Article
Environmental Sciences
Wokil Bam, Kanchan Maiti, Mark Baskaran
Summary: The distribution and vertical fluxes of particulate organic carbon and other key elements in the Arctic Ocean are mainly influenced by primary productivity, ice cover, and lateral exchange. Seasonal vertical fluxes of particulate organic and inorganic carbon, nitrogen, and biogenic silica were studied using tracers in the western Arctic Basin in 2015. The results highlight the importance of POC and PN fluxes in seasonal vertical transport, with the highest fluxes observed in ice-covered stations in the northern region.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Multidisciplinary Sciences
Nils Schorndorf, Norbert Frank, Simon M. Ritter, Sophie F. Warken, Christian Scholz, Frank Keppler, Denis Scholz, Michael Weber, Jeronimo Aviles Olguin, Wolfgang Stinnesbeck
Summary: Underwater secondary carbonates called Hells Bells have been discovered in sinkholes in the Yucatan peninsula, Mexico. Through dating and geochemical analysis, it is found that the formation of Hells Bells is closely linked to sea-level rise and changing hydrological conditions in the aquifer.
SCIENTIFIC REPORTS
(2023)
Article
Computer Science, Interdisciplinary Applications
Ruby C. Marsden, Christopher L. Kirkland, Martin Danisik, Matthew L. Daggitt, Ung-San Ahn, Bjarne Friedrichs, Noreen J. Evans
Summary: A new analytical and data reduction workflow for zircon U-Th disequilibrium analysis using SHRIMP II was developed in this study, with a case study on trachytic samples from Jeju Island demonstrating the effectiveness of the new approach.
COMPUTERS & GEOSCIENCES
(2022)
Article
Environmental Sciences
Huina Hu, Xiao Liu, Chunyan Ren, Renming Jia, Yusheng Qiu, Minfang Zheng, Min Chen
Summary: The analysis of Po-210 and Pb-210 activity concentrations near Prydz Bay revealed variations in dissolved and particulate activity concentrations in different oceanic regions, reflecting the dynamics of organic matter particles.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Geosciences, Multidisciplinary
Xiaoyu Jiao, Zhiwen Dong, Giovanni Baccolo, Xuejiao Chen, Xiang Qin, Yaping Shao
Summary: In this study, the U isotopic method was used to analyze cryoconite samples from various glaciers in western China. The spatial variability of the (U-234/U-238) activity ratio and residence time, as well as the transport mechanism of the dust cycle in the region, were explored. The results showed that the average (U-234/U-238) activity ratios were higher in southern TP glaciers and lower in northeastern TP locations, indicating a decreasing trend from south to north. In the Tianshan region, the (U-234/U-238) activity ratio was higher in central areas compared to eastern areas, indicating a decreasing trend from west to east.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2023)
Article
Environmental Sciences
Qiangqiang Zhong, Tao Yu, Hui Lin, Jing Lin, Jianda Ji, Jialin Ni, Jinzhou Du, Dekun Huang
Summary: Estimating POC fluxes using Po-210-Pb-210 disequilibria in seawater samples from the western North Pacific Ocean, researchers found different distributions of Po-210 and Pb-210 in the euphotic zone and deep ocean regions.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Oceanography
Natalie C. Harms, Niko Lahajnar, Birgit Gaye, Tim Rixen, Ulrich Schwarz-Schampera, Kay-Christian Emeis
Summary: This study focuses on particulate matter fluxes in the oligotrophic Indian Ocean subtropical gyre (IOSG), revealing extremely low fluxes of particulate matter and particulate organic carbon due to strong stratification and nutrient depletion in the area. The lack of seasonality in POC fluxes is attributed to intense organic matter degradation, variations in the ocean mixed layer depth (OMLD), and the impacts of physical mixing in the gyre. The findings highlight the importance of investigating POC export fluxes in the deep ocean to predict future changes in the global carbon cycle under climate warming conditions.
DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY
(2021)
Article
Oceanography
Jiaying Li, Zhifei Liu, Baozhi Lin, Yulong Zhao, Junyuan Cao, Xiaodong Zhang, Jingwen Zhang, Chen Ling, Pengfei Ma, Jiawang Wu
Summary: Zooplankton fecal pellets play an important role in the export of particulate organic carbon (POC) in the ocean. However, their characteristics and contribution to POC flux have not been well studied in the tropical marginal sea. In this study, the fecal pellet flux in the South China Sea was investigated for the first time. The results showed significant temporal and spatial variations in fecal pellet flux, with higher fluxes during the winter monsoon. The presence of extra-large pellets in the deep sea indicated in-situ repackaging of deep-dwelling zooplankton communities. Fecal pellets contributed significantly to the total POC flux, especially during the winter monsoon.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Geochemistry & Geophysics
Daniil Popov, Richard A. Spikings
Summary: The study indicates that the host minerals may hinder diffusive Pb loss from apatite inclusions by limiting the Pb flux across their boundaries. Additionally, when apatite boundaries are flux-limited, heterogeneities in U and Th concentration within apatite may cause U-Th-Pb dates to increase towards the boundaries.
Article
Geochemistry & Geophysics
Sota Niki, Shuhei Kosugi, Hideki Iwano, Tohru Danhara, Takafumi Hirata
Summary: In this study, a new technique combining CRC-ICP-MS system and msLA protocol was used for in situ U-Th disequilibrium dating of zircon and monazite samples, resulting in ages consistent with previous chronological constraints.
