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Three-dimensional glacial isostatic adjustment modeling reconciles conflicting geographic trends in North American marine isotope stage 5a relative sea level observations Geology (IF 5.8) Pub Date : 2023-09-01 Schmitty B. Thompson, Jessica R. Creveling, Konstantin Latychev, Jerry X. Mitrovica
Glacial isostatic adjustment (GIA) simulations using earth models that vary viscoelastic structure with depth alone cannot simultaneously fit geographic trends in the elevation of marine isotope stage (MIS) 5a relative sea level (RSL) indicators across continental North America and the Caribbean and yield conflicting estimates of global mean sea level (GMSL). We present simulations with a GIA model
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A Mars-analog sulfate mineral, mirabilite, preserves biosignatures Geology (IF 5.8) Pub Date : 2023-09-01 Karena K. Gill, Elliot A. Jagniecki, Kathleen C. Benison, Martha E. Gibson
Various sulfate minerals exist on Mars; except for gypsum, they are understudied on Earth. Extremophiles have been documented in modern gypsum and halite and ancient halite, but other chemical sediments have not been evaluated for biosignatures. Here, we present the first observations and analysis of microorganisms and organic compounds in primary fluid inclusions in the Mars-analog mineral mirabilite
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Faunal provinciality in the Late Cretaceous Western Interior Seaway using network modeling Geology (IF 5.8) Pub Date : 2023-09-01 Ceara Purcell, Louis Scuderi, Corinne Myers
The Western Interior Seaway (WIS) was historically divided into latitudinal faunal provinces that were taxonomically distinct from the adjacent Gulf Coastal Plain (GCP) and that shifted in space due to sea-level changes. However, no rigorous quantitative analyses using recent taxonomic updates have reassessed these provinces and their associations. We used network modeling of macroinvertebrate WIS
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Li isotope ratios of spring fluids as an effective tracer of slab-derived subducted sources across the Costa Rica forearc Geology (IF 5.8) Pub Date : 2023-09-01 Jacob P. Helper, Jaime D. Barnes, J. Maarten de Moor, Alejandro Rodríguez, Peter H. Barry, Evan J. Ramos, John C. Lassiter
Spring waters from across the Costa Rica margin were analyzed for their Li and He isotope compositions to determine the utility of Li isotopes as a tracer of volatile sources in subduction zones. Li isotope ratios systematically decrease with increasing depth to the subducting slab: averaging +15.0‰ ± 9.2‰ in the outer forearc (<40 km to the slab), +9.3‰ ± 4.3‰ in the forearc (40–80 km to the slab)
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Timing of carbon uptake by oceanic crust determined by rock reactivity Geology (IF 5.8) Pub Date : 2023-09-01 Elmar Albers, Svenja Jöns, Axel Gerdes, Andreas Klügel, Christoph Beier, Simone A. Kasemann, Wolfgang Bach
Carbonate formation during the alteration of oceanic crust is a global CO2 sink. Its timing and controls are not well understood, particularly in volcanic seamounts, which react with seawater over tens of millions of years. We report in situ U-Pb age dates of carbonate vein and void fill in 50–74 Ma basaltic basement of the Louisville Seamount Chain. More than 90% of the carbonate formed <20 m.y. after
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Field calibration of 40Ar/39Ar K-feldspar multiple diffusion domain (MDD) thermal histories at the Grayback normal fault block, Arizona, USA Geology (IF 5.8) Pub Date : 2023-09-01 Martin S. Wong, Phillip B. Gans, Damian Roesler
Numerous studies suggest that 40Ar/39Ar K-feldspar analyses record continuous thermal histories from ~300 °C to 150 °C due to the presence of multiple diffusion domains (MDDs). Such continuous thermal histories can provide significant advantages over thermochronometers that only record cooling through a single closure temperature. However, some studies have questioned the reliability of 40Ar/39Ar K-feldspar
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Limited sulfur degassing and muted environmental impact of Ontong Java Plateau lavas Geology (IF 5.8) Pub Date : 2023-09-01 James Eguchi, Shuo Ding, Benjamin A. Black
The mainly deep-submarine Ontong Java Plateau (OJP) is the result of the largest outpouring of lava in the geologic record. Volcanic events of this magnitude can have dramatic environmental impacts due to volatile emissions. We report new S measurements in naturally glassy, olivine-hosted melt inclusions and pillow basalt glasses from the OJP. We combined these data with previous S measurements in
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Challenger Deep basalts reveal Indian-type Early Cretaceous oceanic crust subducting in the southernmost Mariana Trench Geology (IF 5.8) Pub Date : 2023-09-01 Wenjing Xu, Xiaotong Peng, Robert J. Stern, Xisheng Xu, Hengchao Xu
