Article
Geosciences, Multidisciplinary
Dillon A. Brown, Martin Hand, Laura J. Morrissey
Summary: The study provides evidence of high pressure metamorphism along the eastern margin of Tasmania, with zircon analysis indicating eclogite formation during the Middle Cambrian and older Mesoproterozoic ages. Mineral compositions, element concentrations, and temperature data reveal the growth history and geological evolution of the eclogites.
Article
Geochemistry & Geophysics
Matthew F. Hardman, Thomas Stachel, D. Graham Pearson, Erick J. Cano, Richard A. Stern, Zachary D. Sharp
Summary: The origin of eclogites in cratonic mantle roots has long been debated. In a classic kimberlite locality in South Africa, two types of eclogites with contrasting features have led to different genetic models. A new study of 63 eclogite xenoliths from the area identified two types: Type I likely originating from metamorphosed basaltic-picritic lavas or gabbroic cumulates from oceanic crust, and Type II possibly derived from low-pressure clinopyroxene-bearing oceanic cumulates formed from melts more depleted in incompatible elements than normal mid-ocean ridge basalt.
JOURNAL OF PETROLOGY
(2021)
Article
Geosciences, Multidisciplinary
Xin Dong, Zeming Zhang, Zuolin Tian, Yaoling Niu, Liangliang Zhang
Summary: The high-pressure eclogites in the central Himalaya provide insights into the metamorphism and exhumation history of crustal material beneath the Tibetan plateau. Through the analysis of zircon and titanite U-Pb ages, bulk-rock and mineral compositions, and zircon Hf isotope data, the study reveals the evolution of these eclogites, from peak HP eclogite-facies metamorphism to later retrograde metamorphism. The findings suggest a long-lived burial and slow exhumation process of the Indian continental crust since the initial Indo-Asia collision at around 55 Ma.
Article
Geology
Xiaoli Li, Lifei Zhang, Thomas Bader
Summary: This study provides a detailed petrological analysis of eclogite samples from the Shirokaya Salma locality in the Belomorian Province, Russia, shedding light on the rock composition and metamorphic history. The results indicate that the rocks experienced metamorphic evolution in eclogite and granulite facies, with multiple episodes of high-temperature metamorphism.
JOURNAL OF METAMORPHIC GEOLOGY
(2021)
Article
Geosciences, Multidisciplinary
Stephen Collett, Karel Schulmann, Pierig Deiller, Pavla Stipska, Vit Peresty, Marc Ulrich, Yingde Jiang, Luc de Hoym de Marien, Jitka Mikova
Summary: This article investigates the high-pressure and high-temperature metamorphism during the Mid-Devonian period in the Variscan Orogeny, focusing on the geological characteristics of the Marianske Lazne Complex (MLC). The unique position of MLC at the base of its original upper plate is highlighted. The study reveals that both MLC and the upper plate developed above a relatively unaltered Neoproterozoic lithospheric mantle, which is important for reconstructing the original architecture of the Variscan terranes.
GEOSCIENCE FRONTIERS
(2022)
Article
Geochemistry & Geophysics
Alanielson Ferreira, Gary Stevens, Elton L. Dantas, Reinhardt A. Fuck, Ticiano J. S. dos Santos, Marcel V. S. Leandro
Summary: Eclogites provide important evidence for understanding the geological processes during high-pressure to ultra-high-pressure metamorphism. The different groups of retrogressed eclogites studied in this article have distinct origins and mineral compositions, highlighting the complex geological history of the deep crust.
Article
Geochemistry & Geophysics
Irene Novo-Fernandez, Ricardo Arenas, Christian de Capitani, Manuel Francisco Pereira, Ruben Diez Fernandez, Sonia Sanchez Martinez, Antonio Garcia-Casco
Summary: The Cubito-Moura Unit is a high-P metamorphic succession in the southern Ossa-Morena Complex, affected by a high-P, low to intermediate-T metamorphic event during Late Devonian times. The lithostratigraphy and tectonothermal evolution of this unit are similar to other units in the Iberian, Armorican and Bohemian massifs, forming a single Late Devonian high-P, low to intermediate-T metamorphic belt during the Variscan Orogeny.
Article
Geosciences, Multidisciplinary
Rainer Altherr, Stefan Hepp, Hans Klein, Michael Hanel
Summary: In the Variscan Schwarzwald region, metabasic rocks are interrelated with plagioclase-biotite gneisses, suggesting a derivation from an active plate margin and association with island-arc tholeiites, back-arc basin basalts, or calc-alkaline basalts. The age of Variscan high-pressure/high-temperature metamorphism is older than 333 Ma.
