Recent geodynamics, active faults and earthquake focal mechanisms of the zone of pseudosubduction interaction between the Northern and Southern Caucasus microplates in the southern slope of the Greater Caucasus (Azerbaijan)

Our study was focused on the active tectonics of the southern slope of the Greater Caucasus within Azerbaijan. The study area is the zone of under-thrusting (pseudosubduction) interaction between Southern and Northern Caucasus continental microplates, which caused the tectonic stratification of the...

Full description

Bibliographic Details
Main Authors: T. N. Kangarli, F. A. Kadirov, G. J. Yetirmishli, F. A. Aliyev, S. E. Kazimova, А. M. Aliyev, R. T. Safarov, U. G. Vahabov
Format: Article
Language:English
Published: Russian Academy of Sciences, Siberian Branch, Institute of the Earth's crust 2018-12-01
Series:Геодинамика и тектонофизика
Subjects:
Online Access:https://www.gt-crust.ru/jour/article/view/668
_version_ 1797855738359447552
author T. N. Kangarli
F. A. Kadirov
G. J. Yetirmishli
F. A. Aliyev
S. E. Kazimova
А. M. Aliyev
R. T. Safarov
U. G. Vahabov
author_facet T. N. Kangarli
F. A. Kadirov
G. J. Yetirmishli
F. A. Aliyev
S. E. Kazimova
А. M. Aliyev
R. T. Safarov
U. G. Vahabov
author_sort T. N. Kangarli
collection DOAJ
description Our study was focused on the active tectonics of the southern slope of the Greater Caucasus within Azerbaijan. The study area is the zone of under-thrusting (pseudosubduction) interaction between Southern and Northern Caucasus continental microplates, which caused the tectonic stratification of the Alpine formations into various allochthonous and parauthochthonous thrust slices of southern vergency between the Middle Bajocian and Quaternary periods. These slices are grouped into the nappe complexes that form the modern structure of the trough in the study area. The large linearly stretched tectonic units (megazones) correspond to the axis of the Alpine marginal sea basin, the consolidated crust of which is subjected to destruction and thinning. The trough’s Alpine cover was compressed in the underthrust zone and pushed southwards. As a result, an accretionary prism formed allochthonously overlapping the northern side of the Southern Caucasus microplate by the system of gently dipping overthrusts. During the continental stage of Alpine tectogenesis (starting from the end of Miocene), intensive lateral compression process was caused by intrusion of the frontal wedge of the Arabian indenter into the buffer structures of the southern frame of Eurasia. This is evidenced by the GPS monitoring data on modern geodynamic activity, which demonstrates the Southern Caucasus block’s intensive (up to 29 mm/year) intrusion in the northern rhumbs as compared to the relative stability of the Northern Caucasus microplate (0–6 mm/year). This, in turn, is a reflection of the ongoing pseudosubduction regime (continental subduction or S-subduction) at the band of collision junction of these microplates. It is suggested that this process caused historically observed seismic activity in the study area, wherein the earthquakes occurred mainly in the southern slope’s accretionary prism area and the adjacent strip of the Southern Caucasus microplate. In this article, we analyze and correlate the whole range of seismic events that occurred in the study area until 2017 and the focal mechanisms of the recently recorded earthquakes (2012–2016). It is established that earthquake foci are confined either to the intersection nodes of variously trending ruptures with the faults of different directions or to the planes of deep tectonic ruptures and lateral displacements along the unstable contacts between the material complexes with different competence. The focal mechanisms of seismic events reveal various, mostly near-vertical, planes of normal and strike-slip faults. However, the earthquake foci are generally confined to the intersection nodes between the Caucasus and anti-Caucasus-striking rupture dislocations. The results of our studies are interesting in terms of their real-time application for drawing a regional summary of causes for both geodynamic and seismic activity of the Greater Caucasus system and the adjacent areas of Alpine-Himalayan fold belt.
