Article
Engineering, Civil
Ruo-Mei Wang, Chen-Feng You, Chuan-Hsiung Chung, Kuo-Fang Huang, Ya-Ju Hsu
Summary: The study finds that the (U-234/U-238) in small mountainous rivers (SMRs) in Taiwan can reflect the relative contributions of physical erosion and chemical weathering within the river catchment. The mountain area is mainly characterized by physical erosion, which increases (U-234/U-238) and reduces U concentrations, inhibiting chemical weathering. In contrast, the decreased (U-234/U-238) and increased Na/Li and δLi-7 downstream indicate enhanced chemical weathering.
JOURNAL OF HYDROLOGY
(2022)
Article
Geosciences, Multidisciplinary
Xinyu Liu, Xianwei Zhang, Lingwei Kong, Gang Wang, Honghu Liu
Summary: Chemical weathering reduces the strength and stability of granite regolith and increases its water sensitivity. Understanding the correlation between chemical weathering and mechanical properties of regolith is crucial for assessing gully erosion. This study investigates the chemical weathering of granite and evaluates the appropriateness of previous chemical weathering indices, providing a comprehensive dataset on the properties of granite regolith and enhancing the understanding of chemical weathering.
Article
Geosciences, Multidisciplinary
Xinyu Liu, Xianwei Zhang, Lingwei Kong, Gang Wang, Honghu Liu
Summary: Chemical weathering significantly affects the strength and stability of granite regolith, and studying the correlation between chemical weathering degree and mechanical properties can enhance understanding of geomorphological evolution.
Article
Geosciences, Multidisciplinary
Patrick J. Frings, Marcus Oelze, Franziska Schubring, Daniel A. Frick, Friedhelm von Blanckenburg
Summary: Metal and metalloid stable isotope ratios are important proxies for weathering, element cycling, and export in the Critical Zone. By studying sites with varying erosion rates and regolith residence times, it was found that three key parameters influence these isotope ratios, particularly in the case of silicon. The research also highlights how the composition of clay minerals plays a significant role in expressing fractionation factors related to silicon isotope ratios.
AMERICAN JOURNAL OF SCIENCE
(2021)
Article
Geochemistry & Geophysics
P. O'Brien, S. Byrne
Summary: A novel three-dimensional landscape model was developed to study the space weathering processes of lunar regolith, revealing that materials typically spend only a few million years on the lunar surface due to vigorous mixing by small-scale impacts. By comparing modeled surface residence times with measurements of space weathering maturity, the rate of space weathering and the timescale for regolith to reach maturity on the lunar mare were estimated.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2021)
Article
Environmental Sciences
Jinke Liu, Guilin Han, Di Wang
Summary: In this study, the researchers investigated the co-weathering of silicate, carbonate, and sulfide minerals in the upper Changjiang River and its impact on the long-term carbon cycle. The results show that the CO2 release from sulfide oxidation coupled with carbonate dissolution exceeds the CO2 drawdown from silicate weathering in the Changjiang River basin.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2023)
Article
Geosciences, Multidisciplinary
Ting Gao, Meng Qi, Zhengrong Wang, Runsheng Yin, Chengshuai Liu, Yuhui Liu, Shan Ke, Zhi-Qi Zhao
Summary: The climate has a significant impact on Mg isotope fractionation during continental weathering, and the patterns of Mg mobilization and fractionation during granite weathering differ in distinct climate zones.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2023)
Article
Geography, Physical
Huayong Wu, Xiaodong Song, Feng Liu, Decheng Li, Gan-Lin Zhang
Summary: This study focuses on the effect of topography on the structure of the critical zone in a low hilly region. Seismic refraction and borehole surveys were conducted to examine the thickness of the regolith and the underlying bedrock. The results show that topography controls the distribution of different layers and the overall structure of the critical zone.
EARTH SURFACE PROCESSES AND LANDFORMS
(2022)
Article
Geosciences, Multidisciplinary
Haowei Mei, Xing Jian, Wei Zhang, Hanjing Fu, Shuo Zhang
Summary: Continental weathering is essential in connecting Earth's spheres, shaping landscapes, and regulating chemical cycles and global climate. A study in southeast China on granitic regolith profiles reveals intensive chemical weathering in top-soil samples, with depletion of plagioclase and K-feldspar and formation of kaolinite. The underlying oxidized-soil samples show higher chemical index of alteration values and enrichment of certain elements, indicating the importance of petrographic and mineralogical proxies in evaluating weathering intensity for regolith profiles.
Article
Geochemistry & Geophysics
Alissa White, Lin Ma, Bryan Moravec, Jon Chorover, Jennifer McIntosh
Summary: Tracing water routing and groundwater contribution to streamflow using U-series activity ratios and radiogenic Sr isotope ratios provides a better understanding of limited water resources. The study focused on a montane catchment in the Valles Caldera National Preserve, northern NM, where U-Th fractionation and weathering profiles indicate differences between sites with volcanic breccia and fractured tuff underlying hillslopes. Isotope mixing analysis suggests that deep groundwater from fractured tuff aquifer systems dominates streamflow in the catchment.
Article
Geochemistry & Geophysics
Yu-Han Qi, Ying-Zeng Gong, Fei Wu, Ying Lu, Wenhan Cheng, Fang Huang, Hui-Min Yu
Summary: The study of V behavior during chemical weathering provides valuable insights into V isotope compositions of weathered upper continental crust and river water, helping to understand the transfer of V from the land to the ocean.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Geology
Y. S. Suiekpayev, Y. M. Sapargaliyev, A. Dolgopolova, F. Pirajno, R. Seltmann, S. Khromykh, G. K. Bekenova, P. D. Kotler, M. M. Kravchenko, A. Zh Azelkhanov
Summary: The formation of the Karaotkel Ti-Zr placers is influenced by long-term regional geological processes, coastal wave formation, and subsequent sedimentation. The deposit contains abundant light rare-earth elements, with micro-inclusions of gold and monazite found in geochemical and microprobe analyses. The U-Pb dating technique determined a crystallization age of 287 ± 1 Ma for the deposit.
