Article
Geosciences, Multidisciplinary
John Parnell, Connor Brolly, Adrian J. Boyce
Summary: Graphite deposits can form through metamorphism and fluid processes, with differing origins and structural characteristics in Scotland and other regions. Organic matter may survive metamorphism without fully transforming into ordered graphite, but can yield valuable ordered graphite when mobilized in fluid.
Article
Geosciences, Multidisciplinary
Adrian M. Hall, Hannah Mathers, Maarten Krabbendam
Summary: The study identified a process called glacial ripping in gneiss terrain in lowland Sweden and in hard Cambrian quartz-arenites at Loch Eriboll in NW Scotland. It found that glacial ripping can effectively operate in bedded, hard sedimentary rocks and its impact is significant in till formation. Potential markers for glacial ripping were also identified in other sedimentary terrains in formerly glaciated areas of the Northern Hemisphere.
Article
Geology
Silvia Volante, Annika Dziggel, Jesse B. Walters, Noreen J. Evans, Maximilian Herbst, Richard Albert Roper
Summary: Despite extensive investigation, the tectono-thermal evolution of the Archean crust in the Lewisian Gneiss Complex in NW Scotland (LGC) is still debated. New research suggests that the late Laxfordian deformation and metamorphism were more widespread and occurred at higher temperatures and pressures than previously believed in the southern and northern regions. These findings have important implications for understanding the paleogeographic configuration of NW Scotland during the early Proterozoic.
JOURNAL OF METAMORPHIC GEOLOGY
(2023)
Article
Geochemistry & Geophysics
Robert Chapman, Taija Torvela, Lucia Savastano
Summary: The compositional features of 1887 gold alluvial particles from six localities in central Scotland were analyzed to determine different source mineralizations. The gold particles from each locality were grouped based on alloy and inclusion signatures. Group 1 gold showed a narrow range of simple sulphide and sulphoarsenide inclusion species, while Group 2 gold had a wide range of minerals including molybdenite, bornite, and various Bi and Te-bearing species. The application of compositional templates from other localities indicated that Group 1 gold is orogenic and Group 2 gold is a mixture of porphyry and epithermal origin.
Article
Geosciences, Multidisciplinary
Jeffery M. Valenza, Vamsi Ganti, Alexander C. Whittaker, Michael P. Lamb
Summary: According to the research, a shift in fluvial stratigraphic architecture occurred 1.2 billion years ago, coinciding with the appearance of terrestrial vegetation in the fossil record, which suggests that pre-vegetation rivers typically had shallow, braided planforms. However, recent discoveries of deep, single-thread channels in pre-Silurian strata challenge this view, and it remains unclear how these rivers maintained stable banks. Through the reconstruction of paleohydraulics and channel planform from fluvial cross-strata of the 1.2 Ga Stoer Group, it was found that these deposits exhibit characteristics similar to modern single-thread rivers, suggesting that sediment cohesion from mud alone could have fostered deep, single-thread, pre-vegetation rivers. The Silurian stratigraphic shift may indicate a change in channel migration rate rather than a diversification of planform.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Nadine W. Gabriel, Dominic Papineau, Zhenbing She, Arne Leider, Marilyn L. Fogel
Summary: This study aims to investigate the mineralogy and organic geochemistry of well-preserved late Palaeoproterozoic stromatolitic dolomite from the McLeary Formation, and suggests that chemically oscillating reactions may influence the formation of diagenetic spheroids.
PRECAMBRIAN RESEARCH
(2021)
Article
Geosciences, Multidisciplinary
T. Hammouda, G. Manthilake, P. Goncalves, J. Chantel, J. Guignard, W. Crichton, F. Gaillard
Summary: The study reveals that during the subduction of carbonates, the release and transfer of CO2 initiates compression melting at the lithosphere-asthenosphere boundary, leading to the migration of carbonatite melt away from the mantle wedge. A steady supply of carbonated material by subduction may build up a global carbonatite melt layer at the top of the oceanic asthenosphere.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Biodiversity Conservation
Jinquan Li, Junmin Pei, Jiajia Liu, Jihua Wu, Bo Li, Changming Fang, Ming Nie
Summary: The study found that fires significantly decreased soil carbon and nitrogen content but increased the content and proportion of pyrogenic carbon. The effects of fires vary across different climates and ecosystems, with wildfires and high-severity fires leading to greater losses of soil carbon and nitrogen. Soil carbon and nitrogen levels recovered to control levels approximately 10 years after the fire event.
GLOBAL CHANGE BIOLOGY
(2021)
Review
Polymer Science
Dennis A. Hansell, Monica Orellana
Summary: Marine dissolved organic matter (DOM) holds approximately 660 billion metric tons of carbon, serving as a major carbon reservoir exchangeable with the atmosphere. While the global dynamics of this pool have been better understood in recent decades, the molecular-level control and the role of microgels in this system remain poorly known. This manuscript provides a global context for further insights into this large pool of marine DOM.
