Mitsuo Yoshida

Department of Geology and Mineralogy, Hokkaido University

Sapporo 060, Japan (Present Address: Department of Geology, Trichandra Campus, Tribhuvan University, Kathmandu, Nepa)l

Yaeko Igarashi and Kazunori Arita

Department of Geology and Mineralogy, Hokkaido University, Sapporo 060, Japan

Daigoro Hayashi

Department of Marine Sciences, University of the Ryukyus, Okinawa 903-01, Japan

Toran Sharma

Department of Mines and Geology, Kathmandu, Nepal

Thick terrestrial sediments accumulated in the Thak Khola-Mustang graven. These are stratigraphically divided into three units; the Tetang Formation, Thak Khola Formation and fluvio-glacial to glacio-lacustrine deposits. These are subdivided into four magneto-polarity zones; the lowest normal polarity zone (TA-A and TA-C), lower mixed polarity zone (TA-B and TA-D), middle mixed polarity zone (TA-E) and the upper normal polarity zone (TA-F). The upper normal polarity zone is correlated with the Brunhes Normal Epoch. There is a possibility that the middle to lowest magneto-polarity zones may range from Matsuyama Reversed Epoch to Epoch 5.

The paleoclimate during deposition of the Tetang Formation was quite warmer than that of the present time. Furthermore, a dry climate circumstance is dominant in this area.