Why the Challenger Deep, the deepest point on Earth’s solid surface, is so deep is unclear, but part of the reason must be the age and density of the downgoing plate. Northwest Pacific oceanic crust subducting in the Izu-Bonin-Mariana Trench is Cretaceous and Jurassic, but the age and nature of Pacific oceanic crust subducting in the southernmost Mariana Trench remains unknown. Here we present the
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Silicification of trilobites and biofilm from the Cambrian Weeks Formation, Utah: Evidence for microbial mediation of silicification: REPLY Geology (IF 5.8) Pub Date : 2023-09-01 Leslie A. Melim, Sebastien R. Mure-Ravaud, Thomas A. Hegna, Brian J. Bellott, Rudy Lerosey-Aubril
Abstract not available
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Magma migration and surface uplift in Pamir–western Tibet driven by deep lithospheric dynamics Geology (IF 5.8) Pub Date : 2023-09-01 Gong-Jian Tang, Derek A. Wyman, Wei Dan, Qiang Wang, Mustafo Gadoev, Ilhomjon Oimahmadov
There are two parallel >1200-km-long semi-continuous (ultra)potassic magmatic belts in the southern (Karakorum-Lhasa) and the northern (Central Pamir–western Kunlun) parts of Pamir–western Tibet. The southern belt is widely attributed to northward subduction of the Indian plate, while it has been suggested that the northern belt relates to the southward subduction of the Asian plate. We report new
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Asymmetric glaciation, divide migration, and postglacial fluvial response times in the Qilian Shan Geology (IF 5.8) Pub Date : 2023-09-01 Jingtao Lai, Kimberly Huppert
Glacial-interglacial cycles have repeatedly perturbed climate and topography in many midlatitude mountain ranges during the Quaternary. Glacial erosion can move drainage divides and induce fluvial adjustments downstream, yet the time scale over which these adjustments occur remains unclear. We examined landscape evolution in the northwest-southeast–trending Qilian Shan, where the contrast in solar
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Electrical image of magmatic system beneath the Xiangshan volcanogenic uranium deposit, southeast China: Linking magmatic evolution and uranium metallogenesis Geology (IF 5.8) Pub Date : 2023-09-01 Hui Yu, Juzhi Deng, Bin Tang, Gary Egbert, Hui Chen
The uranium deposit of the Early Cretaceous Xiangshan caldera (southeast China) represents the world’s third-largest volcanogenic uranium deposit. While the hydrothermal system defines uranium mineralization in shallow volcanic-intrusive complexes, we argue that the underlying magmatic system, identified in magnetotelluric data from the Xiangshan deposit, is equally crucial in controlling the origin
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In situ carbon storage potential in a buried volcano Geology (IF 5.8) Pub Date : 2023-09-01 Ricardo Pereira, Davide Gamboa
In situ mineral carbonation in porous and permeable mafic and ultramafic volcanic rocks is proposed to be a promising process that can contribute toward safe and permanent CO2 sequestration. Here, we investigated a partially buried Late Cretaceous composite volcano located offshore the central West Iberian margin as a proxy for potential in situ mineral carbonation in volcanic edifices on continental
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The complex Rodrigues triple junction migration since ca. 8 Ma: A response to episodic Amsterdam–St. Paul hotspot tail capture by the Southeast Indian Ridge? Geology (IF 5.8) Pub Date : 2023-09-01 Christine M. Meyzen, Ulrich Schwarz-Schampera
The mutual intersection of three plate boundaries, so-called triple junctions, has long been recognized as crucial boundaries for unraveling the spatiotemporal motion of tectonic plates. Yet, the dynamic and tectonic processes ruling their migration remain enigmatic. At the Rodrigues triple junction, the Southwest Indian Ridge lengthens northeastward in response to the unsteady linearity of the Southeast
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The permeability of loose magma mush Geology (IF 5.8) Pub Date : 2023-09-01 Eloïse Bretagne, Fabian B. Wadsworth, Jérémie Vasseur, Madeleine C.S. Humphreys, Donald B. Dingwell, Katherine J. Dobson, Martin F. Mangler, Shane M. Rooyakkers
Models for the evolution of magma mush zones are of fundamental importance for understanding magma storage, differentiation in the crust, and melt extraction processes that prime eruptions. These models require calculations of the permeability of the evolving crystal frameworks in the mush, which influences the rate of melt movement relative to crystals. Existing approaches for estimating the crystal
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Discovery of Permian–Triassic eclogite in northern Tibet establishes coeval subduction erosion along an ~3000-km-long arc Geology (IF 5.8) Pub Date : 2023-09-01 Chen Wu, Andrew V. Zuza, Drew A. Levy, Jie Li, Lin Ding
