Chile is a long and narrow country whose continental coastline stretches for more than 6,400 km, home to diverse ecosystems and remarkable geological structures. Its territory lies within the Pacific Ring of Fire, a region of intense seismic and volcanic activity driven by the constant movement of Earth’s fragments (tectonic plates), making it one of the most seismically active places on the planet.
A Mystery Beneath the Ocean Off Our Coast
Bajo el océano Pacífico frente a la costa chilena, se esconde una estructura tan imponente como poco conocida: el Ridge de Juan Fernández. This submarine mountain chain, approximately 800 km long,, rises thousands of meters from the ocean floor,, with its highest peaks forming the Juan Fernández Archipielago Today, the ridge is subducting beneath the South American continent as a result of plate convergence, directly off the coast of the Valparaíso Region,where significant seismic activity of varying magnitudes is recorded..
There is a hypothesis that the ridge may influence how large earthquake ruptures propagate off the coast of the Valparaíso Region, possibly acting as a natural barrier. To evaluate ideas like this, it is essential to study in detail what occurs in its surrounding environment.
In this context, the analysis of microseismicity, low-magnitude events ( << 3) that are not detectable by conventional seismic networks, is key for understanding the region’s active geodynamic processes. These small earthquakes allow researchers to examine how the Earth’s crust evolves over time, how energy accumulates, and how it may be released in larger events. Listening to the Earth at these small magnitudes is crucial for identifying active zones and changes in seismic patterns, information that can guide the development of more precise monitoring systems and risk-mitigation strategies.
A Prototype for Microseismicity Detection
With this purpose in mind, an undergraduate research project (IPre) was launched at the UC School of Engineering, carried out by Valentina Pailamilla, an Electrical Engineering student, under the supervision of professors Leoncio Cabrera and Marcos Moreno from the Department of Structural and Geotechnical Engineering. The IPre project involved designing, developing, and installing a local, autonomous, and sustainable seismic monitoring system aimed at detecting microseismicity along the coast of the Valparaíso Region, specifically at the Coastal Marine Research Station (ECIM). Coastal Marine Research Station (ECIM).
This work is part of a larger SeedFund project funded by the School of Engineering, led by professors Leoncio and Marcos together with collaborating professors Gloria Arancibia and Jorge Crempien from the same department, with the goal of implementing a prototype seismic antenna at ECIM.
Students from various academic units also participated: Camila Ferrus and Constanza Parra (College UC) and Beatriz Bucchi and Micaela Molina (Natural Resources Engineering), who contributed to the installation and commissioning of the monitoring system.
ECIM: the hub of marine and geological research at La Punta del Lacho, Valparaíso Region.
ECIM is a coastal laboratory that is part of the Network of Regional Centers and Stations (RCER) of the Pontificia Universidad Católica de Chile. It combines research, teaching, and outreach in marine sciences, and also includes a Marine Coastal Protected Area. From its location in Las Cruces, the station supports interdisciplinary studies of the marine and coastal ecosystem, and now also focuses on seismic dynamics in the Valparaíso Region.
From Concept to Fieldwork: Building, Testing, and Installing
The IPre project unfolded across three main stages. In the first phase, Valentina assembled all the materials required for the field monitoring system: rechargeable batteries, connectors, cables, and an energy-management system. To ensure continuous operation in a coastal environment, the system also included a solar panel with a charge controller, preventing battery depletion and ensuring a stable power supply for the seismometers.
In the second phase, the research team conducted laboratory tests to verify communication between the seismometers and digitizers, GPS synchronization, and the quality of the recorded signals.
Finally, in the third and final phase, the team moved to ECIM. They selected a suitable site (flat, free of rocky formations, and away from foot traffic) and installed an initial test seismometer, which recorded data throughout the night. The following day, after confirming the quality of the recordings and validating the proof of concept, five additional instruments were added. These were arranged in a rectangular layout and spaced one meter apart, forming an experimental seismic array. This configuration ensured that all equipment was functioning correctly, allowed early detection of any potential issues, and facilitated the subsequent processing of the data.
Field Installation of the Seismometer Network
Exploring the Coast: Between Rocks and Tides
Beyond installation and seismic recording, the team also took the opportunity to explore the coastal environment from a geological perspective. Along the way, they identified various landscape features, such as the arrangement of rock layers and outcrops, rock structures that emerge at the surface due to erosion or tectonic uplift, along with possible evidence of ancient seismic activity. These observations complement the instrumental records by offering a broader understanding of the region’s geodynamics and revealing, in the landscape itself, an Earth in constant transformation.
Exploring the surroundings of ECIM at La Punta del Lacho, the team observed the coastal landscape and unexpectedly encountered a group of dolphins swimming (photo by Micaela Molina).
Electrical Engineering student
Estudiante de College UC - Ciencias NAturales
College UC Student – Natural Sciences
Student of Natural Resources Engineering
Student of Natural Resources Engineering
Department of Structural and Geotechnical Engineering
Department of Structural and Geotechnical Engineering
Department of Structural and Geotechnical Engineering
Department of Structural and Geotechnical Engineering
Press note: Installing Seismometers at ECIM
ECIM (Las Cruces), from the UC Network of Regional Centers and Stations
Se espera que los resultados de monitoreo permitan validar que una red de detección local, más cercana al área de interés, puede identificar una mayor cantidad de eventos sísmicos de menor magnitud (que suelen ser desapercibidos por las redes nacionales convencionales), además del correcto funcionamiento de los sismómetros que se probaron.
This project illustrates how engineering and geosciences (the study of Earth sciences) can come together to create hands-on learning experiences and open new avenues for studying microseismicity. The installation of the monitoring prototype along the coast of Las Cruces, with solar-powered seismometers operating under real conditions, laid the foundation for future research that could improve the detection of small earthquakes and deepen our understanding of the region’s seismic dynamics.
Small Movements, Big Revelations
Electrical Engineering student
Professor at the Department of Structural and Geotechnical Engineering
