Article
Geochemistry & Geophysics
Tomoaki Nishikawa, Takuya Nishimura, Yutaro Okada
Summary: The study detected earthquake swarms along the Hikurangi Trench in New Zealand using the ETAS model, finding that most earthquake swarm sequences were intraplate events concentrated along the east coast of the North Island. Some earthquake swarms occurred several days before slow slip events, suggesting that SSE-induced stress loading may not be the triggering mechanism for these pre-SSE earthquake swarms.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geochemistry & Geophysics
Keisuke Yoshida, Masaoki Uno, Toru Matsuzawa, Yohei Yukutake, Yusuke Mukuhira, Hiroshi Sato, Takeyoshi Yoshida
Summary: This study investigates an ongoing intense earthquake swarm in the northeastern Noto Peninsula, Japan, which commenced at the end of 2019. Despite the absence of volcanic activity in the region for the past 15 million years, the research suggests that the seismicity is associated with fluids released by ancient or unrecognized modern magmatic activity. The seismic activity has resulted in significant crustal deformation and has activated a complex network of faults at depths shallower than 20 km.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
Y. Yukutake, K. Yoshida, R. Honda
Summary: Recent seismic and geodetic observations indicate the involvement of pressurized fluid and aseismic slip during earthquake swarms. However, the interaction between these two factors is not fully understood. In this study, the researchers observed geodetic signals induced by aseismic opening and shear dislocation, as well as hypocenter migration during an earthquake swarm in the Hakone volcano, central Japan. The observations suggest that fluid intrusion caused the aseismic slip, and the complex migration of the hypocenters reflects the propagation of aseismic slip.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geosciences, Multidisciplinary
Keisuke Yoshida, Naoki Uchida, Yoshiaki Matsumoto, Masaki Orimo, Tomomi Okada, Satoshi Hirahara, Shuutoku Kimura, Ryota Hino
Summary: A M-w 6.2 earthquake occurred in Suzu, northeastern Noto Peninsula, Japan, on May 5, 2023, following a 2.5-year intense earthquake swarm. The mainshock rupture was initiated near the shallow end of the preceding swarm earthquakes, with systematic upward migration likely caused by fluid movement. The results emphasize the importance of monitoring swarm events, as they can lead to large and dangerous earthquakes.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Water Resources
Yuheng Yang, Baisha Weng, Denghua Yan, Xiaoyan Gong, Yanyu Dai, Yongzhen Niu, Guoqiang Dong
Summary: The study focused on analyzing the contribution of different water sources to streamflow in the Nagqu River watershed on the Qinghai-Tibet Plateau. The results showed that rain and snowmelt reflected the chemical characteristics of precipitation, with groundwater and snowmelt being the primary sources of water flow. Different types of groundwater were identified in the region, with varying levels of permeability and recoverability.
JOURNAL OF HYDROLOGY-REGIONAL STUDIES
(2021)
Article
Engineering, Environmental
Atiyeh Mojiri-Khozani, Hamid Reza Nassery, Yaser Nikpeyman, Hossein Abedian
Summary: This study assesses the impact of the Koohrang III tunnel in Iran on the contiguous springs that provide water for drinking and agricultural activities. Prior to tunnel sealing, water seepage into the tunnel was estimated at 11.6 MCM/year, with the highest seepage occurring in karstic formations. After sealing, the total water seeping into the tunnel decreased to about 5.1 MCM/year. The tunnel excavation has caused a decrease in the flow of some springs.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2023)
Article
Chemistry, Multidisciplinary
Marino Domenico Barberio, Francesca Gori, Maurizio Barbieri, Tiziano Boschetti, Antonio Caracausi, Giovanni Luca Cardello, Marco Petitta
Summary: The study in the San Vittorino Plain in central Italy found that high-angle faults play a crucial role in the influx of deep fluids into regional carbonate aquifers. Through hydrogeochemical and geological research, the study identified how and where aquifers are intersected by faults, providing guidance for monitoring variations in groundwater geochemistry.