Eclogite bodies exposed across Tibet record a history of subduction-collision events that preceded growth of the Tibetan Plateau. Deciphering the time-space patterns of eclogite generation improves our knowledge of the preconditions for Cenozoic orogeny in Tibet and broader eclogite formation and/or exhumation processes. Here we report the discovery of Permo-Triassic eclogite in northern Tibet. U-Pb
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Revealing the link between A-type granites and hottest melts from residual metasedimentary crust Geology (IF 5.8) Pub Date : 2023-09-01 B.B. Carvalho, O. Bartoli, B. Cesare, M. Satish-Kumar, M. Petrelli, T. Kawakami, T. Hokada, M. Gilio
Among S-, I-, and A-type granites, the latter are the most debated in terms of origin, and metasedimentary crust is usually discarded as a potential source. Here we tackle this issue by adopting an in-source perspective, rather than focusing on the final product (granite), documenting the occurrence of pristine melt inclusions (MIs) in garnet from residual metapelitic ultrahigh-temperature (UHT) granulite
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Large-scale rare-metal pegmatite deposit formation driven by supercontinent assembly Geology (IF 5.8) Pub Date : 2023-09-01 Gong-Jian Tang, Derek. A. Wyman, Qiang Wang, Wei Dan, Lin Ma, Ya-Nan Yang
Triassic rare-metal pegmatite deposits are widespread in East Asia; e.g., the western Kunlun and Songpan-Ganze belt in northern Tibet and the Altai belt in the heart of the Central Asian Orogenic Belt. However, rare-metal enrichment processes and deposit formation mechanisms are enigmatic. Most rare-metal pegmatites in East Asia formed at ca. 220–200 Ma in the Late Triassic and are genetically related
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Surface exposure constraints on the mantle water budget Geology (IF 5.8) Pub Date : 2023-09-01 K. Chotalia, J. Brodholt, C. Lithgow-Bertelloni
Mantle water content estimates range from 0.5 to 15 oceans of water. Its evolution is even more unclear. Rapid degassing during mantle solidification likely released much of the water to the surface, initially flooding Earth. However, evidence for subaerial land from at least 3.5 Ga means that much of this water must have been rapidly cycled back into the mantle. Here, we used a parameterized convection
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Silicification of trilobites and biofilm from the Cambrian Weeks Formation, Utah: Evidence for microbial mediation of silicification: COMMENT Geology (IF 5.8) Pub Date : 2023-09-01 Yeongju Oh, Yong-Hoe Choe, John S. Peel, Yong Yi Zhen, Patrick Smith, Tae-Yoon S. Park
Abstract not available
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Stable tungsten isotopic composition of seawater over the past 80 million years Geology (IF 5.8) Pub Date : 2023-08-01 Ruiyu Yang, Daniel Stubbs, Tim Elliott, Tao Li, Tianyu Chen, Adina Paytan, David B. Kemp, Hongfei Ling, Jun Chen, James R. Hein, Christopher D. Coath, Gaojun Li
The isotopic composition of seawater provides valuable information on how the Earth system has evolved. Here we present the stable tungsten isotopic composition (δ186/184W) of seawater recorded in three ferromanganese (Fe-Mn) crusts spanning the past 80 million years in the Pacific. The δ186/184W of Fe-Mn crusts displays a pronounced decrease of ∼0.2‰ from 60 Ma to 40 Ma followed by a stable value
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Along-strike seismotectonic segmentation reflecting megathrust seismogenic behavior Geology (IF 5.8) Pub Date : 2023-08-01 Ehsan Kosari, Matthias Rosenau, Sabrina Metzger, Onno Oncken
Understanding the along-strike seismogenic behavior of megathrusts is crucial to anticipating seismic hazards in subduction zones. However, if and how spatiotemporal frictional heterogeneity (high and low kinematic coupling) at depth feeds back into the upper-plate deformation pattern and how the upper-plate elastic signals and permanent records may correlate have yet to be fully understood. Hence
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Yangtze and Cathaysia blocks of South China: Their separate positions in Gondwana until early Paleozoic juxtaposition Geology (IF 5.8) Pub Date : 2023-08-01 Lijun Wang, Shoufa Lin, Wenjiao Xiao
The position of South China in Gondwana remains controversial. In all previous models, the Yangtze and Cathaysia blocks, the two major components of South China, were amalgamated by the Tonian, and South China was considered to be a single coherent block in Gondwana. Based on a summary and critical reevaluation of available paleomagnetic, paleontological, stratigraphic, and detrital zircon data, we
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Strain shadow “megapores” in mid-crustal ultramylonites Geology (IF 5.8) Pub Date : 2023-08-01 Florian Fusseis, Craig Allsop, James Gilgannon, Christoph Schrank, Simon Harley, Christian M. Schlepütz
