Journal of Geodynamics最新文献

{"title":"Slab tear and rotation imaged with core-refracted shear wave anisotropy","authors":"Laura Petrescu ,&nbsp;Andrei Mihai ,&nbsp;Felix Borleanu","doi":"10.1016/j.jog.2023.101985","DOIUrl":"10.1016/j.jog.2023.101985","url":null,"abstract":"<div><p>We investigate the complex flow field around the Vrancea slab in Romania, a steeply sinking seismogenic lithospheric block that experienced lateral tear-off and possible rotation. The Vrancea slab is located beneath the South-East Carpathians and generates frequent seismicity despite its remote location from active collisional boundaries. We analyse core-refracted shear wave (SKS) splitting recorded by permanent broadband seismic stations from the Romanian Seismic Network for periods up to 10 years, and compare our results with seismic tomography of the upper mantle. We identify several stations with large backazimuthal variations of SKS fast axis polarization and delay times both in the slab hinge zone, the back-arc and the circum-slab region, indicating complex mantle deformation patterns. To investigate the effect of a two-level rotated slab we invert SKS waveforms using cross-convolutional misfit combined with a neighbourhood search algorithm to model two layers of anisotropy. In the shallow mantle, anisotropy aligns with the upper slab strike and reorients along the strike of the lower slab at depths below the hinge zone. In the back-arc trench-perpendicular anisotropy switches to trench-parallel, due to the recent retreat and roll-back of the slab. Our results have important implications for understanding SKS interference from subducted slab fragments and provide evidence of the recent retreat, break-off and rotation of two Vrancea slab levels sinking into the upper mantle.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"157 ","pages":"Article 101985"},"PeriodicalIF":2.3,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43395835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gravimetric inversion and three-dimensional geological modelling of the Piquiri Syenite Massif, southern Brazil","authors":"Victor Soares Cardoso ,&nbsp;Maria de Fátima Bitencourt ,&nbsp;Jairo Francisco Savian ,&nbsp;Robson dos Santos Aquino ,&nbsp;Cristiane Butori Rivera","doi":"10.1016/j.jog.2023.101988","DOIUrl":"https://doi.org/10.1016/j.jog.2023.101988","url":null,"abstract":"<div><p>The Pelotas Batholith corresponds to the eastern margin of the Dom Feliciano Belt in southernmost Brazil. It comprises multiple intrusions formed by successive tectonic-magmatic processes during the Brasiliano / Pan-African Cycle. One of these intrusive igneous bodies is the Piquiri Syenite Massif (PSM), recently described as a multi-intrusive body formed by three successive pulses, dated by LA-MC-ICP-MS (U-Pb in zircon), with the oldest pulse located at the margins and the youngest in the centre of the intrusion. Pulse 1 (609.3 ± 1.5 Ma) comprises fine- to medium-grained equigranular syenite to quartz syenite and alkali-feldspar quartz syenite, with colour index M′15–30. Pulse 2 (603.4 ± 3.9 Ma) comprises medium- to coarse-grained equigranular alkali-feldspar syenite and alkali-feldspar quartz syenite, with colour index M′ 5–15 and fragments of Pulse 1 varieties. Pulse 3 (588.8 ± 3.1 to 583.2 ± 1.8)comprises medium- to coarse-grained inequigranular quartz syenites, with colour index M′ 2–10, containing fragments of pulses 1 and 2 varieties. As defined by the AMS data, the PSM magnetic fabric is concordant with the magmatic fabric, parallel to the outer edges of the body, dipping towards the centre. However, the construction and emplacement of the body have been the subject of different interpretations. The main objective of this work is to relate the general morphology of the massif and the behaviour of the pulses within the massif with the processes of formation and ascent of the magmas that have built it. For this, terrestrial geophysical surveys were carried out to obtain gravimetric data, with which the Bouguer Anomaly map was generated. Modelling by gravimetric inversion was carried out in nine profiles using tools from the Oasis Montaj software, which was the basis for constructing a three-dimensional geological model using the Leapfrog Geo software. Associating the geological model with the magmatic and magnetic foliations, including the magnetic lineation, it was possible to determine a change in behaviour between the youngest and the two oldest pulses related to the ascension process. In addition, the body’s general shape, with the greatest depths located in the eastern region, allowed us to relate the rise of magma to a structure in the region.