first_indexed 2024-04-09T20:28:23Z
format Article
id doaj.art-0f93536d52a343f6b60a4e90a3997406
institution Directory Open Access Journal
issn 2078-502X
language English
last_indexed 2024-04-09T20:28:23Z
publishDate 2018-12-01
publisher Russian Academy of Sciences, Siberian Branch, Institute of the Earth's crust
record_format Article
series Геодинамика и тектонофизика
spelling doaj.art-0f93536d52a343f6b60a4e90a39974062023-03-30T20:08:03ZengRussian Academy of Sciences, Siberian Branch, Institute of the Earth's crustГеодинамика и тектонофизика2078-502X2018-12-01941099112610.5800/GT-2018-9-4-0385383Recent geodynamics, active faults and earthquake focal mechanisms of the zone of pseudosubduction interaction between the Northern and Southern Caucasus microplates in the southern slope of the Greater Caucasus (Azerbaijan)T. N. Kangarli0F. A. Kadirov1G. J. Yetirmishli2F. A. Aliyev3S. E. Kazimova4А. M. Aliyev5R. T. Safarov6U. G. Vahabov7Institute of Geology and Geophysics of the Azerbaijan National Academy of SciencesInstitute of Geology and Geophysics of the Azerbaijan National Academy of SciencesRepublican Seismic Survey Center of the Azerbaijan National Academy of SciencesInstitute of Geology and Geophysics of the Azerbaijan National Academy of SciencesRepublican Seismic Survey Center of the Azerbaijan National Academy of SciencesCenter of the Geo-Ecological Monitoring of National Geological Survey under the Ministry of Ecology and Natural ResourcesInstitute of Geology and Geophysics of the Azerbaijan National Academy of SciencesInstitute of Geology and Geophysics of the Azerbaijan National Academy of SciencesOur study was focused on the active tectonics of the southern slope of the Greater Caucasus within Azerbaijan. The study area is the zone of under-thrusting (pseudosubduction) interaction between Southern and Northern Caucasus continental microplates, which caused the tectonic stratification of the Alpine formations into various allochthonous and parauthochthonous thrust slices of southern vergency between the Middle Bajocian and Quaternary periods. These slices are grouped into the nappe complexes that form the modern structure of the trough in the study area. The large linearly stretched tectonic units (megazones) correspond to the axis of the Alpine marginal sea basin, the consolidated crust of which is subjected to destruction and thinning. The trough’s Alpine cover was compressed in the underthrust zone and pushed southwards. As a result, an accretionary prism formed allochthonously overlapping the northern side of the Southern Caucasus microplate by the system of gently dipping overthrusts. During the continental stage of Alpine tectogenesis (starting from the end of Miocene), intensive lateral compression process was caused by intrusion of the frontal wedge of the Arabian indenter into the buffer structures of the southern frame of Eurasia. This is evidenced by the GPS monitoring data on modern geodynamic activity, which demonstrates the Southern Caucasus block’s intensive (up to 29 mm/year) intrusion in the northern rhumbs as compared to the relative stability of the Northern Caucasus microplate (0–6 mm/year). This, in turn, is a reflection of the ongoing pseudosubduction regime (continental subduction or S-subduction) at the band of collision junction of these microplates. It is suggested that this process caused historically observed seismic activity in the study area, wherein the earthquakes occurred mainly in the southern slope’s accretionary prism area and the adjacent strip of the Southern Caucasus microplate. In this article, we analyze and correlate the whole range of seismic events that occurred in the study area until 2017 and the focal mechanisms of the recently recorded earthquakes (2012–2016). It is established that earthquake foci are confined either to the intersection nodes of variously trending ruptures with the faults of different directions or to the planes of deep tectonic ruptures and lateral displacements along the unstable contacts between the material complexes with different competence. The focal mechanisms of seismic events reveal various, mostly near-vertical, planes of normal and strike-slip faults. However, the earthquake foci are generally confined to the intersection nodes between the Caucasus and anti-Caucasus-striking rupture dislocations. The results of our studies are interesting in terms of their real-time application for drawing a regional summary of causes for both geodynamic and seismic activity of the Greater Caucasus system and the adjacent areas of Alpine-Himalayan fold belt.https://www.gt-crust.ru/jour/article/view/668earthquakeseismotectonic zonefocal mechanismgeodynamicsaccretionnappe complex
