Article
Geochemistry & Geophysics
Benjamin E. Cohen, Darren F. Mark, William S. Cassata, Lara M. Kalnins, Martin R. Lee, Caroline L. Smith, David L. Shuster
Summary: Research found that the shergottites have a wide range of ages, with statistically robust Ar-40/Ar-39 isochron ages ranging from 161+/-9 Ma to 540+/-63 Ma, consistent with other dating methods. These data indicate that, despite experiencing shock metamorphism, the shergottites were sourced from the youngest volcanoes on Mars.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Geography, Physical
H. S. Monteiro, P. M. Vasconcelos, K. A. Farley, C. L. Mello, F. T. Conceicao
Summary: Distinctive sediments containing quartz, kaolinite, detrital and authigenic hematite and goethite are present along the Atlantic coast of Brazil. These sediments represent a significant period of erosion and weathering, with strong influence from biologically driven weathering reactions. The ages of detrital and authigenic goethites and hematites suggest that sedimentation occurred between 26-20 million years ago. Furthermore, (U-Th)/He geochronology indicates a period of tropical climate and abundant vegetation dominating the coast of Espirito Santo since the Pliocene.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2022)
Article
Multidisciplinary Sciences
Jennifer E. Thines, Ingrid A. Ukstins, Corey Wall, Mark Schmitz
Summary: The silicic volcanism in the Afro-Arabian large igneous province has produced some of the largest volcanic eruptions on Earth, occurring within a short timeframe but not causing major global environmental changes. High-precision dating shows the highest known long-term volumetric extrusive rate of silicic volcanism on Earth, providing valuable insights into the tempo of large-volume magma generation and eruption.
NATURE COMMUNICATIONS
(2021)
Review
Geosciences, Multidisciplinary
Aubreya Adams
Summary: The Cameroon Volcanic Line (CVL) of west Africa, which exhibits asynchronous volcanism along the line, poses challenges to common models of mantle processes and volcanic system genesis. Geophysical studies have been conducted to understand the complex geology of the region and potential geodynamic models for the CVL formation.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
B. Eid, F. Lhuillier, S. A. Gilder, J. A. Pfaender, E. F. Gebru, D. Assbichler
Summary: The research findings from investigating the eruption history of the Ethiopia-Yemen Traps revealed that the local extrusion rate of the Afar plume head exceeded the average rate of the entire plume. The high titanium concentrations in the basalts suggest a faster local extrusion rate near the Afar plume axis.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geochemistry & Geophysics
Allan Silva Gomes, Paulo Marcos Vasconcelos, Isabela de Oliveira Carmo
Summary: The presence of secondary phases in volcanic rocks and intrusive units may pose challenges for high resolution 40Ar/39Ar geochronology. Acid treatment is used to remove alteration products, but it has minimal impact on the accuracy of age determinations. Effective separation of atmospheric and radiogenic gases can successfully mitigate deleterious effects associated with alteration phases.
Article
Geochemistry & Geophysics
C. Antoine, R. A. Spikings, D. Miletic, J. S. Marsh, S. P. Gaynor, U. Schaltegger
Summary: The extrusive component of the Karoo Large Igneous Province, the Drakensberg Continental Flood basalts of South Africa and Lesotho, is mainly composed of altered tholeiitic basalts without suitable uraniferous mineral phases for high-precision dating. Multiple techniques were used to study the plagioclase in the lavas, revealing two distinct generations of plagioclase and different alteration phases. The study explains the inaccuracies in previous dating results and provides the most accurate age for the entire lava stack.
Article
Geochemistry & Geophysics
Edgar A. Cortes-Calderon, Ben S. Ellis, Chris Harris, Darren F. Mark, Julia Neukampf, John A. Wolff, Peter Ulmer, Olivier Bachmann
Summary: Through the study of the Fataga Group on Gran Canaria, it is found that it is a new location of low-delta O-18 felsic rocks, and the main magmatic process is fractional crystallization at shallow depths. The volcanic caldera and fault system also play a role in the assimilation of hydrothermally altered rocks.
