@article{MTMT:35337141, title = {Refining tomography with generative neural networks trained from geodynamics}, url = {https://m2.mtmt.hu/api/publication/35337141}, author = {Santos, T. and Bodin, T. and Soulez, F. and Ricard, Y. and Capdeville, Y.}, doi = {10.1093/gji/ggae240}, journal-iso = {GEOPHYS J INT}, journal = {GEOPHYSICAL JOURNAL INTERNATIONAL}, volume = {238}, unique-id = {35337141}, issn = {0956-540X}, keywords = {TOMOGRAPHY; machine learning; Statistical methods; Inverse theory; Bayesian inference}, year = {2024}, eissn = {1365-246X}, pages = {1676-1695} } @article{MTMT:35300712, title = {Seismic structure of the Balmuccia Peridotite from a high-resolution refraction and reflection survey}, url = {https://m2.mtmt.hu/api/publication/35300712}, author = {Pasiecznik, Damian and Greenwood, Andrew and Bleibinhaus, Florian and Hetényi, György}, doi = {10.1093/gji/ggae239}, journal-iso = {GEOPHYS J INT}, journal = {GEOPHYSICAL JOURNAL INTERNATIONAL}, volume = {238}, unique-id = {35300712}, issn = {0956-540X}, abstract = {In anticipation of a forthcoming scientific deep drilling initiative within the Western Alps near Balmuccia, Italy, a high-resolution seismic survey is performed at the proposed drill site. This site is situated within the Ivrea Verbano Zone (IVZ), characterized by lower crustal materials and fragments of upper-mantle rocks exposed adjacent to the Insubric Line. The 2-km-long seismic survey crosses an isolated km-scale outcrop of peridotite near the town of Balmuccia. Applying P-wave traveltime tomography, a substantial contrast in seismic velocities is identified, with velocities in the range of 1–8 km s−1. The peridotite displays velocities ranging from 6 to 8 km s−1. The higher velocities near 8 km s−1 are consistent with laboratory measurements on small-scale samples, while the low-velocity areas within the peridotite body reflect the influence of fractures and faults. The mean velocity derived for the peridotite body is ca. 7 km s−1. The reflection seismic analysis reveals subvertical reflectors positioned at the peridotite boundaries mapped at the surface, converging at a depth of ca. 0.175 km b.s.l. which images a lens-like structure for the peridotite body. However, the area beneath the imaged lens and the deeper Ivrea Geophysical Body (IGB) suggested by earlier studies is not well imaged, which leaves room for other interpretations regarding the relationship of these two bodies. Prior geophysical investigations provide only approximate depth estimates for the top of the IGB, spanning between 1–3 km depth b.s.l. Although the reflection data do not exhibit a series of continuous reflectors beneath the peridotite, a prominent reflection at ca. 1.3 km depth may indicate the top of the IGB.}, year = {2024}, eissn = {1365-246X}, pages = {1612-1625}, orcid-numbers = {Bleibinhaus, Florian/0000-0003-2176-4045; Hetényi, György/0000-0001-9036-4761} } @article{MTMT:35273301, title = {The inclined conductive column effect: a new simple model for magnetotelluric anomalous phases}, url = {https://m2.mtmt.hu/api/publication/35273301}, author = {Inoue, Tomohiro and Hashimoto, Takeshi}, doi = {10.1093/gji/ggae252}, journal-iso = {GEOPHYS J INT}, journal = {GEOPHYSICAL JOURNAL INTERNATIONAL}, volume = {238}, unique-id = {35273301}, issn = {0956-540X}, keywords = {Numerical modelling; magnetotellurics; Electromagnetic structure}, year = {2024}, eissn = {1365-246X}, pages = {1825-1839} } @article{MTMT:34954078, title = {2-D Sn wave attenuation tomography beneath the Eastern Himalaya}, url = {https://m2.mtmt.hu/api/publication/34954078}, author = {Sarkar, Sukanta and Singh, Chandrani and Tiwari, Ashwani Kant and Kumar, M. Ravi and Dubey, Arun Kumar and Dutta, Abhisek and Kumar, Gaurav and Singh, Arun}, doi = {10.1093/gji/ggae123}, journal-iso = {GEOPHYS J INT}, journal = {GEOPHYSICAL JOURNAL INTERNATIONAL}, volume = {237}, unique-id = {34954078}, issn = {0956-540X}, keywords = {seismic tomography; Wave propagation; seismic attenuation}, year = {2024}, eissn = {1365-246X}, pages = {1490-1504}, orcid-numbers = {Kumar, Gaurav/0000-0001-8062-3395} } @article{MTMT:34681534, title = {Estimating shallow compressional velocity variations in California's Central Valley}, url = {https://m2.mtmt.hu/api/publication/34681534}, author = {Vasco, DW and Pride, SR and Nakagawa, S and Plesch, A and Shaw, JH}, doi = {10.1093/gji/ggae009}, journal-iso = {GEOPHYS J INT}, journal = {GEOPHYSICAL JOURNAL INTERNATIONAL}, volume = {236}, unique-id = {34681534}, issn = {0956-540X}, year = {2024}, eissn = {1365-246X}, pages = {1680-1698} } @article{MTMT:34667670, title = {Anisotropic tomography and mantle dynamics of the North China Craton}, url = {https://m2.mtmt.hu/api/publication/34667670}, author = {Guo, Huili and Zhao, Dapeng and Ding, Zhifeng}, doi = {10.1093/gji/ggad497}, journal-iso = {GEOPHYS J INT}, journal = {GEOPHYSICAL JOURNAL INTERNATIONAL}, volume = {236}, unique-id = {34667670}, issn = {0956-540X}, keywords = {seismic tomography; SEISMIC ANISOTROPY; Dynamics of lithosphere and mantle; Body waves; cratons}, year = {2024}, eissn = {1365-246X}, pages = {1455-1470} } @article{MTMT:34586084, title = {Sedimentary structures of the western part of the Indo-Gangetic Plain and Siwalik Himalaya inferred from receiver function inversion}, url = {https://m2.mtmt.hu/api/publication/34586084}, author = {Das, Amlanjyoti and Hazarika, Devajit and Kundu, Abhishek and Kumar, Naresh and Yadav, Dilip K.