spellingShingle T. N. Kangarli
F. A. Kadirov
G. J. Yetirmishli
F. A. Aliyev
S. E. Kazimova
А. M. Aliyev
R. T. Safarov
U. G. Vahabov
Recent geodynamics, active faults and earthquake focal mechanisms of the zone of pseudosubduction interaction between the Northern and Southern Caucasus microplates in the southern slope of the Greater Caucasus (Azerbaijan)
Геодинамика и тектонофизика
earthquake
seismotectonic zone
focal mechanism
geodynamics
accretion
nappe complex
title Recent geodynamics, active faults and earthquake focal mechanisms of the zone of pseudosubduction interaction between the Northern and Southern Caucasus microplates in the southern slope of the Greater Caucasus (Azerbaijan)
title_full Recent geodynamics, active faults and earthquake focal mechanisms of the zone of pseudosubduction interaction between the Northern and Southern Caucasus microplates in the southern slope of the Greater Caucasus (Azerbaijan)
title_fullStr Recent geodynamics, active faults and earthquake focal mechanisms of the zone of pseudosubduction interaction between the Northern and Southern Caucasus microplates in the southern slope of the Greater Caucasus (Azerbaijan)
title_full_unstemmed Recent geodynamics, active faults and earthquake focal mechanisms of the zone of pseudosubduction interaction between the Northern and Southern Caucasus microplates in the southern slope of the Greater Caucasus (Azerbaijan)
title_short Recent geodynamics, active faults and earthquake focal mechanisms of the zone of pseudosubduction interaction between the Northern and Southern Caucasus microplates in the southern slope of the Greater Caucasus (Azerbaijan)
title_sort recent geodynamics active faults and earthquake focal mechanisms of the zone of pseudosubduction interaction between the northern and southern caucasus microplates in the southern slope of the greater caucasus azerbaijan
topic earthquake
seismotectonic zone
focal mechanism
geodynamics
accretion
nappe complex
url https://www.gt-crust.ru/jour/article/view/668
work_keys_str_mv AT tnkangarli recentgeodynamicsactivefaultsandearthquakefocalmechanismsofthezoneofpseudosubductioninteractionbetweenthenorthernandsoutherncaucasusmicroplatesinthesouthernslopeofthegreatercaucasusazerbaijan
AT fakadirov recentgeodynamicsactivefaultsandearthquakefocalmechanismsofthezoneofpseudosubductioninteractionbetweenthenorthernandsoutherncaucasusmicroplatesinthesouthernslopeofthegreatercaucasusazerbaijan
AT gjyetirmishli recentgeodynamicsactivefaultsandearthquakefocalmechanismsofthezoneofpseudosubductioninteractionbetweenthenorthernandsoutherncaucasusmicroplatesinthesouthernslopeofthegreatercaucasusazerbaijan
AT faaliyev recentgeodynamicsactivefaultsandearthquakefocalmechanismsofthezoneofpseudosubductioninteractionbetweenthenorthernandsoutherncaucasusmicroplatesinthesouthernslopeofthegreatercaucasusazerbaijan
AT sekazimova recentgeodynamicsactivefaultsandearthquakefocalmechanismsofthezoneofpseudosubductioninteractionbetweenthenorthernandsoutherncaucasusmicroplatesinthesouthernslopeofthegreatercaucasusazerbaijan
AT amaliyev recentgeodynamicsactivefaultsandearthquakefocalmechanismsofthezoneofpseudosubductioninteractionbetweenthenorthernandsoutherncaucasusmicroplatesinthesouthernslopeofthegreatercaucasusazerbaijan
AT rtsafarov recentgeodynamicsactivefaultsandearthquakefocalmechanismsofthezoneofpseudosubductioninteractionbetweenthenorthernandsoutherncaucasusmicroplatesinthesouthernslopeofthegreatercaucasusazerbaijan
AT ugvahabov recentgeodynamicsactivefaultsandearthquakefocalmechanismsofthezoneofpseudosubductioninteractionbetweenthenorthernandsoutherncaucasusmicroplatesinthesouthernslopeofthegreatercaucasusazerbaijan