Article
Geography, Physical
Jennifer Taylor, David Selby, Jeremy M. Lloyd, Luca Podrecca, Andrew L. Masterson, Bradley B. Sageman, Sonke Szidat
Summary: A sediment core from the salt marsh fringing Loch Duart, NW Scotland, UK, was analyzed using a multi-element geochemical approach to investigate the relative sea level and palaeoenvironmental changes associated with the deglaciation of the British and Irish Ice Sheet. The study utilized various analytical techniques such as rhenium, osmium, carbon, and nitrogen measurements, X-ray fluorescence scanning, radiocarbon dating, and foraminiferal analysis to provide valuable insights into the interplay between post-glacial eustatic rise and glacio-isostatic adjustment.
JOURNAL OF QUATERNARY SCIENCE
(2023)
Article
Geochemistry & Geophysics
Valentin R. Troll, Graeme R. Nicoll, Robert M. Ellam, C. Henry Emeleus, Tobias Mattsson
Summary: The Loch Ba ring-dyke and Centre 3 granites exhibit intense interaction between rhyolitic and basaltic magma. Isotope data suggests significant crustal contribution to the rhyolites, while mafic inclusions show closer proximity to mantle values. Centre 3 magmas show little interaction with deep Lewisian gneiss basement, indicating ascension through previously depleted channels.
CONTRIBUTIONS TO MINERALOGY AND PETROLOGY
(2021)
Article
Multidisciplinary Sciences
Geeth Manthilake, Mainak Mookherjee, Nobuyoshi Miyajima
Summary: The study reveals that C-H-O fluid released from carbonate and chrysotile bearing assemblages in subduction slabs exhibits important electrical conductivity properties, serving as an indicator for carbon migration in subduction zones. Additionally, the oxidized C-H-O fluids are found to play a crucial role in the recycling of carbon in the deep mantle and the stabilization of dolomite in the devolatilization process of chrysotile.
SCIENTIFIC REPORTS
(2021)
Article
Environmental Sciences
Renjie Guo, Tiexi Chen, Xin Chen, Wenping Yuan, Shuci Liu, Bin He, Lin Li, Shengzhen Wang, Ting Hu, Qingyun Yan, Xueqiong Wei, Jie Dai
Summary: In this study, a machine learning model (random forest) was used to establish a global GPP data set named ECGC_GPP. The model distinguished nine functional plant types and estimated monthly GPP data from 1999 to 2019. The results showed a significant contribution of LAI to the monthly variation of GPP, and an upward trend in annual GPP during the study period. The use of plant functional type classification improved the estimation accuracy of cropland GPP.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2023)
Article
Environmental Sciences
Tim Devries, Kana Yamamoto, Rik Wanninkhof, Nicolas Gruber, Judith Hauck, Jens Daniel Mueller, Laurent Bopp, Dustin Carroll, Brendan Carter, Thi-Tuyet-Trang Chau, Scott C. Doney, Marion Gehlen, Lucas Gloege, Luke Gregor, Stephanie Henson, Ji Hyun Kim, Yosuke Iida, Tatiana Ilyina, Peter Landschuetzer, Corinne Le Quere, David Munro, Cara Nissen, Lavinia Patara, Fiz F. Perez, Laure Resplandy, Keith B. Rodgers, Joerg Schwinger, Roland Seferian, Valentina Sicardi, Jens Terhaar, Joaquin Trinanes, Hiroyuki Tsujino, Andrew Watson, Sayaka Yasunaka, Jiye Zeng
Summary: This contribution analyzes the processes that determine the global ocean carbon sink and its trends and variability over the period 1985-2018 using models and observation-based products. The study finds that anthropogenic CO2 dominates the ocean CO2 sink, while climate-driven variability is potentially large but highly uncertain.
GLOBAL BIOGEOCHEMICAL CYCLES
(2023)
Review
Geochemistry & Geophysics
Constantin W. Arnscheidt, Daniel H. Rothman
Summary: The ancient idea of the balance of nature continues to influence modern perspectives on global environmental change. This study reviews the dynamics of the marine carbon cycle and its interactions with climate and life over geologic time, highlighting the importance of feedbacks, critical rates of change, and the application of these ideas to the modern carbon cycle. Understanding the marine record of global environmental disruption is valuable for comprehending the long-term consequences of human-induced changes.