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"158 ","pages":"Article 101988"},"PeriodicalIF":2.3,"publicationDate":"2023-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50191980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gravimetric inversion and three-dimensional geological modelling of the Piquiri Syenite Massif, southern Brazil","authors":"Victor Soares Cardoso, Maria de Fátima Bitencourt, J. Savian, Robson dos Santos Aquino, Cristiane Butori Rivera","doi":"10.1016/j.jog.2023.101988","DOIUrl":"https://doi.org/10.1016/j.jog.2023.101988","url":null,"abstract":"","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"1 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54756842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Otolaryngology residency program factors associated with female resident representation.","authors":"Julia E Canick, James C Campbell, Charles R Woodard, Lars J Grimm, Alissa M Collins","doi":"10.1002/wjo2.110","DOIUrl":"10.1002/wjo2.110","url":null,"abstract":"<p><strong>Objective: </strong>Female representation in the field of otolaryngology is lacking. Residency is the first point at which medical school graduates specialize in a chosen field and thus represents an opportunity to recruit and train more female otolaryngologists. This study sought to identify program factors associated with greater female representation among resident physicians.</p><p><strong>Methods: </strong>Departmental websites of all 124 otolaryngology residency programs in the United States and Puerto Rico were examined for a list of residents. For programs with a resident roster available, the genders of residents, faculty, program directors, and chairpersons were recorded. Location and city population for each program was also recorded, as was female resident representation. Programs were compared using Pearson Chi-squared univariate tests.</p><p><strong>Results: </strong>1,632 residents and 2,605 faculty were included in the analysis of 109 programs. The median female resident representation was 40%. Programs with larger faculty sizes, more female faculty, and urban location were associated with an above-median female resident representation. Programs with a larger residency cohort approached significance regarding above-median female resident representation. Higher female faculty representation, program director gender, chairperson gender, and US region were not associated with variation in female resident representation.</p><p><strong>Conclusions: </strong>Greater female otolaryngology residency representation was associated with programs having an urban location and greater numbers of female and total faculty. It was also likely that a larger resident cohort size may affect female resident representation. The proportions of female faculty, program director, and chairperson gender, as well as the US region, were not associated with variation in female resident gender representation.</p>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"10 1","pages":"7-11"},"PeriodicalIF":0.0,"publicationDate":"2023-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10979041/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75591288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early postseismic deformation of the 2018 Lombok, Indonesia, earthquake sequence constrained by GPS data","authors":"Risya Fauziyyah ,&nbsp;Endra Gunawan ,&nbsp;Sri Widiyantoro ,&nbsp;Irwan Meilano ,&nbsp;Syamsuddin","doi":"10.1016/j.jog.2023.101971","DOIUrl":"10.1016/j.jog.2023.101971","url":null,"abstract":"<div><p>Global Positioning System (GPS) stations in Lombok, Indonesia showed postseismic displacement following the 2018 Lombok earthquake sequence which occurred on 28 July 2018 (<em>Mw</em> 6.4), 5 August 2018 (<em>Mw</em> 6.9), 9 August 2018 (<em>Mw</em> 5.9), and the 19 August 2018 (<em>Mw</em> 6.3 and <em>Mw</em> 6.9). This research has investigated the contribution of afterslip and viscoelastic relaxation during the one-month period after the mainshock on 19 August 2018. This study utilizes continuous GPS data available from 20 August 2018–19 September 2018. The analysis reveals that the afterslip was distributed at the shallower portion of the fault, complementary to the deeper coseismic slip of the mainshock. Viscoelastic relaxation, involving a gravitational Maxwell viscoelastic response with viscosity of 9.0 × 10¹⁷ Pa s, was estimated. This research also found that the depth of elastic upper crust in this region is 50 km. Observations made during the one-month period after the mainshock revealed that afterslip was responsible for most of the ongoing postseismic deformation. Although the viscoelastic relaxation contributed only insignificantly during the one-month period, this research shows that viscoelastic relaxation is expected to increase with time.