The Experts below are selected from a list of 51294 Experts worldwide ranked by ideXlab platform
Heiner Igel - One of the best experts on this subject based on the ideXlab platform.
-
Recent Advances in Rotational Seismology
Seismological Research Letters, 2009Co-Authors: William H. K. Lee, Heiner Igel, Mihailo D. TrifunacAbstract:Rotational Seismology is an emerging field of study concerned with all aspects of rotational motions induced by earthquakes, explosions, and ambient vibrations. Two recent monographs (Teisseyre et al. 2006; Teisseyre et al. 2008) and a Bulletin of the Seismological Society of America special issue on Rotational Seismology and Engineering Applications (Lee, Celebi et al. 2009) are useful starting points. Rotational Seismology is of interest to a wide range of disciplines, including various branches of Seismology, earthquake engineering, and geodesy, as well as to physicists using Earth-based observatories for detecting gravitational waves generated by astronomical sources, as predicted by Einstein in 1916. Traditionally, only translational ground motions are observed in Seismology. However, we should also measure the three components of rotational motion and the six or more components of strain (Lee, Celebi et al. 2009). We will improve our understanding of the earthquake process (and the complex ground motions it generates) by developing new processing and inversion schemes including the new observables in rotations and strains. In this article we provide a summary of recent activities, some background information, and selected highlights of advances in rotational Seismology and engineering applications. Following Hudnut (2005) on integrating real-time GPS with inertial sensors (including both translation and rotational), W. H. K. Lee (with K. W. Hudnut and J. R. Evans as coordinators) organized a mini-workshop on rotational Seismology on February 16, 2006 (Evans et al. 2007). After the workshop, Evans and Lee contacted other groups active in rotational motions in several countries. An international working group on rotational Seismology (IWGoRS) was then organized to promote investigations of rotational motions and their implications and to share experience, data, software, and results in an open Web-based environment (Todorovska et al. 2008). Anyone can join IWGoRS at http://www.rotational-Seismology.org, subscribe to the mailing list, and contribute …
-
introduction to the special issue on rotational Seismology and engineering applications
Bulletin of the Seismological Society of America, 2009Co-Authors: William H. K. Lee, Mehmet Celebi, Maria I Todorovska, Heiner IgelAbstract:Rotational Seismology is an emerging field for studying all aspects of ro- tational ground motions induced by earthquakes, explosions, and ambient vibrations. It is of interest to a wide range of geophysical disciplines, including strong-motion Seismology, broadband Seismology, earthquake engineering, earthquake physics, seis- mic instrumentation, seismic hazards, seismotectonics, and geodesy, as well as to physicists using Earth-based observatories for detecting gravitational waves generated by astronomical sources (predicted by Einstein in 1916). In this introduction to the BSSA special issue on rotational Seismology and engineering applications, we will include (1) some background information, (2) a summary of the recent events that led to this special issue, and (3) an overview of its 51 papers—27 articles, 11 short notes, 4 reviews, 6 tutorials, and 3 supplementary articles. Our comments on these 51 papers are very brief and give just a hint of what the papers are about. Papers in this special issue demonstrate that earthquake monitoring cannot be limited to measuring only the three components of translational motion. We also need to simultaneously measure the three components of rotational motion and the many components of strains. A golden opportunity to improve our understanding of earth- quakes lies in the near field of large earthquakes (within about 25 km of the earthquake ruptures), where nonlinear rock and soil response influences ground motions in a com- plicated way.
Benoit Mosser - One of the best experts on this subject based on the ideXlab platform.
-
Planetary Seismology
Surveys in Geophysics, 1993Co-Authors: Philippe Lognonné, Benoit MosserAbstract:Since 1969, Seismology has been extended beyond the Earth, and seismic sensors have been placed on the surface of other bodies of the solar system. A Lunar seismic network thus operated for the 8 years after 1969, with up to 4 stations, and detected some 1000 Moonquakes per year. A single seismic station was also operated on the Martian surface for 19 months since 1977. Unfortunately, it did not detect any Marsquakes, but produced useful information for future experiments. Remotesensing seismic experiments using Doppler shift observation have also been applied to Jupiter in the last two years and are beginning to return information on the normal modes. Planetary Seismology is thus now well developed, and will provide increasing information on the structure and dynamics of the planets and bodies of the solar system. In this paper we review the state of the art in planetary Seismology. For the terrestrial planets, we compare the seismic sources, structure and experiments on Earth, Moon and Mars. Such a comparison is useful in evaluating the design of past or future experiments. Results in the Seismology of giant planets are also reviewed, stressing the connection between methods and theory.