}, doi = {10.1093/gji/ggad499}, journal-iso = {GEOPHYS J INT}, journal = {GEOPHYSICAL JOURNAL INTERNATIONAL}, volume = {236}, unique-id = {34586084}, issn = {0956-540X}, abstract = {We investigated sedimentary thickness and shear wave velocity structure in the western part of the Indo-Gangetic Plain (Punjab and Haryana Plain) and adjoining Siwalik Himalaya with the help of receiver function inversion at 20 broad-band seismological stations. This region is one of the most seismically vulnerable zones of the world due to the presence of thick surface sediments in the foreland basin that can amplify seismic waves and cause huge damage due to the earthquakes of the Himalaya. The study reveals a progressive thickening of sediments from southwest to northeast. The basement depth varies from similar to 1.5 to 1.7 km in the Central Alluvium Plain, similar to 1.8 to 2.8 km in the Zone of Terminal Fans, and attains a maximum of similar to 3.8 km near the Himalayan Frontal Thrust. The inverted models show the presence of soft alluvial with extremely low Vs (< 0.5 km s(-1)) and high Vp/Vs (similar to 2.5-3.0) at the top similar to 400-700 m of the surface at most of the stations. A comparatively higher velocity of surface sediments observed at northern stations suggests the presence of compact sediments at the surface. The layered sedimentary structure revealed by the S-wave velocity models supports the previous geophysical investigations using borehole data. The velocity-depth structure obtained in this study is important for evaluating the seismic hazard of the densely populated urban areas spread over this region.}, keywords = {Crustal structure; Waveform inversion; Sedimentary basin processes}, year = {2024}, eissn = {1365-246X}, pages = {1424-1438} } @article{MTMT:34580130, title = {Geophysical imaging of the active magmatic intrusion and geothermal reservoir formation beneath the Corbetti prospect, Main Ethiopian Rift}, url = {https://m2.mtmt.hu/api/publication/34580130}, author = {Dambly, M. L. T. and Samrock, F. and Grayver, A. and Eysteinsson, H. and Saar, M. O.}, doi = {10.1093/gji/ggad493}, journal-iso = {GEOPHYS J INT}, journal = {GEOPHYSICAL JOURNAL INTERNATIONAL}, volume = {236}, unique-id = {34580130}, issn = {0956-540X}, abstract = {Silicic volcanic complexes in the Main Ethiopian Rift (MER) system host long-lived shallow magma reservoirs that provide heat needed to drive geothermal systems. Some of these geothermal systems in Ethiopia appear to be suitable for green and sustainable electricity generation. One such prospect is located at the Corbetti volcanic complex near the city of Awassa. High-resolution imaging of the subsurface below Corbetti is of imminent importance, not only because of its geothermal potential, but also due to reported evidence for an ongoing magmatic intrusion. In this study, we present a new subsurface 3-D electrical conductivity model of Corbetti obtained through the inversion of 120 magnetotelluric stations. The model elucidates a magmatic system under Corbetti and reveals that it is linked to a magma ponding zone in the lower crust. Magma is transported through the crust and accumulates in a shallow reservoir in form of a magmatic mush at a depth of (sic) 4 kmb.s.l. below the caldera. The imaged extent and depth of the shallow magma reservoir is in agreement with previous geodetic and gravimetric studies that proposed an ongoing magmatic intrusion. Interpreting our model with laboratory-based conductivity models for basaltic and rhyolitic melt compositions suggests that Corbetti is seemingly in a non-eruptible state with similar to 6-16 vol. per cent basaltic melt in the lower crust and similar to 20-35 vol. per cent rhyolitic melt in the upper crust. With these observations, Corbetti's magmatic system shares common characteristics with volcanic complexes found in the central MER. Specifically, these volcanic complexes are transcrustal two-stage magmatic systems with magma storage in the lower and upper crust that supply heat for volcano-hosted high-temperature geothermal systems above them. According to the presented subsurface model, a cross-rift volcano-tectonic lineament exerts first-order controls on the magma emplacement and hydrothermal convection at Corbetti. Our study depicts hydrothermal convection pathways in unprecedented detail for this system and helps identify prospective regions for future geothermal exploration. 3-D imaging of both the Corbetti's magmatic and associated geothermal systems provides key information for the quantitative evaluation of Corbetti's geothermal energy potential and for the assessment of potential volcanic risks.