Alberto M. López Venegas

• PhD
• Professor (Full) at University of Puerto Rico System

The M6.4 mainshock of the southwestern Puerto Rico seismic sequence on 7 January 2020, was one of the most impactful modern earthquakes in the northeastern Caribbean. Due to its offshore location and complex aftershock distribution, its source kinematics remain poorly constrained. This active sequence illuminated a complex set of previously unrecog...

The Puerto Rico–Virgin Islands (PRVI) block lies within the Northern Caribbean Plate Boundary Zone—a zone accommodating stresses between the larger North America and Caribbean plates. Data from Global Positioning System (GPS) sites throughout the PRVI block have been used to confirm the existence of a distinct microblock in the southwest. It is no...

Distributed faulting typically tends to coalesce into one or a few faults with repeated deformation. The progression of clustered medium‐sized (≥Mw4.5) earthquakes during the 2020 seismic sequence in southwestern Puerto Rico (SWPR), modeling shoreline subsidence from InSAR, and sub‐seafloor mapping by high‐resolution seismic reflection profiles, su...

We analyzed synthetic aperture radar (SAR) images from Copernicus Sentinel-1A and -1B satellites operated by the European Space Agency and the Advanced Land Observation Satellite-2 (ALOS-2) satellite operated by Japanese Aerospace Exploration Agency for the earthquakes near the southwest coast of Puerto Rico in January 2020 and for later deformatio...

Regional networks of Global Navigation Satellite System (GNSS) stations cover seismically and volcanically active areas throughout the United States. Data from these networks have been used to produce high‐precision, three‐component velocity fields covering broad geographic regions as well as position time series that track time‐varying crustal def...

An international collaboration is using historical records and modeling to assess tsunami potential in this high-risk region. https://eos.org/project-updates/nations-work-together-to-size-up-caribbean-tsunami-hazards

The presence of Tectonic Earthquake Swarms (TES) and sequences in the north and northeast of the island of Puerto Rico in the northeastern Caribbean have been recorded by the Puerto Rico Seismic Network (PRSN) since it started operations in 1974. A great wealth of seismic data has been archived during this period such that at least 10 years of cata...

Historical records have shown that tsunami have affected the Caribbean region in the past. However infrequent, recent studies have demonstrated that they pose a latent hazard for countries within this basin. The Hazard Assessment Working Group of the ICG/CARIBE-EWS (Intergovernmental Coordination Group of the Early Warning System for Tsunamis and O...

The Puerto Rico Seismic Network (PRSN) is an integral part of earthquake and tsunami monitoring in Puerto Rico and the Virgin Islands. The PRSN conducts scientific research as part of the University of Puerto Rico Mayaguez, conducts the earthquake monitoring for the region, runs extensive earthquake and tsunami education and outreach programs, and...

The presence of earthquake swarms and clusters in the north and northeast of the island of Puerto Rico in the northeastern Caribbean have been recorded by the Puerto Rico Seismic Network (PRSN) since it started operations in 1974. Although clusters in the Puerto Rico-Virgin Island (PRVI) block have been observed for over forty years, the nature of...

Given the limited human resources available to interact directly with the public and disseminate information on earthquake and tsunami safety, the Puerto Rico Seismic Network has developed the Train the Trainers course, designed exclusively for emergency management officers (EMOs). This three-day training course provides a complete package of educa...

The Caribbean region has a documented history of damaging earthquakes and tsunamis that have affected coastal areas (Jamaica ,1692; Virgin Islands, 1867; Mona Passage, 1918; Dominican Republic, 1946, and Haiti, 2010). There is evidence that tsunamis have been triggered by large earthquakes that deformed the ocean floor around the Caribbean Plate (C...

For exactly 85 years the island of Puerto Rico in the northeastern Caribbean was spared from catastrophic category 4 hurricane winds. Then Hurricane Maria arrived on September 20, 2017 with maximum sustained winds of up to 155 mph. The eye of the hurricane crossed the island from southeast to northwest in eight hours leaving almost a meter of rainf...

