Results 71 to 80 of about 835 (219)

Evolution Model for the Paleoproterozoic Talvivaara Mudstone‐Hosted Ni‐Zn‐Cu‐Co Deposit in Fennoscandia

Terra Nova, EarlyView.
ABSTRACT The Paleoproterozoic Talvivaara mudstone is a very large sulfidic Ni‐Co deposit that records enhanced organic matter accumulation during the global Shunga Event. Here, rock geochemistry and microscale S and Fe isotope composition of in situ pyrrhotites and pyrites are studied in well‐characterised, well‐preserved drill core samples.
Raimo Lahtinen, Jaakko J. Laitala, Joonas J. Virtasalo, Martin J. Whitehouse   +3 more
wiley   +1 more source

Extraordinary methane levels in a small bar‐built tropical estuary

Limnology and Oceanography Letters, Volume 11, Issue 4, July 2026.
Abstract Small estuaries link uplands and nearshore marine environments but are understudied in many regions. We quantified spatial and temporal variability in CH4, CO2, nutrients, and organic matter in a small, deep, bar‐built tropical estuary in Fajardo, Puerto Rico.
William H. McDowell, Tatiana Barreto‐Vélez, Ricardo Colón‐Rivera, Jody D. Potter   +3 more
wiley   +1 more source

Hyperspectral Fingerprinting of Dune Sediments Across the Arabian Peninsula: Insights Into Sediment Provenance and Transport Pathways From NASA's EMIT Data

Geophysical Research Letters, Volume 53, Issue 12, 28 June 2026.
Abstract The Arabian Peninsula encompasses one of the world's most extensive aeolian systems, yet the provenance and transport history of its dune sediments are not well understood. Using hyperspectral data from NASA's Earth Surface Mineral Dust Source Investigation (EMIT), we mapped mineral compositions and abundance patterns across dune fields and ...
Ahmed Alshakr, Mohamed Sultan, Mustafa Kemal Emil, Hassan Alharbi, Fahad Alshehri, Abdullah A. Alotaibi, Abdullah T. Mohammad, Aylin Yildirim, Neil C. Sturchio   +8 more
wiley   +1 more source

Low Abundances of Ultramafic Components in the Chang'e‐6 Landing Site Basalt and Ejecta Material

Geophysical Research Letters, Volume 53, Issue 12, 28 June 2026.
Abstract The South Pole‐Aitken (SPA) Basin, the Moon's largest impact structure, holds key insights into lunar evolution, prompting the Chang'e‐6 mission to return first samples for ground‐truth verification. Analysis of over 6,000 grains from the Chang'e‐6 soil returned from the SPA Basin reveals a composition dominated by clinopyroxene (26.5–32.9 vol.
Zhenbing She, Zaicong Wang, Tianyang Li, Hao Zhang, Qi He, Yiheng Li, Antong Gao, Yi Gu, Zichen Wei, Yan Zhuang, Changhao Ni, Shuang Shi, Jiawei Li, Jiawei Zhao, Wen Zhang, Jiaqi Zheng, Xu Chen, Keqing Zong, Zhaochu Hu, Xiang Wu, Long Xiao   +20 more
wiley   +1 more source

Elucidating the Reactivity and Fate of Dissolved Organic Matter in Groundwater Entering the Alaska Beaufort Sea Coast Using 14C Ramped Oxidation

Geophysical Research Letters, Volume 53, Issue 11, 16 June 2026.
Abstract Supra‐permafrost groundwater (SPGW) is a significant but understudied source of dissolved organic matter (DOM) to Arctic coastal systems. We applied ramped pyrolysis/oxidation (RPO) with Δ14C and δ13C isotopic analysis to assess DOM reactivity and origin in SPGW, river, and lagoon waters along the Alaska Beaufort Sea coast.
C. T. Connolly, R. G. M. Spencer, J. W. McClelland   +2 more
wiley   +1 more source

Anomaly-Guided Double Autoencoders for Hyperspectral Unmixing

Remote Sensing
Deep learning has emerged as a prevalent approach for hyperspectral unmixing. However, most existing unmixing methods employ a single network, resulting in moderate estimation errors and less meaningful endmembers and abundances.
Hongyi Liu, Chenyang Zhang, Jianing Huang, Zhihui Wei   +3 more
doaj   +1 more source

Sodium Tetraazidoaurate(III)—From Na[AuCl4]·2H2O to Na[Au(N3)4] and Beyond One Step at a Time

Chemistry – A European Journal, Volume 32, Issue 22, 9 June 2026.
Novel sodium chlorido‐/azidoaurate(III) dihydrates Na[AuCl4–x(N3)x]·2H2O (x = 0, 1, 2, 3, 4) provide the first example of a complete series of gradual substitution on tetramer complex anions to be described. Controlled dehydration of Na[Au(N3)4]·2H2O leads to Na[Au(N3)4]·H2O and Na[Au(N3)4], the latter being a highly explosive material.
Mehmet Somer, Joannis Psilitelis, Raul Cardoso‐Gil, Thomas Doert, Franziska Jach, Ayberk Yılmaz, Alexander Ovchinnikov, Yurii Prots, Helge Rosner, Marcus P. Schmidt, Peter Höhn   +10 more
wiley   +1 more source

An Isotope‐Based Snapshot Reveals the Combined Influence of High‐Elevation Recharge and Local Return Flows on Groundwater Across Guatemala City

Hydrological Processes, Volume 40, Issue 6, June 2026.
Representation (not to scale) of potential high elevation recharge and low elevation return flows within the Guatemala City metropolitan area. ABSTRACT Guatemala City is the most populous urban center in Central America. In this urban center, groundwater extraction within the last 40 years has substantially declined water table levels and accelerated ...
Ricardo Sánchez‐Murillo, Angela Méndez, Héctor Espinoza, Juan Camacho‐Puerto   +3 more
wiley   +1 more source

Vertical and Spatial Geochemical Variations of Nishinoshima Volcaniclastic Deposits, Japan, During Episode 4

New Zealand Journal of Geology and Geophysics, Volume 69, Issue 2, June 2026.
Nishinoshima is a volcanic island in the Ogasawara Arc that has exhibited intermittent activity since 2013, including four major eruptive episodes: 2013–2015 (Episode 1), 2017 (Episode 2), 2018 (Episode 3), and 2019–2020 (Episode 4). Previous studies reported a change in eruption style—from a Strombolian eruption with lava flows (Episode 1 to the early
Erika Tanaka, Kenta Yoshida, Tomoki Sato, Yoshiro Nishio, Yoshihiko Tamura   +4 more
wiley   +1 more source

Bioanalytical TERS and Advanced Data Processing Methods

Journal of Raman Spectroscopy, Volume 57, Issue 6, Page 977-994, June 2026.
Tip‐enhanced Raman spectroscopy delivers label‐free, subnanometer vibrational imaging of biological systems. Recent advances in instrumentation, data analysis, and ambient/liquid operation enable surface‐selective mapping of molecular heterogeneity in proteins, nucleic acids, membranes, and viruses, positioning TERS as a powerful platform for nanoscale
Sarika Joshi, Ankit Dodla, Sarthak Saxena, Twinkle Soni, Sumit Saxena, Shobha Shukla, Bayden R. Wood   +6 more
wiley   +1 more source