Article
Geochemistry & Geophysics
Hong-Yan Li, Chao Xie, Jeffrey G. Ryan, Chuan-Mao Yang, Rui-Peng Zhao, Chao Zhang, Yi-Gang Xu
Summary: This study investigates the geochemical variations in volcanic rocks from the Kurile arc and identifies three different sources of material in the magma, including shallow slab-sourced low-temperature hydrous fluids and deeper high-temperature hydrous melts, as well as the metasomatized Kurile forearc mantle. The authors propose a new model to interpret these variations.
Article
Geosciences, Multidisciplinary
Kittiphon Boonma, Daniel Garcia-Castellanos, Ivone Jimenez-Munt, Taras Gerya
Summary: This study uses 3D thermo-mechanical geodynamic modelling to explore the processes of lithospheric slab tearing, and finds that the obliquity of the continental passive margin relative to the subduction trench facilitates the initiation of slab tearing. The model predicts a lateral migration velocity ranging between 38 and 68 cm/yr for the tearing point, resulting in uplift rates of 0.23-2.16 mm/yr above the torn apart areas, depending on mantle viscosity.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Geochemistry & Geophysics
Stephen J. Turner, Charles H. Langmuir
Summary: Hydrous arc magmas are produced when water-bearing materials from subducted oceanic plates are transported to the mantle beneath volcanic arcs. The study shows that both sediment and ocean crust melt in arc volcanism, and the contribution of aqueous fluids to arc mass-balance is limited. Oxygen fugacity has a significant effect on slab melting. The research findings have important implications for understanding arc volcanism and the fluxes of elements into the deep mantle.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geochemistry & Geophysics
Stephen J. Turner, Charles H. Langmuir
Summary: Arc magmas are generated by partial melting of a mantle wedge modified by inputs from subducting sediment and igneous ocean crust. This study presents an alternative framework that suggests a relatively constant proportion of slab material is added to varying mantle wedges, resulting in different melting extents and magma compositions. The framework can explain the global variations in arc volcanic systems and provides a tool for studying regional variations and unusual magma compositions.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geochemistry & Geophysics
Dong Fu, Bo Huang, Simon A. Wilde, Tim E. Johnson, Ali Polat, Brian F. Windley, Zhaochu Hu, Zhipeng Zhou, Timothy M. Kusky
Summary: The study reveals that the North Qilian back-arc basin in the northeastern region of the North Qilian orogenic belt underwent an early spreading phase and subsequent closure through two subduction episodes. The findings highlight the crucial role of back-arc oceanic crust subduction in the closure of back-arc basins, and the complex evolutionary tempo of such basins in Earth history.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Athanasios G. Ouzounis, George A. Papakostas
Summary: This study explores using machine learning algorithms to identify the provenance of volcanic rocks from the Hellenic Volcanic Arc (HVA) in Southern Greece. By training MLAs with geochemical data from the GEOROC database, the Extreme Gradient Boost model achieved the best performance with 93.07% accuracy. The model developed in this research has been implemented in a cloud-based application for predicting the provenance of volcanic rock samples within the HVA based on their geochemical composition.
APPLIED SCIENCES-BASEL
(2021)
Article
Multidisciplinary Sciences
Tiziana Sgroi, Alina Polonia, Graziella Barberi, Andrea Billi, Luca Gasperini
Summary: By studying low-to-moderate magnitude earthquakes and integrating data from a seafloor observatory, researchers have identified a major lithospheric boundary constituted by the Ionian Fault in the western Ionian Sea. This boundary separates two regions with varying thickness of the seismogenic layer, suggesting a complex tectonic setting involving arc-orthogonal extension and plate convergence.
SCIENTIFIC REPORTS
(2021)
Article
Geochemistry & Geophysics
Kun Guo, Xiaoyuan Wang, Shuai Chen, Luning Shang, Bingquan Liu, Xia Zhang, Zhiqing Lai
Summary: The Kueishantao (KST) area, located at the tectonic junction of the Okinawa Trough and the Ryukyu arc, is an ideal location to study the influence of the lower crust on the generation of back-arc magmas. Research shows that the KST andesitic magma is likely sourced from the lower continental crust.
