Results 91 to 100 of about 3,400 (188)

Stardust Mine: A 2024 gabbroic shergottite from Arizona, USA

Meteoritics &Planetary Science, EarlyView.
Abstract This study provides an initial characterization of Stardust Mine, a fresh gabbroic enriched shergottite collected in Arizona, USA, in September 2024 and is the first Martian meteorite to be unequivocably collected on US soil. Analysis was conducted on the type specimen and finds that Stardust Mine is composed of equal proportions of pyroxene ...
Jennifer T. Mitchell, Natasha R. Stephen, Zsuzsanna P. Allerton, Weiming Ding, Xin‐Yuan Zheng   +4 more
wiley   +1 more source

Mineralogy, mineral chemistry, and redox equilibria in ten aggregate particles from asteroid Bennu

Meteoritics &Planetary Science, EarlyView.
Abstract Examination of 10 Bennu aggregate particles has revealed the presence of many phases which taken together can provide constraints on the oxygen fugacity (fO2) of Bennu samples. Phyllosilicates (saponite and serpentine), carbonates, oxides (magnetite, chromite), sulfides (pyrrhotite, pentlandite), phosphate (hydroxyapatite, Na‐Mg‐phosphate ...
K. Righter, J. Gorce, L. Le, K. Thomas‐Keprta, Z.E. Wilbur, L.P. Keller, Z. Gainsforth, T.J. McCoy, T.J. Zega, S.S. Russell, H.C. Connolly Jr., D.S. Lauretta   +11 more
wiley   +1 more source

The Ames impact structure, Oklahoma: New radioisotopic constraints and implications for North American impact chronology

Meteoritics &Planetary Science, EarlyView.
Abstract The Ames impact structure (Oklahoma) is thought to have formed during the Ordovician Meteor Event, based on conodont biostratigraphy of its crater fill. Here, U–Pb zircon dates from its impact‐melt portion, conducted using secondary ion mass spectrometry and laser ablation–inductively coupled plasma–mass spectrometry (n = 37 spots), yield a ...
Elizabeth J. Catlos, Andrew F. Parisi, Michael E. Brookfield, Timmons Erickson, Sean P.S. Gulick, Axel K. Schmitt, Daniel F. Stockli, Daniel P. Miggins, Ben Ruchte, Mark Cloos   +9 more
wiley   +1 more source

Turbulence in Earth’s core generates large topographic torques on the mantle

Communications Earth & Environment
e Seismic and geodynamic studies indicate that the boundary between the Earth’s liquid outer core and solid mantle is not spherical, but is likely characterized by topography in the form of inverted mountains and valleys that have typical amplitudes of ...
Tobias G. Oliver, Eric G. Blackman, John A. Tarduno, Michael A. Calkins   +3 more
doaj   +1 more source

Oxygen isotope variability in the IIIAB iron meteorites and their relationship to main group pallasites

Meteoritics &Planetary Science, EarlyView.
Abstract The light element distribution in planetary cores and the processes driving core evolution in rocky planets are poorly understood. Magmatic iron meteorites are samples from the cores of ancient embryonic planetesimals and therefore provide a window into the processes governing core evolution. We performed high precision oxygen isotope analyses
R. J. Windmill, I. A. Franchi, X. Zhao, R. C. Greenwood, M. Anand   +4 more
wiley   +1 more source

How P‐Wave Scattering Throughout the Entire Mantle Mimics the High‐Frequency Pdiff and Its Coda

Geophysical Research Letters
We document the arrival of seismic energy in the core shadow zone up to large distances beyond 150° more than 100 s prior to the core phases. Numerical simulations of the energy transport in an established heterogeneity model show that scattering ...
Tuo Zhang, Christoph Sens‐Schönfelder, Marcelo Bianchi, Klaus Bataille   +3 more
doaj   +1 more source

Characterization of coesite‐bearing impact melt glass from the Hapcheon crater, Korea: Trimodal phase architecture, shock metamorphism, and implications for 40Ar/39Ar geochronology

Meteoritics &Planetary Science, EarlyView.
Abstract We present the first micrometer‐scale, phase‐resolved compositional characterization of impact melt glass from the Hapcheon crater (~1.4 km apparent diameter), the first confirmed impact structure on the Korean Peninsula, integrating EPMA‐WDS (5 μm spot), confocal Raman spectroscopy (<1 μm spot), XRD, and 40Ar/39Ar step‐heating geochronology ...
Jin‐Young Lee, Jeongmin Kim, Sei‐Sun Hong   +2 more
wiley   +1 more source

Outcrop and subsurface characterisation of a mixed tidal and wave‐influenced coastline (Triassic Red Beds, SE Spain)

Sedimentology, EarlyView.
ABSTRACT Paralic depositional systems are complex and heterogeneous sedimentary environments, presenting challenges for predicting reservoir architecture and connectivity. Their stratigraphic and facies variability arises from the dynamic interplay between fluvial, tidal and wave processes, and their sensitivity to sea‐level fluctuations, sediment ...
Luis Miguel Yeste, Marc Gil‐Ortiz, Neil David McDougall, Patricia Cabello, César Viseras   +4 more
wiley   +1 more source

Tomographic consistency in imaging lower-mantle plumes and their link to European Cenozoic Rift Volcanism

Earth and Planetary Physics
A wide northeast-trending belt of intraplate alkaline volcanism, exhibiting similar geochemical characteristics, stretches from the Eastern Atlantic Ocean to the Cenozoic rift system in Europe.
Chiara Civiero, Angelo De Min
doaj   +1 more source

Transboundary Spanning in Social Movements: Organizational Structure and Antiracism in the US Extinction Rebellion Movement

Sociological Forum, EarlyView.
ABSTRACT This paper introduces transboundary spanning as a novel concept for social movement analysis. Using Extinction Rebellion (XR) in the United States as a case study, we examine the relational dynamics of social movement boundary spanning: processes wherein actors and organizations engage across symbolic boundaries.
Tobias Müller, Peter Gardner
wiley   +1 more source