JOURNAL OF PETROLOGY
(2022)
Article
Geology
Timothy Paulsen, John Encarnacion, Anne M. Grunow, Victor A. Valencia, Mark E. Pecha, Jeffrey Benowitz, Paul Layer
Summary: New age data from the Queen Maud Mountains in the Ross orogenic belt of Antarctica reveal that plutonism primarily occurred during the Cambrian to Ordovician periods, with polymodal age distributions consistent with regional magmatic flare-ups along the Pacific-Gondwana margin. Deformed plutons indicate deformation during the Cambrian to Ordovician periods, transitioning to post-tectonic magmatism and cooling at around 509-470 Ma. This suggests that the Queen Maud-Horlick Mountains share a similar petrotectonic history with other regions along the Pacific-Gondwana margin, providing new evidence for their tectonic evolution.
INTERNATIONAL GEOLOGY REVIEW
(2021)
Article
Geosciences, Multidisciplinary
Erin Heilman, Thorsten W. Becker
Summary: Mantle plumes can play a significant role in the evolution of Earth and plate tectonics, potentially causing the termination of subduction zones and contributing to the complexity of mantle structures. This effect may be particularly relevant for the early Earth and remain relevant in modern times.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geochemistry & Geophysics
P. W. Ball, G. G. Roberts, D. F. Mark, D. N. Barfod, N. J. White, B. H. Lodhia, M. M. Nahdi, S. Garni
Summary: Harrat Rahat is the largest volcanic field in Saudi Arabia and has been active from around 10 Ma to the present day. Recent eruptions at Harrat Rahat have been extensively studied, but the evolution of its oldest lava flows, known as the Shawahit Basalt, is poorly understood. In this study, we collected and analyzed samples from Harrat Rahat, focusing on the Shawahit unit. We found that the volcanic activity at Harrat Rahat was initiated by a mantle plume beneath a thinned lithosphere, and the changes in geochemistry can be attributed to a decrease in melt productivity and contamination.
Article
Geography, Physical
Mirek Groen, Michael Storey
Summary: The age uncertainties of the Greenland ice core timescale are inherently problematic, and radio-isotopic age determination of volcanic ash layers can provide independent verification and improved precision for the older part of the timescale. The study found that the radio-isotopic age is more precise compared to the counted annual ice layers, indicating that the oldest part of the timescale is systematically too young by approximately 740 years. These results provide firmer constraints for testing synchronicity or leads and lags in the late Pleistocene climate system.
QUATERNARY SCIENCE REVIEWS
(2022)
Article
Geochemistry & Geophysics
Antomat A. Macedo Filho, Maria Helena B. M. Hollanda
Summary: The Rio Ceara-Mirim magmatism in NE Brazil during the West Gondwana breakup produced Mesozoic giant arcuate dike swarms. Petrographic, mineralogical, geochemical and isotopic analyses revealed four geochemical groups with distinct compositions and isotopic signatures, indicating their different mantle sources.
Article
Geography, Physical
Khachatur Meliksetian, Iain Neill, Dan N. Barfod, Eilidh J. M. Milne, Emma C. Waters, Gevorg Navasardyan, Edmond Grigoryan, Valerie Olive, Nicholas Odling, Arkady Karakhanian
Summary: The Karkar monogenetic volcanic field in Syunik, SE Armenia, near the country's only geothermal energy test site, erupted fissure-fed trachybasaltic andesite to trachyandesite lavas on a trans-tensional segment of the Pambak-Sevan-Syunik Fault. High-resolution dating suggests a Holocene age for the youngest eruptions, with volcanic activity overlapping with Palaeolithic to Bronze Age human occupation and posing a minor lava inundation hazard. Further geochemical research is needed to understand magma storage depth and timescales, indicating potential for future geothermal energy development in the area.
