Meteorite impact picture of the week

In the future we will present interesting pictures – megascopic to microscopic – from the world of our impact research in roughly weekly intervals. A small accompanying text explains the presentation and, where appropriate, links to further pages are given. New image (12.5. 2019):

Trigonal and cubic Fe2Si polymorphs (hapkeite) in the eight kilograms find of natural iron silicide – a probably new class of meteorites

Excavated from the Chiemgau impact crater strewn field: 8 kg (eight – no printer’s error) iron silicide chunk.
Click presentations from the 50th Lunar & Planetary Science Conference (LPSC):
ABSTRACT    POSTER

 

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Enigmatic Impact Breccias Probably Linked to the Ries Crater (Germany) Impact Event -Alemonites from Bavaria and sunstones from the Czech Republic

Alemonite (DE) and sunstone (CZ) samples from the field 

Shock effects in alemonites and sunstones
Lunar & Planetary Science Conference (LPSC ) 2019 : Click Abstract and Poster!
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Impact spallation – completely underestimated by impact researchers.

shock spallation experiment microscopic megascopic Spanish impact structures

Left, from the top down: Shock spallation experiment producing typical open tensile fractures. – Spallation fractures in shocked quartzite cobble, Azuara/Rubielos de la Cérida impact event (Spain). Microscopic shock spallation in sandstone quartz grains, Rubielos de la Cérida impact basin. – To the right: Local megascopic impact spallation in well-bedded Jurassic limestones; Azuara (Spain) impact structure northern rim region south of Fuendetodos. Link to a full article on impact spallation.

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Rock fluidization, Azuara Impact Structure (Spain)

impact rock fluidization in competent limestone Azuara impact Spain

Rock fluidization in strongly competent limestones/dolostones (Muschelkalk Fm.); Monforte de Moyuela, Azuara impact structure, Spain. See article Rock fluidization during peak-ring formation of large impact structures by U. Riller et al. Also focus on Acoustic fluidization (H.J. Melosh). Enlarged image.

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shock metamorphism in calcite planar features microtwins
shock PDFs in calcite Rubielos de la Cérida Spain

Shock effect in calcite. Multiple sets of closely spaced planar features (micro twins). The width of the twins is of the order of only one micrometer. Thin section micrograph, crossed polarizers. From a polymictic breccia, rim region of the Rubielos de la Cérida impact basin crater chain. (7.9. 2019). Enlarge image!