New article – (and LPSC 2022 contributions)

The Steinheim Basin, the Ries crater “double disaster” and the mistaken Steinheim crater diameter

by Kord Ernstson¹ & Ferran Claudin² (Febr. 2021)

Abstract. – The article, which we comment here, interprets sedimentological findings (seismite horizons) at a distance of 80 – 180 km from the two impact structures, the Ries crater and the Steinheim basin, to the effect that, contrary to the impacts at a distance of only 40 km from each other, which have always been assumed to be synchronous, the Steinheim basin is supposed to be several 10 000 years younger than the Ries impact. This is against all probability, but because of the purely statistical impact events, it cannot be completely ruled out. This article therefore does not criticize the statement itself, but refers to equally probable alternatives that have not been considered, as well as to a lack of literature citations. The article loses its fundamental significance to the point of the simple alternative: it may be, but it also may not be, a finding without recognizable importance. A major point of criticism of the article is the common practice in the impact literature of suppressing the diameter of the Steinheim impact structure, which at around 7-8 km is actually twice as large, as it was proven almost 40 years ago by detailed morphological analyses and gravimetric measurements and published in a renowned journal. Since the size of the Steinheim Basin is included in the estimates for the formation of the seismites, it must be stated that the authors started from partly false premises. Here, the findings on the much larger Steinheim impact structure, which cannot be explained away, are presented again, combined with the wish to deal with scientific findings more honestly.

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1 University of Würzburg, 97074 Würzburg (Germany); kernstson@ernstson.de; 2 Associate Geological Museum Barcelona (Spain); fclaudin@xtec.cat

A PDF of the complete article may be downloaded here.

Continue reading “The Steinheim Basin, the Ries crater “double disaster” and the mistaken Steinheim crater diameter”

METALLIC ARTIFACT REMNANTS IN A SHOCK-METAMORPHOSED IMPACT BRECCIA: AN EXTENDED VIEW OF THE ARCHEOLOGICAL EXCAVATION AT STÖTTHAM (CHIEMGAU, SE GERMANY)

POSTER LPSC

Poster Meeting Syktyvkar Yushkin Readings 2020

Shocked calcite

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.

Rock fluidization, Azuara Impact Structure (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.

Impact spallation – completely underestimated by impact researchers.

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.

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!

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: 50th Lunar & Planetary Science Conference (LPSC):

ABSTRACT    POSTER

Impact sulfate melt rock from the Rubielos de la Cérida  impact basin (Azuara impact event, Spain) – a rare meteorite impact signature

Strongly shocked quartzite clasts in the low-density, highly porous CaSO4 matrix.

Clast of sulfate melt rock in the Barrachina megabreccia -The sulfate melt rock under the SEM. Note the vesicular texture. – More about Azuara and Rubielos de la Cérida impact melt rocks (carbonate melt, carbonate-phosphate melt, silicate melt, carbonate-psilomelan melt).

Polymictic impact breccia dike sharply cutting through well-bedded Muschelkalk limestone. – Rubielos de la Cérida impact basin (Spain) near Olalla.

Very nice example of the many breccia dikes in the Spanish Azuara impact structure and the Rubielos de la Cérida impact basin (crater chain). – More about impressive breccia dikes (dike breccias) in the Rubielos de la Cérida basin and the Azuara structure.

Impact breccia in lapillistone matrix. – Rubielos de la Cérida impact basin (Spain) near Olalla.

Muschelkalk breccia-within-breccia, lapillistone matrix (accretionary lapilli).