Mylonitic shear zones are important fluid conduits in the Earth’s crust. They host transient and permeable porosity that facilitates fluid transfer and controls fluid-rock interaction. Here we present microstructural observations from a mid-crustal ultramylonite with very large pores that occupy the strain shadows of albite porphyroclasts. Our non-invasive three-dimensional X-ray microtomographic data
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Valanginian climate cooling and environmental change driven by Paraná-Etendeka basalt erosion Geology (IF 5.8) Pub Date : 2023-08-01 L.M.E. Percival, E. Ownsworth, S.A. Robinson, D. Selby, S. Goderis, P. Claeys
The Valanginian Weissert Event (ca. 134 Ma) has long been linked to emplacement of the Paraná-Etendeka large igneous province (LIP). Although several Mesozoic crises were triggered by volcanic CO2 emissions and global warming, causing oceanic oxygen depletion, the Weissert Event featured climate cooling and limited marine anoxia. Here, the impact of silicate weathering on environmental change during
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Middle Miocene fire activity and C4 vegetation expansion in the Barstow Formation, California, USA Geology (IF 5.8) Pub Date : 2023-08-01 Katharine M. Loughney, Anna Harkness, Catherine Badgley
C4 grassland ecosystems expanded across North America between ca. 8 and 3 Ma. Studies of ungulate enamel and environmental indicators from the middle Miocene Barstow Formation of southern California (USA) have demonstrated the presence of C4 vegetation prior to the late Miocene expansion of C4 grasslands. Fire promotes the growth of modern C4 grasslands and may have contributed to the Miocene expansion
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Older than they look: Cryptic recycled xenotime on detrital zircon Geology (IF 5.8) Pub Date : 2023-08-01 Maximilian Dröllner, Milo Barham, Christopher L. Kirkland, Malcolm P. Roberts
Dating of xenotime outgrowths (XOs) has been used to obtain depositional age constraints on sedimentary sequences devoid of volcanic tuffs and biostratigraphically useful fossils (i.e., most of Earth history). Here, we present geochronological and geochemical data from XOs on detrital zircon from the Early Cretaceous Broome Sandstone, NW Australia. Ages of XOs predate the palynologically constrained
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Southwest Borneo, an autochthonous Pangea-Eurasia assembly proxy: Insights from detrital zircon record Geology (IF 5.8) Pub Date : 2023-08-01 Long Xiang Quek, Shan Li, Christopher K. Morley, Azman A. Ghani, Junbin Zhu, Muhammad Hatta Roselee, Sayed Murthadha, Rezal Rahmat, Yu-Ming Lai, Lediyantje Lintjewas
The current tectonic model for Borneo in SE Asia suggests that the SW Borneo block rifted from NW Australia at ca. 190 Ma and drifted across the Tethyan Ocean to collide with Eurasia in the Early Cretaceous. But, the global zircon Hf trend after 200 Ma indicates that circum-Pacific-style accretionary orogens prevail. The SW Borneo detrital zircon data set, which combines our new data with previous
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Boninitic melt percolation makes depleted mantle wedges rich in silica Geology (IF 5.8) Pub Date : 2023-08-01 Ming Chen, Jianping Zheng, Hong-Kun Dai, Qing Xiong, Min Sun, Mikhail M. Buslov, Xiang Zhou, Jingao Liu
Global fore- and sub-arc peridotites show paradoxically highly melt-depleted yet silica-enriched (as excess orthopyroxene) compositions, which have been attributed to either silica-enriched mantle sources or metasomatic overprints by silica-rich fluids/melts. Here, we present robust mineralogical evidence from an ophiolitic peridotite suite and thermodynamic modeling suggesting that boninitic melt
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Avulsion dynamics determine fluvial fan morphology in a cellular model Geology (IF 5.8) Pub Date : 2023-08-01 Harrison K. Martin, Douglas A. Edmonds
Fluvial fans are large, low-gradient depositional systems that occur in sedimentary basins worldwide. Fluvial fans can represent much of the geologic record of foreland basins, create hazards, and record paleoclimate and tectonic signals. However, we lack an understanding of how fluvial fans grow into the variety of shapes observed around the world. We explored this aspect using a cellular model of
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Hadean tectonics: Insights from machine learning Geology (IF 5.8) Pub Date : 2023-08-01 Guoxiong Chen, Timothy Kusky, Lei Luo, Quanke Li, Qiuming Cheng
The tectonic affiliations and magma compositions that formed Earth’s earliest crusts remain hotly debated. Previous efforts toward this goal have relied heavily on determining the provenance of Hadean zircons using low-dimensional discriminant diagrams developed from Phanerozoic samples, which are inadequate for capturing systematic differences without considering secular changes in zircon composition