INTERNATIONAL JOURNAL OF EARTH SCIENCES
(2021)
Article
Geochemistry & Geophysics
G. Cruciani, M. Franceschelli, R. Carosi, C. Montomoli
Summary: This study investigates micaschists in the southeastern sector of the Posada-Asinara Shear Zone in the Axial Zone of the Sardinia Variscan chain to reconstruct their metamorphic evolution and P-T history. The micaschists experienced polyphase ductile deformation and are characterized by abundant garnet crystals with strong compositional zoning. The P-T path of the micaschists is determined to be clockwise and consists of two separate stages.
Article
Geosciences, Multidisciplinary
Yunfei Ren, Danling Chen, Haijie Wang, Xiaohui Zhu, Bowen Bai, Hongxi Kong, Zhixiong Wu
Summary: The fate of overriding plate material in subduction channels remains unknown. This study shows that some eclogites in the North Qaidam UHP Metamorphic Belt originated from the overriding plate, unlike the eclogites from the subducted plate. The results reveal that the overriding plate material can reach mantle depths of at least 85 km in the subduction channel and exhumed along with other slices from the subducted slab.
JOURNAL OF ASIAN EARTH SCIENCES
(2022)
Article
Geochemistry & Geophysics
Ruihong Chang, Franz Neubauer, Yongjiang Liu, Johann Genser, Sihua Yuan, Qianwen Huang, Weimin Li, Shengyao Yu
Summary: The Austroalpine eclogite-bearing Sieggraben Complex is a subducted and then exhumed fragment of the continental rift, which led to the formation of the Meliata oceanic basin. The study of the complex provides valuable insights into the age, geochemical characteristics and origin of the rocks in the complex. These results contribute to a better understanding of the tectonic evolution of the region and the formation of the Meliata oceanic lithosphere.
Article
Geosciences, Multidisciplinary
Xiao-Dong Wang, Lin Ding, Deng Zeng, Ya-Hui Yue, Ling-Ping Yang, Zhe-Jun Wang, Lu-An Xiao, Chao Wang
Summary: The North Qaidam ultrahigh-pressure metamorphic belt (NQUB) is characterized by the widespread occurrence of eclogites, the protolith nature of which is still a matter of debate. This study presents new zircon LA-ICP-MS U-Pb ages, whole-rock geochemistry, and Sr-Nd isotopic data for the Yuka and Dulan eclogites in the NQUB. The zircon U-Pb dating results indicate protolith and metamorphic ages of 831-809 Ma and 439-433 Ma, respectively. Based on distinct geochemical characteristics, the samples can be classified into high-Ti/Y type (Group 1) and low-Ti/Y type (Group 2 and Group 3) eclogites. The Group 1 eclogite protoliths show geochemical similarities with oceanic island basalts and likely originate from garnet-spinel peridotite mantle sources.
PRECAMBRIAN RESEARCH
(2023)
Article
Geology
Chen AnPing, Zhang HongFu
Summary: Slab subduction and exhumation are crucial in plate tectonic theory and solid earth science. Decoding the P-T-t path of high pressure-ultrahigh pressure metamorphic rocks is important for understanding the tectonic evolution of subduction/collision orogens. Petrographic observation, mineral composition analysis, and geochronology methods are applied to decipher the metamorphic ages and conditions.
ACTA PETROLOGICA SINICA
(2023)
Article
Geosciences, Multidisciplinary
Fabrizio Cocco, Alfredo Loi, Antonio Funedda, Leonardo Casini, Jean-Francois Ghienne, Gian Luigi Pillola, Muriel Vidal, Mattia Alessio Meloni, Giacomo Oggiano
Summary: The study of Variscan tectonic units in Sardinia reveals different geodynamic settings and paleogeographic positions during the Ordovician period, with significant differences between the units in terms of tectonic evolution and sedimentary deposits.
INTERNATIONAL JOURNAL OF EARTH SCIENCES
(2023)
Article
Geology
Jonas Vanardois, Francoise Roger, Pierre Trap, Philippe Goncalves, Pierre Lanari, Jean-Louis Paquette, Didier Marquer, Florence Cagnard, Benjamin Le Bayon, Jeremie Melleton, Fabrice Barou
Summary: This study investigates mafic eclogite relics in the Aiguilles-Rouges massif of the Western Alps and suggests that they are remnants of continental lower crust exhumed and juxtaposed with lower-grade migmatites in crust-scale vertical transpressive shear zones.
