These are the defined scientific sessions for the LACSC 4th Assembly.

CodeMain ConvenerInstitutionSession NameSession DescriptionAdditional Conveners
LACSC-1Christa von Hillebrandt-AndradeManager US NWS Caribbean Tsunami Warning Program, Puerto RicoTsunamis in Latin America and the Caribbean: Recent Developments and Plans for the FutureLatin America and the Caribbean have witnessed over the past centuries the devastating impacts tsunamis can have along its coastlines. Recent tsunami events have demonstrated that the risk and vulnerability from tsunami hazards continues to grow with expanding coastal populations and infrastructure. While the understanding and warning capabilities have significantly increased over the last decades, the catastrophic 2004 Indian Ocean and 2011 Japan events as well as the more recent 2018 Sulawesi and Krakatau tsunamis continue to highlight that even more advances are required. This session provides a broad forum for trans-disciplinary studies and invites contributions from all areas of tsunami science including: monitoring and detection; forecast and warning procedures; investigation and hindcasting of past events; mitigation, preparedness, response and recovery strategies; and hazard and risk studies from tsunamis generated by earthquakes, landslides, volcanic eruptions, meteorological phenomena, and meteorite impacts. With the upcoming UN Decade on Ocean Science for Sustainable Development (2021-2030) and the proposal of the global tsunami community, "Taking on the World’s Most Dangerous Waves", we also encourage talks focused on the future of tsunami science within the framework of the UN Sustainable Development Goals and policy interface. Session supported by IAPSO.• Silvia Chacon - National Univ. of Costa Rica, Costa Rica
• Lt. Commander Giorgio De La Torre - Oceanographic Inst., Ecuadorian Navy (INOCAR), Guayaquil, Ecuador
• Wilfried Strauch - INETER/CEPREDENAC, Nicaragua
• Sergio Barrientos - University of Chile, Santiago, Chile
LACSC-2Dmitry StorchakInternational Seismological Centre, UKAdvances in Seismic Network OperationsAdvances in technology and growing number of seismic stations and networks have made it possible to improve earthquake monitoring in the Latin America and the Caribbean region. This session welcomes overviews of national permanent seismic networks and temporary deployments and related research. The session also covers contributions from all aspects of seismic network operations such as: site selection, equipment installation, station geometry, rapid and routine seismic event detection, monitoring and notification, public communication of seismic information, earthquake catalogues, as well as acquisition, processing, archiving, and dissemination of seismic waveforms and parametric datasets and products. Contributions on methods and procedures for improved earthquake location, source, and magnitude determination from national and international seismic networks are encouraged.• Marcelo Assumpção - Univ. de Sao Paulo, Brazil
LACSC-3Hans Agurto-DetzelKarlsruhe Inst. of Technology, GermanySubduction Zone I: Forearc Processes along Latin AmericaSubduction zones in Latin America, including those in Central and South America, present a great diversity of seismotectonic phenomena. The forearc, in particular, concentrates a wide range of along-strike segmentation, deformation regime, structural characteristics of both the subducting and overriding plates, and slip behavior. Recent years have seen an increase of onshore/offshore experiments tackling issues such as fluid content and interaction between seismic and aseismic slip processes. Moreover, it is now common to observe a great diversity of slip behavior along the interface, including slow slip events, tremors, repeating earthquakes, and earthquake swarms. In this session, we invite contributions studying the variety of seismotectonic processes that take place in the subduction forearc, and their effects on permanent and elastic deformation along the margin. We welcome both theoretical and observational studies, including experiments using passive and active seismology, and geodesy.• Rafael Almeida - San Diego, USA
• Sergio Ruiz - Univ. of Chile
LACSC-4Susan BeckArizona Univ.Subduction Zone II: Backarc ProcessesSubduction is one of the most dynamic processes on the Earth where the largest earthquakes occur, where magma is produced and erupted in volcanic arcs, where material (including water) is recycled into the interior of the Earth and where continental crust is both created and destroyed. The Mexico, Central America and South America convergent margins have a range of processes in the down-going and over-riding plates that have built high mountains and cause significant backarc deformation both seismic and aseismic. In addition, intermediate depth earthquakes, shallow backarc and cratonic earthquakes are often very damaging and less well studied. Improvements in seismic imaging and earthquake sources studies have led to a wealth of new knowledge of the convergent margin processes including both flat and normal slab subduction. We invite abstracts on a broad range of processes from the volcanic and magmatic processes to backarc and cratonic deformation to flat slab subduction to deep subduction and mantle processes in Latin America and beyond.• Patricia Alvarado - UNSJ, Argentina
