Two Holocene impact craters at Emmerting, Germany: deformation, fracturing, and their relationships to the melting and decarbonization

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F25%3A10500462" target="_blank" >RIV/00216208:11310/25:10500462 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=VlkF6-V0-i" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=VlkF6-V0-i</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.23939/jgd2025.01.005" target="_blank" >10.23939/jgd2025.01.005</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Two Holocene impact craters at Emmerting, Germany: deformation, fracturing, and their relationships to the melting and decarbonization

Popis výsledku v původním jazyce

In two craters near Emmerting, three major processes which variably affected the original pebbles are documented in the following order: 1. Deposition of hot material which solidified to glass (usually thin and transparent) or reacted with carbonate to form expanded &quot;pumice&quot; on the surface of pebbles. 2. Ductile deformation of variable intensity (with limited fragile deformation but intense fracturing of mineral grains), using older as well as newly formed discontinuities; in some cases this deformation had to be associated with extreme strain, excluding interpretation of the crater formation by any plausible human activity. The largely ductile character of deformation points to a high temperature, but it was not necessarily accompanied by melting. 3. Solidification of melts generated within pebbles or derived from secondary projectiles. These disequilibrium melts were hot enough to have very low viscosity (in some cases, they may have also been injected by high pressure/strain, or sucked in), which enabled them to fill even thin fractures in individual mineral grains; gas expansion also formed extrusions resembling miniature volcanic features on the surface of some pebbles. In one zircon grain baddeleyite was observed, probably formed by shock metamorphism. However, no additional evidence was found to suggest pressures exceeding the threshold typically required for shock-induced melting (approx. 8 Gpa or more). Nevertheless, the energy transformed during repeated mutual collisions may have heated the interior of pebbles sufficiently. Origin of the depression at Grabenstatt-Kaltenbach is unclear, the disequilibrium melting and decarbonization may also be explained by anthropogenic processes.

Název v anglickém jazyce

Two Holocene impact craters at Emmerting, Germany: deformation, fracturing, and their relationships to the melting and decarbonization

Popis výsledku anglicky

In two craters near Emmerting, three major processes which variably affected the original pebbles are documented in the following order: 1. Deposition of hot material which solidified to glass (usually thin and transparent) or reacted with carbonate to form expanded &quot;pumice&quot; on the surface of pebbles. 2. Ductile deformation of variable intensity (with limited fragile deformation but intense fracturing of mineral grains), using older as well as newly formed discontinuities; in some cases this deformation had to be associated with extreme strain, excluding interpretation of the crater formation by any plausible human activity. The largely ductile character of deformation points to a high temperature, but it was not necessarily accompanied by melting. 3. Solidification of melts generated within pebbles or derived from secondary projectiles. These disequilibrium melts were hot enough to have very low viscosity (in some cases, they may have also been injected by high pressure/strain, or sucked in), which enabled them to fill even thin fractures in individual mineral grains; gas expansion also formed extrusions resembling miniature volcanic features on the surface of some pebbles. In one zircon grain baddeleyite was observed, probably formed by shock metamorphism. However, no additional evidence was found to suggest pressures exceeding the threshold typically required for shock-induced melting (approx. 8 Gpa or more). Nevertheless, the energy transformed during repeated mutual collisions may have heated the interior of pebbles sufficiently. Origin of the depression at Grabenstatt-Kaltenbach is unclear, the disequilibrium melting and decarbonization may also be explained by anthropogenic processes.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

<a href="/cs/project/GA23-06075S" target="_blank" >GA23-06075S: Environmentální změny způsobené extraterestrickými impakty a vulkanismem: Doklady v jezerních sedimentech</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Geodinamìka

ISSN

1992-142X

e-ISSN

2519-2663

Svazek periodika

38

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

UA - Ukrajina

Počet stran výsledku

20

Strana od-do

5-24

Kód UT WoS článku

001534161700001

EID výsledku v databázi Scopus

2-s2.0-105011172585