抄録
Foraminiferal fossils from the lower Pleistocene around Seikan district were investigated to reconstruct palegeography in this district. Warm water planktonic foraminiferal fossils occurred from two horizons. Planktonic fauna from these horizons were slightly different. Lower horizon was characterized by occurrence of Globorotalia inflata inflata, and upper Globigerinoides ruber. Warm water benthic foraminiferal species such as Hanzawaia nipponica and Paracassidulina sagamiensis, were accompanied with only the upper horizon. This difference may be reflect the character of the warm currents. Early warm current might not be warm enough for G. ruber. These warm currents might flow through the paleo-Tsugaru Strait. Warm water foraminiferal fossils from the lower Pleistocene strata in the Seikan district might be brought by branches of those warm currents.
https://ror.org/02syg0q74 
