A. V. Marinin, L. A. Sim, E. A. Manuilova, I. V. Bondar, N. A. Gordeev
{"title":"Neotectonic Stress State of the Chuya–Kurai Depression and Adjacent Structures (Southeastern Altai Mountains)","authors":"A. V. Marinin, L. A. Sim, E. A. Manuilova, I. V. Bondar, N. A. Gordeev","doi":"10.3103/S0747923922080096","DOIUrl":null,"url":null,"abstract":"<p>A set of tectonophysical methods has been applied to reconstruct the neotectonic stresses of the southeastern Altai Mountains within the Chuya–Kurai depression and its framing structures. It is suggested that at the neotectonic stage, the tectonic structures of the Altai Mountains underwent a transformation of geodynamic conditions—a situation of sublatitudinal horizontal compression with predominant reverse-fault and transpressional movements along faults that existed up to the Neogene was replaced by horizontal shear conditions with a NNE and NE subhorizontal compression axis and WNW and NW extension axis. With such a stress field, the dominant NW-trending faults in this territory are mainly characterized by dextral strike-slip displacements, and NE-trending faults, by sinistral. Submeridionally trending faults that formed at the neotectonic stage show clear signs of extensional structures. A feature of the faults of the Chuya–Kurai depression according to these studies is a fairly small number of megafractures (indicators of shear displacements) in shear zones. This indicates dominant reverse-fault and transpressional movements over large disjunctive structures in the region in the Paleozoic and Mesozoic versus neotectonic shear movements. The results of the research are of practical importance in studying the regional seismicity.</p>","PeriodicalId":45174,"journal":{"name":"Seismic Instruments","volume":"58 2","pages":"S345 - S355"},"PeriodicalIF":0.3000,"publicationDate":"2023-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Seismic Instruments","FirstCategoryId":"1085","ListUrlMain":"https://link.springer.com/article/10.3103/S0747923922080096","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"GEOCHEMISTRY & GEOPHYSICS","Score":null,"Total":0}
引用次数: 0
Abstract
A set of tectonophysical methods has been applied to reconstruct the neotectonic stresses of the southeastern Altai Mountains within the Chuya–Kurai depression and its framing structures. It is suggested that at the neotectonic stage, the tectonic structures of the Altai Mountains underwent a transformation of geodynamic conditions—a situation of sublatitudinal horizontal compression with predominant reverse-fault and transpressional movements along faults that existed up to the Neogene was replaced by horizontal shear conditions with a NNE and NE subhorizontal compression axis and WNW and NW extension axis. With such a stress field, the dominant NW-trending faults in this territory are mainly characterized by dextral strike-slip displacements, and NE-trending faults, by sinistral. Submeridionally trending faults that formed at the neotectonic stage show clear signs of extensional structures. A feature of the faults of the Chuya–Kurai depression according to these studies is a fairly small number of megafractures (indicators of shear displacements) in shear zones. This indicates dominant reverse-fault and transpressional movements over large disjunctive structures in the region in the Paleozoic and Mesozoic versus neotectonic shear movements. The results of the research are of practical importance in studying the regional seismicity.
期刊介绍:
Seismic Instruments is a journal devoted to the description of geophysical instruments used in seismic research. In addition to covering the actual instruments for registering seismic waves, substantial room is devoted to solving instrumental-methodological problems of geophysical monitoring, applying various methods that are used to search for earthquake precursors, to studying earthquake nucleation processes and to monitoring natural and technogenous processes. The description of the construction, working elements, and technical characteristics of the instruments, as well as some results of implementation of the instruments and interpretation of the results are given. Attention is paid to seismic monitoring data and earthquake catalog quality Analysis.