QUATERNARY GEOCHRONOLOGY
(2021)
Article
Geochemistry & Geophysics
Abdullah Kaygusuz, Cem Yucel, Emre Aydincakir, Mehmet Ali Gucer, Gilles Ruffet
Summary: This study investigates the sources and evolutionary history of Middle Eocene volcanic rocks in the Eastern Pontides region of NE Turkey through whole-rock geochemistry, Sr-Nd isotopic, and 40Ar/39Ar age data analysis. The findings suggest that these volcanic rocks originated from a lithospheric mantle source enriched by fluids derived from subduction, in a post-collisional extensional tectonic setting.
MINERALOGY AND PETROLOGY
(2022)
Article
Geochemistry & Geophysics
Alan Levett, Paulo M. Vasconcelos, Michael M. W. Jones, Llew Rintoul, Anat Paz, Emma J. Gagen, Gordon Southam
Summary: The evolution of iron-rich duricrusts in the Serra Sul de Carajas in Brazil plays a key role in enriching and preserving world-class iron ore deposits. Research shows that various exogenous materials are incorporated into secondary cements within the duricrusts, and microorganisms likely contribute to mineral weathering and biomineralization. The mobility of titanium within the duricrusts and the release of ferrous iron during weathering of magnetite-bearing rocks are also important findings.
Article
Geochemistry & Geophysics
Allan Silva Gomes, Paulo Marcos Vasconcelos, Isabela de Oliveira Carmo
Summary: The presence of secondary phases in volcanic rocks and intrusive units may pose challenges for high resolution 40Ar/39Ar geochronology. Acid treatment is used to remove alteration products, but it has minimal impact on the accuracy of age determinations. Effective separation of atmospheric and radiogenic gases can successfully mitigate deleterious effects associated with alteration phases.
Article
Geochemistry & Geophysics
Peter E. Martin, Kenneth A. Farley, Charles A. Malespin, Paul R. Mahaffy, Kenneth S. Edgett, Sanjeev Gupta, William E. Dietrich, Michael C. Malin, Kathryn M. Stack, Paulo M. Vasconcelos
Summary: Experiments on Mount Sharp in Gale crater on Mars show that the rock layers have been removed over the past billion years, suggesting that Mount Sharp likely formed during the Hesperian period.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Geochemistry & Geophysics
Junjie Zhang, Pengyuan Guo, Pu Sun, Yaoling Niu, Yuanyuan Xiao, Paulo M. Vasconcelos
Summary: This study investigates the origin of early Cretaceous intra-plate alkali basalts from the Western North China Craton (WNCC) and suggests that these rocks originated from partial melting of the lithospheric mantle that experienced melt metasomatism. The geochemical characteristics of these basalts indicate contributions from two different types of metasomatic melts. Additionally, the presence of specific element abundance and isotopic compositions in the basalts suggests a complex origin involving reactions between mantle peridotite and melts of different sources.
Review
Environmental Sciences
Alan Levett, Emma Gagen, Anat Paz, Paulo Vasconcelos, Gordon Southam
Summary: Remediating iron ore mines in Brazil faces a unique challenge of restoring unique rupestrian ecosystems and rare plant species. Developing a substrate similar to iron-rich cap rock and accelerating iron cement formation to stabilize crushed materials, restore hydrology, and revegetate with native species are key elements for successful remediation programs. Understanding biological processes that contribute to canga evolution can lead to environmentally friendly strategies for iron ore mine remediation in the future.
CRITICAL REVIEWS IN ENVIRONMENTAL SCIENCE AND TECHNOLOGY
(2022)
Article
Geology
M. E. Almeida, R. S. C. Nascimento, T. A. Mendes, J. O. S. Santos, M. J. B. Macambira, P. Vasconcelos, S. S. Pinheiro
Summary: The Rio Negro Province in the NW Amazon craton is composed of three domains with different rock types and ages. The province is interpreted as an accretionary orogen formed by a long-lived magmatic arc system, and it has apparent connections with Laurentia and Baltica. The Nd isotope data of the basement rocks provide insights into the mantle sources and crustal contributions.