JOURNAL OF METAMORPHIC GEOLOGY
(2022)
Article
Geosciences, Multidisciplinary
Annamaria Fornelli, Salvatore Gallicchio, Francesca Micheletti, Antonio Langone
Summary: The study of sandstone samples from the Southern Apennines in Italy revealed that the detritus provenance of the Gorgoglione Flysch consisted of metamorphic rocks with abundant granitoids covered by sedimentary rocks, with a volcanic component present. Utilizing U-Pb detrital zircon ages, the provenance area was identified in the northwestern sectors of the Mediterranean area, where the Sardinia-Corsica block plays a fundamental role.
GEOLOGICAL MAGAZINE
(2021)
Article
Geosciences, Multidisciplinary
Amar Karaoui, Christoph Breitkreuz, Brahim Karaoui, Zakarya Yajioui, Abdelkader Mahmoudi, Alberto Zanetti, Antonio Langone
Summary: The Skoura inlier in the Moroccan High Atlas is composed of thick Precambrian-Paleozoic formations, displaying a volcano-sedimentary succession in the western part near Aguerzega village. The geochemical results from Skoura volcanic rocks reveal a high silica-rich composition with active continental margin signatures. Zircon dating on rhyolitic ignimbrites yielded ages consistent with the lower Ouarzazate Supergroup in the Anti-Atlas and High Atlas.
INTERNATIONAL JOURNAL OF EARTH SCIENCES
(2021)
Article
Geology
Fabrizio Tursi, Pasquale Acquafredda, Vincenzo Festa, Annamaria Fornelli, Antonio Langone, Francesca Micheletti, Richard Spiess
Summary: The formation and evolution of HP mineral assemblages in metagranitoids are influenced by fluid presence during ductile shear under preferential pathways, such as ductile shear zones in the Earth's crust. This study in the Castagna Unit in southern Italy reveals that the mineral assemblages in orthogneisses vary between weakly deformed samples and those within shear zones, with recrystallization induced by fluids during deformation. The mylonitic orthogneisses share the same peak metamorphic conditions as weakly deformed orthogneisses, but with a different equilibrium mineral assemblage stabilized along a fluid-conservative prograde path.
JOURNAL OF METAMORPHIC GEOLOGY
(2021)
Article
Geochemistry & Geophysics
V Basch, A. Sanfilippo, L. Vigliotti, A. Langone, N. Rasul, M. Khorsheed, S. Al Nomani, A. Al Qutub, M. Ligi
Summary: The study of the Red Sea rift system is important for understanding the transition from a continental to an oceanic rift. By analyzing the petrology and geochemistry of rocks from the Arabian-Nubian Shield region in the southern Red Sea rift system, the researchers found evidence of early syn-rift magmatism and its influence on the geodynamic evolution of the region. The results suggest that this early magmatism led to the replacement of continental crust by oceanic gabbroic bodies, which in turn prolonged the rifting stage.
JOURNAL OF PETROLOGY
(2022)
Editorial Material
Geosciences, Multidisciplinary
Richard Spiess, Antonio Langone, Alfredo Caggianelli, Finlay M. Stuart, Martina Zucchi, Caterina Bianco, Andrea Brogi, Domenico Liotta
Summary: By demonstrating the key features of the regional evolution of the Northern Apennines, we have argued for the importance of a scientific approach in understanding the natural processes on Elba Island.
JOURNAL OF STRUCTURAL GEOLOGY
(2022)
Article
Geography, Physical
F. Fanti, P. R. Bell, M. Vavrek, D. Larson, E. Koppelhus, R. L. Sissons, A. Langone, N. E. Campione, C. Sullivan
Summary: The patterns of Late Cretaceous terrestrial vertebrate diversity in North America are primarily explained by biogeographic provincialism influenced by latitude or coastal-inland habitat gradients. This study focuses on filling the gaps in the terrestrial fossil record during the Campanian period, particularly the 'Bearpaw gap'. The research shows that the vertebrate fauna in the Wapiti Formation of west-central Alberta shares similarities with previous deposits in southern Alberta, emphasizing the impact of environmental factors such as coastal proximity. The presence of an endemic lizard and differences in taxon abundance further suggest the influence of latitude and coastal-inland habitat gradients on the taxonomic composition of Late Cretaceous terrestrial faunas.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2022)
Article
Multidisciplinary Sciences
Giacomo Paglietti, Giuseppa Tanda, Rita Teresa Melis, Anna Musinu, Gabriele Cruciani, Marcello Franceschelli, Carla Cannas, Valentina Mameli, Mariano Casu
Summary: An important Bronze Age settlement was discovered in a cave in south-western Sardinia, Italy. The excavation revealed a rare example of domestic use of a cave and provided an opportunity to study the ancient pottery production techniques in a context unaffected by external cultural influences.
