No abstract

A systematic study towards understanding the correlation between polarization direction of crustal anisotropy with seismogenic stress field at different locations of the Shillong-Mikir Plateau and its vicinity in North East India is attempted. We used data from a 17-station broadband seismic network. In our earlier work , crustal anisotropic parameters were determined using ANISOMAT þ for the 17 seismic stations. In this study, we have estimated stress field around the stations using focal mechanism solutions (FMS). Some 215 FMS are obtained by waveform inversion. These solutions are used for stress tensor inversion to estimate stress field around each location. It is observed that polarization direction of crustal anisotropy is consistent with that of the maximum horizontal stress ( Ơmax ) as well as the minimum horizontal stress ( Ơ min ). In addition to this, two orthogonal fast polarizations in some locations are also noted. The bivariate nature of correlations helps us to understand that the major mechanisms of seismic crustal anisotropy are not only due to the regional stress, but active faults and other geological conditions play a significant role in contemporary orientation of seismic crustal anisotropy and seismogenic stress field.

The second International Virtual Workshop on Global Seismology and Tectonics (IVWGST, 2021) was hosted online from 20 to 30 September 2021 by the Geoscience and Technology Division, GSTD, of the Council of Scientific and Industrial Research-North East Institute of Science and Technology (CSIR-NEIST) in Jorhat, India. The main goal of IVWGST (2021) akin to the previous edition was to encourage the participating students who were distressed by the unusual circumstances created by the COVID-19 pandemic to continue engagement in seismology and tectonics via remote access to high-quality lectures and interaction with the international community of seismologists. The lectures presented through Microsoft Teams were delivered by 21 speakers from a variety of geoscience organizations in 10 countries and were attended by over 1750 people from 42 different countries, the majority of whom were students. This article presents a summary of a virtual scientific workshop hosted in the midst of a pandemic, reflections on the experiences gained from it, and exploration of possible improvements for conducting online scientific meetings. We hope this summary of our experience will contribute to larger global impact through including a broader international audience and making such events more diverse, equitable, and inclusive.