Article
Geochemistry & Geophysics
Delia Rosel, Thomas Zack
Summary: Due to advancements in reaction cell technologies, LA-ICP-MS/MS can now be used to collect extensive Rb-87/Sr-86 and Sr-87/Sr-86 data sets, allowing for the measurement, calculation, and validation of Rb-Sr ages from individual laser spots. This offers potential for provenance studies and the creation of age maps with unprecedented spatial resolution.
GEOSTANDARDS AND GEOANALYTICAL RESEARCH
(2022)
Article
Geochemistry & Geophysics
Alexander Simpson, Sarah Gilbert, Renee Tamblyn, Martin Hand, Carl Spandler, Jack Gillespie, Angus Nixon, Stijn Glorie
Summary: Lu-Hf geochronology is a powerful method for constraining the temporal evolution of geological systems, with traditional methods requiring time-consuming chemical separations and potentially losing the textural context of analysed minerals. In contrast, the in-situ approach offers rapid analysis with high spatial resolution, but is hindered by isobaric interferences of Yb-176 and Lu-176 on Hf-176.
Article
Geochemistry & Geophysics
Shiqiang Huang, Zhaoshan Chang, Kairan Liu, Dieter Garbe-Schoenberg
Summary: The recent development of LA-ICP-MS/MS techniques allows for in situ Rb-Sr dating of micas. This study optimized laser conditions and developed a new data reduction approach to improve the accuracy and precision of Rb-Sr dating. The results demonstrate that this technique is effective for dating mineral deposits and rocks with high spatial resolution and provides a powerful tool for geochronological studies.
GEOSTANDARDS AND GEOANALYTICAL RESEARCH
(2023)
Article
Geosciences, Multidisciplinary
Shitou Wu, Yueheng Yang, Nick M. W. Roberts, Ming Yang, Hao Wang, Zhongwu Lan, Bohang Xie, Tianyi Li, Lei Xu, Chao Huang, Liewen Xie, Jinhui Yang, Fuyuan Wu
Summary: The study on U-Pb geochronology of calcite using LA-ICP-MS is an emerging method with improved sensitivity, resulting in precise measurements of U and Pb isotopes. The optimized instrument parameters allowed for accurate analysis of commonly-used calcite U-Pb reference materials, demonstrating the reliability of the technique in obtaining robust ages. The image-guided approach using LA-ICP-MS elemental mapping proved to be an efficient tool in age determination.
SCIENCE CHINA-EARTH SCIENCES
(2022)
Article
Geosciences, Multidisciplinary
Sherif Mansour, Noriko Hasebe, Akihiro Tamura
Summary: Zircon U-Pb geochronology is a valuable tool for exploring eroded crusts and identifying the components of the Arabian-Nubian Shield. The study of detrital sedimentary rocks in the Somr El-Qaa area reveals three main sources: Pre-Pan-African, Pan-African, and Post-Pan-African, indicating the existence of different geological events in the region.
PRECAMBRIAN RESEARCH
(2023)
Article
Geochemistry & Geophysics
Patrick A. Carr, Emeline Moreira, Leonid Neymark, Marc D. Norman, Julien Mercadier
Summary: Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was used to compare the suitability of different cassiterite materials for U-Pb and Pb-Pb isotope ratio normalization. The estimated excess variance of ages determined by LA-ICP-MS is necessary for realistic uncertainties. Pb-207/Pb-206 ages are advantageous for dating Precambrian cassiterite. Minor bias in Pb-207/Pb-206 ages was observed when using certain reference materials, emphasizing the requirement for uncertainty propagation and comparable reference materials. The use of matrix-matched reference materials is also emphasized for accurate U-Pb age calculations. The LA-ICP-MS U-Pb ages of different cassiterite samples were consistent with their ID-TIMS values.
GEOSTANDARDS AND GEOANALYTICAL RESEARCH
(2023)
Article
Geochemistry & Geophysics
David Chew, Kerstin Drost, Jeffrey H. Marsh, Joseph A. Petrus
Summary: Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) mapping is a rapidly growing field in geosciences, providing spatial information on petrogenesis and ore mineral formation. The technique has diverse applications in forensics, archaeology and biological tissues imaging. Instrumentation advancements now allow precise isotopic analysis and multi-element mapping with high spatial resolution.