ORE GEOLOGY REVIEWS
(2021)
Article
Geosciences, Multidisciplinary
Julien Bouchez, Friedhelm von Blanckenburg
Summary: The stable isotope ratio of strontium at Earth's surface is mainly affected by biological uptake and storage in plant litter. Strontium removal in plant litter is more significant than recycling, while dissolved strontium export is highest at sites with faster erosion rates.
AMERICAN JOURNAL OF SCIENCE
(2021)
Review
Environmental Sciences
M. D. Covington, J. B. Martin, L. E. Toran, J. L. Macalady, N. Sekhon, P. L. Sullivan, A. A. Garcia, J. B. Heffernan, W. D. Graham
Summary: Earth's Critical Zone (CZ), influenced by underlying bedrock, is extensively studied for silicate-dominated landscapes but less so for carbonate landscapes. However, carbonate rocks cover around 15% of Earth's surface and provide essential resources. This study reviews the state of knowledge of the carbonate CZ, explores contrasts in different carbonate settings, and calls for integrative studies to develop a conceptual framework for the role of carbonates in the CZ.
Article
Geochemistry & Geophysics
Jon K. Golla, Julien Bouchez, Marie L. Kuessner, Daniella M. Rempe, Jennifer L. Druhan
Summary: This study investigates the long-term relationships between stream chemistry and discharge, and how they are regulated by watershed subsurface structure and biogeochemical functioning. The findings reveal that during intense storm events, stream lithium isotope signatures can record the routing of water and generation of solutes within the hillslope, providing insights into the variability of stream chemistry. These results have significant implications for understanding stream ecosystems and hydrogeochemical processes.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geochemistry & Geophysics
Lingyu Zhang, Kristoffer Szilas
Summary: This study presents new petrological and geochemical data for the Narssaq Ultramafic Body (NUB) in the Itsaq Gneiss Complex of SW Greenland. The results indicate that the ultramafic rocks of NUB are not mantle residues, but instead represent crustal cumulates derived from high-Mg magmas.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Rong Xu, Sarah Lambart, Oliver Nebel, Ming Li, Zhongjie Bai, Junbo Zhang, Ganglan Zhang, Jianfeng Gao, Hong Zhong, Yongsheng Liu
Summary: This study investigated the iron isotope compositions of Cenozoic basalts in Southeast China, finding significant variations related to different types of basalts and their respective sources.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
C. J. Ebinger, Miriam C. Reiss, Ian Bastow, Mary M. Karanja
Summary: The East African rift system is formed above mantle upwellings and the formation of rifts is related to lithospheric thinning and magmatic activity. The amount of splitting varies spatially and the fast axes are predominantly parallel to the orientation of the rifts. Thick lithospheric modules have less splitting and different orientations, which may indicate mantle plume flow. Splitting rotates and increases in strength as it enters the rift zones, suggesting that the anisotropy is mainly present at shallow depths.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Correction
Geochemistry & Geophysics
Ekaterina Rojas-Kolomiets, Owen Jensen, Michael Bizimis, Gene Yogodzinski, Lukas Ackerman
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Robert W. Nicklas, Igor S. Puchtel, Ethan F. Baxter
Summary: Oxygen fugacity is a fundamental parameter for understanding redox processes in igneous systems. This study compares the Fe-XANES oxybarometry method with the V-in-olivine method for evaluating fO(2) in MORB lavas. The results show that the V-in-olivine method is not applicable to samples with low MgO content, and that the majority of Archean komatiite sources have lower fO(2) than modern MORB.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Chunfei Chen, Stephen F. Foley, Sebastian Tappe, Huange Ren, Lanping Feng, Yongsheng Liu
Summary: The volatile components CO2 and H2O play a major role in mantle melting and heterogeneity. In this study, Ca isotopes were used to trace the lithological heterogeneity in alkaline magmatic rocks. The results revealed the presence of K-richterite and carbonate components as the source of alkaline magmas with low delta 44/40Ca values. These findings highlight the importance of Ca isotopes as a robust tracer of lithological variation caused by volatiles in the Earth's upper mantle.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Timothee Jautzy, Gilles Rixhon, Regis Braucher, Romain Delunel, Pierre G. Valla, Laurent Schmitt, Aster Team
Summary: Although the current approach to estimate catchment-wide denudation rates using only 10Be concentrations has made significant progress in geomorphology, this study argues for the inclusion of 26Al measurements and testing of steady-state assumptions in slow eroding, formerly glaciated landscapes. The study conducted measurements of both 10Be and 26Al in stream sediments from the Vosges Massif in France and found that elevation, slope, channel steepness, and precipitation were the primary factors controlling denudation rates. The study also revealed a significant relationship between the extent of past glaciation and the cosmogenic (un-)steadiness in the stream sediments.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Erik van der Wiel, Douwe J. J. van Hinsbergen, Cedric Thieulot, Wim Spakman
Summary: Numerical models of Earth's mantle dynamics can predict the vigour and mixing of mantle flow, and the average slab sinking rates are an unexplored parameter that can provide intrinsic information on these characteristics. Through numerical experiments, it has been found that slab sinking rates are strongly correlated with mantle convection and mixing, and may explain geochemical observations from hotspot volcanoes.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)