Mater Thesis

The determination of earthquake locations are dependent on the velocity model selected. Consequently, the refinement and updating of the velocity models used at the local and regional network level is a critical component for network efficiency through location accuracy. With the expansion of broadband instruments within the Puerto Rico -Virgin Isl...

The most recent tsunami observed along the coast of the island of Puerto Rico occurred on October 11, 1918, after a magnitude 7.2 earthquake in the Mona Passage. The earthquake was responsible for initiating a tsunami that mostly affected the northwestern coast of the island. Runup values from a post-tsunami survey indicated the waves reached up to...

The Mwp 6.4 January 13, 2014 earthquake occurring 75 km north of the Puerto Rico coast is the largest event recorded by the Puerto Rico Seismic Network (PRSN) since its inception in the mid 70's. Moderate size earthquakes such as this one and larger events have been rare in the historic record for the Northeastern Caribbean. Among the most recent l...

Although the Caribbean plate region is characterized by slow (~2 cm/yr) plate motions, it is still prone to earthquakes and tsunamis along its boundaries where most of the land is concentrated (Jasma and Mattioli, 2005; López et al., 2006; DeMets et al., 2007). Moreover, most of the population residing on these active tectonic regions is concentrat...

The fore-arc region of the northeast Caribbean plate north of Puerto Rico and the Virgin Islands has been the site of numerous seismic swarms since at least 1976. A 6 month deployment of five ocean bottom seismographs recorded two such tightly clustered swarms, along with additional events. Joint analyses of the ocean bottom seismographs and land-b...

The boundaries of the Caribbean plate are deforming as a result of the interaction with the North and South American plates. These regions of deformation generate earthquakes and tsunamis that can be devastating to the islands of the Caribbean basin. Therefore, monitoring seismic activity and tsunami genesis, and alerting vulnerable communities is...

The Puerto Rico-Virgin Islands (PRVI) block lacks a tomography image to explain the location and geometry of the North American subducting slab under the Caribbean plate. Not knowing the exact location of the subducting slab may hinder accurate hypocenter locations. This serve as evidence that this region is complex, at least in the seismological s...

Waters from the Atlantic Ocean washed southward across parts of Anegada, east-northeast of Puerto Rico, during a singular event a few centuries ago. The overwash, after crossing a fringing coral reef and 1.5km of shallow subtidal flats, cut dozens of breaches through sandy beach ridges, deposited a sheet of sand and shell capped with lime mud, and...

Kinematic similarities between the Sumatra and Puerto Rico Trenches highlight the potential for a mega-earthquake along the Puerto Rico Trench and the generation of local and trans-Atlantic tsunamis. We used the horizontal components of continuous GPS (cGPS) measurements from 10 sites on NE Caribbean islands to evaluate strain accumulation along th...

Seismic networks need quick and efficient ways to obtain information related to seismic events for the purposes of seismic activity monitoring, risk assessment, and scientific knowledge among others. As part of an IRIS summer internship program, two projects were performed to provide a tool for quick faulting mechanism and improve seismic data at t...

The Puerto Rico - Virgin Island microplate, a crustal block within the deformation region of the Northern Caribbean Plate Boundary Zone has been monitored with campaign and permanent Global Positioning System stations for almost 20 years. Within this time period a total of 37 sites have been used to describe and quantify internal deformation of the...

We present preliminary results of relocating over 2474 events in the crust and upper mantle of Puerto Rico recorded by the Puerto Rico Seismic Network (PRSN) from 1986 to 2009. This seismic activity is the result of the interaction of the Caribbean and North American plates primarily along the Puerto Rico Trench. We start with the one-dimensional (...

Puerto Rico and the Virgin Islands (PRVI) block lie on the northeastern boundary of the Caribbean plate, where active transpressional tectonics result in the deformation of the boundaries of this block. Every year hundreds of earthquakes occur within and around PRVI region and at least four destructive earthquakes after 1700 are documented in the h...

Seismic swarms along the Northeastern corner of the Caribbean plate have been recorded at the Puerto Rico Seismic Network for more than three decades. The nature of these events is still uncertain due to limited azimuthal coverage by seismographic stations. A six-month deployment of five ocean bottom seismographs (OBS) in 2007 is helping us underst...