INTERNATIONAL GEOLOGY REVIEW
(2022)
Article
Geochemistry & Geophysics
Allan Silva Gomes, Paulo Marcos Vasconcelos, Teresa Ubide, Eleonora Maria Gouvea Vasconcellos
Summary: The high-Ti Paranapanema sequence in the Parana Large Igneous Province is characterized by a series of pahoehoe lava flows, some of which contain unique mafic segregation structures. The study of two pegmatite occurrences and their host basalts reveals that the pegmatites are more fractionated and enriched in various elements compared to the enclosing lavas. Additionally, age differences observed in plagioclase phenocrysts from the pegmatites and whole-rock fragments from the enclosing lavas are likely due to hydrothermal alteration rather than differences in crystallization age.
Article
Multidisciplinary Sciences
Matthew R. McCurry, David J. Cantrill, Patrick M. Smith, Robert Beattie, Mary Dettmann, Viktor Baranov, Charles Magee, Jacqueline M. T. Nguyen, Marnie A. Forster, Jack Hinde, Ross Pogson, Helen Wang, Christopher E. Marjo, Paulo Vasconcelos, Michael Frese
Summary: Reduced precipitation in the Miocene caused rainforest ecosystems to contract globally, particularly in Australia where they transformed into shrublands, grasslands, and deserts. The lack of well-preserved fossils has hindered understanding of pre-aridification Australian ecosystems. This study presents an exceptionally well-preserved rainforest biota in New South Wales, Australia, containing a diverse assemblage of microfossils, plants, insects, spiders, and vertebrate remains. These fossils indicate a mesic rainforest surrounding an oxbow lake and suggest shifts in rainforest distributions since the Miocene. The high fidelity of preservation allows for unprecedented insights into Miocene-dominated mesic ecosystems in Australia.
Article
Geochemistry & Geophysics
A. T. Tapu, T. Ubide, P. M. Vasconcelos
Summary: By studying three central volcanoes in eastern Australia, the complexity of magma transport and storage during the waning of hotspot activity is revealed, and it is found that eruptive tempo of volcanism is controlled by mafic influx.
JOURNAL OF PETROLOGY
(2022)
Article
Geology
Matthew J. Campbell, Nick Mortimer, Gideon Rosenbaum, Charlotte M. Allen, Paulo M. Vasconcelos, Hamish J. Campbell
Summary: We revised and clarified the geology of the Brook Street Terrane in the Takitimu Mountains using airborne magnetic and gamma-ray spectrometric survey, and new age determinations. Our findings include the ages of several plutonic suites and their geological relationships with the Takitimu Subgroup, providing further insights into the Early Permian age nature of the latter.
NEW ZEALAND JOURNAL OF GEOLOGY AND GEOPHYSICS
(2023)
Article
Geochemistry & Geophysics
Tommaso Giovanardi, Paulo Cesar Correa da Costa, Vicente A. V. Girardi, Ricardo K. Weska, Paulo M. Vasconcelos, David S. Thiede, Maurizio Mazzucchelli, Anna Cipriani
Summary: This study investigates the geochemical and geochronological characteristics of basalts from the southern Mato Grosso region of Brazil and compares them with other volcanic rocks from the Paraná Magmatic Province. The results suggest that the Alto Diamantino basalts may represent the northwesternmost expression of the Paraná Magmatic Province, and the origin and formation processes of the magmas are still debated.
