TY JOUR TI Complex analysis of the structure of the Lower Jurassic J1-I bed within the Khapchagai megaswell of the Vilyuy syneclise KW cyclites KW facies KW delta KW transgression KW Lower Jurassic deposits KW Kyzyl-Syr formation KW Vilyuy syneclise KW Eastern Siberia JO Vestnik of geosciences AU Deliu, E.A. AU Taskaeva, E.V. PY 2026 IS 0 PB FSBI FIC "Komi Scientific Center of the Ural Branch of the Russian Academy of Sciences"