• Lepolt Linkimer - UCR, Costa Rica
LACSC-5Steve KirbyUSGSIntraslab Earthquakes: Insights into their physical mechanisms from seismological observations and knowledge of slab evolution during descentIntraslab earthquakes along the western margins of Latin America have led to many especially destructive earthquakes during the instrumental era of seismological investigation. Understanding such earthquakes in descending oceanic lithosphere is especially challenging since the structures of such seismogenic faults is typically not accessible by direct inspection and since a host of complex physical processes are expected to occur during slab descent. Contributions to this session that provide seismological information and analysis of such events are welcome.• Germán Prieto - UNAL, Colombia
LACSC-6Juan Carlos Montalvo-ArrietaUNAM, MexicoSeismicity in Interiors of the ContinentsThe recent improvement of seismic networks at continental interiors has demonstrated the need for a better understanding the seismic processes in intraplate and midplate regions. Although the return periods for earthquakes with M > 6 may be greater than 500 years, major earthquakes in the past caused damage, and have the potential for serious human losses if they were to occur again. In many cases, the absence of seismic hazard studies generates the belief in the society and authorities that earthquakes do not occur, so urban developments are made without adequate building codes. In addition, the causes of intraplate seismicity are still a matter of considerable debate, including the disputed strain accumulation/release model. Therefore, it is necessary to review the advances in seismology, experiences, and challenges for the populations located in this context, especially in Latin America and the Caribbean region. Contributions related to seismotectonics, site effects, macroseismic intensities, hazard estimates in low-strain regions, paleoseismicity, and seismological networks are welcome.• Xyoli Pérez-Campos - UNAM, Mexico
• Marcelo Assumpção - Univ. de Sao Paulo, Brazil
LACSC-7Aaron A. VelascoThe University of Texas at El PasoEarthquake Dynamics and InteractionsA variety of mechanisms have been invoked to explain the underlying physics driving earthquake nucleation and slip, including co-seismic static and dynamic stress changes, aseismic deformation, fluid-driven processes caused by underground injection of fluids, and other general fluctuations in background stress states. What is less certain is how or if this wide range of processes may be linked on multiple spatial and temporal scales, and by studying these interactions, reveal a fundamental earthquake rupture process. In this session, we seek studies ranging from the theoretical to the observational that may address: (1) To what extent can the potential for static and dynamic triggering be differentiated, and is that difference relevant? (2) What are the mechanisms and time scales by which medium changes (changes in damage profile, permeability/porosity, or seismic velocity) operate on and modulate background seismicity? (3) What changes in stress conditions stored on ancient faults are needed to trigger an earthquake from external perturbations (i.e., fluid injection), and could all faults reactivate with local stress changes? (4) What are the frictional conditions that govern the final size of an earthquake and can these conditions be observationally gleaned beforehand? and (5) Are there paradigmatic or computational blind spots that must be addressed before progress can be made in these areas?• Stephen Hernandez - IG-EPN, Ecuador
LACSC-8Steve MyersLLNL, USSeismic Tomography and 3D Models for Earthquake LocationsUse of an accurate three-dimensional (3D) model has been shown to improve the prediction of seismic observables, such as phase travel times that are used to locate seismic events. Three-dimensional models are not commonly used in routine seismic analysis because an accurate model may not be available and computational demands may preclude the use of a 3D model on many operational systems. Nonetheless, development of 3D models is becoming more common due to improved data and the maturation of tomographic methods and codes. Also, new computational methods and upgrades to operational computer systems area making routine use of 3D models possible. This session encourages all abstract submissions that show improvements in predicted seismic-phase travel times, amplitudes, and seismic waveforms with the application of tomography inversions that solve for 3D earth velocity models, including case studies that illustrate their effectiveness in conventional seismic analysis.• Ronnie Quintero - UNA CR