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"156 ","pages":"Article 101971"},"PeriodicalIF":2.3,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43051411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polyphase tectonics in the central Salzkammergut (Northern Calcareous Alps, Austria): An updated interpretation","authors":"Nicola Levi","doi":"10.1016/j.jog.2023.101973","DOIUrl":"10.1016/j.jog.2023.101973","url":null,"abstract":"<div><p>The Northern Calcareous Alps (NCA) (Austria) consist of detached Austroalpine covers, comprising mainly Permian evaporites and Triassic-Jurassic carbonates, topped by unconformable clastic sediments (Gosau Basin, Late Cretaceous-Eocene). The NCA experienced a polyphase deformation during the Eoalpine phase (Jurassic? mid-Cretaceous) followed by post-Eocene transpressive collisional tectonics. In the study area, the oldest regional structure is the Eoalpine NW-ward thrusting of the Dachstein Unit over the Hallstatt Unit. During the Eocene-Oligocene the dextral WNWENE Wolfgangsee fault developed between Osterhorn and Höllengebirge Units. The top-to-N phase followed (Oligocene?-Early/Mid. Miocene), related to the final emplacement of the Tirolic Units on the Bajuvaric and Rheno-Danubian Flysch, which in the Höllengebirge Unit resulted into intense thrusting and folding related to the Schafberg thrust. In the Middle Miocene the development of the Königsee-Lammertal-Traunsee (KLT) sinistral fault led to the major structures in the area. Two stepped strike-slip sectors (SSW-NNE) and (SW-NE/N-S) delimited a restraining bend, where the WNW-ESE Nussensee thrust and the Weissenbach anticline were formed. This deformation history disagrees with some of the available geodynamic models for the area, providing instead fundamental constrains for the Adria paleogeography and the onset of thrusting in the NCA.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"156 ","pages":"Article 101973"},"PeriodicalIF":2.3,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41562292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A personal tribute to Vladislav Babuška","authors":"Robert Cooper Liebermann","doi":"10.1016/j.jog.2023.101976","DOIUrl":"10.1016/j.jog.2023.101976","url":null,"abstract":"<div><p>For the past half century, I have been fortunate in maintaining collaborations with Czech scientists in the Czech Republic (formerly Czechoslovakia) from the Geofyzikálníústav-GFU (Institute of Geophysics) of the Československá Akademie Věd-ČSAV (Czechoslovak Academy of Sciences). These collaborations have included my exchange visits to Prague (Praha) and convening international workshops in 1976, 1986 and 1996 in castles used by the ČSAV as well as visits by Czech colleagues to Stony Brook University. This tribute is in memory of my dear friend and colleague Vladislav Babuška.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"156 ","pages":"Article 101976"},"PeriodicalIF":2.3,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49519023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiple phases of deformation that shaped the southern Central Andes (36.5°S) from crosscutting relationships with Cenozoic retroarc magmatism","authors":"Pablo Borghi ,&nbsp;Lucas Fennell ,&nbsp;Ricardo Gómez Omil ,&nbsp;Andrés Folguera","doi":"10.1016/j.jog.2023.101970","DOIUrl":"10.1016/j.jog.2023.101970","url":null,"abstract":"<div><p>The Southern Central Andes developed though a complex succession of magmatic and deformational episodes, which after more than a century of studies, are still the subject of intense debate. One of the main controversies lies in the ambiguity regarding whether there was a single contractional phase in the Neogene or whether there were multiple contractional phases distributed over the last ∼110 My. We present 33 new K/Ar ages obtained from retroarc subvolcanic intrusives and lava flows and document their crosscutting relations with the host rock strata. These data enabled us to constrain the deformation's timing in several contractional structures along the eastern slope of the southern Central Andes ∼36.5°S. In the hinterland, the timing of compressional deformation has been constrained to the following: between Late Cretaceous and late Miocene age determined by Neogene dikes crosscutting Mesozoic folded strata; pre to syn-late Miocene determined by dikes intruded in the axial surfaces of small anticlines; and post-early Oligocene determined by folded sills. In the foreland, the timing of compressional deformation has been constrained to between the Late Cretaceous and early Oligocene by dikes crosscutting pre-deformed strata; to the post-Oligocene by folded sills; to the pre- and post-middle Eocene by Eocene to Miocene dikes crosscutting older folded strata; and to the post to syn-middle Miocene by folded lava flows. We conclude that two pre-Neogene and one Neogene contractional phases, and various retroarc magmatic events have affected this segment of the retroarc. We discuss our observations in relation to previous proposals, separating the tectonic evolution of the area into six tectonic scenarios from the late Early Cretaceous to the present.