APPLIED SCIENCES-BASEL
(2021)
Article
Geochemistry & Geophysics
R. L. Tyne, H. Barry, A. Cheng, D. J. Hillegonds, J-H Kim, J. C. McIntosh, C. J. Ballentine
Summary: This study analyzes the helium isotope and abundance data from the Paradox Basin in the Colorado Plateau, USA, to reveal the distribution and migration of noble gases in groundwater and hydrocarbon samples. The research finds that the Paradox Formation acts as an effective barrier to helium diffusion, with a strong regional influence. This is crucial for exploring and storing sub-salt helium and hydrogen, and also plays a critical role in determining groundwater ages.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Y. Amezawa, Y. Hiramatsu, A. Miyakawa, K. Imanishi, M. Otsubo
Summary: The factors controlling the duration of earthquake swarms, especially long-living ones, remain unclear. A severe earthquake swarm occurred on the Noto peninsula in Japan, lasting for more than 4 years and including ten M > 4.0 earthquakes. The swarm consisted of four seismic clusters, with diffusive hypocenter migrations observed in three clusters and rapid diffusive migration associated with intermittent seismicity in the southern cluster. The nature of the fluid supply, intermittent seismicity, and low-permeability environment are identified as the key causes of this long-living earthquake swarm.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Jonathan Schenk, Henrique O. Sawakuchi, Anna K. Sieczko, Gustav Pajala, David Rudberg, Emelie Hagberg, Kjell Fors, Hjalmar Laudon, Jan Karlsson, David Bastviken
Summary: Methane plays a crucial role in the carbon cycling of lakes, with methane oxidation serving as a powerful tool to determine whether methane is oxidized or emitted in lakes. In boreal lakes, the δC-13 of methane sources in littoral sediments is consistently higher than that in deep waters, potentially due to variability in organic matter substrates. Additionally, lateral hydrological transport of methane from catchment areas may be an important factor in lake methane cycling.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Environmental Sciences
Abdulhalim Zaryab, Hamid Reza Nassery, Kay Knoeller, Farshad Alijani, Eddy Minet
Summary: This study investigates the geochemistry and stable isotope composition of the Kabul urban aquifer, the main source of drinking water for Kabul city's inhabitants. The findings suggest that nitrate pollution in the aquifer primarily originates from sewage rather than artificial fertilizer. The results highlight the importance of improving sewage collection systems in the Kabul Plain.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Geosciences, Multidisciplinary
E. Thebault, G. Hulot, B. Langlais, P. Vigneron
Summary: The detailed mapping of Earth's magnetic field, using satellite and near-surface measurements, has produced a global model with SH degree 1050 that is in agreement with previous satellite-based models at large wavelengths. The model is stable when downward continued to the Earth's surface and fits the CHAMP and Swarm satellite data down to expected noise levels.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
P. Dublanchet, L. De Barros
Summary: Earthquake swarms are commonly interpreted as being caused by fluid diffusion from a deep source, destabilizing critically stressed faults. However, these swarms expand faster than fluid diffusion is likely to occur. Recent observations in the Corinth rift in Greece also reveal that swarms consist of bursts of rapidly migrating events, which cannot be explained by the diffusion model. To account for these features, it is necessary to consider slow slip on faults in addition to fluid diffusion.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geochemistry & Geophysics
Michael A. Antonelli, Andrea Giuliani, Zaicong Wang, Meiling Wang, Lian Zhou, Lanping Feng, Ming Li, Zhaofeng Zhang, Fang Liu, Russell N. Drysdale
Summary: The study investigates the Ca isotope compositions of kimberlites and their relation to mantle-derived magmas and the deep Earth carbon cycle. The results show that kimberlites have similar Ca isotope compositions as carbonatites and OIB, and slightly lower than MORB. The findings suggest that kimberlites do not require subducted carbonates in their mantle sources, despite their high CO2 contents. The study also suggests that the pressure effects on Ca isotope fractionation may not be significant for kimberlite melts.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Geosciences, Multidisciplinary
Benjamin Birner, Jeffrey Severinghaus, Bill Paplawsky, Ralph F. Keeling
Summary: Using a high-precision mass spectrometry technique, researchers have found that the concentration of helium in the atmosphere has significantly increased over the past five decades due to fossil fuel emissions. This finding also implies an increase in the concentration of helium-3, exceeding estimates of anthropogenic emissions.