GEOSTANDARDS AND GEOANALYTICAL RESEARCH
(2022)
Article
Oceanography
Nwabisa Malongweni, Emma Rocke, Michael J. Roberts, Sarah L. C. Giering
Summary: Vertical particle fluxes of particulate organic carbon (POC), chlorophyll a (Chl a), and biogenic silica (bSi) were measured in the productive shelf of southern Africa. The study found a turbid layer called the benthic nepheloid layer (BNL) near the seabed, which affects the breeding success of squid. The inshore area had higher POC fluxes compared to offshore, and the fluxes of Chl a and bSi were higher in the inshore area as well. Bottom fluxes were significantly higher inshore, indicating the contribution of sinking organic particles and resuspended bottom sediments. The POC export efficiency and transfer efficiency were also high in the study area.
DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY
(2023)
Proceedings Paper
Nuclear Science & Technology
Dan Filipescu, Hongwei Wang, Gongtao Fan, Katsuhisa Nishio, Tsutomu Ohtsuki, Ioana Gheorghe, Konstantin Stopani, Anabella Tudora, Fumi Suzaki, Kentaro Hirose, Makoto Inagaki, Marianne Bjoroen, Yiu-Wing Lui, Takashi Ari-Izumi, Shuji Miyamoto, Hiroaki Utsunomiya
Summary: The International Atomic Energy Agency (IAEA) conducted a research project to measure photonuclear cross-section data for unexplored nuclei and cases of discrepant existing data. The study involved a series of experiments at the NewSUBARU synchrotron radiation facility of SPring8 in Japan, investigating photoneutron reactions for 11 nuclei from Be-9 to Bi-209. The measurements were carried out using a developed neutron detection array and sorting techniques.
15TH INTERNATIONAL CONFERENCE ON NUCLEAR DATA FOR SCIENCE AND TECHNOLOGY, ND2022
(2023)
Article
Geosciences, Multidisciplinary
Szabolcs Kosik, Takeshi Hasegawa, Martin Danisik, Karoly Nemeth, Makoto Okada, Bjarne Friedrichs, Axel K. Schmitt
Summary: Accurate and precise dating of young eruptions is crucial for volcanic forecasting and assessing volcanic hazards. However, dating Quaternary eruptions can be challenging due to limited applicable methods. In this study, the authors conducted independent age determinations and a paleomagnetic analysis on the volcanic succession of the Puketerata maar-lava dome complex in New Zealand. The results indicate that the most recent eruptions occurred around 11.5 thousand years ago, which is younger than previously estimated, providing valuable information for volcanic hazards assessment.
EARTH PLANETS AND SPACE
(2023)
Proceedings Paper
Nuclear Science & Technology
A. Chatillon, G. Boutoux, T. Gorbinet, L. Grente, J. -F. Martin, E. Pellereau, J. Taieb, H. Alvarez-Pol, L. Audouin, Y. Ayyad, G. Belier, J. Benlliure, M. Caamano, E. Casarejos, D. Cortina-Gil, A. Ebran, F. Farget, B. Fernandez-Dominguez, A. Heinz, H. T. Johansson, B. Jurado, A. Kelic-Heil, N. Kurz, B. Laurent, B. Loeher, C. Nociforo, C. Paradela, S. Pietri, A. Prochazka, D. Ramos, J. L. Rodriguez-Sanchez, C. Rodriguez, D. Rossi, H. Simon, L. Tassan-Got, H. Toernqvist, J. Vargas, B. Voss, H. Weick
Summary: Low energy fission of (234,235,236,238)u and Np-237,Np-381 radioactive beams was investigated using the (RB)-B-3/SOFIA setup at the GSI/FRS facility. The setup allows for simultaneous identification of the fissioning nucleus and fission fragments on an event-by-event basis, as well as prompt-neutron emission detection. This study presents new results on elemental, isobaric, and isotopic yields.
15TH INTERNATIONAL CONFERENCE ON NUCLEAR DATA FOR SCIENCE AND TECHNOLOGY, ND2022
(2023)
Article
Geochemistry & Geophysics
Sota Niki, Shuhei Kosugi, Hideki Iwano, Tohru Danhara, Takafumi Hirata
Summary: In this study, in situ U-238-Th-230 dating was conducted using an ICP-mass spectrometer coupled with a laser ablation sampling system. The combination of a collision/reaction cell system and a multiple-spot laser ablation system improved the accuracy and signal-to-background ratio for analytes. The developed technique was successfully applied to volcanic zircon and monazite samples from Japan, with results consistent with previous chronological constraints.
GEOSTANDARDS AND GEOANALYTICAL RESEARCH
(2022)
Article
Oceanography
Jason A. Law, Robert H. Weisberg, Yonggang Liu, Dennis A. Mayer, Jeffrey C. Donovan
Summary: Time series data from a moored array of sensors are used to describe the long-term mean circulation and seasonal variations on the West Florida Continental Shelf. The observations reveal a coherent shelf-wide circulation pattern with alongshore and down-coast flow, and a coastal jet separating an upwelling region from a downwelling region influenced by the deeper ocean.
DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY
(2024)
