Alessandro Verdecchia

• Dr. rer. nat.
• PostDoc Position at Ruhr University Bochum

The region north of the Garlock fault between the Sierra Nevada and Death Valley has experienced at least eight Mw ≥ 6 earthquakes in historical times, beginning with the 1872, Mw 7.5, Owens Valley earthquake. Furthermore, since 1978, the Long Valley caldera has been undergoing periods of unrest, with earthquake swarms and resurgence. Our goal is t...

Dynamic stresses on the order of ~1 kPa from passing waves of mainshock earthquakes can trigger aftershocks at remote distances. Here, we investigate the prevalence of remote earthquake triggering in northern Chile, where aseismic-slip triggering has been documented. Our twofold approach to quantify triggerability includes a statistical difference-...

This study examines the impact of polyphase tectonics on the development of structurally controlled hydrothermal fluid pathways in carbonate geothermal reservoirs. Our case study focuses on hydrothermal carbonate veins and vein-filled faults in Devonian carbonates from the North Rhine-Westphalia region in western Germany, currently being explored a...

This study critically examines the use of geodetic strain rates for forecasting long-term earthquake rates in a slow-deforming region such as Italy, challenging the prevailing assumption of their temporal stationarity in interseismic stages for seismic hazard analyses. Typically, earthquake-rate models derived from geodesy assume stationary interse...

Changing stress regimes control fracture network geometry and influence porosity and permeability in carbonate reservoirs. Using outcrop data analysis and a displacement-based linear elastic finite-element method, we investigate the impact of stress regime change on fracture network permeability. The model is based on fracture networks, specificall...

The 6 February 2023, Mw 7.8 Pazarcık earthquake in the Turkey‐Syria border region raises the question of whether such a large earthquake could have been foreseen, as well as what is the maximum possible magnitude (Mmax) of earthquakes on the East Anatolian Fault (EAF) system and on continental transform faults in general. To answer such questions,...

Fluid injection/extraction activity related to hydraulic fracturing can induce earthquakes. Common mechanisms attributed to induced earthquakes include elevated pore pressure, poroelastic stress change, and fault loading through aseismic slip. However, their relative influence is still an open question. Estimating subsurface rock properties, such a...

The February 6, 2023, M 7.8 Pazarcık earthquake in the Turkey-Syria border region raises the question of whether such a large earthquake could have been foreseen, as well as what is the maximum possible magnitude (M) of earthquakes on the East Anatolian fault system and on continental transform faults in general. To answer such questions, knowledge...

The success of deep geothermal systems depends on the presence of fault zones in the subsurface. Faults play a vital role in the Earth's plumbing system by facilitating fluid flow when they dilate, but are simultaneously known to enhance the hazard of the system once slipping in shear mode. As dilation of a fault enhances its permeability significa...

The February 6, 2023, M 7.8 Pazarcık earthquake in the Turkey-Syria border region raises the question of whether such a large earthquake could have been foreseen, as well as what is the maximum possible magnitude (M) of earthquakes on the East Anatolian fault system and on continental transform faults in general. To answer such questions, knowledge...

Changes in stress regimes impact the geometry of fracture networks and affect the porosity and permeability of carbonate reservoirs. This is, predominantly, because of the complexity of the deformation phases, the poor understanding of the mechanical and diagenetic mechanisms that affect apertures, and the difficulty in precisely characterizing ape...

The observational difficulties and the complexity of earthquake physics have rendered seismic hazard assessment largely empirical. Despite increasingly high-quality geodetic, seismic and field observations, data-driven earthquake imaging yields stark differences and physics-based models explaining all observed dynamic complexities are elusive. Here...

The February 6th, 2023, Mw 7.8 Pazarcık earthquake in the Turkey-Syria border region raises the question of whether such a large earthquake could have been foreseen, as well as what is the maximum possible magnitude (Mmax) of earthquakes on the East Anatolian fault system and on continental transform faults in general. To answer such questions, kno...

Previous studies mainly attribute injection‐induced earthquakes (IIE) to hydraulic fracturing (HF) operations in the Western Canada Sedimentary Basin (WCSB), whereas the role of wastewater disposal (WD) has been largely overlooked. One particular reason is that HF operations usually exhibit a clearer spatiotemporal relationship to IIE than WD. Howe...

Intraplate tectonic stress fields are complex due to the imprint of a long geological history. Here we use a new data set of earthquake focal mechanism solutions and relocated events to investigate the relationship between regional stress, crustal strength, and seismicity in the Charlevoix Seismic Zone (CSZ), the most active seismic zone in eastern...

Changing stress regimes control fracture network geometry and influence porosity and permeability in carbonate reservoirs. We investigate the impact of stress-regime change on fracture network permeability utilizing outcrop data analysis and a displacement-based linear elastic finite element method. The model is based on fracture networks, specific...

Earthquakes and slow‐slip events interact, however, detailed studies investigating their interplay are still limited. We generate the highest resolution microseismicity catalog to date for the northern Armutlu Peninsula in a ∼1‐year period to perform a detailed seismicity distribution analysis and correlate the results with a local, geodetically ob...

The overwhelming observational difficulties and the complexity of earthquake physics have rendered seismic hazard assessment largely empirical. Despite increasingly high-quality geodetic, seismic, and field observations, data-driven earthquake imaging yields stark differences and physics-based models explaining all observed dynamic complexities are...

Intraplate tectonic stress fields are complex due to the imprint of a long geological history. Here we use a new dataset of earthquake focal mechanism solutions and relocated events to investigate the relationship between regional stress, crustal strength, and seismicity in the Charlevoix Seismic Zone (CSZ), the most active seismic zone in eastern...