LACSC-9Ben BrooksUSGSEarly Warning Systems for Earthquakes and Other Natural Phenomena: Achievements and Future PerspectivesRecent technological innovations in instrumentation, telecommunications and software development have encouraged the development of early warning systems of various natural phenomena in many countries and under very different geological and geographic conditions. Today, several early warning systems exist to advise the population of impending earthquakes, tsunamis and hydrometeorological phenomena. In many cases, new systems are being planned and installed. The session is designed for scientists and engineers of existing early warning systems to report the performance of their systems, their utilization and to inform of future developments. The session will also serve as a forum to discuss the advantages and limitations of early warning systems as tools for risk reduction in urban centers exposed to natural phenomena. Contributions are welcome on algorithm development, different instrumentation, technological innovations and social use and impact of early warning systems. Of special interest are aspects of Earthquake EWS related to population preparedness for actions during the alarm dissemination.• Gerardo Suárez - UNAM, Mexico
• John Clinton - ETH
• Marino Protti - OVSICORI-UNA
LACSC-10Pierre LacanUNAMCharacterization of Latin America and Caribbean crustal faults based on earthquake geology and paleoseismology approachesGeological investigations provide key inputs in seismotectonic and geodynamic models, as well as seismic hazard analyses. Beside prominent subduction-related events and associated hazards, severe or destructive earthquakes regularly hit South America and the Caribbean region. They cover a wide range of crustal tectonic environments, including interplate transcurrent zones , oblique-collision belts , fold-and-thrust intraplate areas , high-elevation extensional ranges or extensive strike-slip fault zones . The rapid development of the South America and Caribbean countries poses huge challenges to authorities and decision makers where big cities or capitals are set up on top of active faults (e.g. San Salvador, Quito). Geological approaches are very important because they provide insights on the long-term behavior of faults, a keystone of both geodynamic models and seismic hazard studies. Quantitative assessments include geologically recorded slip rates, earthquake time history and magnitude of surface-rupturing paleo-events. Earthquake geology is also the key approach to analyze the fault displacement hazard that could threaten facilities or infrastructures. Therefore, this session encourages contributions in the fields of neotectonics and paleoseismology, such as geomorphology, geophysics, remote sensing, fault trenching, sedimentological and dating techniques, archeological approaches, as well as fault database upgrading and fault-based seismic hazard assessment. • Laurence Audin - IRD, France
• Ramón Zúñiga - UNAM
• Alexandra Alvarado - IG-EPN, Ecuador
LACSC-11Maria Belen BenitoUniv. Politécnica de MadridSeismic Hazard and Risk in Latin America and the CaribbeanLatin America and the Caribbean are seismically heterogeneous regions with complex tectonic settings that make the elaboration of seismic hazard models challenging. The aim of this session is to promote discussion and to encourage participation of those scientists working on different aspects of the seismic hazard model building and calculation process. The main topics for this session are studies focusing on (1) dataset creation and maintenance of ground-motion, seismic, geodesic, tectonic and related information relevant for modeling hazard; (2) describing the PSHA model construction process and workflows; (3) Faults as independent units in zoning models: challenges and possible solutions, (4) Alternatives to the Poisson models for seismicity (5) GMPEs selection and development, (6) geodetic and tectonic constraints on hazard modeling, (7) uncertainties evaluation (8) more general contributions in the PSHA context, (9) application of geospatial technologies in the characterization of exposure, and (10) vulnerability , capacity and fragility models.• Augusto Antonio Gomez Capera - INGV, Milano, Italy
• Mark Petersen - USGS
LACSC-12Fabian BonillaIFSTTAR, FranceSite effects: influence of the local geology on the ground motionIn the last twenty years, dense accelerometer networks have been installed worldwide, and the recorded data persistently show that the local geology can strongly affect the ground motion by amplifying it, increasing its duration, and introducing spatial variability. In certain cases, when the ground motion is strong enough, the material may develop large deformations reducing the media shear modulus, increasing the damping, producing liquefaction and permanent displacements among other things. Concomitantly, numerical simulations of wave propagation have exponentially increased in the last years, mainly due to the larger computer power and the development of greatly optimized codes. In spite of these advances, there are still some problems to be solved, and one of them is the media characterization (velocity model at different scales). We lack a detailed description of the shallow geology, the geometry of the local structures, and the rheology of the material when strong motion could trigger nonlinear soil response. The combination of these processes influences the resulting ground motion at the Earth's surface, and more importantly, its uncertainty. This session aims to present studies related to these research subjects, from field data analyses (site response studies), numerical simulations, case studies from recent events, high frequency attenuation (kappa), microzonation studies and secondary effects of earthquake shaking such as liquefaction and landslides.No additional conveners.
