On the Stability of the Lithospheric Geoelectrical Structure Resolution in Tarim – Tien Shan Junction Zone: Application of Various Approaches to the Magnetotelluric Data Inversion

For several decades, the intracontinental Tien Shan orogeny has served as a testing polygon for the study of modern geodynamic and seismic processes, carried out by Russian and foreign scientists at the Research Station RAS (Bishkek). The investigations have big practical significance for developing seismic hazzard zoning strategies. Magnetotelluric sounding, providing unique information on the lithosphere structures and rheology, plays an important role in the complex of applied geological and geophysical methods. The article describes the experience of studying the deep geoelectric structure of one of the most seismically active regions of the Tien Shan, the junction zone of the orogen and the Tarim plate. This experience was obtained during the interpretation of materials from the regional profile of MT soundings that cross this zone. Comparing the results of applying three different approaches to the inversion of magnetotelluric data, which differ not only in software implementations and algorithmic foundations, but also in model dimension, allows us to assess the reliability of the allocation and revealed properties of the main structural elements in the deep conductivity section, which help to clarify the seismotectonic pattern of the studied crustal zone. The objectives of the article also included support for new SinoProbe MT experiments.