}, keywords = {Africa; hydrothermal system; magnetotellurics; Continental tectonics: extensional; magma genesis and partial melting}, year = {2024}, eissn = {1365-246X}, pages = {1764-1781} } @article{MTMT:34556846, title = {Magmatic priming of a phreatic eruption sequence: the 2012 Te Maari eruptions at Mt Tongariro (New Zealand) imaged by magnetotellurics and seismicity}, url = {https://m2.mtmt.hu/api/publication/34556846}, author = {Heise, Wiebke and Bannister, Stephen and Williams, Charles A and McGavin, Peter and Caldwell, T Grant and Bertrand, Edward A and Usui, Yoshiya and Kilgour, Geoff}, doi = {10.1093/gji/ggae022}, journal-iso = {GEOPHYS J INT}, journal = {GEOPHYSICAL JOURNAL INTERNATIONAL}, volume = {236}, unique-id = {34556846}, issn = {0956-540X}, abstract = {Magnetotelluric data from Mount Tongariro have been analysed using an unstructured tetrahedral finite-element inversion code that incorporates topography, which was not included in previous analysis of these data. Incorporating topography adds information, which stabilizes the resistivity inversion modelling, and for the first time allows details of the shallow hydrothermal system and its relationship with the underlying magmatic system to be resolved. Specifically, an electrically conductive zone between 4 and 12.5 km depth marks the underlying magmatic system, which is shown to directly connect via conductive pathways to the area where the most recent phreatic eruptions at Tongariro occurred in 2012. The resultant phreatic eruptions in 2012 August and November showed no new magmatic component to the eruption deposits. Nevertheless, by combining the magnetotelluric resistivity image with relocated seismicity, we can see that seismicity (a proxy for magma ascent) migrated from the top of the magmatic system into the hydrothermal system in the months preceding these eruptions. Magmatic interaction with the extant hydrothermal system likely caused the over pressurization for the phreatic eruption. This work highlights the utility of combining geophysical methods and petrological data to constrain phreatic eruption processes.}, year = {2024}, eissn = {1365-246X}, pages = {1848-1862} } @article{MTMT:35495423, title = {Anomalously fertile subcontinental lithospheric mantle beneath the intracontinental Canning Basin, Western Australia}, url = {https://m2.mtmt.hu/api/publication/35495423}, author = {Moro, P. S. and Aitken, A. R. A. and Kohanpour, F. and Jessell, M. W.}, doi = {10.1093/gji/ggae258}, journal-iso = {GEOPHYS J INT}, journal = {GEOPHYSICAL JOURNAL INTERNATIONAL}, volume = {239}, unique-id = {35495423}, issn = {0956-540X}, abstract = {Many intracontinental basins form as broad depressions through prolonged, slow subsidence of the continental lithosphere. Such long-lived basins can record lithospheric processes over hundreds of millions of years, serving as important archives of lithospheric evolution. Since continental amalgamation in the Mesoproterozoic, the lithosphere beneath the intracontinental Canning Basin has been subject to several tectonic events, with extensive crustal reworking evidenced through different upper crust data sets. However, knowledge of the structure of the subcontinental lithospheric mantle is lacking. As a consequence, understanding the coupled evolution between surface and deep lithospheric processes, crucial to resolving basin formation, development and survival, remains problematic. Here, we combine geochemical, geophysical and petrophysical data within a thermodynamic modelling framework to determine the thermochemical properties, rheology, density and seismic structure of the lithospheric and sublithospheric mantle beneath the Canning Basin. The results indicate a thick, rigid lithosphere with a maximum thickness of 185 km and strength of ca. 1 x 1013 Pa m, and an anomalously Fe-enriched subcontinental lithospheric mantle with a Mg# of 88.6. This mantle structure is not consistent with pre-collisional fragments or a Precambrian collisional setting and may reflect magmatic refertilization during high-volume mafic magmatic events. Potential candidate events are the similar to 1070 Ma Warakurna, similar to 825 Ma Gairdner and similar to 510 Ma Kalkarindji Large Igneous Provinces. The youngest of these is temporally and spatially correlated with and therefore interpreted to have influenced the Canning Basin formation. We propose that refertilization caused a negatively buoyant subcontinental lithospheric mantle and prolonged subsidence and preservation of the basin, while the strong lithosphere ensured lithospheric stability and longevity.}, keywords = {continental lithosphere; crustal evolution; heat flow; thermal structure; VELOCITY STRUCTURE; THERMOMECHANICAL MODELS; Gravity anomalies and Earth structure; Large Igneous Province; Oceanic lithosphere; Composition and structure of the mantle; Reference model; Intra-plate processes; ELASTIC THICKNESS}, year = {2024}, eissn = {1365-246X}, pages = {769-797} }