LACSC-13Patricia A. MothesIG-EPN, EcuadorIntegrating Geodesy and Seismology to better understand Earthquakes and Fault behaviorGeodetic techniques (GNSS, InSAR, LIDAR, Optical image matching etc.) complement seismological investigations in tectonically active areas. For studies of large earthquake, suites of precise geodetic observations can reveal rupture length, lateral and vertical surface offsets, and possible stress translation to neighboring fault(s). Geodesy also provides insights into the deformation occurring before earthquakes, helping to better anticipate large events. With geodetic techniques we can recognize locked areas of fault zones and aseismic creeping patches which may release stress prior to a large earthquake and could also act as a barrier to rupture propagation. Patterns of slow slip events (SSEs) may be key to anticipate zones of future rupture. Examples exist of identifying pre-rupture deformation patterns and associated seismicity before large earthquakes, like in N. Chile (2014), Mw=8.1 and at Nicoya Mw=7.6. On the other hand, real-time GPS measurements may aid in discerning in 10-25 seconds of observation, the magnitude outcome of an earthquake in process. Finally, continental/sub-continental scale GPS results are vital for discerning geodynamic trends over vast areas and also fault kinematics. Space borne geodesy imaging techniques improves understanding of surface deformation, past and present. Given these successes in incorporating geodetic techniques, we solicit contributions which demonstrate the strong coupling of seismology and geodesy.No additional conveners.
LACSC-14Victor HuérfanoPuerto Rico Seismic Network / UPRMTectonics, Seismicity and recent events in the Northeastern CaribbeanGreater and Lesser Antilles are located at the active plate boundary between the North American and the Caribbean plate. Large magnitude Earthquakes and destructive tsunamis are mostly caused by the convergence and interactions of those plates. In the 20th century there have been several large magnitude and destructive earthquakes 7.4 in 1918; 7.6 in 1943; M 8.0 in 1946 (Puerto Rico and Hispaniola). The most recent event that cause damages and destruction to our islands happens as recent as the 07/January/2020 (M6.4). Large tsunamis have also hit our islands killing many people. All of the known causes of tsunamis are present in the Caribbean (earthquakes, submarine/subaerial landslides, submarine volcanoes, subaerial pyroclastic flows into the ocean, and major teletsunamis). The exposure and associate risk are increased because of its high population density and extensive development near the coast, all the northeastern Caribbean has a significant risk for earthquakes and tsunamis; and that is the goal of this section to have a forum to present the actuality of research and activity in this very sensitive part of the Caribbean. • Jay Pulliam - Baylor University
• Lloyd Lynch - Univ. West Indies
• Eugenio Polanco Rivera - Centro Nacional de Sismología, Universidad Autónoma de Santo Domingo
LACSC-15Carlos Alberto VargasUniv. Nacional de ColombiaAnthropogenic SeismicitySeismological instrumentation is nowadays intensely deployed for monitoring industrial activities, such as exploitation of mines, development of oil and geothermal fields, loading, and unloading of dams as a consequence of climatic change, and construction of extensive infrastructure. Other physical variables, such as the pore pressure, and the geometry and depth of the basement, also seem to be critical to establishing causality and the eventual control of anthropogenic seismicity. Recent work in oil fields where secondary recovery, as well as fracking techniques, are used link the pore pressure promoted by the over-injection of waste fluids as a key element that controls that seismicity. Additionally, the configuration of the sedimentary basins where these fluids will end and the cyclic processes of loading and unloading look to be decisive for the proper exercise of certain industrial practices. In the framework of oil and gas and unconventional, apart from pore pressure mechanisms, fault re-activation and poro-elastic stress change are discussed. Apart from seismic moment release, aseismic processes may play a significant role. Therefore, we welcome contributions on remote strain measurements via satellite that capture the hazard of possible creeping faults.• Aderson Nascimento - UFRN, Brazil