William H. K. Lee - One of the best experts on this subject based on the ideXlab platform.
-
Recent Advances in Rotational Seismology
Seismological Research Letters, 2009Co-Authors: William H. K. Lee, Heiner Igel, Mihailo D. TrifunacAbstract:Rotational Seismology is an emerging field of study concerned with all aspects of rotational motions induced by earthquakes, explosions, and ambient vibrations. Two recent monographs (Teisseyre et al. 2006; Teisseyre et al. 2008) and a Bulletin of the Seismological Society of America special issue on Rotational Seismology and Engineering Applications (Lee, Celebi et al. 2009) are useful starting points. Rotational Seismology is of interest to a wide range of disciplines, including various branches of Seismology, earthquake engineering, and geodesy, as well as to physicists using Earth-based observatories for detecting gravitational waves generated by astronomical sources, as predicted by Einstein in 1916. Traditionally, only translational ground motions are observed in Seismology. However, we should also measure the three components of rotational motion and the six or more components of strain (Lee, Celebi et al. 2009). We will improve our understanding of the earthquake process (and the complex ground motions it generates) by developing new processing and inversion schemes including the new observables in rotations and strains. In this article we provide a summary of recent activities, some background information, and selected highlights of advances in rotational Seismology and engineering applications. Following Hudnut (2005) on integrating real-time GPS with inertial sensors (including both translation and rotational), W. H. K. Lee (with K. W. Hudnut and J. R. Evans as coordinators) organized a mini-workshop on rotational Seismology on February 16, 2006 (Evans et al. 2007). After the workshop, Evans and Lee contacted other groups active in rotational motions in several countries. An international working group on rotational Seismology (IWGoRS) was then organized to promote investigations of rotational motions and their implications and to share experience, data, software, and results in an open Web-based environment (Todorovska et al. 2008). Anyone can join IWGoRS at http://www.rotational-Seismology.org, subscribe to the mailing list, and contribute …
-
introduction to the special issue on rotational Seismology and engineering applications
Bulletin of the Seismological Society of America, 2009Co-Authors: William H. K. Lee, Mehmet Celebi, Maria I Todorovska, Heiner IgelAbstract:Rotational Seismology is an emerging field for studying all aspects of ro- tational ground motions induced by earthquakes, explosions, and ambient vibrations. It is of interest to a wide range of geophysical disciplines, including strong-motion Seismology, broadband Seismology, earthquake engineering, earthquake physics, seis- mic instrumentation, seismic hazards, seismotectonics, and geodesy, as well as to physicists using Earth-based observatories for detecting gravitational waves generated by astronomical sources (predicted by Einstein in 1916). In this introduction to the BSSA special issue on rotational Seismology and engineering applications, we will include (1) some background information, (2) a summary of the recent events that led to this special issue, and (3) an overview of its 51 papers—27 articles, 11 short notes, 4 reviews, 6 tutorials, and 3 supplementary articles. Our comments on these 51 papers are very brief and give just a hint of what the papers are about. Papers in this special issue demonstrate that earthquake monitoring cannot be limited to measuring only the three components of translational motion. We also need to simultaneously measure the three components of rotational motion and the many components of strains. A golden opportunity to improve our understanding of earth- quakes lies in the near field of large earthquakes (within about 25 km of the earthquake ruptures), where nonlinear rock and soil response influences ground motions in a com- plicated way.