ANNUAL REVIEW OF MARINE SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Graham A. Shields, Robin A. Strachan, Susannah M. Porter, Galen P. Halverson, Francis A. Macdonald, Kenneth A. Plumb, Carlos J. de Alvarenga, Dhiraj M. Banerjee, Andrey Bekker, Wouter Bleeker, Alexander Brasier, Partha P. Chakraborty, Alan S. Collins, Kent Condie, Kaushik Das, David A. D. Evans, Richard Ernst, Anthony E. Fallick, Hartwig Frimmel, Reinhardt Fuck, Paul F. Hoffman, Balz S. Kamber, Anton B. Kuznetsov, Ross N. Mitchell, Daniel G. Poire, Simon W. Poulton, Robert Riding, Mukund Sharma, Craig Storey, Eva Stueeken, Rosalie Tostevin, Elizabeth Turner, Shuhai Xiao, Shuanhong Zhang, Ying Zhou, Maoyan Zhu
Summary: This article reviews the processes that led to the current geological timescale and proposes revisions for subdividing time before 720 million years ago. The assessment of Precambrian rock records suggests that using rock-based concepts for subdivision may require only modest deviation from current chronometric boundaries.
JOURNAL OF THE GEOLOGICAL SOCIETY
(2022)
Article
Geosciences, Multidisciplinary
A. R. Prave, K. Kirsimae, A. Lepland, A. E. Fallick, T. Kreitsmann, Yu E. Deines, A. E. Romashkin, D. Rychanchik, P. Medvedev, M. Moussavou, K. Bakakas, M. S. W. Hodgskiss
Summary: The study suggests that the C-13 isotope trend of the LJE is facies-dependent rather than representative of the global carbon cycle. While open and deeper marine environments maintained stable carbon isotope values, nearshore and evaporitic environments showed higher C-13 values. Changes in C-13 values are linked to facies changes and may be related to local carbon pools.
JOURNAL OF THE GEOLOGICAL SOCIETY
(2022)
Article
Engineering, Environmental
Cynthia Faye Isley, Kara L. Fry, Xiaochi Liu, Gabriel Michael Filippelli, Jane A. Entwistle, Adam P. Martin, Melanie Kah, Diana Meza-Figueroa, John T. Shukle, Khadija Jabeen, Abimbola O. Famuyiwa, Liqin Wu, Neda Sharifi-Soltani, Israel N. Y. Doyi, Ariadne Argyraki, Kin Fai Ho, Chenyin Dong, Peggy Gunkel-Grillon, C. Marjorie Aelion, Mark Patrick Taylor
Summary: This study evaluated the concentrations of trace metals in indoor dust from homes in 35 countries and identified the main sources of these metals along with associated household characteristics. The findings suggest that factors such as home age, peeling paint, and garden access are important considerations for managing potential risks posed by indoor house dust, with chromium concentrations in indoor dust having the greatest health risk impact.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Geology
Joyce E. Neilson, Rosalia Barili, Alexander Brasier, Luiz F. De Ros, Sarah Ledingham
Summary: The Late Cambrian Steptoean Positive Carbon Isotope Excursion marks a significant change in ocean chemistry and trilobite faunas, indicating that marine cements during this period may have been composed of aragonite. The study found that as the carbon isotope excursion reached its peak, the marine cements showed increasing concentrations of strontium before dropping off post-peak, consistent with aragonitic cements.
DEPOSITIONAL RECORD
(2022)
Article
Geochemistry & Geophysics
Karyne M. Rogers, Adam P. Martin, Giovanni Pradel, Yuwei Yuan, Yongzhi Zhang, Rose E. Turnbull
Summary: A regional soil study in the Marlborough region of New Zealand characterized the geochemical baselines of different land-use types using stable isotopes and elements. The study focused on vineyard soils and found higher levels of certain elements and isotopes compared to forested and rural soils. The research also identified distinct natural geogenic inputs and compared the findings with urban and rural soils in other parts of New Zealand.
APPLIED GEOCHEMISTRY
(2022)
Article
Soil Science
G. Shrestha, R. Calvelo-Pereira, P. Roudier, A. P. Martin, R. E. Turnbull, G. Kereszturi, P. Jeyakumar, C. W. N. Anderson
Summary: This study evaluates several combinations of sensors for accurate quantification of soil trace elements. Model fusion methods provide optimal prediction results.
Article
Statistics & Probability
Tilman M. Davies, Sudipto Banerjee, Adam P. Martin, Rose E. Turnbull
Summary: This study investigates the relationships between local environmental variables and the geochemical composition of the Earth in a specific region of New Zealand. By constructing a hierarchical spatial factor model, handling missing data, and using sparse approximations to Gaussian processes for inference, this study provides novel insights into geochemical processes. The results, presented graphically through web-based applications, confirm existing knowledge and offer a basis for future research hypotheses in geochemistry.
JOURNAL OF THE ROYAL STATISTICAL SOCIETY SERIES C-APPLIED STATISTICS
(2022)
Article
Marine & Freshwater Biology
Nicola Allison, Phoebe Ross, Alex Brasier, Nadia Cieminska, Nicolas Lopez Martin, Catherine Cole, Chris Hintz, Ken Hintz, Adrian Finch
Summary: Ocean acidification alters the morphology of coral skeletons, including the shrinking of polyp size and changes in skeletal structure.