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Slow changes in lava chemistry at Kama‘ehuakanaloa linked to sluggish mantle upwelling on the margin of the Hawaiian plume Geology (IF 5.8) Pub Date : 2023-08-01 Aaron J. Pietruszka, Michael O. Garcia, Richard W. Carlson, Erik H. Hauri
Temporal variations in lava chemistry at active submarine volcanoes are difficult to decipher due to the challenges of dating their eruptions. Here, we use high-precision measurements of 226Ra-230Th disequilibria in basalts from Kama‘ehuakanaloa (formerly Lō‘ihi) to estimate model ages for recent eruptions of this submarine Hawaiian pre-shield volcano. The ages range from ca. 0 to 2300 yr (excluding
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Impact of long-term erosion on crustal stresses and seismicity in stable continental regions Geology (IF 5.8) Pub Date : 2023-08-01 Stephane Mazzotti, Xavier Vergeron, Oswald Malcles, Juliette Grosset, Philippe Vernant
The causes of seismicity in stable continental regions (SCRs) remain an open question, in particular with respect to (1) the transient or steady-state nature of the forcing mechanisms and (2) the bias toward shallow seismicity. In this study, we test the impact of long-term localized erosion on crustal stresses and the promotion or inhibition of seismicity in SCRs. We subject numerical models with
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Crustal architectural controls on critical metal ore systems in South China based on Hf isotopic mapping Geology (IF 5.8) Pub Date : 2023-08-01 Zhi-Yu Zhang, Zeng-Qian Hou, Qing-Tian Lü, Xiao-Wei Zhang, Xiao-Fei Pan, Xian-Ke Fan, Yong-Qian Zhang, Chen-Guang Wang, Yong-Jun Lü
There is increasing demand for critical metals (e.g., W-Sn, Li-Be-Nb-Ta, and rare earth elements [REEs]) to sustain the transition to green energy, yet it is unclear what controls the formation of such critical metal ore systems. Here, we focus on South China, which is well endowed with critical metals, and imaged its crustal architecture by zircon Hf isotopic mapping using 1096 zircon Hf isotope data
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Mafic microgranular enclaves (MMEs) trace the origin of post-collisional magmas Geology (IF 5.8) Pub Date : 2023-08-01 Daniel Gómez-Frutos, Antonio Castro
Mafic microgranular enclaves (MMEs) are a ubiquitous feature of post-collisional magmatism, receiving much attention among earth scientists over the last decades. While recent advances point to the large-scale involvement of the lithospheric mantle in granite petrogenesis, MMEs have received less attention in such discussion. Because MMEs are commonly acknowledged to represent the mafic end member
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Late Quaternary paleoceanography of Vestnesa Ridge, Fram Strait: Ostracode species as a potential indicator of cold seep activity Geology (IF 5.8) Pub Date : 2023-08-01 Rachel Wai Ching Chu, Moriaki Yasuhara, Karoline Myrvang Riise, Hirofumi Asahi, Huai-Hsuan May Huang, Laura J. Cotton, Yuanyuan Hong, Tine L. Rasmussen
Past intensity of methane release from deep-ocean methane hydrates continues to be challenging to reconstruct reliably. Here, we used fossil ostracode fauna paired with foraminiferal δ13C values in a marine sediment core from Vestnesa Ridge, western Svalbard margin, to reconstruct methane seepage activity during the late Quaternary and to examine faunal response to deglacial climatic changes. Benthic
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Cobalt mineralogy at the Iron Creek deposit, Idaho cobalt belt, USA: Implications for domestic critical mineral production Geology (IF 5.8) Pub Date : 2023-08-01 E.A. Holley, N. Zaronikola, J. Trouba, K. Pfaff, J. Thompson, E. Spiller, C. Anderson, R. Eggert
Current U.S. policies aim to establish domestic supply chains of critical minerals for the energy transition. The Iron Creek deposit in the Idaho cobalt belt (ICB) is one of the most promising cobalt (Co) targets. Our case study illustrates the importance of mineralogy in strategic evaluations of critical mineral potential. Most of the Co at Iron Creek occurs as Fe substitution in pyrite, with lattice-bound
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Mud volcanoes guided by thrusting in compressional settings Geology (IF 5.8) Pub Date : 2023-08-01 Juan I. Soto, Michael R. Hudec
Mud volcanoes are fed largely by fracture systems, but fracture systems are common in fold- and-thrust belts (FTBs), and not all of them extrude mud volcanoes. One popular hypothesis is that mud volcanoes extrude up normal faults and fractures in the crests of thrust-related anticlines. Using a high-resolution depth-migrated seismic cube in the northwestern Gulf of Mexico, we demonstrate the occurrence
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Mass wasting records the first stages of the Messinian Salinity Crisis in the eastern Mediterranean Geology (IF 5.8) Pub Date : 2023-07-01 Davide Oppo, Christopher A.-L. Jackson, Christian Gorini, David Iacopini, Sian Evans, Vittorio Maselli