Over the last thirty years seismic swarm activity has frequently occurred offshore northeast of Puerto Rico. Seismic swarms have been recorded lasting from one day up to several weeks with magnitudes commonly no more than mb 4. Causes of these swarms have yet to be determined; however, some have proposed a tear, or crumpling, of the subducting Nort...

The Northeastern corner of the Puerto Rico - Virgin Islands tectonic block has experienced numerous seismic swarms over the past three decades. The earthquakes, located initially by the Puerto Rico Seismic Network (PRSN), occur in the area denominated as the Sombrero Seismic Zone, a region on the forearc of the Puerto Rico trench north of the Virgi...

Persistent seismic swarms northeast of the Puerto Rico-Virgin Islands (PRVI) tectonic block have been recorded and documented for more than a decade. The heightened seismicity typically lasts for days to weeks and consists primarily of hundreds of Ms < 4 events, but events up to Ms 6 have been recorded. The active region (sometimes called the "Somb...

The October 11, 1918 ML 7.5 earthquake in the Mona Passage betweeen Hispaniola and Puerto Rico generated a local tsunami that claimed approximately 100 lives along the western coast of Puerto Rico. The area affected by this tsunami is now many-fold more populated. Although the exact cause of the tsunami is still unclear, newly-acquired high-resolut...

The Northeast Caribbean Plate boundary is prone to tsunamis due to the occurrence of a) subduction zone earthquakes along the Lesser Antilles and the Hispaniola and Puerto Rico trenches, b) other large earthquakes due to more local tectonic activity, such as in the Mona Passage (1918 tsunami) and in the Virgin Islands basin (1867 tsunami), and c) m...

Although 60 years have passed since the occurrence of the August 4, 1946 earthquake in Hispaniola, overall knowledge and essential parameters of the event are still unknown or poorly constrained. Published magnitudes for the event have ranged from 7.8 to 8.1, estimated fault zone dimensions have had poor agreement between them, and waveform inversi...

We present a re-evaluation of the seismological properties of the Aleutian ‘tsunami earthquake’ of 1946 April 1, characterized by a deceptively low conventional magnitude (7.4) in view of its catastrophic tsunami, both in the near and far fields. Relocation of 40 aftershocks show that the fault zone extends a minimum of 181 km along the Aleutian tr...

A systematic discrepancy exists between slip vectors of thrust fault earthquakes at the Lesser Antilles trench (LAT) and the predicted direction of North American-Caribbean convergence. A possibility has been that the discrepancy resulted because neither was well constrained. Estimating Caribbean motion has been challenging owing to the limited dat...

New Global Positioning System (GPS) data from nine sites within stable portions of the Caribbean (CA) plate have been used to constrain its motion in the International GPS Service reference frame (IGSb00) and with respect to North (NA) and South (SA) American plates. A comparison of GPS velocities between eastern and western Caribbean sites shows t...

Spanish is estimated to be the fourth language in the world based on number of speakers, the second as a vehicle of international communication and the third as an international language of politics, economics and culture. Its importance in the U.S. is illustrated by the fact that the Hispanic/Latino population is becoming the largest minority grou...

An intriguing question concerning the Northeastern Caribbean is the occurrence of a systematic discrepancy between slip vectors of thrust fault earthquakes at the Lesser Antilles trench (LAT) and the predicted direction of convergence between North American (NA) and Caribbean (CA) plates. Although it had seemed possible that the discrepancy resulte...

We are using a decade of Global Positioning System data to address two tectonic problems of the Caribbean (CA) plate; 1) Whether a forearc sliver exists along the Lesser Antilles forearc and if so what is its dynamics and location, and 2) Whether the Caribbean plate is deforming internally. We approach this problem by developing GPS-derived velocit...

The boundary between the North American and Caribbean plates is characterized primarily by left-lateral motion along predominantly east-west striking faults. Seismicity and marine geophysical survey data are consistent with at least two, and possibly three, microplates in the diffuse boundary zone in the northeastern Caribbean: (1) the Gonave, (2)...