Article
Geosciences, Multidisciplinary
Nick M. W. Roberts, Jiri Zak, Frantisek Vacek, Jiri Slama
Summary: Dating fracture-filling calcite with U-Pb geochronology is a useful technique for determining brittle deformation timing, but results may not always directly relate to fault motion. Petrographic and elemental analyses are crucial for interpreting U-Pb data from slickenfibre calcite, as internal textures can be altered by fluid infiltration, leading to variable U and Pb mobilisation. Specifically, the study of slickenfibres on the Ockov thrust in the Lower Palaezoic Prague Basin demonstrates the preservation of external textures and the destruction of primary textures, with potential uncertainties in the interpreted ages.
GEOSCIENCE FRONTIERS
(2021)
Article
Geochemistry & Geophysics
Sherif Mansour, Noriko Hasebe, Ehab Azab, Ashraf Y. Elnaggar, Akihiro Tamura
Summary: The combination of U-Pb and FT double dating using LA-ICP-MS methodology efficiently determines both the crystallization ages and thermo-tectonic history of samples, reducing analytical costs and time, providing a powerful tool for geological dating studies.
Article
Geochemistry & Geophysics
Alicia M. Cruz-Uribe, Grant Craig, Joshua M. Garber, Bence Paul, Cemil Arkula, Claudia Bouman
Summary: Laser ablation tandem mass spectrometry is a growing field for in situ Rb-Sr geochronology. In this study, we used an ESL(TM) imageGEO(TM) 193 excimer laser ablation system coupled to a Thermo Scientific(TM) Neoma(TM) MC-ICP-MS/MS to determine the isotope ratios of Sr-87/Sr-86 and Rb-87/Sr-86 in metamorphic biotite from western Maine. Our results show significant zoning within single spot analyses, suggesting the potential for recording multiple heating, cooling, or fluid-alteration events within small domains in single biotite crystals.
GEOSTANDARDS AND GEOANALYTICAL RESEARCH
(2023)
Article
Geochemistry & Geophysics
Patrick A. Carr, Julien Mercadier, Matthieu Harlaux, Rolf L. Romer, Emeline Moreira, Helene Legros, Michel Cuney, Christian Marignac, Jean Cauzid, Lise Salsi, Andrei Lecomte, Olivier Rouer, Chantal Peiffert
Summary: Wolframite has been proposed as a U/Pb geochronometer for direct dating of W mineralisation events, but its isotopic analysis may be hampered by various factors. In situ U/Pb dating by LA-ICP-MS can provide more accurate results, as demonstrated in this study. The chemical variability and isotopic heterogeneity of wolframite in the French Massif Central highlight the need for pre-screening imaging methods before LA-ICP-MS analyses.
Article
Geochemistry & Geophysics
Nathan Cogne, Kerry Gallagher
Summary: The study compared the multi-spot and single spot methods for uranium determination in fission track dating technique, and found that the multi-spot approach is more accurate and robust in dealing with low track densities and zoned samples. Additionally, it was observed that a single spot measurement can induce overdispersion and a relationship between single grain age and uranium content.
Article
Crystallography
Jialu Gu, Bo Xu, Shu Li, Yi Zhao
Summary: By studying two titanite samples from Mogok, Myanmar, this research provides data on the spectral characteristics and major and trace elements of these samples. The findings suggest that the samples are magmatic-hydrothermal titanites.
Article
Geochemistry & Geophysics
Joao P. A. Silva, Cristiano Lana, Ariela Mazoz, Ian Buick, Ricardo Scholz
Summary: U-Pb Saturn is a new freeware designed for U-Pb LA-ICP-MS data reduction. The software allows easy interaction and visualization of LA-ICP-MS U-Pb datasets, providing fast and reliable data reduction for hundreds of data-points. It offers dynamic graphic interfaces for viewing, evaluating, and plotting U-Pb and Pb-Pb isotope data.
GEOSTANDARDS AND GEOANALYTICAL RESEARCH
(2023)
Article
Geochemistry & Geophysics
Esther Scheiblhofer, Ulrike Moser, Stefan Loehr, Markus Wilmsen, Juraj Farkas, Daniela Gallhofer, Alice Matsdotter Backstrom, Thomas Zack, Andre Baldermann
Summary: The scarcity of well-preserved and directly dateable sedimentary sequences poses a challenge to inferring the Earth's paleo-environmental evolution. By improving the methods for measuring and interpreting the formation ages of glauconite, a mineral with potential for providing absolute stratigraphic ages for sedimentary sequences, researchers have successfully obtained stratigraphically significant ages for glauconite from a Cretaceous shelfal sequence in northern Germany. The study confirms that glauconite, even in mineralogically complex grains, can preserve pristine ages under burial diagenetic conditions, making it a valuable archive for paleo-environmental reconstructions and direct sediment dating.
