Article
Geochemistry & Geophysics
Claudio Faccenna, Thorsten W. Becker, Adam F. Holt, Jean Pierre Brun
Summary: This study explores the mechanisms behind orogeny, distinguishing between upper mantle subduction and whole mantle convection cells, with the latter causing extreme crustal thickening. Research suggests that slab penetration into the lower mantle may trigger whole mantle convection cells, supported by geological evidence.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Daniel Pastor-Galan
Summary: The supercontinent cycle explains the formation and disintegration of landmasses into supercontinents in a quasi-periodic manner. These supercontinents are rigid superplates that control many long-term variations on Earth. However, the existence of the last supercontinent, Pangea, is inconsistent with certain observations, leading to the proposal of a new tectonic reconstruction model to reconcile these inconsistencies.
EARTH-SCIENCE REVIEWS
(2022)
Article
Geochemistry & Geophysics
Alexander Young, Nicolas Flament, Simon E. Williams, Andrew Merdith, Xianzhi Cao, R. Dietmar Muller
Summary: The sedimentary rock record suggests that global sea levels have changed by hundreds of meters throughout Phanerozoic times. This study develops a new framework to model sea level change, combining plate tectonic reconstructions and time-dependent models of past mantle flow. The results show the contributions of different solid Earth mechanisms to sea level change and are consistent with existing constraints and reconstructions.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Multidisciplinary Sciences
Shiyan Zhang, Yongyun Hu, Jun Yang, Xiang Li, Wanying Kang, Jian Zhang, Yonggang Liu, Ji Nie
Summary: The Hadley circulation during the Pangea era is weaker and wider than the present, and this weakening and widening is attributed to increased tropical and subtropical static stability. The poleward shifts of the winter cell's ascending branches are associated with the geographic configuration of the supercontinent Pangea.
Article
Geosciences, Multidisciplinary
A. M. Hinchey, I Knight, H. A. Sandeman, J. G. Hinchey
Summary: During the Carboniferous, the reactivation of strike-slip faults and shear zones controlled the evolution of the northern Appalachian Orogen and the development of transtensional sedimentary basins, such as the Deer Lake Basin in western Newfoundland. The geochemical characteristics of basalt rocks and volcaniclastic deposits in the Deer Lake Basin provide insights into the intra-orogenic basin setting and the influence of faulting on asthenosphere upwelling.
Article
Geochemistry & Geophysics
G. Choblet, F. Deschamps, H. Amit, M. Lasbleis
Summary: The heat flux pattern at Earth's core-mantle boundary has a significant impact on core dynamics, but the traditional linear approximation method has biases. We analyze the influence of thermochemical mantle on seismic velocities and derive a formalism to infer the CMB heat flux from seismic shear velocity anomalies. Applying this formalism provides better fits than the commonly used linear fits.
PHYSICS OF THE EARTH AND PLANETARY INTERIORS
(2023)
Article
Geochemistry & Geophysics
Zhiyu Yi, Yushu Liu, Joseph G. Meert, Tianyue Wang, Baochun Huang
Summary: Paleomagnetic and geochronological data from late Triassic dykes and sills in North China suggest that the East Asian blocks were further north and merged with Pangea earlier than previously thought. This updated reconstruction of Pangea's paleogeography is compatible with a zonal climate model, eliminating the need for the Pangean mega-monsoon hypothesis.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Physics, Fluids & Plasmas
Manojit Ghosh, Ankan Banerjee, Pinaki Pal
Summary: In this study, we report the occurrence of flow reversals induced by the attractor-merging crisis in Rayleigh-Benard convection of electrically conducting low-Prandtl-number fluids in the presence of a uniform external horizontal magnetic field. The collision of two coexisting chaotic attractors with an unstable fixed point in the higher-dimensional phase space leads to a single merged chaotic attractor. The effect of the strength of the magnetic field on the flow reversal phenomena is also explored in detail.
Article
Mathematics
Syarif Syahrul Syazwan Muzhaimey, Nik Nazri Nik Ghazali, Mohd Zamri Zainon, Irfan Anjum Badruddin, Mohamed Hussien, Sarfaraz Kamangar, N. Ameer Ahammad
Summary: This study focuses on improving the thermal performance of microchannel heat sink (MCHS) using the passive reentrant cavity approach. Numerical simulations were conducted on a single-channel model of MCHS to examine the effects of geometrical parameters on pressure drops and heat transfer under steady-state conditions. The results show that the conical-shaped microchannel heat sink significantly enhances convection heat transfer with minimal pressure loss.