The static stress drop of an earthquake is an indicator of the stress state of a specific fault before rupture initiation. The stress state is primarily controlled by the ambient stress field, fault strength, fault complexity, and the presence of fluids. This study aims to investigate the spatio‐temporal distribution of static stress drop values of...

A multi-proxy field and laboratory study was conducted to investigate the impact of a regional fault zone on Devonian carbonate geothermal reservoir properties. The outcrop analogue chosen is exposed in the Steltenberg quarry (North Rhine-Westphalia, Germany) and provides access to Devonian lime- and dolostone units affected by branches of the Enne...

An increase in injection activity associated with energy production in southern Kansas starting in 2013 has been linked to the occurrence of more than 130,000 earthquakes (M −1.5 to 4.9) between 2014 and 2017. Studies suggest that the dramatic increase in seismicity rate is related to wastewater injection into the highly permeable Arbuckle formatio...

The Mw 4.6 earthquake that occurred on 17 August 2015 northwest of Fort St. John, British Columbia, is considered the largest hydraulic-fracturing-induced event in Canada, based on its spatiotemporal relationship with respect to nearby injection operations. There is a ∼5 day delay of this Mw 4.6 mainshock from the onset of fluid injection at the cl...

Plain Language Summary Seismicity linked to hydraulic fracturing (HF) in shale gas exploration in western Canada has increased drastically over the last decade. However, details of induced seismicity sequence evolution and triggering mechanism(s) remain unclear. In this study, we integrate local seismic monitoring and numerical stress modeling for...

The number of earthquakes in the western Canada sedimentary basin (WCSB) has increased drastically in the last decade related to unconventional energy production. The majority of reported earthquakes are correlated spatially and temporally with hydraulic fracturing (HF) well stimulation. In this study, we use waveform data from a new deployment of...

Megathrust roughness and structural complexity are thought to be controls on earthquake slip at subduction zones because they result in heterogeneity in shear strength and resolved stress. However, because active megathrust faults are difficult to observe, the causes and scales of complexity are largely unknown. Here we measured the in situ propert...

Static and quasi-static Coulomb stress changes produced by large earthquakes can modify the probability of occurrence of subsequent events on neighboring faults. This approach is based on physical (Coulomb stress changes) and statistical (probability calculations) models, which are influenced by the quality and quantity of data available in the stu...

Static and quasi-static Coulomb stress changes produced by large earthquakes can modify the probability of occurrence of subsequent events on neighboring faults. This approach is based on physical (Coulomb stress changes) and statistical (probability calculations) models, which are influenced by the quality and quantity of data available in the stu...

Central Italy is characterized by a network of active faults that interact in a complex manner. Coseismic Coulomb stress changes have been invoked by several authors to explain the concentration of moderate-to-strong earthquakes in this region, but none has considered the time-dependent viscoelastic relaxation of the lower crust and upper mantle as...

Diffuse plate boundaries are characterized by deformation distributed over a wide area in a complex network of active faults, and by relatively low strain rates. These characteristics make it difficult to understand the spatial and temporal distribution of seismicity. The area east of the Sierra Nevada, between longitudes 121° W and 116° W, is part...

Diffuse plate boundaries are characterized by deformation distributed over a wide area in a complex network of active faults, and by low strain rates. These characteristics make it difficult to understand the spatial and temporal distribution of seismicity. The northern Basin and Range Province (BRP) in the western United States is an excellent exa...

Static and quasi-static Coulomb stress changes produced by large earthquakes can modify the probability of occurrence of subsequent events on neighbouring faults. In order to better understand and minimize the uncertainties in this kind of approach based on physical (Coulomb stress changes) and statistical (probability calculations) models, we focu...

The Gulf of California, Mexico accommodates ~90% of North America – Pacific plate relative motion. While most of this motion occurs on marine transform faults and spreading centers, several fault segments in the central Gulf come close to peninsular Baja California. Here we present Global Positioning System (GPS) and Interferometric SAR (InSAR) dat...

The region north of the Garlock fault between the Sierra Nevada and Death Valley has experienced at least eight Mw ≥ 6 earthquakes in historical times, beginning with the 1872, Mw 7.5, Owens Valley earthquake. Furthermore, since 1978, the Long Valley caldera has been undergoing periods of unrest, with earthquake swarms and resurgence. Our goal is t...

The temporal and spatial correlation among earthquakes in diffuse plate boundary zones is not well understood yet. The region north of the Garlock fault between the Sierra Nevada and Death Valley is part of a diffuse plate boundary zone, which absorbs a significant fraction of the plate motion between Pacific and North America. This area has experi...

Diffuse plate boundary regions are characterized by high deformation rates distributed over a wide zone. The correlation of seismic activity between faults in these regions is not yet well understood. The region between eastern California and western Nevada is part of such a diffuse plate boundary. The purpose of our work is to determine how faults...

Diffuse plate boundary regions are characterized by a high rate of deformation, but distributed over a wider zone when compared to plate boundary faults like the San Andreas and the North Anatolian faults. In diffuse plate boundaries the space-time relationship between activity on specific faults and the location of previous and subsequent events i...

Diffuse plate boundary regions are characterized by a high rate of deformation, but distributed over a wider zone when compared to plate boundary faults like the San Andreas and the North Anatolian faults. In diffuse plate boundaries the space–time relationship between activity on specific faults and the location of previous and sub-sequent events...