Article
Geochemistry & Geophysics
Axel S. L. Sjoqvist, Thomas Zack, Denise K. Honn, Ethan F. Baxter
Article
Geology
V van Schijndel, G. Stevens, C. Lana, T. Zack, D. Frei
Summary: The formation and evolution of Palaeoarchaean De Kraalen and Witrivier Greenstone Belts (DKGB and WGB) of the Kaapvaal Craton are poorly understood. This study reports U-Pb ages and Hf isotopic data of zircon and rutile from supracrustal rocks in these areas. The results indicate different protolith and metamorphic ages for the rocks in DKGB and WGB, as well as variations in Hf isotopic compositions.
SOUTH AFRICAN JOURNAL OF GEOLOGY
(2021)
Article
Geochemistry & Geophysics
Alicia M. Cruz-Uribe, F. Zeb Page, Emilie Lozier, Maureen D. Feineman, Thomas Zack, Regina Mertz-Kraus, Dorrit E. Jacob, Kouki Kitajima
Summary: Garnet from an amphibolitized eclogite block in California shows complex growth patterns with similarities in composition between vein and matrix garnet. Major and trace element zoning in garnet reveals multiple growth stages, while oxygen isotope analyses suggest late-stage growth involved interaction with serpentinites.
CONTRIBUTIONS TO MINERALOGY AND PETROLOGY
(2021)
Article
Geology
Darwinaji Subarkah, Morgan L. Blades, Alan S. Collins, Juraj Farkas, Sarah Gilbert, Stefan C. Lohr, Ahmad Redaa, Eilidh Cassidy, Thomas Zack
Summary: Authigenic components in marine sediments play a crucial role in reconstructing past environments. However, determining reliable age constraints and assessing post-depositional processes in Precambrian sequences is challenging. This study introduces a new laser-based technique that combines in situ Rb-Sr dating and trace-element analysis to evaluate the depositional and alteration histories of Proterozoic shales. The results demonstrate the potential of this method in efficiently dating and distinguishing primary marine processes from secondary ones, making it a powerful tool for future studies of ancient marine shales.
Article
Geochemistry & Geophysics
Dunfeng Xiang, Zhiyong Zhang, Thomas Zack, David Chew, Yueheng Yang, Lin Wu, Johan Hogmalm
Summary: Apatite is a common accessory mineral in different types of rocks, but accurate U-Pb LA-ICP-MS dating is often affected by high levels of common Pb. A new Pb-204 correction method was used in this study to improve accuracy and precision by overcoming isobaric interference issues. Experimental results demonstrate that different reaction gases do not significantly affect the accuracy and precision of U-Pb dating.
GEOSTANDARDS AND GEOANALYTICAL RESEARCH
(2021)
Article
Geosciences, Multidisciplinary
Mikael Tillberg, Henrik Drake, Thomas Zack, Johan Hogmalm, Ellen Kooijman, Mats Astrom
Summary: By using LA-ICP-MS/MS in situ Rb-Sr dating, this study reveals multiple age clusters between ca. 1757 +/- 15 and 355 +/- 12 Ma in mineralization assemblages at three Palaeoproterozoic crystalline bedrock sites, linking fluid flow and fracture reactivation events with far-field orogens and foreland basin evolution. This new approach connects micro-scale age determinations with regional-scale crustal dynamic responses, providing insights into the tectonic evolution of Precambrian cratons.
Article
Geochemistry & Geophysics
Delia Rosel, Thomas Zack
Summary: Due to advancements in reaction cell technologies, LA-ICP-MS/MS can now be used to collect extensive Rb-87/Sr-86 and Sr-87/Sr-86 data sets, allowing for the measurement, calculation, and validation of Rb-Sr ages from individual laser spots. This offers potential for provenance studies and the creation of age maps with unprecedented spatial resolution.