Article
Geography, Physical
H. S. Monteiro, P. M. Vasconcelos, K. A. Farley, C. L. Mello, F. T. Conceicao
Summary: Distinctive sediments containing quartz, kaolinite, detrital and authigenic hematite and goethite are present along the Atlantic coast of Brazil. These sediments represent a significant period of erosion and weathering, with strong influence from biologically driven weathering reactions. The ages of detrital and authigenic goethites and hematites suggest that sedimentation occurred between 26-20 million years ago. Furthermore, (U-Th)/He geochronology indicates a period of tropical climate and abundant vegetation dominating the coast of Espirito Santo since the Pliocene.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2022)
Article
Multidisciplinary Sciences
K. A. Farley, K. M. Stack, D. L. Shuster, B. H. N. Horgan, J. A. Hurowitz, J. D. Tarnas, J. I. Simon, V. Z. Sun, E. L. Scheller, K. R. Moore, S. M. McLennan, P. M. Vasconcelos, R. C. Wiens, A. H. Treiman, L. E. Mayhew, O. Beyssac, T. V. Kizovski, N. J. Tosca, K. H. Williford, L. S. Crumpler, L. W. Beegle, J. F. Bell, B. L. Ehlmann, Y. Liu, J. N. Maki, M. E. Schmidt, A. C. Allwood, H. E. F. Amundsen, R. Bhartia, T. Bosak, A. J. Brown, B. C. Clark, A. Cousin, O. Forni, T. S. J. Gabriel, Y. Goreva, S. Gupta, S. -E. Hamran, C. D. K. Herd, K. Hickman-Lewis, J. R. Johnson, L. C. Kah, P. B. Kelemen, K. B. Kinch, L. Mandon, N. Mangold, C. Quantin-Nataf, M. S. Rice, P. S. Russell, S. Sharma, S. Siljestrom, A. Steele, R. Sullivan, M. Wadhwa, B. P. Weiss, A. J. Williams, B. V. Wogsland, P. A. Willis, T. A. Acosta-Maeda, P. Beck, K. Benzerara, S. Bernard, A. S. Burton, E. L. Cardarelli, B. Chide, E. Clave, E. A. Cloutis, B. A. Cohen, A. D. Czaja, V. Debaille, E. Dehouck, A. G. Fairen, D. T. Flannery, S. Z. Fleron, T. Fouchet, J. Frydenvang, B. J. Garczynski, E. F. Gibbons, E. M. Hausrath, A. G. Hayes, J. Henneke, J. L. Jorgensen, E. M. Kelly, J. Lasue, S. Le Mouelic, J. M. Madariaga, S. Maurice, M. Merusi, P. -Y. Meslin, S. M. Milkovich, C. C. Million, R. C. Moeller, J. I. Nunez, A. M. Ollila, G. Paar, D. A. Paige, D. A. K. Pedersen, P. Pilleri, C. Pilorget, P. C. Pinet, J. W. Rice, C. Royer, V. Sautter, M. Schulte, M. A. Sephton, S. K. Sharma, S. F. Sholes, N. Spanovich, M. St. Clair, C. D. Tate, K. Uckert, S. J. VanBommel, A. G. Yanchilina, M. -P. Zorzano
Summary: The Perseverance rover has discovered water-altered igneous rocks in the Jezero crater on Mars and found evidence of brine evaporation in the core samples. These samples may be brought back to Earth for further research.
Article
Geosciences, Multidisciplinary
T. J. Crossingham, T. Ubide, P. M. Vasconcelos, K. M. Knesel
Summary: Small-scale continental basaltic fields can erupt suddenly and bring deep undegassed magmas to the surface rapidly. In this study, the volcanic activity, magma origin, and plumbing system architecture of the Hoy lava field in central Queensland, Australia were investigated and compared with large-scale shield volcanoes. The results show that the volcanism in the Hoy lava field has a long duration of approximately 50 million years and magma storage in the mantle depths, which is different from the relatively short duration and crustal magma storage depths of shield volcanoes.
AUSTRALIAN JOURNAL OF EARTH SCIENCES
(2023)
Article
Geography, Physical
Daniela S. De Campos, Hevelyn S. Monteiro, Paulo M. Vasconcelos, Kenneth A. Farley, Alexandre Christofaro Silva, Pablo Vidal-Torrado
Summary: Lithology plays a crucial role in rock weathering, erosion, and landscape evolution. In a unique geomorphological-lithological-climatic setting in Southern Espinhaco Range, Brazil, resistant quartzites acted as a barrier against erosion and facilitated the formation of deep bauxitic weathering profiles. Recurrent mobilization of aluminium and iron within the profiles was mainly driven by mineral dissolution-reprecipitation mediated by bioturbation and organic species influx.
EARTH SURFACE PROCESSES AND LANDFORMS
(2023)