Chemistry of Tertiary sediments in the surroundings of the Ries impact structure and moldavite formation revisited

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025798%3A_____%2F16%3A00000022" target="_blank" >RIV/00025798:_____/16:00000022 - isvavai.cz</a>

Alternative codes found

RIV/67985831:_____/16:00458591 RIV/61389005:_____/16:00458591 RIV/00216208:11310/16:10328901

Result on the web

<a href="http://www.sciencedirect.com/science/journal/00167037" target="_blank" >http://www.sciencedirect.com/science/journal/00167037</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.gca.2016.01.025" target="_blank" >10.1016/j.gca.2016.01.025</a>

Result language

angličtina

Original language name

Chemistry of Tertiary sediments in the surroundings of the Ries impact structure and moldavite formation revisited

Original language description

Moldavites have been linked with the Ries impact in Germany. They are supposed to be derived mainly from the near-surface sediments of the Upper Freshwater Molasse (OSM) that probably covered the target area before the impact. Comparison of the chemical composition of moldavites with that of inferred source materials requires recalculation of the composition of sediments to their volatile-free residuum. This recalculation reflects almost complete loss of volatiles from the target materials during their transformation to moldavites. Strong depletions of many elements in moldavites relative to the source sediments (e.g., Mo, Cu, Ag, Sb, As, Fe) contrast with enrichments of some elements in moldavites (e.g., Cs, Ba, K, Rb). This can be solved using either involvement of a specific component, or by considering elemental fractionation during tektite formation. The proposed model of moldavite formation combines both approaches and is based on several steps: (i) the parent mixture (dominated by OSM sediments) contained also a minor admixture of organic matter and soils; (ii) the most energetic part of the ejected matter was converted to vapor (plasma) and another part produced melt directly upon decompression; (iii) following further adiabatic decompression, the expanding vapor phase disintegrated the melt into small melt droplets and some elements were partially lost from the melt because of their volatility, or because of the volatility of their compounds, (e.g. carbonyls of Fe and other transition metals); (iv) large positively charged ions (Cs+, Ba2+, K+, Rb+) from the plasma were enriched in late-stage condensation spherules or condensed directly onto negatively charged melt droplets; (v) melt droplets coalesced into larger tektite bodies. Steps (iii) to (v) may have overlapped in time.

Czech name

—

Czech description

—

Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

DD - Geochemistry

OECD FORD branch

—

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

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

Publication year

2016

Confidentiality

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

Name of the periodical

Geochimica et Cosmochimica Acta

ISSN

0016-7037

e-ISSN

—

Volume of the periodical

179

Issue of the periodical within the volume

April

Country of publishing house

GB - UNITED KINGDOM

Number of pages

25

Pages from-to

287-311

UT code for WoS article

000372565800016

EID of the result in the Scopus database

—