-
17 - Challenges in Observational Seismology
International Geophysics, 2002Co-Authors: William H. K. LeeAbstract:The ability to collect, process, and analyze earthquake data has been significantly accelerated by advances in electronics, communications, computers, and software. Earthquake Seismology is essentially based on field observations. This chapter provides an overview of the observational aspects of earthquake Seismology, emphasizing on instrumental observations of seismic waves generated by earthquakes. It also discusses the nature of seismic monitoring and some challenges in observational Seismology. Some of the challenges in seismic monitoring for hazard mitigation include—namely, (1) cost issues; (2) integration, reorganization, and data loss; (3) rarity in major earthquakes; and (4) planning, management, and bureaucracy. In addition, seismologists must also be able to achieve stable long-term funding; effective management and execution; and delivery of useful products to the users. Because digital seismic data have become widely available on both local and global scales much more major advances in earthquake Seismology are expected in the near future.
Philippe Lognonné - One of the best experts on this subject based on the ideXlab platform.
-
on deck Seismology lessons from insight for future planetary Seismology
Journal of Geophysical Research, 2020Co-Authors: Mark P Panning, Philippe Lognonné, W T Pike, W B Banerdt, Naomi Murdoch, D Banfield, Constantinos Charalambous, Sharon Kedar, Ralph D Lorenz, A G MarusiakAbstract:Before deploying to the surface of Mars, the short-period (SP) seismometer of the InSight mission operated on deck for a total of 48 hours. This dataset can be used to understand how deck-mounted seismometers can be used in future landed missions to Mars, Europa, and other planetary bodies. While operating on deck, the SP seismometer showed signals comparable to the Viking-2 seismometer near 3 Hz where the sensitivity of the Viking instrument peaked. Wind sensitivity showed similar patterns to the Viking instrument, although amplitudes on InSight were ~80% larger for a given wind velocity. However, during the low wind evening hours the instrument noise levels at frequencies between 0.1 and 1 Hz were comparable to quiet stations on Earth, although deployment to the surface below the Wind and Thermal Shield lowered installation noise by roughly 40 dB in acceleration power. With the observed noise levels and estimated seismicity rates for Mars, detection probability for quakes for a deck-mounted instrument are low enough that up to years of on-deck recordings may be necessary to observe an event. Because the noise is dominated by wind acting on the lander, though, deck-mounted seismometers may be more practical for deployment on airless bodies, and it is important to evaluate the seismicity of the target body and the specific design of the lander. Detection probabilities for operation on Europa reach over 99% for some proposed seismicity models for a similar duration of operation if noise levels are comparable to low-wind time periods on Mars.
-
Planetary Seismology
Surveys in Geophysics, 1993Co-Authors: Philippe Lognonné, Benoit MosserAbstract:Since 1969, Seismology has been extended beyond the Earth, and seismic sensors have been placed on the surface of other bodies of the solar system. A Lunar seismic network thus operated for the 8 years after 1969, with up to 4 stations, and detected some 1000 Moonquakes per year. A single seismic station was also operated on the Martian surface for 19 months since 1977. Unfortunately, it did not detect any Marsquakes, but produced useful information for future experiments. Remotesensing seismic experiments using Doppler shift observation have also been applied to Jupiter in the last two years and are beginning to return information on the normal modes. Planetary Seismology is thus now well developed, and will provide increasing information on the structure and dynamics of the planets and bodies of the solar system. In this paper we review the state of the art in planetary Seismology. For the terrestrial planets, we compare the seismic sources, structure and experiments on Earth, Moon and Mars. Such a comparison is useful in evaluating the design of past or future experiments. Results in the Seismology of giant planets are also reviewed, stressing the connection between methods and theory.
Peter Gerstoft - One of the best experts on this subject based on the ideXlab platform.
-
machine learning in Seismology turning data into insights
Seismological Research Letters, 2019Co-Authors: Qingkai Kong, Daniel T Trugman, Zachary E Ross, Michael J Bianco, Brendan J Meade, Peter GerstoftAbstract:This article provides an overview of current applications of machine learning (ML) in Seismology. ML techniques are becoming increasingly widespread in Seismology, with applications ranging from identifying unseen signals and patterns to extracting features that might improve our physical understanding. The survey of the applications in Seismology presented here serves as a catalyst for further use of ML. Five research areas in Seismology are surveyed in which ML classification, regression, clustering algorithms show promise: earthquake detection and phase picking, earthquake early warning (EEW), ground‐motion prediction, seismic tomography, and earthquake geodesy. We conclude by discussing the need for a hybrid approach combining data‐driven ML with traditional physical modeling.
