Abstract
Optical anisotropy appears from low volatile bituminous to anthracite coal ranks. We conducted heating experiments to understand factors which might be controlling the anisotropy under various load pressures. Results of the experiments were applied to vitrinites separated from Miocene mudstones of the Bessho and Aoki Formations, northern Fossa Magna region, central Japan to understand the burial depth. These mudstones are known to have been affected by hydrothermal alteration during the Pliocene. Estimated burial depths of the formations obtained from the experimental anisotropy data are consistent with the stratigraphcal information of this district. Thus, optical anisotropy of vitrinite is a possible parameter for basin analysis in geology.