The geological processes that occurred during the deposition of the Mediterranean salt giant are poorly constrained, limiting our understanding of the earliest phase of the Messinian Salinity Crisis (MSC). Using three-dimensional seismic reflection data from the northern Levant Basin in the eastern Mediterranean Sea, we investigated a previously unrecognized deposit at the base of the Messinian halite
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A mechanism for transient creep in crustal shear zones Geology (IF 5.8) Pub Date : 2023-07-01 Christopher A. Thom, James D. Kirkpatrick
The brittle-to-ductile transition in faults and shear zones marks the change from frictional stick-slip behavior in the seismogenic zone to creep accommodated by plastic mechanisms at higher temperatures. Geodetic observations of slow slip events (SSEs) on plate-boundary shear zones indicate that transient periods of elevated aseismic slip rate occur beneath the seismogenic zone where dislocation creep
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Fast exhumation of Earth’s earliest ultrahigh-pressure rocks in the West Gondwana orogen, Mali Geology (IF 5.8) Pub Date : 2023-07-01 Carlos E. Ganade, Daniela Rubatto, Pierre Lanari, Joerg Hermann, Lucas R. Tesser, Renaud Caby
Did exhumation of ultrahigh-pressure (UHP) rocks proceed at comparable rates in the Neoproterozoic and in modern collisional orogens? We address this question with a multimineral geochronological study of UHP rocks from the Gourma fold-and-thrust belt in Mali. Integrated petrology and zircon U-Pb geochronology reveal peak metamorphic conditions of 820–740 °C and 3.3–3.4 GPa at 611.7 ± 3.6 Ma, providing
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Progressive lawsonite eclogitization of the oceanic crust: Implications for deep mass transfer in subduction zones Geology (IF 5.8) Pub Date : 2023-07-01 David Hernández-Uribe, Tatsuki Tsujimori
Lawsonite eclogites are major hosts of H2O and trace elements and thus key for long-term deep element cycling in subduction zones. Existing cycling models suggest that the subducting oceanic crust transforms to lawsonite-eclogite assemblages; yet the scarcity of lawsonite eclogites in the rock record questions to what extent the oceanic crust transforms to lawsonite-eclogite assemblages during subduction
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ERRATUM: New estimates of the magnitude of the sea-level jump during the 8.2 ka event Geology (IF 5.8) Pub Date : 2023-07-01 Jonathan Obrist-Farner, Mark Brenner, Jeffery R. Stone, Marta Wojewódka-Przybył, Thorsten Bauersachs, Andreas Eckert, Marek Locmelis, Jason H. Curtis, Susan R.H. Zimmerman, Alex Correa-Metrio, Lorenz Schwark, Edward Duarte, Antje Schwalb, Etienne Niewerth, Paula Gabriela Echeverría-Galindo, Liseth Pérez
ORIGINAL ARTICLE: 2022, v. 50, no. 1, p. 86–90, https://doi.org/10.1130/G49296.1. First published 30 September 2021.ERRATUM PUBLICATION: 2023, v. 51, no. 7, p. 703–703, https://doi.org/10.1130/G49296E.1. First published 10 May 2023Figure 2 of the original article contained an error in the location of some of the radiocarbon dates in Cores 1 and 2. This does not change the main findings of the paper
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Precise U-Pb dating of incremental calcite slickenfiber growth: Evidence for far-field Eocene fold reactivation in Ireland Geology (IF 5.8) Pub Date : 2023-07-01 V. Monchal, K. Drost, D. Chew
The Variscan orogen in southern Ireland and Britain is characterized by an intensely deformed, E-W–trending fold-and-thrust belt. Farther north in Ireland, the Carboniferous North Dublin Basin exhibits tight chevron folds and kinematically linked en echelon vein sets, along with bedding-parallel veins with slickenfibers. This deformation is assumed to be Variscan in age, despite lying 150 km north
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Mechanical weakening of a mudrock seal by reaction with CO2-charged fluids Geology (IF 5.8) Pub Date : 2023-07-01 Andreas Busch, Suzanne Hangx, Stephanie Vialle, Roberto Emanuele Rizzo, Niko Kampman
The long-term interaction of CO2-charged fluids with low permeability cap rocks is important for seal integrity assessment. To address this potential risk, we studied long-term geomechanical changes in a reservoir seal due to fluid-rock interactions with CO2-charged fluids, focusing on a natural CO2 analogue near Green River, Utah, USA. The observed chemo-mechanical changes are on the millimeter scale
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Ammonoid extinction versus nautiloid survival: Is metabolism responsible? Geology (IF 5.8) Pub Date : 2023-07-01 Amane Tajika, Neil H. Landman, J. Kirk Cochran, Kozue Nishida, Kotaro Shirai, Toyoho Ishimura, Naoko Murakami-Sugihara, Kei Sato
