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Original Article |
1 1Department of Earth and Planetary Sciences, Graduate School of Science, Hokkaido University, N10 W4, Kita-ku, Sapporo 060-0810, Japan (e-mail: rtaka@nature.sci.hokudai.ac.jp)
2 2Fukui Prefectural Dinosaur Museum, Terao, Muroko, Katsuyama, Fukui 911-8601, Japan
3 3Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
Carbonate platforms consisting of hermatypic coral, rudists and larger foraminifers formed along the margin of the NE Japanese islands during the mid-Late Aptian. The geographical northern limit of the carbonate platforms extended to c. 36°N at that time, which is the highest latitude for coral and/or rudist formation in the North Pacific region. This geographical extension of the carbonate platform in the NW Pacific indicates extreme climatic warmth in the mid-latitudes and strong poleward heat transport systems. Contemporaneous warming has been detected in European and Australian regions, as represented by the migration of Tethyan fauna toward the boreal realm and the positive excursion of 
13C and negative excursion of 18O in deep-sea carbonates. Our new constraint on the northern limit of ‘reef’ growth reinforces the view that an interval of greenhouse-like warmth punctuated the Late Aptian climate.