Article
Geosciences, Multidisciplinary
Violeta Veliz-Borel, Vasiliki Mouslopoulou, Andrew Nicol, John Begg, Onno Oncken
Summary: This study focuses on the upper-plate normal faults along the forearc of the Hellenic Subduction System (HSS) in Greece. Detailed field-mapping and analysis of high-resolution Digital Elevation Models (DEMs) were used to study active normal faults on Kythira and Antikythira islands. The results show that these faults have different lengths and scarp heights, accommodating trench-orthogonal extension during the Quaternary. Rate variability between different time intervals and across the entire fault network suggests earthquake clustering may occur over relatively short timescales.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Geochemistry & Geophysics
Zihua Cheng, Fan Zhang, Jian Lin, Weiwei Ding, Xubo Zhang
Summary: This study investigates the evolution of forearc and backarc spreading in relation to Subduction Initiation (SI), using the unique evolution history of the Izu-Bonin-Mariana subduction system (IBM). Based on plate motion history and 2D thermomechanical models, the early stages of SI as well as the evolutions of forearc and backarc spreading were simulated. A new model with a delayed convergence rate after approximately 5 million years of SI was proposed to explain the observed phenomena in the IBM.
Review
Astronomy & Astrophysics
Esteban Gazel, Kennet E. Flores, Michael J. Carr
Summary: Central America provides a rich setting for studying arc magmatism, with a narrow volcanic front segmented by right steps at 150-km intervals, influenced by oblique subduction of the Cocos-Caribbean plate boundary. Volcanic centers located above depths of 90-110 km are larger and exhibit source geochemical heterogeneity. The composition of subducted oceanic lithosphere controls geochemical variations in Central American volcanoes, while lithospheric structures influence arc segmentation.
ANNUAL REVIEW OF EARTH AND PLANETARY SCIENCES, VOL 49, 2021
(2021)
Article
Geochemistry & Geophysics
Gino de Gelder, David Fernandez-Blanco, Nazik Ogretmen, Spyros Liakopoulos, Dimitris Papanastassiou, Costanza Faranda, Rolando Armijo, Robin Lacassin
Summary: This study provides a detailed tectonic reconstruction method by studying the geological and geomorphological features of Kythira Island. It is found that the island has experienced subsidence, transgression, regression, and uplift at different periods. Through model interpretation, it is believed that E-W extension is the dominant mode of regional active upper crustal deformation.
Article
Geochemistry & Geophysics
Stephen J. Turner, Mattison H. Barickman, Julian Rodriguez, David A. Fike, Clive M. Jones, Kun Wang, Ivan P. Savov, Samuele Agostini, Michael J. Krawczynski, Rita Parai
Summary: The geochemistry of arc magmas provides insight into the chemical outfluxes from subducting slabs. Boron (B) abundances and isotope ratios act as tracers of slab-derived components, with new measurements in Nicaraguan volcanic centers indicating a B-rich slab component primarily sourced from subducted altered oceanic crust (AOC) and minor input from subducted sediments. This finding suggests that the volatile element budget delivered to the volcanic arc is mostly derived from the ocean crust and that volatiles may be recycled into the deeper mantle beneath Central America.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Geochemistry & Geophysics
Inayat Ullah, Chuandong Xue, Tiannan Yang, Zhipeng Xie, Wei Wang, Abdul Ghaffar
Summary: This paper focuses on the RasKoh peridotites in western Pakistan's Sorap Massif, and provides insights into their origin and evolution. The authors identified three types of peridotites (lherzolite, harzburgite, and dunite) with gradational boundaries. Based on mineral compositions, major element contents, and rare earth element patterns, they suggest that the RasKoh ophiolite represents refractory residues of mantle peridotites after partial melting and melt-rock reaction. The authors propose that the ophiolite is a fragment of a former Triassic to Jurassic oceanic plate that became a mantle wedge above an intra-ocean subduction zone during the Cretaceous. Fluids from the subducted plate re-enriched the depleted peridotites of the RasKoh island arc.
Review
Geosciences, Multidisciplinary
Yener Eyuboglu, Francis O. Dudas, Di-Cheng Zhu, M. Santosh, Ze Liu, Nilanjan Chatterjee, Keewook Yi
Summary: The research on the Eastern Pontides Orogenic Belt in northeastern Turkey reveals a complex continental arc system with multi-stage Late Cretaceous magmatism showing different characteristics in terms of rock types and geochemical features, indicating a significant geological differentiation.