TY - JOUR

T1 - Tectonic Evolution of the Tuvinian Trough (Northern Part of Central Asian Orogenic Belt): Synthesis of Geological Data and Results of Feldspar Ar‒Ar Dating

AU - Vetrov, E. V.

AU - Vetrova, N. I.

AU - Biryukova, T. A.

AU - Agatova, A. R.

AU - Gavryushkina, O. A.

AU - Bulgakova, D. D.

N1 - The study was supported by the Russian Science Foundation, grant no. 22-77-10 069.

PY - 2024/8

Y1 - 2024/8

N2 - Abstract: The Tuvinian rift trough, located in the northern part of the Central Asian orogenic belt (CAOB), arose in the Early Devonian on Late Proterozoic (?)‒Early Paleozoic terranes as a result of Altai–Sayan mantle plume activity. The sedimentary record from the Middle Paleozoic to the Middle Mesozoic, preserved in the Tuvinian trough, and the Middle Paleozoic igneous complexes confined to the trough structures, reflect the evolutionary stages of Earth’s crust in the Tuva segment necessary for understanding the geological history of the CAOB as a whole. Dating of accessory and rock-forming minerals from igneous rocks using low-temperature geochronology methods yields additional information about postmagmatic processes, making it possible to update the regional tectonic evolution model. In this study, we have reconstructed the stages of tectonic development of the Tuvinian trough in the northern part of the CAOB based on analysis of geological and new Ar‒Ar dating data on feldspars from mafic intrusions. As a result, the chronology of the previously known stages of postmagmatic processes manifested in the Tuvinian trough was refined and new stages identified according to the tectonic evolution of the CAOB. Ar‒Ar dating of feldspars from eight samples yielded four age groups: (i) Late Devonian, (ii) Middle Carboniferous, (iii) Early Permian, and (iv) Early Jurassic. Late Devonian (~377 and 375 Ma) ages record an impulse of mafic magmatism, widely manifested in the northern segments of the CAOB (~380‒365 Ma). Middle Carboniferous (~320 and 319 Ma) dates may reflect closure of the Ob–Zaisan branch of the Paleo-Asian ocean as a result of the Kazakhstan–Siberian collision. Early Permian (~290–279 Ma) ages are consistent with the formation of Late Carboniferous–Early Permian (~305–275 Ma) large igneous provinces in connection with rifting processes in the northern segments of the CAOB. Lastly, a single Early Jurassic (~188 Ma) age marks tectonic reorganization of the CAOB in the Late Triassic‒Early Jurassic in response to (i) closure of the Paleotethys Ocean with subsequent collision of Cimmerian blocks and the southern margin of the Eurasian continent and/or (ii) Mongolian mantle plume activity.

AB - Abstract: The Tuvinian rift trough, located in the northern part of the Central Asian orogenic belt (CAOB), arose in the Early Devonian on Late Proterozoic (?)‒Early Paleozoic terranes as a result of Altai–Sayan mantle plume activity. The sedimentary record from the Middle Paleozoic to the Middle Mesozoic, preserved in the Tuvinian trough, and the Middle Paleozoic igneous complexes confined to the trough structures, reflect the evolutionary stages of Earth’s crust in the Tuva segment necessary for understanding the geological history of the CAOB as a whole. Dating of accessory and rock-forming minerals from igneous rocks using low-temperature geochronology methods yields additional information about postmagmatic processes, making it possible to update the regional tectonic evolution model. In this study, we have reconstructed the stages of tectonic development of the Tuvinian trough in the northern part of the CAOB based on analysis of geological and new Ar‒Ar dating data on feldspars from mafic intrusions. As a result, the chronology of the previously known stages of postmagmatic processes manifested in the Tuvinian trough was refined and new stages identified according to the tectonic evolution of the CAOB. Ar‒Ar dating of feldspars from eight samples yielded four age groups: (i) Late Devonian, (ii) Middle Carboniferous, (iii) Early Permian, and (iv) Early Jurassic. Late Devonian (~377 and 375 Ma) ages record an impulse of mafic magmatism, widely manifested in the northern segments of the CAOB (~380‒365 Ma). Middle Carboniferous (~320 and 319 Ma) dates may reflect closure of the Ob–Zaisan branch of the Paleo-Asian ocean as a result of the Kazakhstan–Siberian collision. Early Permian (~290–279 Ma) ages are consistent with the formation of Late Carboniferous–Early Permian (~305–275 Ma) large igneous provinces in connection with rifting processes in the northern segments of the CAOB. Lastly, a single Early Jurassic (~188 Ma) age marks tectonic reorganization of the CAOB in the Late Triassic‒Early Jurassic in response to (i) closure of the Paleotethys Ocean with subsequent collision of Cimmerian blocks and the southern margin of the Eurasian continent and/or (ii) Mongolian mantle plume activity.

KW - Ar‒Ar dating

KW - Carboniferous

KW - Central Asian orogenic belt

KW - Devonian

KW - Jurassic

KW - Tuvinian trough

KW - mafic intrusions

KW - tectonic stages

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85210091578&origin=inward&txGid=64c36aa857b94caec11f3595795498ec

UR - https://www.mendeley.com/catalogue/d4abc3bf-a416-3fd3-b32e-4a60ddfecc3c/

U2 - 10.1134/S0016852124700328

DO - 10.1134/S0016852124700328

M3 - Article

VL - 58

SP - 449

EP - 464

JO - Geotectonics

JF - Geotectonics

SN - 0016-8521

IS - 4

ER -