GEOSTANDARDS AND GEOANALYTICAL RESEARCH
(2022)
Article
Geology
Regiane Andrade Fumes, George Luiz Luvizotto, Renato Moraes, Pierre Lanari, Claudio de Morisson Valeriano, Thomas Zack, Mark J. Caddick, Luiz Sergio Amarante Simoes
Summary: By using a combination of in situ techniques, the study assesses the P-T-t path of high-pressure granulites from the Southern Brasilia Orogen. The results provide insights into the crystallization conditions and metamorphic history, indicating peak pressure occurred around 635 Ma with later retrograde conditions and cooling stages.
JOURNAL OF METAMORPHIC GEOLOGY
(2022)
Article
Geosciences, Multidisciplinary
Caio A. Santos, George L. Luvizotto, Renato Moraes, Regiane A. Fumes, Thomas Zack
Summary: The high-pressure metamafic rocks from the Passos Nappe in the Southern Brasilia Orogen were traditionally interpreted as highly retrogressed eclogites, but this study suggests a different metamorphic history. The rocks were likely subducted to depths of at least around 60 km and tectonically emplaced before 579 Ma, based on thermodynamic modeling and geochronology data.
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2021)
Article
Geology
Stefan S. Andersson, Fredrik Sahlstrom, Erik Jonsson, Stefan Luth, Edward P. Lynch, Karin Hogdahl, Thomas Zack, Nils Gies, Stefan Sadbom, K. S. Alexander Hansson, Mikael Bergqvist
Summary: This study investigates the ore mineralogy, textures, and sulphide trace element chemistry of the Palaeoproterozoic Lovisa stratiform Zn-Pb deposit and underlying Lovisa Fe Formation in the Bergslagen ore province in Sweden. It examines the timing of ore formation and modifications in relation to the Svecokarelian orogeny, revealing the complex history of multiple ore types and deformation phases affecting the ores. The findings indicate localized remobilisation of primary sulphides in the Zn-Pb deposit and limited redistribution of trace elements, while the Fe Formation shows signs of significant localised metal redistribution.
ORE GEOLOGY REVIEWS
(2022)
Article
Multidisciplinary Sciences
Andre Baldermann, Santanu Banerjee, Gyorgy Czuppon, Martin Dietzel, Juraj Farkas, Stefan Lohr, Ulrike Moser, Esther Scheiblhofer, Nicky M. Wright, Thomas Zack
Summary: Retrograde clay mineral reactions, particularly glauconite formation, play a significant role in element sequestration in marine sediments. The study reveals that glauconite formation in shallow marine environments leads to substantial element sequestration, with sequestration rates two orders of magnitude higher than deep-sea settings. It is estimated that global uptake of K, Mg, Al, Fe, and Si through glauconite formation in shallow-water environments is half of the estimated Mesozoic elemental flux.
NATURE COMMUNICATIONS
(2022)
Article
Geochemistry & Geophysics
Esther Scheiblhofer, Ulrike Moser, Stefan Loehr, Markus Wilmsen, Juraj Farkas, Daniela Gallhofer, Alice Matsdotter Backstrom, Thomas Zack, Andre Baldermann
Summary: The scarcity of well-preserved and directly dateable sedimentary sequences poses a challenge to inferring the Earth's paleo-environmental evolution. By improving the methods for measuring and interpreting the formation ages of glauconite, a mineral with potential for providing absolute stratigraphic ages for sedimentary sequences, researchers have successfully obtained stratigraphically significant ages for glauconite from a Cretaceous shelfal sequence in northern Germany. The study confirms that glauconite, even in mineralogically complex grains, can preserve pristine ages under burial diagenetic conditions, making it a valuable archive for paleo-environmental reconstructions and direct sediment dating.
Article
Geochemistry & Geophysics
Ahmad Redaa, Juraj Farkas, Sarah Gilbert, Alan S. Collins, Stefan Lohr, Davood Vasegh, Marnie Forster, Morgan Blades, Thomas Zack, Andrea Giuliani, Roland Maas, Andre Baldermann, Martin Dietzel, Dieter Garbe-Schoenberg
Summary: Reference materials with well-characterised composition are essential for reliable isotopic analyses of geological samples. However, there is a general lack of suitable reference materials for in situ Rb-Sr dating of silicate minerals. This study analyzed and tested four pressed nano-powder pellets as RMs, and concluded that only two of them (Mica-Mg-NP and GL-O-NP) were suitable for in situ dating applications, providing accurate Rb-Sr ages for phlogopite, glauconite, and biotite.
