Record","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123982912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Tracking Local Sea Ice Extent in the Beaufort Sea Using Distributed Acoustic Sensing and Machine Learning 利用分布式声学传感和机器学习跟踪波弗特海局部海冰范围

The Seismic Record Pub Date : 2023-07-01 DOI: 10.1785/0320230019

A. P. Peña Castro, B. Schmandt, M. Baker, R. Abbott

引用次数: 1

Hosgri Fault Transpressional Slip Rates Reproduce Observed Central California Coast Uplift Rates 霍斯格里断层向外滑动速率再现观测到的加利福尼亚中部海岸隆升速率

The Seismic Record Pub Date : 2023-07-01 DOI: 10.1785/0320220047

D. O’Connell, Jamey Turner

{"title":"Hosgri Fault Transpressional Slip Rates Reproduce Observed Central California Coast Uplift Rates","authors":"D. O’Connell, Jamey Turner","doi":"10.1785/0320220047","DOIUrl":"https://doi.org/10.1785/0320220047","url":null,"abstract":"\u0000 Coastal uplift is a common feature of Pacific Rim tectonic deformation. The 1989 Mw 7.0 Loma Prieta earthquake illustrated that reverse-oblique slip on a transpressive segment of the predominantly horizontal slip San Andreas transform fault produces coastal uplift. In west-central California the 400 km long San Gregorio-Hosgri coastal fault system of near-vertical to steeply northeast-dipping, reverse-oblique, dextral strike-slip faults also contribute to coastal uplift. Published southern Hosgri fault dextral slip rates are ∼4× reverse rates. Viscoelastic deformation modeling using published transpressional slip rates along the southern Hosgri fault reproduces observed emergent marine terrace uplift rates, offshore Hosgri fault deformation morphology, and crustal structure from San Luis Obispo Bay to Estero Bay. Our coastal uplift rate modeling is constrained by a unique combination of measurements: (1) offshore reverse- and strike-slip Hosgri fault zone (HFZ) slip rates, and (2) ≤125 ka onshore emergent terrace uplift rates adjacent to the HFZ. The previously proposed conceptual rigid block models of the southern central California coast (CCC) invoke local onshore thrust or reverse faults to explain coastal uplift. Observed transpressional offshore Hosgri fault deformation rates alone rigorously reproduce observed coastal uplift rates and crustal structure along the southern CCC.","PeriodicalId":273018,"journal":{"name":"The Seismic Record","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130305707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0