Evaluation of Climatic and Tectonic Imprints In Fluvial Successions of An Early Permian Depositional System (Asselian Vrchlabí Formation, Krkonoše Piedmont Basin, Czech Republic)

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F22%3A10455969" target="_blank" >RIV/00216208:11310/22:10455969 - isvavai.cz</a>

Result on the web

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

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.2110/jsr.2020.137" target="_blank" >10.2110/jsr.2020.137</a>

Result language

angličtina

Original language name

Evaluation of Climatic and Tectonic Imprints In Fluvial Successions of An Early Permian Depositional System (Asselian Vrchlabí Formation, Krkonoše Piedmont Basin, Czech Republic)

Original language description

The Krkonoše Piedmont Basin, an early post-Variscan basin (c. 310-280 Ma) located in the NE Bohemian Massif (Czech Republic, central Europe), contains up to 300-m-thick non-marine Lower Permian (Asselian) deposits of the Vrchlabí Formation that crop out in its western part. The Early Permian Krkonoše Piedmont Basin exhibits striking similarities-in terms of tectonostratigraphic evolution, depositional patterns, and volcanism-to other early post-Variscan, near-equatorial intermontane basins. This work focuses on sedimentological analysis of the Vrchlabí Formation using outcrop data, combined with borehole and newly acquired field gamma spectrometry data. The formation consists predominantly of fluvial deposits in the southern part of the basin that pass laterally into deltaic and lacustrine deposits of the Rudnfk Member, located in the central part of the basin. Fluvial deposits are formed by sandstone and conglomeratic bodies, decimeters to several meters thick, interpreted as single-story and multi-story channel fills as well as various macroforms (e.g., bars) deposited by a low-sinuosity fluvial system. Channel fills intercalate with floodplain deposits centimeters to few meters thick. Vertically, the studied fluvial succession is divided into five intervals based on i) variable preservation ratio between channel fill and floodplain deposits and ii) external and internal geometries of sandstone and conglomerate channel bodies. In order to explain the observed vertical changes in fluvial style and to determine the main controlling factors, the interaction of the fluvial system with the contemporaneous lake was investigated by interpreting base-level changes of the fluvial system and their correlation with lake level changes. In the central part of the basin the transition from fluvio-deltaic to lacustrine deposits is represented by alternating beige to gray sandstones centimeters to few meters thick and by dark gray mudstones up to several meters thick that pass northwards into shales. At the outcrop scale, the new sedimentological data in combination with newly acquired gamma-ray logs enabled tracing the lateral extent of individual fluvial bodies. The integration of the new data with older borehole data leads to a substantially better understanding of lateral and vertical relationship between the fluvio-deltaic and the lacustrine facies at the basin scale. Tectonic subsidence played a substantial role during the initial deposition of the Vrchlabí Formation. However, the external geometries, the internal architecture of fluvial channel bodies, and the variable degree of floodplain preservation throughout the entire Vrchlabí Formation cannot be explained by tectonics only, but requires the consideration of climatic controls. The Early Permian fluvial system is interpreted to reflect seasonal discharge variability with dry and wet periods under long-term subhumid climatic conditions that shifted towards more arid conditions during the latest depositional stage of the Vrchlabí Formation.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10505 - Geology

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2022

Confidentiality

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

Name of the periodical

Journal of Sedimentary Research

ISSN

1527-1404

e-ISSN

1938-3681

Volume of the periodical

92

Issue of the periodical within the volume

3

Country of publishing house

US - UNITED STATES

Number of pages

29

Pages from-to

275-303

UT code for WoS article

000787774000004

EID of the result in the Scopus database

2-s2.0-85131098381