Understanding the mechanism of selective extinction is important in predicting the impact of anthropogenic environmental changes on current ecosystems. The selective extinction of externally shelled cephalopods at the Cretaceous-Paleogene (K-Pg) mass extinction event (ammonoids versus nautiloids) is often studied, but its mechanism is still debated. We investigate the differences in metabolic rate
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Mantle wedge olivine modifies slab-derived fluids: Implications for fluid transport from slab to arc magma source Geology (IF 5.8) Pub Date : 2023-07-01 Jan C.M. De Hoog, Eleri Clarke, Keiko Hattori
Boron is an effective tracer of fluid processes in subduction zones. High B and δ11B in arc magmas require efficient B transfer from the slab to magma source regions. The Higashi-akaishi metaperidotite body in the Sanbagawa high-pressure belt, Japan, is composed of locally serpentinized mantle wedge peridotites exhumed in a subduction channel. Cores of coarse-grained primary mantle olivine have 1–4
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Do microcontinents nucleate subduction initiation? Geology (IF 5.8) Pub Date : 2023-07-01 Mingshuai Zhu, Zhiyong Yan, Daniel Pastor-Galán, Lin Chen, Laicheng Miao, Fuqin Zhang, Shun Li, Shunhu Yang
Subduction initiation is a pivotal process in plate tectonics. Models of subduction initiation include the collapse of passive margins, oceanic transform faults, inversion of oceanic core complexes, and ridge failure but have ignored the potential effects of continental crust relicts within the oceanic crust. In this paper, we explore the role of microcontinents on subduction initiation through two-dimensional
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ERRATUM: Shallow distributed faulting in the Imperial Valley, California, USA Geology (IF 5.8) Pub Date : 2023-07-01 Valerie J. Sahakian, Boe J. Derosier, Thomas K. Rockwell, Joann M. Stock
ORIGINAL ARTICLE: 2022, v. 50, no. 5, p. 626–630, https://doi.org/10.1130/G49572.1. First published 8 March 2022ERRATUM PUBLICATION: 2023, v. 51, no. 7, p. 704–704, https://doi.org/10.1130/G49572E.1. First published 10 May 2023Figures 3 and 4 were switched in the published paper. Below shows the correct figures and their captions.
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Three-dimensional mineral dendrites reveal a nonclassical crystallization pathway Geology (IF 5.8) Pub Date : 2023-07-01 Zhaoliang Hou, Dawid Woś, Cornelius Tschegg, Anna Rogowitz, A. Hugh N. Rice, Lutz Nasdala, Florian Fusseis, Piotr Szymczak, Bernhard Grasemann
Manganese (Mn) dendrites are a common type of mineral dendrite that typically forms two-dimensional structures on rock surfaces. Three-dimensional (3-D) Mn dendrites in rocks have rarely been reported, and so their growth implications have largely escaped attention. Here, we combined high-resolution X-ray and electron-based data with numerical modeling to give the first detailed description of natural
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Fossil Java Sea corals record Laurentide ice sheet disappearance Geology (IF 5.8) Pub Date : 2023-07-01 Thomas Mann, Tilo Schöne, Paul Kench, Kurt Lambeck, Erica Ashe, Dominik Kneer, Eddie Beetham, Julia Illigner, Alessio Rovere, Muh Aris Marfai, Hildegard Westphal
The Laurentide ice sheet was the largest late Pleistocene ice mass and the largest contributor to Holocene pre-industrial sea-level rise. While glaciological dates suggest final ice sheet melting between 8 and 6 ka, inversion of sea-level data indicates deglaciation at ca. 7 ka. Here, we present new chronostratigraphic constraints on Laurentide ice sheet disappearance based on Holocene relative sea-level
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Collapse of terrestrial ecosystems linked to heavy metal poisoning during the Toarcian oceanic anoxic event Geology (IF 5.8) Pub Date : 2023-07-01 Viktória Baranyi, Xin Jin, Jacopo Dal Corso, Zhiqiang Shi, Stephen E. Grasby, David B. Kemp
The Early Jurassic Toarcian oceanic anoxic event (T-OAE, ca. 183 Ma) was accompanied by a major biotic turnover in the oceans and substantial vegetation change on land. The marine biotic crisis has been attributed to several triggers, e.g., anoxia, warming, ocean acidification, yet the processes underlying the collapse of the terrestrial ecosystem are poorly understood. New high-resolution geochemical
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The source of tungsten-associated magmas in the northern Canadian Cordillera and implications for the basement Geology (IF 5.8) Pub Date : 2023-07-01 Kirsten L. Rasmussen, Hendrik Falck, Vanessa Elongo, Jesse Reimink, Yan Luo, D. Graham Pearson, Luke Ootes, Robert A. Creaser, Pilar Lecumberri-Sanchez
The crustally derived Tungsten Plutonic Suite (TPS) in the northern Canadian Cordillera is responsible for several of the world’s most important tungsten (W) resources, but the actual source rocks to these exceptionally metallogenic magmas have never been identified. Detrital zircon studies have improved our knowledge of exposed supracrustal packages in the region, such that a U-Pb study of inherited