• Arno Zang - GFZ, Germany
LACSC-16Hugo YepesIG-EPN, EcuadorEarthquakes through History in Latin America and the CaribbeanSince colonial times, earthquakes have been responsible for hundreds of thousands of deaths and incalculable damage in the Latin American and the Caribbean. Lima-Callao 1746, Riobamba 1797, Caracas 1812, Ibarra 1868, Chillan 1939, San Juan 1944, Chimbote 1970, Managua 1972, Guatemala 1976, Ciudad de Mexico 1985, Armenia 1999, Port-au-Prince 2010, among others, are examples for devastating earthquakes in Latin-American and Caribbean cities. Reconstructing past earthquakes helps us to understand seismic sources, site effects and construction vulnerability. It could also be really valuable in contributing for the comprehension of the influence of these natural events in the progress or stalling of our cities and even nations. We encourage seismologists, risk scientists, emergency managers, city planners, historians and chroniclers to contribute to the understanding of historic temblors from the perspective of earthquake, history and resilience sciences.• Gerardo Suárez - UNAM, Mexico
LACSC-17Xyoli Pérez CamposUNAM, MexicoHistorical seismograms: their preservation and useThe instrumental record of the world seismicity covers today, about a century since the first modern mechanical seismographs began to routinely operate. During the first half of the XX century, most of this seismicity has been recorded on smoked-paper and ink-on-paper seismograms. These records preserve highly valuable and unique seismological information, allowing us to expand in time our knowledge of the seismic behavior of many regions in the world. This historical information is complemented with many different related documentations like logbooks, official protocols and accounting books, generated at these seismological observatories. The preservation of this priceless information is an urgent necessity due to the continuous deterioration of the physical media in which this data is imprinted before they further deteriorate and possibly get partially or entirely lost. Techniques and methodologies for preservation and use of such data, along with their scientific use, are essential aspects for advancing our understanding of the past, the current and future seismicity. This session welcomes contributions on technical and other related methodologies/techniques for searching, locating, assessing, preserving and disseminating historical seismograms, as well as those related with the state of the art scientific methodologies for their analysis and use, to advance our understanding of the historical seismicity.• Luis Rivera - Strasbourg
• Miguel Ángel Santoyo García Galiano - UNAM, Mexico
LACSC-18José Augusto CasasServ. Geol. y Minero Argentino, SEGEMARSeismic Ambient Noise: Applications, Interpretations and TheorySeismic Ambient Noise is a rich source of information for studying the Earth's structure at various depths, understanding its dynamics, and the interaction between the solid Earth, the atmosphere, and the ocean. Ambient Noise studies can provide insights to the dynamics of volcanoes, atmospheric phenomena, and other environmental processes. We invite presentations from a wide range of topics in Ambient Noise Seismology concerning multi-scale applications, from local to regional, including crustal structure, subsurface monitoring, underlying volcano structure/dynamics and basin characterization. This session also covers methods for analyzing data recorded by single stations, pairs and arrays of seismic stations and time varying signals. Novel ideas for harnessing big data, using full wavefield, estimating ground motion, and understanding the characteristics of the seismic noise sources are all welcome in this session. We also invite contributions on theory, computational methods and applications for monitoring and imaging in order to get new insights on the dynamics of faults, volcanoes, groundwater and other processes.No additional conveners.
