Article
Geosciences, Multidisciplinary
Jose Cruces-Zabala, Oliver Ritter, Ute Weckmann, Kristina Tietze, Naser Meqbel, Franck Audemard, Michael Schmitz
Summary: This study investigates the formation and subsurface structures of the Merida Andes using geophysical data, revealing important tectonic features in the region. The results show that the mountain chain is generally resistive in nature, and the analysis of off-profile conductors and gravity lows provide hypotheses about specific tectonic blocks and faults.
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2022)
Article
Geochemistry & Geophysics
Diego Jaldin, Laura Giambiagi, Fernando Martinez, Carlos Benavente, Daniela Espinoza, Kyriaki Drymoni, Karina Luengo, Rodrigo Gonzalez, Juan Rios-Contesse
Summary: The relationship between parallel and oblique faults and magmatic evolution is crucial in understanding the evolution of a hot orogen like the Central Andes. This study reconstructs the evolution of two main faults affecting the western slope of the Puna plateau during the Neogene using geomorphological observations, kinematic and dynamic analyses, and kinematic forward modeling. The results show that oblique faults control the segmentation of the reverse parallel-to-the-trench deformation and the position of volcanic centers, while parallel faults control relief development and the evolution of hydrothermal systems. This model helps explain how magma rises associated with movement along reverse and strike-slip faults during crustal thickening.
Article
Geosciences, Multidisciplinary
M. Daniela Tazzo-Rangel, Bodo Weber, Axel K. Schmitt, Renee Gonzalez-Guzman, Alejandro Cisneros de Leon, Lutz Hecht
Summary: The study in the Merida Andes of Venezuela explores metamorphic processes occurring in the Late Permian to Early Triassic, potentially related to the formation and breakup of Pangea. The findings suggest peak metamorphism around 251 million years ago, indicating tectonic processes post-collision leading to retrogression and eventual extensional setting associated with the Pangea breakup during the Late Triassic to Early Jurassic.
INTERNATIONAL JOURNAL OF EARTH SCIENCES
(2021)
Article
Geochemistry & Geophysics
Mathilde Marchandon, James Hollingsworth, Mathilde Radiguet
Summary: This study investigates the potential artifact of Shallow Slip Deficit (SSD) in fault slip models for large strike-slip earthquakes. Results show that neglecting topography, variations in elastic properties, and lack of data coverage around the fault can significantly bias the slip model, leading to artificial SSD. Additionally, correlated data noise with low amplitude can also produce significant artificial SSD, highlighting the importance of systematic estimation of model uncertainty in inversion studies.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Aitang Li, Chaodi Xie, Yingfeng Ji, Weiling Zhu, Yan Xu, Guangming Wang, Xiaoyan Zhao
Summary: On June 12, 2021, a magnitude 5.0 earthquake occurred in Yingjiang, Yunnan, which is prone to seismic activity due to plate collision. Researchers inverted the regional stress field of Yingjiang using the focal mechanisms of 187 historical earthquakes in the area to explore the mechanism of this earthquake. The results showed strike-slip-type stress accumulation in Yingjiang with a principal compressive stress axis direction-oriented NNE-SSW. The study also estimated the fault slip tendency, which indicated enhanced stress coupling in seismogenic faults within specific strike and dip ranges. The distribution of the aftershock sequence is believed to be correlated with local fluid migration and controlled by ruptures of stressed fault systems induced by hydrated rock near the source region. This study provides valuable insights into potential earthquake risks in the region.
APPLIED SCIENCES-BASEL
(2023)
Article
Geosciences, Multidisciplinary
Oswaldo Guzman, Marisel Diaz, Corina Campos, Aleida Gonzalez, Riccardo Vassallo, Nataly Aranda, Bruno Conicelli, Jesus Gonzalez-Laprea
Summary: The study demonstrates the potential for ESR dating of Quaternary sediments in Venezuela, emphasizing the importance of stable sedimentary conditions and long-term transport processes. The results show that ESR dating can align with Be-10 ages, but may overestimate ages in cases of rapid deposition. This study confirms the technological and human resources in Venezuela for numerical dating of Quaternary sediments.
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2021)
Article
Geochemistry & Geophysics
Zicheng Huang, Yu Zhou, Xin Qiao, Peizhen Zhang, Xiao Cheng
Summary: This study investigates the present-day strain accumulation on the Haiyuan fault system using synthetic aperture radar data. The study reveals that the slip rate of the fault gradually increases from west to east and identifies localized strain accumulation. Additionally, the study remaps the previously identified shallow creeping zone.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Konstantinos Chousianitis, A. Ozgun Konca
Summary: On October 30, 2020, a M(w)7.0 normal faulting earthquake struck the eastern Aegean Sea, causing casualties, and substantial damage at Samos island and Izmir province. By analyzing the rupture history of the main shock, it was found that the slip distribution was dominated by a slip patch spanning a depth range of 3-13 km. The low aftershock productivity within the main asperity implies a near complete stress release.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Waqar Ali Zafar, Farhan Javed, Rizwan Ahmed, Muhsan Ehsan, Kamal Abdelrahman, Mohammed S. Fnais, Mansoor Aziz Qureshi
Summary: The Kalabagh strike-slip fault is part of the northwestern Himalayan foreland fold and thrust belt in Pakistan, characterized by right-lateral movement. Through the analysis of SAR interferometry data, it was found that the southern and northern segments of the fault exhibit aseismic creeping, while the central section does not. The presence of a thick salt layer over the decollement facilitates the creeping on this fault and also causes vertical deformations.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Geochemistry & Geophysics
Yu Jiang, Sergey V. Samsonov, Pablo J. Gonzalez
Summary: Improved imaging of fault slip is crucial for understanding earthquakes and faulting. By introducing a new regularization method, we successfully recovered complex slip propagation patterns and estimated the spatio-temporal evolution of fault slip. Applying the method to a seismic swarm, we found that aseismic slip played a significant role and the slip rates were consistent with slow earthquake processes.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Multidisciplinary Sciences
Luis Astudillo-Sotomayor, Julius Jara-Munoz, Daniel Melnick, Joaquin Cortes-Aranda, Andres Tassara, Manfred R. Strecker
Summary: In the Liquirie-Ofqui Fault System in Southern Chile, a single fault segment has exhibited a rapid slip rate over the past millennia, indicating strain localization on the fault at millennial time scales but not sustained over longer time scales.