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Breaking plates: Creation of the East Anatolian fault, the Anatolian plate, and a tectonic escape system Geology (IF 5.8) Pub Date : 2023-07-01 Donna L. Whitney, Jonathan R. Delph, Stuart N. Thomson, Susan L. Beck, Gilles Y. Brocard, Michael A. Cosca, Michael H. Darin, Nuretdin Kaymakci, Maud J.M. Meijers, Aral I. Okay, Bora Rojay, Christian Teyssier, Paul J. Umhoefer
Lateral movement of lithospheric fragments along strike-slip faults in response to collision (escape tectonics) has characterized convergent settings since the onset of plate tectonics and is a mechanism for the formation of new plates. The Anatolian plate was created by the sequential connection of strike-slip faults following ≥10 m.y. of distributed deformation that ultimately localized into plate-bounding
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Silica botryoids from chemically oscillating reactions and as Precambrian environmental proxies Geology (IF 5.8) Pub Date : 2023-07-01 Shahab Varkouhi, Dominic Papineau
In this petrographic and geochemical study, we differentiated diverse quartz botryoids, including circular-concentric, twinned, columnar, wavy, and stromatolite-like structures versus synchronous biotic patterns of similar geometry and size dimensions (filamentous traits and stromatolites) in Precambrian cherts of Barberton, South Africa, and Gunflint, Canada. The botryoidal habits explored retained
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Tracing black shales in the source of a porphyry Mo deposit using molybdenum isotopes Geology (IF 5.8) Pub Date : 2023-07-01 Qiqi Xue, Lipeng Zhang, Shuo Chen, Kun Guo, Tao Li, Zhong Han, Weidong Sun
Porphyry Mo deposits are important suppliers of molybdenum for industrial applications, but the origin and source of metals in these deposits remain debated. Here, we present Mo isotope data for Miocene mineralized porphyritic monzogranites (MPMs) and Paleocene barren biotite monzogranites and tuffs (BMTs) from the Bangpu porphyry Mo (Cu) deposit in the Gangdese metallogenic belt. The results show
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Waterfall height sets the mechanism and rate of upstream retreat Geology (IF 5.8) Pub Date : 2023-07-01 T. Inoue, N. Izumi, J.S. Scheingross, Y. Hiramatsu, S. Tanigawa, T. Sumner
Waterfalls are among the fastest-eroding parts of river networks, but predicting natural waterfall retreat rates is difficult due to multiple processes that can drive waterfall erosion. We lack data on how waterfall height influences the mechanism and rate of upstream waterfall retreat. We addressed this knowledge gap with experiments testing the influence of drop height on waterfall retreat. Our experiments
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Molybdenum isotope signature of microbial nitrogen utilization in siboglinid tubeworms Geology (IF 5.8) Pub Date : 2023-07-01 Xudong Wang, Ting Xu, Jörn Peckmann, Germain Bayon, Zice Jia, Shanggui Gong, Jie Li, Erik Cordes, Yanan Sun, Jun Tao, Duofu Chen, Dong Feng
Many chemosynthesis-based communities prospering in deep-sea environments rely on the metabolic activity of sulfide-oxidizing bacteria. This is the case for vestimentiferan siboglinid tubeworms, whose demand for nutrition is satisfied predominantly by their endosymbiotic bacteria harbored in a specialized organ called the trophosome. Such chemosymbiosis leads to a significantly lower nitrogen isotope
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Deep-water circulation in the northeast Atlantic during the mid- and Late Cretaceous Geology (IF 5.8) Pub Date : 2023-06-01 Shan Liu, F. Javier Hernández-Molina, Sara Rodrigues, David Van Rooij
The Cretaceous ocean was significantly different from its modern counterpart due to its ice-free condition. Deep waters were primarily sourced by evaporation at the ocean surface, although their circulation pattern and bottom-current dynamics have been largely unknown. Here we present a study of deeply buried contourite drifts in the southern proto–Bay of Biscay to unravel the circulation pattern of
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Structural control of Cambrian paleotopography and patterns of transgression in western Laurentia Geology (IF 5.8) Pub Date : 2023-06-01 Paul M. Myrow, Michael Hasson, John F. Taylor, Lidya G. Tarhan, Gerardo Ramirez, George Fowlkes, Jitao Chen
The Cambrian transgression across the Great Unconformity produced one of the largest expansions of shallow marine habitats and associated diversification of marine invertebrate faunas in Earth history. However, identification of the underlying controls on the pattern of transgression of Cambrian seas has been hampered by imprecise or inaccurate age assignments for many formations. Recovery of an Ehmaniella