Review
Geosciences, Multidisciplinary
M. P. Manu Prasanth, J. Gregory Shellnutt, Tung-Yi Lee
Summary: This study addresses the thermal regimes of large igneous provinces (LIPs) in order to evaluate the main mechanisms of supercontinent breakup. It presents the primary magma solutions and mantle potential temperatures (T-P) of LIPs associated with Pangea and its breakup. The LIPs are divided into Pangean and post-Pangean categories based on the stages of Pangea's amalgamation, rifting, and dispersal. The thermal regimes of the Pangean LIPs are consistent with a mantle plume origin, while the post-Pangean LIPs exhibit more complex thermal relations. The study suggests that mantle plumes act as the source of magma composition and thermal energy, but lithospheric processes control the primary driving mechanism of supercontinent rifting.
EARTH-SCIENCE REVIEWS
(2022)
Article
Geochemistry & Geophysics
William D. Frazer, Jun Korenaga
Summary: Deep mantle plumes imaged by seismic tomography are larger than predicted, suggesting a need for reevaluation of viscosity and origin assumptions. The ponding plume model provides an alternative explanation for thick plumes and buoyancy flux estimates from surface topography.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geosciences, Multidisciplinary
T. Alberti, F. Florindo, P. De Michelis, G. Consolini
Summary: This study uses the theory of tipping points to detect and characterize geomagnetic reversals that occurred 25-36 million years ago. By conducting a high-resolution magnetostratigraphic study, the researchers identify a critical threshold below which a polarity reversal starts. They also build a simple stochastic model to describe the main features of polarity reversals. This novel approach could be helpful in developing a new framework for paleomagnetic studies.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Review
Environmental Sciences
Ross N. Mitchell, Nan Zhang, Johanna Salminen, Yebo Liu, Christopher J. Spencer, Bernhard Steinberger, J. Brendan Murphy, Zheng-Xiang Li
Summary: Over the past 2 billion years, three major supercontinents have been identified, representing self-organization in plate tectonics. Research indicates that the supercontinent cycle is intimately related to whole-mantle convection, serving as both an effect and a cause of mantle convection. Future studies will focus on which oceans close to create a supercontinent and how these predictions are linked to mantle convection.
NATURE REVIEWS EARTH & ENVIRONMENT
(2021)
Article
Astronomy & Astrophysics
T. Rees-Crockford, C. J. Nelson, M. Mathioudakis
Summary: Solar active regions (ARs) are important for driving geoeffective eruptions, but predicting their occurrence on the solar disk remains challenging. This study aims to determine the earliest time at which preemergence signatures, such as the horizontal divergent flow (HDF), can be confidently detected using data from the Solar Dynamics Observatory's Helioseismic and Magnetic Imager. The results show that 37.5% of ARs display an HDF, with an average lead time of 58 minutes between the HDF and flux emergence. A new potential signature of flux emergence is also identified, with lead times of 60-156 minutes. Combining Doppler and magnetic field data may be crucial for reliable indicators of continued flux emergence.
ASTROPHYSICAL JOURNAL
(2022)
Article
Geosciences, Multidisciplinary
Dawen Zhang, Maodu Yan, Chunhui Song, Weilin Zhang, Xiaomin Fang, Bingshuai Li
Summary: This study conducted a magnetostratigraphic study on two sections in Laos and discovered frequent occurrences of polarity reversals within the CNS period, providing a new understanding of the Earth's geodynamic behavior during that time.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Nan Zhang, Nick Dygert, Yan Liang, E. M. Parmentier
GEOPHYSICAL RESEARCH LETTERS
(2017)
Article
Geochemistry & Geophysics
Nan Zhang, Zheng-Xiang Li
Article
Geosciences, Multidisciplinary
Nan Zhang, Zhuo Dang, Chuan Huang, Zheng-Xiang Li
GEOSCIENCE FRONTIERS
(2018)
Article
Geochemistry & Geophysics
Rebecca M. Flowers, Alexis K. Ault, Shari A. Kelley, Nan Zhang, Shijie Zhong
EARTH AND PLANETARY SCIENCE LETTERS
(2012)
Article
Geochemistry & Geophysics
Nan Zhang, Shijie Zhong, Rebecca M. Flowers
EARTH AND PLANETARY SCIENCE LETTERS
(2012)
Article
Geosciences, Multidisciplinary
Nan Zhang, E. M. Parmentier, Yan Liang
GEOPHYSICAL RESEARCH LETTERS
(2013)
Article
Geosciences, Multidisciplinary
Nan Zhang, Shijie Zhong, Allen K. McNamara
Article
Geochemistry & Geophysics
Nan Zhang, Shijie Zhong, Wei Leng, Zheng -Xiang Li
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2010)
Article
Geochemistry & Geophysics
Nan Zhang, E. M. Parmentier, Yan Liang
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2013)
Article
Geochemistry & Geophysics
Shijie Zhong, Nan Zhang, Zheng-Xiang Li, James H. Roberts
EARTH AND PLANETARY SCIENCE LETTERS
(2007)
Article
Geochemistry & Geophysics
Nan Zhang, Russell N. Pysklywec
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2006)
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)