Article
Geology
Leonardo Casini, Matteo Maino, Antonio Langone, Giacomo Oggiano, Stefania Corvo, Joan Reche Estrada, Montserrat Liesa
Summary: This study provides detailed research on the migmatization process in the Punta Bianca area of Italy, revealing two main stages of partial melting and their correlation with regional crustal shearing. The results shed light on the evolution history of rock metamorphism in the region, contributing to a better understanding of the geological processes in the area.
JOURNAL OF METAMORPHIC GEOLOGY
(2023)
Article
Geology
Rick Verberne, Hugo W. van Schrojenstein Lantman, Steven M. Reddy, Matteo Alvaro, David Wallis, Denis Fougerouse, Antonio Langone, David W. Saxey, William D. A. Rickard
Summary: The migration of trace elements in rutile is investigated through the study of low-angle boundaries formed by dislocation creep in an omphacite vein. It is found that dislocation cores along these low-angle boundaries are enriched with various trace elements, including Fe and Ca. The role of dislocation microstructures as fast-diffusion pathways should be considered to avoid erroneous interpretations for Ca and Fe.
JOURNAL OF METAMORPHIC GEOLOGY
(2023)
Article
Geochemistry & Geophysics
S. Corvo, M. Maino, S. Piazolo, S. Seno, A. Langone
Summary: The formation of shear zones is crucial for understanding crustal deformation and the evolution of rifted margins. However, there is often a lack of detailed characterization of the compositional and structural patterns of shear zones, leading to poorly constrained models of shear initiation. This study focuses on the Anzola shear zone and reveals the significant pre-existing heterogeneities related to the composition and deformation structures, suggesting that these heterogeneities are preferential loci for strain localization controlling the initiation and development of rift-related structures in the mid to lower crust of passive margins.
Article
Geochemistry & Geophysics
G. Cruciani, M. Franceschelli, R. Carosi, C. Montomoli
Summary: This study investigates micaschists in the southeastern sector of the Posada-Asinara Shear Zone in the Axial Zone of the Sardinia Variscan chain to reconstruct their metamorphic evolution and P-T history. The micaschists experienced polyphase ductile deformation and are characterized by abundant garnet crystals with strong compositional zoning. The P-T path of the micaschists is determined to be clockwise and consists of two separate stages.
Article
Geology
Gabriele Cruciani, Lorenzo Dulcetta, Marcello Franceschelli, Chiara Frassi, Giovanni Musumeci
Summary: The Mt. Filau Orthogneiss is a part of the Sulcis Metamorphic Complex and shows signs of metamorphic peak and partial melting. The P-T conditions suggest the presence of a thermal anomaly in the foreland zone, possibly caused by the tectonic activity of the Tuerredda ductile shear zone.
ITALIAN JOURNAL OF GEOSCIENCES
(2022)
Article
Geosciences, Multidisciplinary
D. Fancello, S. Columbu, G. Cruciani, L. Dulcetta, M. Franceschelli
Summary: This paper presents the geological, archaeological, and touristic potential of the south-western coastal area of Sardinia, Italy. It proposes a seven-stage itinerary, describing and assessing each site based on its geology, archaeological sites, and touristic attractions. The study highlights the high potential and importance of this area for scientific, educational, and touristic purposes.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Ecology
Giulia Piazza, Valentina A. Bracchi, Antonio Langone, Agostino N. Meroni, Daniela Basso
Summary: This study investigates the influence of growth rate and temperature on the B/Ca ratio in coralline algae. The findings provide valuable insights for reconstructing surface ocean pH and atmospheric pCO(2) using B/Ca as a proxy.
Article
Mineralogy
Enrico Cannao, Massimo Tiepolo, Giulio Borghini, Antonio Langone, Patrizia Fumagalli
Summary: The recycling of volatile and incompatible elements throughout Earth's history is crucial for the chemical evolution of the lithosphere. Amphiboles play a key role in this process and experiments show that factors like oxygen fugacity and chlorine content can affect the partitioning of trace elements. Changes in amphibole structure related to Cl incorporation in the O(3) site contribute to observed variations in element distribution.
EUROPEAN JOURNAL OF MINERALOGY
(2022)