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"156 ","pages":"Article 101970"},"PeriodicalIF":2.3,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44889052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Remote sensing data applied to the reconstruction of volcanic activity in the Valley of the Volcanoes, Central Volcanic Zone, Peru","authors":"Andrzej Gałaś ,&nbsp;Paulina Lewińska ,&nbsp;Rigoberto Aguilar ,&nbsp;Łukasz Nowak","doi":"10.1016/j.jog.2023.101972","DOIUrl":"10.1016/j.jog.2023.101972","url":null,"abstract":"<div><p>The Valley of the Volcanoes is a representative area of the extension of the Quaternary Andahua Group with which it overlaps. Some of its eruption centres have renewed activity after more than 500 ka. Recreating the history of the Valley of the Volcanoes activity required satellite data and remote sensing-based methods for visualizing the terrain surface. We used SRTM 30 m DEM, channels 4, 3, 2; Landsat 7, 8 and ASTER images. We verified and refined the obtained data during field works using Structure-from-Motion (SfM) to create of 3D models of selected geoforms. Satellite data allowed us to create: Red Relief Image Map, Topographic Position Index and Normalised Difference Vegetation Index (NDVI) maps. In the Valley of the Volcanoes, we analysed 12 lava fields with a total area of 326.3 km² and a volume of approx. 20 km³. We determined the number of eruption centres that yielded to 41 small lava domes and 23 scoria cones. This domes are classified as monogenetic volcanoes, however five of them can be considered polygenetic e.g. Puca Mauras. We used NDVI to develop chronology map of lavas. This allowed us to extract same-age eruption centres and associated volcanoes that represent the same eruptive time phase connected by fault lines: first generation (0.5–0.27 Ma) NW-SE and NE-SW, second (Pleistocene/Holocene) NNW-SSE and third (Holocene-Historical) again NW-SE and NE-SW. We carried out the reconstruction of the central part of the Valley of the Volcanoes because only there repeated phases of volcanic activity can be inferred with remote sensing and geological mapping. The results of this study led us to indicate that this area should be observed since it is very likely that future eruptions will occur.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"156 ","pages":"Article 101972"},"PeriodicalIF":2.3,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45423973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New structural analysis in North Dobrogea - a key region to unravel the tectonics of the Black Sea back-arc basin during the Mesozoic","authors":"Yevgeniya Korniyenko-Sheremet ,&nbsp;Aline Saintot ,&nbsp;Antoneta Seghedi ,&nbsp;Tom McCann ,&nbsp;Marc Sosson","doi":"10.1016/j.jog.2023.101969","DOIUrl":"10.1016/j.jog.2023.101969","url":null,"abstract":"<div><p>High-resolution structural analysis of stratigraphically-controlled units within North Dobrogea (ND), based on fieldwork and the production of new cross-sections as well as a reconstruction of the Mesozoic paleo-stress regimes, has resulted in a revision of the tectonic events across the region as well as demonstrating the significance of tectonic inheritance. The observed structures are closely related to the major strike-slip faults of the Teisseyre-Tornquist Zone (TTZ) a lithospheric structure active during the early and middle Mesozoic. The significance of this zone has been underestimated in previous kinematic reconstructions examining the opening of the continental back-arc basin of the Black Sea. Integrating the present results with existing knowledge on the tectonic evolution of the Black Sea, suggests a new conceptual kinematic model for further testing, one that involves movement of the continental fragment of Moesia NW along the TTZ during the early and middle Mesozoic. Such a displacement would represent the westernmost occurrence of the Cimmerian orogeny in the region of the western Black Sea. The escape of Moesia to the NW could possibly explain the polyphase extension of the western Black Sea crust, which developed on the continental Eurasian Plate as a back-arc basin due to the N-directed subduction of Tethys.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"156 ","pages":"Article 101969"},"PeriodicalIF":2.3,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42015375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}