LACSC-19Ronnie QuinteroUNA CRSeismic SwarmsMany seismic 'swarms' occur all over the world, many of them close to volcanoes. Knowing the volcanic or tectonic nature of earthquake series that occur close to an active volcano is fundamental for volcano-tectonic hazard assessment. But how to distinguish how a swarm is tectonic or volcanic? This is the purpose of this session by the presentation of many cases of swarms or earthquakes series both tectonic and volcanic.No additional conveners.
LACSC-20Mario RuizIG-EPN, EcuadorVolcano seismology: new approaches in monitoring and interpretationSeismology on volcanoes requires special consideration due to the fact that the source mechanisms as well as wave propagation effects are significantly different from conventional tectonic earthquakes. Hence, seismic monitoring of active and dormant volcanoes remains the key element of any monitoring program undertaken by volcano observatories or research institutions. Major advances have been made in the last years allowing us to identify several categories of seismic events and interpret them in terms of different magmatic or tectonic processes encountered on a volcano. Attempts based on multi-disciplinary methodologies turned out to be particularly successful. This session is dedicated to latest developments in volcano seismic monitoring techniques, as well as the interpretation and modelling methodology in a wider volcanological context. We invite contributions for both oral and poster presentations that deal with any aspects relevant to seismic monitoring, new methodologies as well as case studies from a variety of volcanic settings in South America and the Caribbean. This includes advances in instrumentation, such as the use of fibre-optical cables and Machine Learning to automate and improve the identification and classification in volcano monitoring.• Jurgen Neuberg - School of Earth & Environment, Leeds University
LACSC-21Hugo D. OrtizUniv of California, Santa BarbaraInfrasound studies in Latin America and the CaribbeanA wide array of natural and anthropogenic processes leads to the generation of infrasound waves (atmospheric sound with frequencies below 20 Hz). In addition to volcanoes, sources of infrasound include earthquakes, mass-wasting events, bolides, ocean wave-wave interactions, lightning, hurricanes, tornadoes, wind flow over mountains, glacier calving, auroras, and many other sources. To advance seismo-acoustics research, various experiments and projects have been performed in Latin America and the Caribbean. For instance, the International Monitoring System has been growing progressively since 2002 and has complemented local and regional deployments carried out by volcano observatories and universities. With the growing infrasound capabilities in the region, we invite submissions that use infrasound to quantify source mechanisms and atmospheric dynamics, as well as explore new algorithms that enhance detection and signal distinction. We will give special attention to studies that aim to improve our understanding of volcanic processes.• Robin Matoza - UC Santa Barbara
• Alejandra Arciniega - UNAM, Mexico
• Stephen Hernandez - IG-EPN, Ecuador
LACSC-22Juan AnzietaSimon Fraser UniversityMachine Learning applications in SeismologyContinuous advancements in instrumentation make the presence of seismic sensors increasingly prevalent in a variety of geodynamic settings. This is particularly true in regions where costs were once prohibitively expensive, such as Latin America. The resulting increase in both the quality and quantity of the signals can simultaneously expand our modeling capabilities while also introducing new computational challenges. Machine learning techniques can potentially bridge this gap by accelerating the processing of large data sets in addition to extracting new insights from the data. We invite the participants of this session to share techniques and experiences in the application of machine learning to seismological research. Problems addressed may include, but are not limited to, automatic event and phase picking, supervised (robust automatic labeling) or unsupervised (identification of families or patterns through clustering) classification of signals, improvements in modeling and digital signal processing, assessment of activity level, and identification of precursory activity in different settings such as subduction zones, volcanoes, active faults or similar.No additional conveners.
LACSC-23Marcelo Assumpção Univ. de Sao Paulo, BrazilGeneral ContributionsPapers on all topics of Seismology, not covered by other sessions, are welcome . This includes seismicity and Earth's structure outside Latin America.• Xyoli Pérez-Campos - UNAM, Mexico