SCIENTIFIC REPORTS
(2021)
Article
Geosciences, Multidisciplinary
Yajian Gao, Xiaohui Yuan, Benjamin Heit, Frederik Tilmann, Dirk-Philip van Herwaarden, Solvi Thrastarson, Andreas Fichtner, Bernd Schurr
Summary: A new seismic model for the crust and upper mantle of the south Central Andes has been derived through full waveform inversion, covering the Pampean flat subduction and adjacent Payenia steep subduction segments. The study indicates the presence of partial melts along the volcanic arc in the Payenia segment, and suggests thinning and tearing of the flat Nazca slab. Furthermore, a high-velocity anomaly in the mantle below the flat slab is interpreted as relic Nazca slab segment, signifying an earlier slab break-off triggered by the Juan Fernandez Ridge.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geochemistry & Geophysics
Ian K. D. Pierce, Steven G. Wesnousky, Lewis A. Owen, Jayne M. Bormann, Xinnan Li, Marc Caffee
Summary: Geodesy research shows that a significant amount of dextral shear is accumulating in the Central Walker Lane, where no through-going strike-slip faults exist. The patterns and slip rates of active faults between Lake Tahoe and Walker Lake basins help understand how this shear is accommodated, with different fault types playing a role in releasing the accumulated strain.
Article
Energy & Fuels
Mukti M. Maruf, Maulin B. Hade, Permana Haryadi
Summary: The uplift mechanisms of the forearc high and the formation of the forearc basin in the oblique Sumatra subduction system are attributed to flexural uplift, basin inversion, older accretion wedge uplift, and backthrust. The interplay between trenchward-vergent thrusts and arcward-vergent backthrusts plays a major role in the uplift of the forearc high. The present-day morphology of the forearc high and forearc basin is related to the uplift of the accretionary wedge and overlying forearc basin sediments during Pliocene.
PETROLEUM EXPLORATION AND DEVELOPMENT
(2021)
Article
Geology
Dezheng Zhao, Chunyan Qu, Xinjian Shan, Roland Burgmann, Han Chen, Kathryn Materna
Summary: Recent geodetic observations have revealed complex slip behaviors on the Xidatan fault, including transient creep driven by postseismic deformation processes. This contradicts previous assumptions of locking along the fault and highlights the importance of understanding stress interactions in promoting slip behaviors throughout the earthquake cycle.
Article
Geosciences, Multidisciplinary
David Dominguez-Santos, Daniel Valderrama, Ahmet Utku Yazgan
Summary: This document presents a study comparing the spectra of large-magnitude seismic records in Chile between 2012 and 2022 with the design spectra of NCh433 and D. S 61. The aim is to determine if Chile's seismic-resistant regulations are updated to the existing reality and propose new design spectra that better represent the seismic activity in Chile during the last decade.
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2024)
Article
Geosciences, Multidisciplinary
Prabhu Palanisamy, Vivek Sivakumar, Priya Velusamy, Logesh Natarajan
Summary: Shoreline changes in the southern coast of Rio de Janeiro, Brazil, were analyzed from 1986 to 2018. The study found that both natural and human factors significantly impact shoreline changes. The findings provided important insights into predicting future shoreline positions and identifying vulnerable regions. Additionally, human activities were found to influence shoreline change models, emphasizing the need for effective management strategies to protect ecosystems and communities.
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2024)
Article
Geosciences, Multidisciplinary
Irina Salgado Bernal, Periyasamy Sivalingam, Armando Martinez Sardina, Michel Manduca Artiles, Maria E. Carballo Valdes, John Pote
Summary: This study investigated the presence of 15 toxic metals in surface sediment in a tropical river ecosystem in Cuba. The results showed that the sediments had higher concentrations of four metals compared to Cuban norms. Various contamination indices were calculated, and correlations analysis revealed the main sources of contamination. The study provides important information for the management of the river and emphasizes the need for metal pollution control and monitoring.
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2024)
Article
Geosciences, Multidisciplinary
Camila Morgan, Eduardo Morgado, Miguel-Angel Parada, Raimundo Brahm, Francisca Mallea-Lillo
Summary: Lanin volcano is a composite volcano in the Andes, which has erupted lava flows with different compositions. The volcano's magma reservoir contains a crystal mush, and the pre-eruptive conditions include temperature, pressure, and oxygen fugacity. Fractional crystallisation has led to the evolution of the magma with different compositions.
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2024)
Article
Geosciences, Multidisciplinary
Benjamin Idini, Sergio Ruiz, Jean-Paul Ampuero, Felipe Leyton, Efrain Rivera
Summary: This study investigates the role of wedge integrity on the frequency content of strong ground motion produced by subduction earthquakes in Northern Chile. The results show that the frequency characteristics of seismic waves vary with hypocentral distance, indicating lateral variations in anelastic attenuation due to the heterogeneous tectonic structure.
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2024)