Results 101 to 110 of about 3,902 (277)

Determining impact angle from the spatial distribution of shock metamorphism: A case study of the Gosses Bluff (Tnorala) impact structure, Australia

Meteoritics &Planetary Science, EarlyView.
Abstract The majority of planetary impacts occur at oblique angles. Impact structures on Earth are commonly eroded or buried, rendering the identification of the direction and angle of impact—using methods such as asymmetries in ejecta distribution, surface topographic expression, central uplift structure, and geophysical anomalies—challenging. In this
Eloise E. Matthews, Auriol S. P. Rae, Thomas Kenkmann, Nicholas E. Timms, Aaron J. Cavosie, Marian B. Holness   +5 more
wiley   +1 more source

Vertical profiling of shock attenuation at the Rochechouart impact structure, France

Meteoritics &Planetary Science, EarlyView.
Abstract Rochechouart, south‐west France, is a complex impact structure. Here, we present the first report of shock barometry of quartz from what are likely parautochthonous basement units at depth, based on samples from the 2017 C.I.R.I.R drilling campaign. The crystallographic orientations of 725 sets of PDFs in 512 quartz grains in samples from four
P. Struzynska, S. Alwmark, C. Alwmark, M. H. Poelchau, P. Lambert   +4 more
wiley   +1 more source

Static recrystallization of shocked calcite in Ries impact breccias

Meteoritics &Planetary Science, EarlyView.
Abstract Calcite is prone to chemical and microstructural modifications, especially after having been strained at high stresses and strain rates, as during hypervelocity impact events. These modifications include precipitation from pore fluid as well as replacement of strained volumes by recrystallization. In calcite aggregates of a metagranite breccia
Claudia A. Trepmann, Fabian Dellefant, Lina Seybold, Wolfgang W. Schmahl, Elena Sturm, Daniel Weidendorfer, Sandro Jahn, Iuliia V. Sleptsova, Stuart A. Gilder   +8 more
wiley   +1 more source

Publisher Correction: Evaluating machine learning techniques for archaeological lithic sourcing: a case study of flint in Britain [PDF]

, 2021
Tom Elliot, Robert Morse, Duane Smythe, C. Ashley Norris   +3 more
openalex   +1 more source

Confirmation of the impact origin of the Late Ordovician Tvären impact structure (southeast Sweden) and emplacement of impactites in a marine setting

Meteoritics &Planetary Science, EarlyView.
Abstract The Tvären structure in southeastern Sweden has been listed as a confirmed marine‐target impact structure for decades. However, to date, no measurements and/or indexed data of planar deformation features in quartz grains from the structure have been published or any other unequivocal evidence of impact.
Katarzyna J. Gajewska, Sanna Alwmark, Mikael Calner, Sylvain Richoz, Jens Ormö, Erik Sturkell, Carl Alwmark   +6 more
wiley   +1 more source

Polymict melt‐bearing breccia dikes in the Morokweng impact structure formed by slip‐induced mechanical mixing of pseudotachylite and cataclasite along large‐displacement impact faults

Meteoritics &Planetary Science, EarlyView.
Abstract A core drilled through shocked and faulted Archean granitoid gneisses and dolerites in the eroded peak ring of the 70–80 km diameter Morokweng impact structure intersects multiple centimeter‐ to meter‐wide clastic‐matrix breccias containing a polymict clast population of lithic and mineral clasts and altered, millimeter‐ to centimeter ‐size ...
Roger L. Gibson, S'lindile S. Wela, Leonidas C. Vonopartis, Marco A. G. Andreoli   +3 more
wiley   +1 more source

Lithic Technology in Italy. Reflections on the Study of Prehistoric Lithic Industries after 30 Years of "Eric Boëda Method"

IpoTESI di Preistoria, 2018
During last three decades, the technological approach confirmed to be a useful tool to understand stone tools. This approach is mostly based on the well known methodology proposed by the French scholar E. Boëda. Here we propose to reconsider the epistemological value of the Boëda’s technological approach: diachronic and synchronic technical changes ...
Stefano Grimaldi, Fabio Santaniello
openaire   +1 more source

Bio‐mediated cementation of supratidal beach sediments associated with groundwater springs

Sedimentology, EarlyView.
ABSTRACT The formation of beachrock, sensu stricto, via carbonate precipitation in the intertidal zone is widespread throughout the tropics and subtropics. While cementation of supratidal beach sediments has also been noted in several locations, it has received much less attention.
Thomas William Garner, J. Andrew G. Cooper   +1 more
wiley   +1 more source

Response to Comment on ‘Cave Palaeolithic of the Ural Mountains—a review’

Boreas, EarlyView.
Jiri Chlachula
wiley   +1 more source

A review of the supercritical state of eruption‐fed volcanic density currents in subaerial and subaqueous settings

Sedimentology, EarlyView.
ABSTRACT Subaerial Pyroclastic Density Currents (PDCs) and Subaqueous Eruption‐Fed Density Currents (SEFDCs) produced during volcanic eruptions can present major hazards to surrounding communities and ecosystems. The bedforms deposited by these volcanic density currents can provide insights into the nature of transport and depositional processes, which
Shannon E. Frey, Martin Jutzeler, Rebecca J. Carey   +2 more
wiley   +1 more source