Fault mirrors in the process zone of a seismogenic fault (Karawanks, Eastern Alps)

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985891%3A_____%2F25%3A00636906" target="_blank" >RIV/67985891:_____/25:00636906 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.17738/ajes.2025.0006" target="_blank" >https://doi.org/10.17738/ajes.2025.0006</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.17738/ajes.2025.0006" target="_blank" >10.17738/ajes.2025.0006</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Fault mirrors in the process zone of a seismogenic fault (Karawanks, Eastern Alps)

Popis výsledku v původním jazyce

Square centimetres sized polished fault surfaces are exposed in the vicinity of a seismic fault in the Obir Caves (Northern Karawanks, Carinthia, Austria). Microtectonic studies reveal that contrary to published natural and experimental fault mirrors, these small-scale faults record almost no displacement. Based on our findings, we propose a new process, in which during the passage of seismic waves, small shaking movements along the slip surfaces with hardly any offset caused the development of polished slickensides. The Obir Caves in the Hochobir massif are located just north of the seismogenic ESE striking, dextral Periadriatic Fault System, which forms the boundary between the Eastern and the Southern Alps. The cave was partially formed along the sinistral Obir Fault, close to which a high density of centimetres to decimetres long polished slickensides have been observed. The knife-sharp slip surfaces are associated with millimetre to centimetre thin layers of ultracataclasites, in either hardly deformed or protocataclastic rocks. The highly mature ultracataclasites record angular to rounded clasts, which are truncated along the polished slickensides, but clear kinematic indicators are generally missing. Injection of the ultracataclasites into the protocataclastic host rocks along millimetre-wide apophysis can be locally observed. Some of the older cataclasite generations are overprinted by stylolites and calcite veins suggesting dissolution precipitation processes after cataclastic flow. The only several centimetres-long polished slickensides with varying properties and orientations cannot have accumulated large displacements but the observed microstructures as well as the geological position in an area with several active faults suggest that the investigated fault surfaces in the Obir Caves formed during seismic slip.

Název v anglickém jazyce

Fault mirrors in the process zone of a seismogenic fault (Karawanks, Eastern Alps)

Popis výsledku anglicky

Square centimetres sized polished fault surfaces are exposed in the vicinity of a seismic fault in the Obir Caves (Northern Karawanks, Carinthia, Austria). Microtectonic studies reveal that contrary to published natural and experimental fault mirrors, these small-scale faults record almost no displacement. Based on our findings, we propose a new process, in which during the passage of seismic waves, small shaking movements along the slip surfaces with hardly any offset caused the development of polished slickensides. The Obir Caves in the Hochobir massif are located just north of the seismogenic ESE striking, dextral Periadriatic Fault System, which forms the boundary between the Eastern and the Southern Alps. The cave was partially formed along the sinistral Obir Fault, close to which a high density of centimetres to decimetres long polished slickensides have been observed. The knife-sharp slip surfaces are associated with millimetre to centimetre thin layers of ultracataclasites, in either hardly deformed or protocataclastic rocks. The highly mature ultracataclasites record angular to rounded clasts, which are truncated along the polished slickensides, but clear kinematic indicators are generally missing. Injection of the ultracataclasites into the protocataclastic host rocks along millimetre-wide apophysis can be locally observed. Some of the older cataclasite generations are overprinted by stylolites and calcite veins suggesting dissolution precipitation processes after cataclastic flow. The only several centimetres-long polished slickensides with varying properties and orientations cannot have accumulated large displacements but the observed microstructures as well as the geological position in an area with several active faults suggest that the investigated fault surfaces in the Obir Caves formed during seismic slip.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2025

Kód důvěrnosti údajů

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

Název periodika

Austrian Journal of Earth Sciences

ISSN

2072-7151

e-ISSN

2072-7151

Svazek periodika

118

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

PL - Polská republika

Počet stran výsledku

18

Strana od-do

115-132

Kód UT WoS článku

001512656800001

EID výsledku v databázi Scopus

2-s2.0-105009300607