Article
Multidisciplinary Sciences
R. T. Kramer, R. L. Kinaston, P. W. Holder, K. F. Armstrong, C. L. King, W. D. K. Sipple, A. P. Martin, G. Pradel, R. E. Turnbull, K. M. Rogers, M. Reid, D. Barr, K. G. Wijenayake, H. R. Buckley, C. H. Stirling, C. P. Bataille
Summary: This article introduces the use of strontium isotope analysis to trace the origin of locally produced agricultural products in New Zealand, and establishes a regional bioavailable strontium isoscape. By testing the source of cow milk, the article demonstrates the potential of this model.
Article
Geochemistry & Geophysics
Madeleine E. Murphy, Paul S. Savage, Nicholas J. Gardiner, Anthony R. Prave, Richard M. Gaschnig, Roberta L. Rudnick
Summary: By analyzing the silicon isotope composition of glacial diamictites from different geological ages, researchers have established the long-term secular record of the compositional evolution of upper continental crust. The study shows that the variability of silicon isotopes in diamictites decreases over time, indicating the diminishing importance of glacially milled banded iron formation and tonalite-trondhjemite-granodiorites in post-Archaean continental crust. The research also suggests that the upper continental crust becomes increasingly homogeneous through atmospheric oxygenation and crustal reworking.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Biology
Eva E. Stueken, Anthony R. Prave
Summary: Nitrogen isotopes and abundances in sedimentary rocks are a valuable tool for understanding ancient ecosystems. There are two different nitrogen archives in the rock record, and their isotopic ratios can be offset from each other. This offset increases with metamorphic grade, suggesting a relationship with the bonding environment and isotope fractionation. However, the theoretical bounds for this effect are not yet established. In this study, an unexpectedly large isotopic offset was observed in low-grade metamorphic siltstones from the Mesoproterozoic Diabaig Formation. These rocks also contain evidence of fossilized microbial mats, suggesting that diagenetic ammonium release from these mats may explain the isotopic offset. This study highlights the importance of nitrogen isotopes in understanding past environments and nutrient cycling.
Article
Geology
Claire E. Keevil, Mike Rogerson, Daniel R. Parsons, Ramon Mercedes-Martin, Alexander T. Brasier, John J. G. Reijmer, Anna Matthews
Summary: Understanding the flow of carbon in hyperalkaline lakes is crucial for understanding their biogeochemistry, sedimentology, and paleoenvironmental and paleoclimatic records. A geophysical survey of Mono Lake, California, reveals unexpected geomorphological control on the formation of lacustrine carbonate formations. The study also finds a strong link between the location of carbonate columns and meteoric Ca supply to the lake, suggesting that water management could enhance carbon capture in these lakes.
JOURNAL OF SEDIMENTARY RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Christopher J. Spencer, Neil S. Davies, Thomas M. Gernon, Xi Wang, William J. McMahon, Taylor Rae Morrell, Thea Hincks, Peir K. Pufahl, Alexander Brasier, Marina Seraine, Gui-Mei Lu
Summary: The evolution of land plants during the Palaeozoic era had a significant impact on the biosphere and sedimentary rocks. By analyzing the isotopic signatures of zircon formed at subduction zones, researchers found a correlation between the composition of continental crust and the evolution of vascular plants. They also discovered that the expansion of terrestrial vegetation resulted in changes in weathering and sedimentary systems, ultimately altering the composition of continental crust.
Article
Astronomy & Astrophysics
Eva E. Stueken, Kalle Kirsimae, Aivo Lepland, Anthony R. Prave
Summary: Hydrothermal vents are important in the search for life on other planets due to their ability to generate catalytic surfaces and organic compounds. This study investigates the role of hydrothermal circulation in maintaining a biosphere beyond its origin by analyzing organic carbon, nitrogen abundances, and isotopic ratios from ancient rocks in Russia. The results suggest that hydrothermal activity in ancient marine basins could provide a high flux of recycled nitrogen, supporting a large biosphere on anoxic worlds.
Article
Geosciences, Multidisciplinary
A. R. Prave, A. E. Fallick, K. Kirsimae
Summary: The Tonian-Cambrian Dalradian Supergroup in Scotland is a thick siliciclastic-carbonate succession. The conventional view is that it formed in rift basins, with the Grampian Group infilling deep marine turbidites and the Appin Group marking basin-bounding palaeohighs. However, new isotopic and geochemical data suggest that the previous correlations are unreliable and there is no evidence for palaeohighs or rift basins. Instead, the Grampian-Appin groups formed in response to the midTonian Knoydartian Orogeny.
JOURNAL OF THE GEOLOGICAL SOCIETY
(2023)