GEOSTANDARDS AND GEOANALYTICAL RESEARCH
(2023)
Article
Mineralogy
Dan Holtstam, Fernando Camara, Andreas Karlsson, Henrik Skogby, Thomas Zack
Summary: Ferri-taramite, a complex mineral, was found in the Jakobsberg manganese mine in Sweden. It forms poikiloblastic crystals and has unique physical and chemical properties, which are the result of its formation under high-temperature and high-pressure conditions.
EUROPEAN JOURNAL OF MINERALOGY
(2022)
Article
Chemistry, Analytical
Ahmad Redaa, Juraj Farkas, Sarah Gilbert, Alan S. Collins, Ben Wade, Stefan Lohr, Thomas Zack, Dieter Garbe-Schoenberg
Summary: The study found that the accuracy of in situ Rb-Sr dating of igneous phlogopite mineral using LA-ICP-MS/MS technology is typically within about 3%, with occasional higher errors ranging between 4% to 8%. The bias and uncertainty in the Rb-Sr ages may be related to matrix effects between Mica-Mg and MDC, as well as different physical properties. Developing improved nano-powder reference materials with better matrix matching is crucial for enhancing the accuracy of in situ Rb-Sr dating.
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
(2021)
Article
Geochemistry & Geophysics
Zhen-Min Ge, Xiao-Long Huang, Wei Xie, Tobias W. Hofig, Fan Yang, Yang Yu, S. Khogenkumar Singh
Summary: The mantle source composition of the nascent oceanic crust in the central part of the Gulf of California has been investigated using basaltic glass samples. These samples show trace element patterns similar to enriched mid-ocean ridge basalts, suggesting that the nascent oceanic crust in the Guaymas Basin might be generated through partial melting of a depleted mantle source metasomatized by subducted slab materials.
Article
Geochemistry & Geophysics
Jean-Michel Brazier, Katja E. Goetschl, Martin Dietzel, Vasileios Mavromatis
Summary: This study estimated the distribution coefficient of Zn2+ between calcite/aragonite and reactive fluids and found that the growth rate strongly influences D-Zn(2+) in both minerals. Additionally, a linear correlation was found between D-Zn(2+) and the saturation degree of the reactive fluid.
Article
Geochemistry & Geophysics
Ming Lei, Michele Lustrino, Jifeng Xu, Zhiqiang Kang, Zhengfu Guo, Jianlin Chen
Summary: This study presents a comprehensive geochronological, mineralogical, and geochemical analysis of olivine leucitites in the Maiga area of southern Tibet, suggesting that these rocks originate from a carbonated peridotite mantle source and highlighting the possibility of carbonates being recycled deep into the mantle during continental subduction.
Article
Geochemistry & Geophysics
Yuntao Ye, Xiaomei Wang, Huajian Wang, Haifeng Fan, Zhigang Chen, Qingjun Guo, Ziteng Wang, Chaodong Wu, Donald E. Canfield, Shuichang Zhang
Summary: Phosphorus is an essential element for life and its cycle in the ocean is closely connected with the carbon and oxygen cycles. The study of phosphate oxygen isotopes can provide insights into various reactions related to phosphorus. By analyzing carbonate fluorapatite samples from the Mesoproterozoic Era in North China, it was found that the oxygen isotope values were lower compared to modern samples, indicating a warmer climate during that time period and a potential reason for the scarcity of phosphorite.
Article
Geochemistry & Geophysics
Vincent Busigny, Oanez Lebeau, Didier Jezeduel, Carine Chaduteau, Sean Crowe, Magali Ader
Summary: This study conducted high-precision Mo isotope research on hydrothermal metal sulfides from a porphyry copper deposit in Southwest China and found that different stages of mineralization have distinct Mo isotope compositions, providing valuable insights into the behavior of Mo isotopes in magmatic-hydrothermal systems.
Article
Geochemistry & Geophysics
Min Ji, Xiao-Ying Gao, Yong-Fei Zheng, Bing Gong
Summary: The study examines the anatectic mechanisms in the Himalayan orogen, finding that pressure and temperature control the reaction, while water content mainly affects the solid-phase composition. Dehydration and hydration melting likely occur at different depths in the crust. This research provides important insights into the melting processes in collisional orogens.